Flashless intravascular ultrasound technology

Abstract

A system and method for filling and sealing a flashless intravascular ultrasound (IVUS) catheter with an acoustically coupled medium are provided in specific embodiments. The IVUS catheter includes, for example, an acoustically coupled medium inlet filling port, a distal outlet port, a seal, and a plug. The method for filling the IVUS catheter can advantageously reduce or eliminate air bubbles from the acoustically coupled medium surrounding the ultrasound imaging core that rotates within the catheter imaging lumen. The method includes applying pressure to push the medium into the lumen and / or vacuum to draw the medium out of the lumen, and sealing the medium within the catheter using a flexible seal and plug.

Description

Technical Field

[0001] Reference to Related Applications This application claims the benefit of U.S. Provisional Application No. 63 / 459,312, filed Apr. 14, 2023, entitled "Systems and Methods For Flush-Less Intravascular Ultrasound Catheter" and U.S. Provisional Application No. 63 / 546,091, filed Oct. 27, 2023, entitled "Systems and Methods For Flush-Less Intravascular Ultrasound Catheter", each of which is hereby incorporated by reference in its entirety.

[0002] In some embodiments, the present disclosure relates to the field of ultrasound, such as using ultrasound for diagnostic and imaging applications for medical purposes. Intravascular ultrasound (IVUS) imaging is provided in a plurality of embodiments.

Background Art

[0003] Ultrasound transducers, including those used for intravascular imaging, use one or more ultrasound elements to emit and / or receive acoustic signals through an acoustic coupling medium, such as a gel or fluid, for imaging and / or treating tissue. Some standard IVUS catheters rely on flushing the inner lumen with fluid to remove or reduce air bubbles around the ultrasound transducer to improve clarity for satisfactory imaging.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Imaging and diagnosis of intravascular tissues and blood may be important, for example, in identifying irregularities, diseases, and / or injuries for medical treatment, which can improve patient outcomes. Image clarity may be important, for example, for proper identification of lesions, plaques (e.g., hard plaques, soft plaques, fragile plaques, calcified plaques, fibrous fatty plaques, substantially non-calcified plaques), thrombi, blood clots, embolisms, calcium accumulations, dissections, and measurement of these abnormalities. Imaging such as IVUS imaging may be useful in planning and guiding treatment choices in interventional cardiology, vascular surgery, and interventional radiology throughout the body, from the heart to the peripheral vascular system. In some embodiments, intravascular image-guided percutaneous interventions in arteries and veins are achieved by using the IVUS imaging enhancements described herein. In some embodiments, the IVUS imaging system comprises an imaging console (e.g., a workstation, computer, processor), a user interface (e.g., a tablet, controls), one or more displays, and an IVUS imaging catheter inserted into the patient's vascular system to image vascular anatomical structures. In some embodiments, the imaging console is a tablet, workstation, computer, display, user interface, or other control device that may include a processor and / or software. A catheter interface module (CIM) optionally connects the catheter to the console, or the catheter can optionally connect directly to the console. In standard IVUS catheters, which require flushing with saline or a similar fluid through an internal imaging lumen containing a rotating imaging core with a transducer, air bubbles around the imaging transducer in the lumen can interfere with the transmission and reception of ultrasound, resulting in blurred or poor-quality ultrasound images. Therefore, some embodiments described herein are designed to address the air problem by providing catheters pre-filled in an air-free manner within an acoustically coupled medium (e.g., a coupling medium, medium, liquid, fluid, gel, etc.). [Means for solving the problem]

[0005] In some embodiments, the technologies described herein, including, for example, IVUS flashless technology, are used in conjunction with other medical imaging systems (such as cardiac catheterization laboratory systems) to provide cardiologists with an integrated healthcare portfolio. In some embodiments, the integrated or otherwise coordinated platform can improve workflows between various imaging systems, including, for example, X-ray systems. In one embodiment, stent placement and other procedures (e.g., thrombectomy, clot recovery, balloon placement, etc.) are optimized using the IVUS technologies described herein in conjunction with X-ray, external ultrasound, and / or other non-IVUS technologies.

[0006] In some embodiments, the IVUS technology described herein is used in conjunction with other catheter-based imaging procedures and / or non-catheter-based imaging procedures. These imaging procedures may include ultrasound, X-ray, computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), PET-CT, fluoroscopy, endoscopy, angiography, optical coherence tomography, in vivo microscopy, 2D imaging, 3D imaging, and the like. Some embodiments described herein utilize synchronized operation, imaging, and / or measurement from two, three, or more imaging modalities (e.g., ultrasound, X-ray (including radiography, fluoroscopy, angiography, venography, etc.), magnetic resonance, PET scan, optical imaging (e.g., optical coherence tomography, light, laser imaging, etc.)). Multimodality synergies between IVUS and one or more additional imaging systems are achieved in some embodiments and include, for example, improved visualization and image quality, reduced procedure time, improved accuracy of stent positioning and vascular measurements, improved workflow and reliability, and other advantages. Multimodal systems including IVUS can be used, for example, to enable cardiologists to diagnose and / or treat vascular occlusions and other defects, thereby improving patient cardiac outcomes while reducing the overall cost burden on the healthcare system through efficient and effective integration with IVUS. Various embodiments of IVUS technology described herein can be used to obtain more robust images of vascular and organ structures (such as cardiac structures).

[0007] In some embodiments, the proximal connector hub (i) latches securely to the CIM or console and is easily released during removal, (ii) mates with the CIM or console receptacle and is electrically connected, (iii) mates with the motor drive shaft in the CIM or console receptacle and maintains concentric rotation of the rotating shaft, (iv) seals the acoustic coupling medium in the catheter lumen distal to the seal, and / or (v) supports a filling port for the acoustic coupling medium. In some embodiments, the drive shaft may optionally comprise a drive cable, a drive coil, a drive system, and / or a drive actuator. Some embodiments provide a rigid proximal connector hub having a seal as part of the catheter (e.g., a flexible seal, in some embodiments, a flexible seal whose flexibility is elastic, malleable, bendable, modifiable, adjustable, accommodating, adaptable, flexible, pliable, moldable, and / or elastic) to rotate the inner imaging core without leakage of the medium while supporting the sealed acoustic coupling medium and to prevent air from entering the imaging lumen. In some embodiments, one or more seals are located within a rigid connector hub. In some embodiments, the seals are not located within a flexible structure such as a flexible catheter or flexible lumen. In various embodiments, the seals may be located within a rigid structure. Flexible seals (e.g., O-rings, other circular seals, or seals of other shapes) surround the drive shaft (e.g., drive cable, drive coil, drive system, drive actuator) of a rotating imaging core within a rigid proximal connector hub, holding the medium in the lumen connected to the hub while the core rotates. In some embodiments, the seals remain stationary relative to the drive shaft, the seals remain stationary relative to the catheter wall, and / or do not move with or relative to the drive shaft and catheter wall (e.g., without translational or linear motion). In some embodiments, the seals are spaced away from, separated from, and do not contact with the motor.The circular seal may be compressed onto the drive shaft with sufficient force to prevent leakage, while the motor (e.g., connected to an imaging console) can rotate the inner imaging core at a rate that supports a high imaging frame rate. Examples of sealing materials include elastic polymers and similar materials such as nitrile, ethylene propylene rubber, and fluorocarbons. The components and features of the hub may be arranged to secure the flexible seal between the connector hub and the rotary drive shaft, for example, a seal housing and / or seal cap. The inner diameter / surface of the seal housing may be precisely dimensioned to ensure that appropriate compression is applied to the flexible seal, allowing the drive shaft to rotate without excessive friction, while simultaneously preventing the medium from leaking proximal through the flexible seal. To prevent leakage around the flexible seal, an adhesive may be optionally applied to the outer circumference of the flexible seal. The flexible seal may be assembled inside a rigid proximal connector hub to ensure accurate mating. In some embodiments, this is advantageous over placing the seal inside a flexible catheter or similar catheter body / lumen, as flexibility can contribute to media leakage or air intrusion during use. During normal operation in a typical clinical environment, according to some embodiments, the pressure difference on both sides of a flexible seal can generally be small, so there is little force pushing the media or drawing in air. However, outside of the clinical setting, such as during product transport, catheters may be exposed to extreme temperature and ambient temperature fluctuations. When exposed to extreme temperature drops or rises, the volume of the binding medium decreases or increases, respectively, and then returns to its default volume after exposure to extreme temperatures. This volume change typically requires some sealing force to prevent air from being drawn into the internal imaging lumen or fluid from leaking out of the internal imaging lumen, in some embodiments. Air entering the lumen can move to the distal transducer of the rotating imaging core and degrade image quality. A double-seal housing may be preferred in one embodiment for precise assembly and sealing, but a single housing on the proximal side alone may also be used.According to some embodiments, the filling port is contained within a rigid proximal connector hub and is sealed after the catheter lumen is filled with a medium. The filling port may be configured to facilitate connection to a filling device. After filling the catheter lumen, the filling port may be closed, for example, with a seal, stopper, plug and / or adhesive, to prevent air intrusion. According to some embodiments, the techniques described herein, including, for example, IVUS flashless technology, include a reversible flash port seal that allows for product modification after inspection (e.g., checking for remaining air bubbles or image quality) and optionally before permanent sealing. In some embodiments, the filling and / or flashing procedure can be repeated with the reversible port seal until satisfactory results are obtained (e.g., removal of air bubbles). In one embodiment, the seal is reversible. In one embodiment, the seal is permanent. In some embodiments, the filling port may be temporarily sealed to facilitate inspection and permanently sealed after confirming that the filling process has been successful. In some embodiments, the temporary seal of the filling port can be removed to facilitate further fluid filling process steps. In one embodiment, the filling port has a most proximal inlet juxtaposed with a flexible seal to help remove all air bubbles during the filling process. In some embodiments, a portion of the acoustically coupled medium exits the imaging lumen of the IVUS catheter (e.g., during the filling process) through a distal port (e.g., an exit port, exhaust port, vent, hole, aperture, channel, or opening). In some embodiments, the distal port extends through the catheter wall perpendicular to the longitudinal axis of the catheter and does not extend along a distance within the catheter wall along the longitudinal axis of the catheter.

[0008] Methods for sealing the outlet port after filling the imaging lumen are also provided in embodiments herein. In one embodiment, the distal plug is attached to a removable wire. In some embodiments herein, designs and methods for venting and sealing the inner imaging lumen (e.g., venting and sealing the outlet port and filling port during or after filling the inner imaging lumen) are also provided. In one embodiment, the distal tip is formed by a plug fused to the distal end of the imaging lumen to seal the imaging lumen. A removable wire is positioned next to the plug during the fusion process and subsequently removed, effectively forming a narrow channel for venting air during the filling process. The removable wire may include, for example, NiTi (nitinol), stainless steel, or other wires. The wire size may be configured to form an effective vent that can be easily sealed after the filling process, for example, by heat or adhesive. In one embodiment, the wire is in the size range of 0.005 inches to 0.010 inches (e.g., 0.005, 0.006, 0.007, 0.008, 0.009, 0.010 inches and overlapping values ​​and ranges within those).

[0009] According to some embodiments, once all bubbles are removed from the imaging lumen when air is removed from the vent, the filling process is complete and, after inspection for the absence of bubbles, the vent and distal plug are sealed in a heating process that reflows the material together and / or a small amount of adhesive is inserted into the vent. In one embodiment, the distal tip may be formed at the distal end of the imaging lumen with a distal plug and a removable wire. The removable wire may be, for example, NiTi (nitinol), stainless steel, or other materials (e.g., metal, alloy, rigid and / or flexible wire). According to some embodiments, (i) a wire is fed through the lumen exiting the outlet port, and the distal plug floats loosely within the distal compartment of the lumen; (ii) the filling process is completed when all bubbles are removed from the lumen as air is removed from the outlet port; (iii) once inspected for the absence of bubbles, the distal plug is bonded to the lumen wall in a heating process that reflows the material together, and / or a small amount of adhesive is inserted into the outlet port to bond the plug to the lumen wall. After the distal plug is bonded to the catheter lumen, the wire can be easily removed from the plug. A colorant is added before the filling process is initiated, thereby aiding leak detection and bubble identification. The colorant may, if necessary, improve the manufacturing process by adding optical contrast to aid in the identification of the medium and bubbles.

[0010] In some embodiments, catheters optimized for angiography are configured for superior pushability, traceability, and transverseness for the peripheral arterial and venous vascular systems. In some embodiments, one or more of the following features are provided:

[0011] Pushability: In some embodiments, the catheter has excellent pushability that avoids bending and sufficient column strength to pass through tortuous bends and occlusions in the blood vessel without buckling, excessive bending, or crushing in any part of the catheter (e.g., adjacent portion or (e.g., ability to traverse occlusion or stenosis)). Material properties in some embodiments (e.g., balance of stiffness and flexibility, durometer of various segments), dimensional properties (e.g., larger dimensions such as diameter and thickness) increase column strength and improve pushability and bending resistance.

[0012] Traceability: In some embodiments, the catheter has excellent traceability in terms of its ability to follow the guidewire through meandering bends in the vascular system, and has sufficient flexibility and strength to move along the guidewire and advance along the guidewire to a target position in the vascular system. Hydrophilic coatings in some embodiments help reduce friction with the guidewire and surrounding luminal tissue. In various embodiments, the hydrophilic coating is on the outer and / or inner surface of the catheter (e.g., inside the lumen). In some embodiments, the hydrophilic coating is not on the outer surface of the catheter. In some embodiments, the hydrophilic coating is not on the inner surface of the catheter (e.g., inside the lumen).

[0013] Transverseness: In some embodiments, the catheter has excellent transverseness to traverse occlusions, restrictions, and stenosis within the vascular system, such as sites with tissue occlusion (e.g., stenosis) and / or implant occlusion (e.g., stents, balloons, etc.). According to some embodiments, transverseness is enhanced by one or more of the following: (i) distal tip design (e.g., sharp enough to navigate occlusions, etc., and blunted to avoid snagging on occlusions), (ii) material properties (e.g., balance of rigidity and flexibility, durometer of various segments, etc.), and / or (iii) dimensional properties (e.g., larger dimensions such as diameter and thickness increase column strength). In one embodiment, low durometer near the distal tip is provided for flexibility to navigate tortuous anatomical structures and occlusions. In one embodiment, a region is provided in which the durometer changes gradually in a manner sufficiently proximal to push the catheter while avoiding bending. A single durometer and / or flexibility may be kept constant along specific or all parts of the device.

[0014] Several embodiments described herein provide an IVUS catheter having a proximal connector hub assembly that facilitates an improved process for filling the IVUS catheter with an acoustically coupled medium. In some embodiments, the inner lumen of the IVUS catheter is configured as an imaging lumen and includes an imaging transducer. In some embodiments, the filling port is designed to seal the acoustically coupled medium around the imaging lumen and transducer. In various embodiments, the acoustically coupled medium preparation process, the coupled medium filling equipment and process, and the structural components consist of design features that assist in removing air from the catheter body. In some embodiments, the proximal connector hub assembly may include a filling port, a filling port cap, and a filling port cover. The filling port may accept a filling port cap, which may be an elastomer seal component or a rigid plastic cap. The filling port cap may be mated with a filling adapter of a filling nozzle that can be used to fill the IVUS catheter with an acoustically coupled medium. In one embodiment, if the filling port cap is an elastomer seal, the filling nozzle may include a needle that punctures the seal and fills the catheter. Once the IVUS catheter is filled, the filling nozzle and filling port adapter can be disengaged from the filling port cap, thereby drawing the acoustic coupling medium into the filling port cap and preventing air from entering the inner imaging lumen of the IVUS catheter. In some embodiments, the inner lumen is configured as the imaging lumen. In some embodiments, the imaging lumen is the inner lumen. Once the IVUS catheter is filled, the filling nozzle and / or filling port adapter may be disengaged from the filling port cap and subsequently covered by the filling port cover. In some embodiments, the proximal connector hub assembly may include a proximal connector hub having a filling port, a filling port valve cap, and a filling port cover. The filling port can accept the filling port valve cap.The filling port valve cap can be mated with a filling adapter for a filling nozzle that can be used to fill the IVUS catheter with an acoustically coupled medium. Once the IVUS catheter is filled, the filling nozzle and filling port adapter can be disengaged from the filling port valve cap, thereby drawing the acoustically coupled medium into the filling port valve cap and preventing air from entering the internal imaging lumen of the IVUS catheter. In some embodiments, the catheter connector hub (i) latches securely to the catheter interface module and dislatches easily during removal, (ii) mates with the catheter interface module receptacle and connects electrically, (iii) mates with the motor drive shaft within the catheter interface module receptacle and maintains concentric rotation of the rotating shaft, (iv) seals the acoustically coupled medium in the catheter lumen distal to the seal, and / or (v) supports the filling port for the acoustically coupled medium. In some embodiments, the drive shaft may optionally include a drive cable, drive coil, drive system, and / or drive actuator.

[0015] The proximal connector hub may include strain relief components that can reduce or prevent bending and excessive local strain within the IVUS catheter. According to some embodiments, the proximal hub connector may also include a seal, a drive bushing, a drive hub, a drive hub pin, and / or an electronic identification (EID) printed circuit board (PCB). The drive bushing can reduce wobble and / or uneven rotational strain (NURD) and prevent leakage of the acoustic coupling medium by maintaining uniform friction around the inner diameter of the seal.

[0016] Several methods described herein provide degassing of an acoustic coupling medium and filling of an IVUS catheter with the degassed acoustic coupling medium, which in some embodiments advantageously eliminates the need for the user to prepare and flush the lumen around the internal imaging core with fluid. Furthermore, some embodiments of the methods described herein advantageously prevent the introduction of air into the acoustic coupling medium during filling, which improves the quality of images captured by the IVUS catheter and reduces procedure time by eliminating the need to replenish or replace the IVUS catheter, among other advantages described herein.

[0017] In some embodiments, the degassing process involves exposing the acoustic fluid to a vacuum or low pressure for a period of time. In one embodiment, the degassing process can be initiated by providing a degassing device. The degassing device may include a container, a vacuum pump, a magnetic stirring plate, a hot plate, and / or a syringe. The container may be connected to the vacuum pump via a tubing section and a first valve, such as a directional valve. The container may be connected to the syringe via a second valve, such as a stopcock valve. The acoustically coupled medium may be placed in the container and held for a first period. The first period may be a set period or may continue until the acoustically coupled medium reaches an air saturation threshold. After the first period, the acoustically coupled medium may be held at vacuum pressure for a second period. The second period may be a set period, as described later, or may continue until the acoustically coupled medium reaches a desaturation threshold. Once the acoustically coupled medium reaches a desaturation threshold, the medium may be transferred to the syringe. In one embodiment, the medium may be transferred to the syringe via a tubing section and a second valve. In one embodiment, the magnetic stirring plate is a hot plate, and the degassing process also includes heating the acoustic coupling medium to reduce the viscosity of the fluid and facilitate the subsequent filling process.

[0018] The IVUS catheter may be filled with a degassed acoustic coupling medium. In some embodiments, the filling process can be initiated by providing an IVUS catheter filling device which may include a fluid pump such as a syringe pump device, a catheter heating plate, and / or a microscope. The IVUS catheter may be placed in the catheter heating plate and heated to a target catheter temperature. The catheter heating plate may include a notch for receiving the IVUS catheter. The notch may be "S" shaped, spiral, a straight path, etc., and may be molded based on one or more characteristics of the IVUS catheter.

[0019] The syringe pump device can accept syringes filled with degassed acoustic coupling medium. The syringe pump device may include a syringe pump, a syringe heating component (e.g., syringe jacket), a pressure gauge, at least one tubing section, a pump, and / or a three-way valve. The syringe pump can accept the syringe, and the syringe heating component is positioned around the syringe and can heat the syringe to a target temperature in the range of 35°C to 80°C (e.g., 35°C, 37°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C and overlapping ranges and values ​​therein). The syringe pump can discharge the acoustic coupling medium from the syringe through the pressure gauge into the tubing section. In some embodiments, the syringe pump can discharge the acoustic coupling medium at a target delivery rate, e.g., 0.4 mL / min. The delivery rate can be modified based on whether the pressure in the syringe pump device or IVUS catheter exceeds a pressure threshold, for example, 80 psi. In some embodiments, the syringe pump can discharge the acoustically coupled medium at a target filling pressure.

[0020] The acoustic coupling medium can pass through the tubing via a valve, such as a three-way valve, to the pump. The pump can be connected directly or via a filling nozzle and / or filling adapter to the filling port of the proximal connector hub of the IVUS catheter. The pump can fill the catheter imaging lumen by drawing / pushing the acoustic coupling medium from the tubing and / or syringe into the proximal connector hub of the IVUS catheter. The pump can also push air out of the imaging lumen of the IVUS catheter in some embodiments using an air vent in the catheter, for example, as described herein.

[0021] Some embodiments described herein provide an IVUS catheter having one or more features that allow the catheter to be more easily filled with an acoustically coupled medium while minimizing the risk of air being introduced into the medium and / or the catheter imaging lumen. The IVUS catheter may include an imaging core located within a catheter jacket. The imaging core may include a cable-connected transducer coupled to a transducer housing and a transducer housing coupled to a coil via a coupling in the imaging lumen. A drive shaft may be mounted proximal to the coil. The transducer, transducer housing, and / or coupling may include one or more apertures according to some embodiments. The drive shaft may also include one or more apertures according to some embodiments. The IVUS catheter may include a first gap in the lumen between the imaging core and the coil, and a second gap between the coil and the catheter jacket. According to some embodiments, the cross-sectional area of ​​the first gap may be much smaller than the cross-sectional area of ​​the second gap. Advantageously, the difference in cross-sectional area of ​​one or more apertures and / or first and second gaps arranged throughout the IVUS catheter reduces resistance to the medium flow for removing air inside the coil within the IVUS catheter, improving the speed and efficiency at which the IVUS catheter can be filled, improving air bubble removal and making it more effective. This can optionally improve the overall quality of the IVUS images captured by the IVUS catheter. In some embodiments of the filling process to help move air from the internal imaging lumen of the catheter, the filling of the acoustically coupled medium may be carried out while rotating the internal core at a target speed such as 1000 rpm ± 100 rpm. The target speed can be changed if air is introduced into the system during filling. For example, the target speed may be reduced if air is introduced.

[0022] Several embodiments described herein provide an IVUS catheter having a rotating internal imaging core sealed in a medium within the imaging lumen, which advantageously eliminates the need for the user to prepare the lumen around the internal imaging core and flush it with fluid. Furthermore, IVUS catheters according to various embodiments do not require a telescopic section connected to an electric unit to enable imaging of the vascular system using a rotating imaging core, which simplifies the IVUS catheter design. In some embodiments, the catheter does not have a telescopic section that moves along the longitudinal axis of the catheter. In some embodiments, the catheter does not have a movable or plunger or a movable seal. Several embodiments of methods for ensuring that the IVUS catheter is filled with a binding medium that supports imaging without air interfering with high-quality imaging are also disclosed.

[0023] In various embodiments, the catheter components include a rapid-exchange (RX) guidewire lumen or an over-the-wire (OTW) guidewire lumen. In some embodiments, catheter components incorporating an RX guidewire lumen or an OTW guidewire lumen are provided. In one embodiment, the catheter also includes an internal imaging lumen supporting an imaging core having a rotary drive shaft and a distal house transducer. The imaging lumen may be filled with a binding medium (e.g., liquid, fluid, gel, etc.) with good acoustic properties. A suitable medium is, for example, a liquid in one embodiment, because it may be easier to fill the lumen and remove air from the liquid. IVUS catheters that come into contact with blood may optionally be biocompatible and sterilizable. According to some embodiments, the binding medium with good acoustic properties may be biocompatible and sterilizable because there may be a risk of the medium entering the blood if there is leakage within the catheter. In one embodiment, the medium with good acoustic properties may have sound density and velocity values ​​similar to those of the catheter jacket material in some embodiments. Large differences in acoustic density or velocity between the medium and the catheter jacket can lead to undesirable strong acoustic reflections and refractive acoustic pulses, potentially degrading image quality. In some embodiments, the acoustic coupling medium has a sound velocity value configured for improved lateral performance. In one embodiment, the geometric shape of the rotating element catheter can include a focusing lens for ultrasound, formed by a gently convex circular layer of material on the transducer surface having a sound velocity slightly lower than the material being imaged. In one embodiment, a high-sound-velocity, tightly curved shell (catheter body) and inner material (binding medium) can be selected to be close to, and possibly even higher than, the material being imaged. In one embodiment, the geometric design of a rotating catheter having a thin, relatively high-velocity catheter body and its internal binding medium can be configured to have a considerably advantageous focusing effect. This embodiment can be configured to be unexpected and surprising, as the focusing lens for ultrasound is formed by a gently or slightly convex circular layer of material on the transducer surface having a sound velocity slightly lower than the material being imaged.In one embodiment, the high-velocity, tightly curved shell (catheter body) and inner material (binding medium) can be selected to be close to or even higher in velocity than the material being imaged. In some embodiments, the medium comprises one of polyethylene glycol (PEG), PEG with some water, water, saline solution, glycerin, and natural oil. The proportion of non-PEG components may be 80-20% (e.g., 80%, 70%, 60%, 50%, 40%, 30%, 20% and overlapping values ​​and ranges therein), and in certain embodiments, it may be in the range of 50-30% (e.g., 50%, 45%, 44%, 43%, 42%, 41%, 40%, 39%, 38%, 37%, 35%, 35%, 30% and overlapping values ​​and ranges therein), due to the latter having a lower tendency for dissolved gases. In some embodiments, the binding medium comprises one or more fluids.

[0024] Some embodiments provide a rigid proximal connector hub having a seal (e.g., a flexible seal, in some embodiments, flexible, resilient, malleable, bendable, modifiable, adjustable, accommodable, adaptable, flexible, pliable, flexible, moldable, and / or elastic) as part of the catheter to rotate an inner imaging core without leakage of the medium while supporting an enclosed acoustic coupling medium and to prevent air from entering the imaging lumen. The flexible seal (e.g., an O-ring, other circular seal, or seal of other shape) surrounds the drive shaft (e.g., a drive cable, drive coil, drive system, drive actuator) of the rotating imaging core within the rigid proximal connector hub, holding the medium in the lumen connected to the hub while the core rotates. The circular seal may be compressed on the drive shaft with sufficient force to prevent leakage, while a motor (e.g., connected to an imaging console) can rotate the inner imaging core at a rate that supports high imaging frame rates. Examples of sealing materials include elastic polymers and similar materials such as nitrile, ethylene propylene rubber, and fluorocarbons. The components and features of the hub may be arranged to secure a flexible seal between the connector hub and the rotary drive shaft, for example, a seal housing and / or seal cap. The inner diameter / surface of the seal housing may be precisely dimensioned to ensure that appropriate pressure is applied to the flexible seal, allowing the drive shaft to rotate without excessive friction, while simultaneously preventing the medium from leaking proximal through the flexible seal. To prevent leakage around the flexible seal, an adhesive may be optionally applied to the outer circumference of the flexible seal. The flexible seal may be assembled inside a rigid proximal connector hub to ensure accurate mating. In some embodiments, this is advantageous over placing the seal inside a flexible catheter or similar catheter body / lumen, as flexibility can contribute to medium leakage or air intrusion during use. During normal operation in a typical clinical environment, according to some embodiments, the pressure difference on both sides of the flexible seal can generally be small, so there is little force pushing the medium or drawing in air.However, outside of clinical settings, such as during product transport, catheters may be exposed to extreme temperature and ambient temperature fluctuations. Exposure to extreme temperature drops or rises causes the volume of the binding medium to decrease or increase, respectively, and then return to its default volume after exposure to extreme temperatures. This volume change typically requires some sealing force in some embodiments to prevent air from being drawn into the internal imaging lumen or fluid from leaking out of the internal imaging lumen. Air entering the lumen can move to the distal transducer of the rotating imaging core, potentially degrading image quality. A double-seal housing may be preferred in one embodiment for precise assembly and sealing, although a single housing on the proximal side may also be used. According to some embodiments, the filling port is contained within a rigid proximal connector hub and sealed after the catheter lumen is filled with the medium. The filling port may be configured to facilitate connection to the filling equipment. After filling the catheter lumen, the filling port may be closed, for example, with a seal, stopper, plug, and / or adhesive to prevent air intrusion. In one embodiment, the filling port has a most proximal inlet juxtaposed with a flexible seal to help remove all air bubbles during the filling process.

[0025] In some embodiments, a portion of the acoustically coupled medium exits the imaging lumen of the IVUS catheter through a distal port (e.g., an exit port, vent, hole, aperture, channel, or opening) (e.g., during the filling process). Methods for sealing the exit port after filling the imaging lumen are also provided in embodiments herein. In one embodiment, the distal plug is attached to a removable wire. In some embodiments herein, designs and methods for venting and sealing the internal imaging lumen (e.g., venting and sealing the exit port and filling port during or after filling the internal imaging lumen) are also provided.

[0026] In one embodiment, the distal tip is formed by a plug fused to the distal end of the imaging lumen, sealing the imaging lumen. A removable wire is placed adjacent to the plug during the fusion process and then removed, effectively forming a narrow channel for venting air during the filling process. The removable wire can include, for example, NiTi (nitinol), stainless steel, or other wires. The wire size may be configured to form an effective vent that can be easily sealed, for example, by heat or an adhesive, after the filling process. In one embodiment, the wire is in the size range of 0.005 inches to 0.010 inches (e.g., 0.005, 0.006, 0.007, 0.008, 0.009, 0.010 inches and overlapping values and ranges therein). According to some embodiments, when all air bubbles are removed from the imaging lumen when air is removed from the vent, the filling process is complete, and when it is inspected that there are no air bubbles, the vent and the distal plug are sealed by a heating process that reflows the materials together, and / or a small amount of adhesive is inserted into the vent. In one embodiment, the distal tip may be formed by a distal plug and a removable wire at the distal end of the imaging lumen. The removable wire can include, for example, NiTi (nitinol), stainless steel, or other materials (e.g., metals, alloys, rigid and / or flexible wires). According to some embodiments, (i) the wire is fed through the lumen exiting the exit port, and the distal plug floats loosely within the distal section of the lumen, (ii) when all air bubbles are removed from the lumen when air is removed from the exit port, the filling process is complete, (iii) when it is inspected that there are no air bubbles, the distal plug is joined to the wall of the lumen by a heating process that reflows the materials together, and / or a small amount of adhesive that joins the plug to the lumen wall is inserted into the exit port. After joining the distal plug to the catheter lumen, the wire can be easily removed from the plug. A coloring agent is added before the filling process is initiated, thereby assisting in leak inspection and air bubble identification. The coloring agent may, if necessary, improve the manufacturing process by adding an optical contrast that aids in the identification of the medium and air bubbles.

[0027] In some embodiments, methods are also provided for sealing a medium, such as a fluid, within the lumen of the IVUS catheter to prevent the formation or trapping of air bubbles during the filling process. A vacuum pump may be attached to the distal outlet port to remove air from the catheter lumen, and then the inlet port valve may be opened to allow the medium to be drawn into the lumen. A pump can also be used to push the medium in place of a vacuum pump, or in combination with a vacuum pump to draw in the medium. A pump (e.g., a peristaltic pump or other pump) is an example of a useful pumping mechanism for pushing.

[0028] In some embodiments, filling the imaging lumen with a medium using a vacuum for retraction and / or a pump for intrusion can be complemented by degassing the medium before filling. Non-degassed medium is typically saturated with dissolved gases in the ambient environment, and these gases may escape from the solution during the filling process or during the device's shelf life, generating bubbles during and after the filling process, potentially interfering with imaging in use. These bubbles can adhere to surfaces, especially uneven surfaces, making it difficult to completely remove air from the catheter lumen. In some embodiments, the binding medium is degassed before retracting and / or intruding it into the lumen. In some embodiments, exposure to ambient air is further minimized before the filling process begins. A degassed liquid can remain unsaturated for a certain actual period (the actual filling period), during which time the catheter lumen can be filled. This can reduce the risk of air escaping from the solution during the filling process and, furthermore, can absorb any bubbles present during the process. Absorption of bubbles using a properly degassed medium can be an effective mitigation, as these bubbles remain in the solution and do not reappear later. In a properly degassed medium, the internal pressure of existing bubbles can selectively dissolve the internal air into the medium, thereby eliminating the trapped bubbles. In one embodiment, selective degassing of the medium reduces the number of visible bubbles in the medium.

[0029] The maximum period for which the solution maintains its unsaturated state, and thus the period available for the filling process, depends in some embodiments on the type of medium, the degassing procedure, and the post-treatment medium handling container. In one embodiment, the maximum period can be determined experimentally using an oxygen sensor placed in a representative medium to measure the oxygen in the medium compared to the oxygen fraction in ambient air. For example, in the case of PEG400, a fluid with a viscosity of about 100 cP when properly degassed, the actual filling period is less than 2 hours, supporting a manufacturing process that can be used to fill the lumen within 1 hour immediately after the degassing step is completed.

[0030] For example, heat can be applied to the medium during the medium filling process by heating the container used to degas the binding medium and / or the tubing used to fill the catheter lumen and / or the catheter itself. Heat can reduce viscosity, which reduces the time it takes to fill the catheter lumen, and can further reduce dissolved gases in the medium. Above ambient temperature, the viscosity of the medium decreases, and as the temperature rises, the amount of dissolved gas decreases, thus further improving the filling results. In various embodiments, the binding medium is heated to a temperature in the range of 60 to 100°C (e.g., 60, 65, 70, 75, 80, 85, 90, 95, 100°C and overlapping values ​​and ranges within that range). In one embodiment, 60°C is a useful temperature because it can prevent burns if someone touches the catheter or equipment. Higher temperatures, such as below 100°C, may be useful if precautions are taken to prevent accidental contact during the filling process. Bubbles can also be present inside the imaging lumen of the catheter, for example, inside the imaging core, or inside other cavities or interfaces inside the proximal hub connection to the imaging lumen. These other cavities may be difficult or impossible to inspect for air bubbles during and after the filling process. As a result, air bubbles may be present after the filling process is complete, undetected, and appear during subsequent clinical use. Several processes for filling the catheter by degassing the binding medium as described in the embodiments herein can significantly reduce the risk of undetected air bubbles appearing and degrading image quality. In a rotating IVUS catheter, a drive cable or coil and electrical cables inside the drive cable or coil may be present. The space inside and around the drive cable along the entire length of the catheter is a space where air may not be easily and completely removed, so degassed binding medium helps remove air from hidden cavities.

[0031] In some embodiments, agitation of the catheter lumen and movement of the internal imaging core are performed to remove air from the lumen and other internal components during the filling process. Agitation may be achieved by vibration of the catheter and / or rotation of the internal imaging core. In some embodiments, the catheter is held vertically or at some positive angle above horizontal with the assistance of gravity to move the air bubbles upward from the exit port, in order to expel the bubbles and help visualize an acceptable filling process.

[0032] Visual inspection of the distal exit port of the catheter to completely remove all air bubbles can be used to indicate the cessation of the filling process and to signal a verified process based on its duration.

[0033] In some embodiments, an IVUS catheter is provided, which comprises (i) an elongated flexible member having a sealed lumen; (ii) a rigid proximal connector hub attached to the elongated member for connection to a console; (iii) an imaging core moving inside the imaging lumen, including a rotary drive shaft and a distal ultrasound transducer; and (iv) a flexible seal within the rigid proximal connector hub that seals the medium in the imaging lumen between the drive shaft and the flexible member, such that the acoustically coupled medium does not leak out of the lumen, air does not enter through the flexible seal, and the console receives signals to actuate the transducer to form an image. In some embodiments, the drive shaft may optionally include a drive cable, a drive coil, a drive system, and / or a drive actuator. Optionally, the distal end of the internal imaging lumen may include a distal port and a distal plug.

[0034] In some embodiments, the medium filling method includes (i) placing a flexible seal within a rigid proximal connector hub to be sealed with a binding medium in the lumen of an elongated flexible member, wherein the binding medium is biocompatible, sterilizable, and acoustically compatible; (ii) degassing the medium (fluid or gel) before filling the cavity to remove some dissolved gases from the medium; (iii) drawing and / or pushing the medium into the lumen under vacuum; (iv) sealing the inlet port; and (v) sealing the outlet port. In various embodiments, the medium is polyethylene glycol (PEG), PEG with some water, water, saline solution, glycerin, and / or natural oil.

[0035] Optionally, a method for filling the medium includes one or more of the following: pushing the medium by a pump, e.g., a peristaltic pump, syringe, or displacement pump; drawing the medium by a vacuum pump attached to the distal outlet port; introducing mechanical agitation to facilitate more effective air removal; vertical or non-horizontal orientation of the catheter to support effective air removal from the lumen assisted by gravity; heating the medium and / or the catheter lumen to facilitate air removal from the medium while reducing viscosity to speed up the filling process; and sealing the outlet port with a polymer plug, using heat to melt the polymer plug into the jacket or adhesive to join the interface.

[0036] In various embodiments, flashless rotating imaging cores, IVUS catheters are provided that operate immediately out of the package after a rigid proximal connector hub is inserted into the imaging console for improved ease of use. In one embodiment, the absence of a retractable catheter body eliminates the need for an additional motorized unit on the patient bench, improving ease of use and reducing the manufacturing cost of the catheter. In various embodiments, flashless catheters are provided that avoid leakage and air ingress, with improved reliability of the sealed binding medium. In some embodiments, intraluminal ultrasound imaging is achieved using the apparatus and methods described herein. Imaging and diagnosis of intraluminal (e.g., intravascular, luminal, gastrointestinal, esophagus, stomach, intestine, rectum, pancreas, sinuses, ureters, bladder, gynecological, etc.) tissues helps, in some embodiments, identify irregularities, diseases, and / or injuries for medical treatment to improve patient outcomes.

[0037] In various embodiments, a pre-filled IVUS device is provided that includes one or more seals to help prevent leakage of the acoustically coupled medium from the device. For example, a flexible seal may take into account the pressure difference present when filling the lumen or during transport, handling, and storage conditions at variable pressure and temperature. In various embodiments, a flashless IVUS catheter includes an imaging core with a rotating ultrasonic transducer connected to the distal end of a drive shaft. The drive shaft may optionally include a drive cable, drive coil, drive system, and / or drive actuator. The IVUS catheter may include a flexible elongated member containing a sealed lumen, which is designed to receive the rotating ultrasonic transducer and the acoustically coupled medium. The sealed lumen may include a proximal end, a distal end, and a flexible wall extending to a length between the proximal and distal ends. In various embodiments, the proximal end includes a proximal connector. Optionally, the distal end may include a distal port and a distal plug. An IVUS catheter may include an internal chamber, a medium-filling port, a distal interface, a proximal interface, and a rigid connector hub having a flexible seal. The medium-filling port may optionally be designed to insert an acoustically coupled medium into the rigid connector hub to fill a sealed lumen. The distal interface may be configured to connect to the strain relief of the proximal connector of the sealed lumen. Optionally, the proximal interface may be configured to connect to a console that rotates a drive shaft. In some embodiments, the imaging console is a tablet, workstation, computer, display, user interface, or other control device that may include a processor and / or software. In some embodiments, the seal is distally connected to a seal housing connected to the proximal interface, the seal is proximal connected to the internal chamber of the rigid connector hub, the drive shaft extends distally through the seal, and the sealed lumen communicates with the seal, the internal chamber, and the distal plug through the sealed medium.

[0038] In some embodiments, an ultrasound catheter is provided that includes one or more seals that allow air to escape while enabling the acoustic coupling medium to completely fill the cavity around the ultrasound transducer, thereby reducing or eliminating air bubbles (this provides a clearer image, as air bubbles can interfere with the transmission of sound waves). In one embodiment, an apparatus is provided (including, but not limited to, a flushless IVUS catheter) that includes an ultrasound transducer connected to a drive shaft and an elongated member including at least one sealed lumen, the sealed lumen configured to receive the ultrasound transducer and the acoustic coupling medium, and the sealed lumen includes a proximal end, a distal end, and one or more walls extending to a length between the proximal and distal ends. Optionally, the proximal end includes a proximal connector, and the distal end includes one or more distal ports and one or more distal plugs. The rigid connector hub may optionally include one or more internal chambers, one or more medium-filled ports, one or more distal interfaces, one or more proximal interfaces, and one or more seals. A medium-filling port may be configured to insert an acoustic coupling medium into the rigid connector hub to fill a sealed lumen. A distal interface may be configured to connect to the proximal end of an elongated member and the sealed lumen. The proximal interface may be configured to connect to a console, in one embodiment, which is configured to actuate a drive shaft, and the seal is distally connected to a seal housing connected to the proximal interface. According to one embodiment, the seal may be proximal to an internal chamber of the rigid connector hub, the drive shaft extends distally through the seal, and the sealed lumen communicates with one or more seals, one or more internal chambers, and one or more distal plugs through the sealed medium.

[0039] In various embodiments, the catheter includes an ultrasonic transducer connected to a drive cable and an elongated member having a lumen, the lumen configured to receive the ultrasonic transducer and an acoustic coupling medium, the lumen having a proximal end, a distal end and a wall extending to a length between the proximal and distal ends, the proximal end having a proximal connector, the distal end having a distal port and a distal plug, the rigid connector hub comprising an internal chamber, a distal interface, a proximal interface and a seal, the distal interface configured for connection to the proximal connector strain relief of the lumen, the seal distally connected to a seal housing connected to the proximal interface and the seal proximal connected to the internal chamber of the rigid connector hub, the drive cable extending distally through the seal and the lumen communicating with the seal, internal chamber and distal plug and the sealed medium.

[0040] Optionally, a seal housing is bonded to a connector hub, for example, via a seal port. A flashless IVUS catheter may also include a second seal housing, which is attached to the proximal interface. In one embodiment, a medium-filled port is configured to be sealed after delivery of the acoustically coupled medium. The distal plug may optionally comprise a removable wire extending through the distal port, be inserted into the proximal end of the lumen and configured to be retracted into the distal end of the lumen by the removable wire, be bonded to the distal port, be bonded to a portion of a flexible wall adjacent to the distal end, and be configured to be sealed by bonding the distal plug via heat and / or adhesive. The distal plug may be a polymer. Optionally, the binding medium is selected from the group consisting of one or more of polyethylene glycol (PEG), water, saline, glycerin, and oil (and combinations). The drive shaft may be rotatably actuated by an actuator adjacent to the proximal interface. Optionally, the imaging core may be electrically connected to a console via the drive shaft. For example, the console may include a processor configured to instruct actuators to rotate an imaging core, instruct a rotary transducer to generate an ultrasonic signal, receive a backscatter signal from the rotary transducer, and / or generate an ultrasonic image based on the backscatter signal.

[0041] In various embodiments, a kit is provided comprising one, some, or all of the following catheters, hubs, and connectors described herein, as well as instructions for use.

[0042] Artificial intelligence and / or machine learning (AI / ML) are used in some embodiments to enable and / or enhance image interpretation using the technologies described herein. In one embodiment, the system is adapted to high-definition (e.g., HD, UHD, HD+, etc.) image quality using acoustic and signal processing customized for peripheral vascular imaging with improved resolution and / or transparency. Some embodiments are configured for intravascular imaging using a platform optimized for peripheral and / or coronary vascular procedures, enabling improved image interpretation, intervention guidance, enhanced ease of use, and improved overall usability to streamline intraoperative and clinical workflows. In some embodiments, the system is made more user-friendly by a modern system with a simplified user interface and enhanced overall system functionality that leverages AI to streamline workflows and image interpretation. In some embodiments, the systems described herein, including, for example, an advanced intravascular ultrasound platform, leverage artificial intelligence (AI) to enable image interpretation, enhance overall system functionality, streamline workflows, and maximize clinical value. In some embodiments, advantageously, physicians do not need to spatially and temporally integrate (e.g., cognitively integrate) imaging data to fully interpret the clinical state. Instead, systems according to some embodiments described herein can leverage the power of AI with generational advancements to go beyond a single image interpretation. In some embodiments, the AI-driven engine may include a workstation that enhances image interpretation in a simplified workflow that improves overall usability, for example. In some embodiments, machine learning is used. In one embodiment, the AI-enabled processing power is designed to support real-time and on-demand image interpretation. The AI-driven workstation can provide a high-end processing and AI engine for advanced signal and image processing. In various embodiments, native image data capture provides superior image interpretation (e.g., identification and measurement of boundary detection, vessel size, vascular disease, dissection, plaque morphology, etc.).In some embodiments, the systems described herein provide simplified measurements through automated boundary detection (e.g., an AI algorithm automatically identifies boundaries such as lumens, blood vessels, tissues, lesions, and plaques). In some embodiments, the systems provide simplified measurements through semi-automatic boundary detection (e.g., the user can manually adjust or modify an automated AI algorithm that identifies boundaries such as lumens, blood vessels, tissues, lesions, and plaques, and the boundary selection is reconfigured based on the user's modifications). In one embodiment, AI plaque identification utilizes an AI algorithm to automatically classify and identify the type of plaque within the imaging area and provides user guidance regarding treatment options (e.g., color coding, icons, or text overlays can be used to indicate what types of conditions, such as plaques, may be present in the selected image). In some embodiments, the data-driven platform is designed to collect data and simplify image interpretation using AI processing capabilities that reduce the cognitive load on the user, supporting real-time and on-demand image interpretation to help (i) identify lumen size, (ii) visualize dissection, (iii) characterize disease morphology, (iv) identify and quantify stenosis location, and / or (v) identify true lumen. In some embodiments, image interpretation is used to identify thrombi, thrombosis, blood clots, embolism, plaque, calcium, tissue health, stent or balloon adhesion, and / or the "health" or condition of the stent or balloon. Image interpretation may include imaging to assess the quality and / or location of existing stent placement. Image interpretation may include identifying location relative to the lumen wall, and determining the level and / or quality of tissue grown in and around the stent or balloon.In one embodiment, using, for example, a bioabsorbable stent, image interpretation may include (i) evaluating the amount of stent dissolution, and (ii) determining whether the stent dissolution follows an expected collapse pattern (e.g., determining whether the level of collapse on one side of the stent is similar to that on the other side, and if not, whether the stent is dissolving faster than expected, which may indicate a problem associated with the stent placement or that the stent will not provide the expected structural support to the tissue). In one embodiment, high-fidelity ultrasound data is used to drive improved image generation and image interpretation with options to leverage artificial intelligence and / or machine learning. In various embodiments, catheters, devices, systems, and methods may be configured to use artificial intelligence algorithms to perform edge-based machine learning computations related to image and / or image analysis in order to identify one or more of tissue boundaries, plaque, calcium, thrombi, dissection, and / or stent adhesion.

[0043] In various embodiments, a method for filling an IVUS catheter with an acoustically coupled medium includes the steps of: connecting a source of the acoustically coupled medium to the catheter, wherein the IVUS catheter comprises a flexible elongated member and a rigid connector hub, the rigid connector hub comprising an inlet port and an internal chamber, and the flexible elongated member comprising a lumen, an ultrasound imaging core, and an outlet port; filling the lumen with the acoustically coupled medium through the inlet port; discharging a portion of the acoustically coupled medium through the outlet port; sealing the outlet port with a plug; and sealing the inlet port.

[0044] In various embodiments, a method for filling an IVUS catheter with an acoustically coupled medium includes the steps of: connecting a source of the acoustically coupled medium to the IVUS catheter, wherein the IVUS catheter comprises a flexible elongated member and a rigid connector hub, the rigid connector hub comprising an inlet port and an internal chamber, and the flexible elongated member comprising a lumen, an ultrasound imaging core, and an outlet port; filling the lumen with the acoustically coupled medium through the inlet port; discharging a portion of the acoustically coupled medium through the outlet port; sealing the outlet port with a plug; and sealing the inlet port.

[0045] Optionally, the method may include a step of degassing the acoustically coupled medium. For example, the lumen may be filled with the acoustically coupled medium, which includes forcing the acoustically coupled medium into the lumen under positive pressure at the inlet port, for example, by a peristaltic pump designed to push the acoustically coupled medium into the lumen under positive pressure at the inlet port. Optionally, the lumen may be filled with the acoustically coupled medium, which includes drawing the acoustically coupled medium into the lumen under vacuum pressure at the outlet port. The acoustically coupled medium may be biocompatible, sterilizable, and / or acoustically compatible.

[0046] In various embodiments, a method for filling an IVUS catheter with an acoustically coupled medium includes the steps of: providing an IVUS catheter comprising a flexible elongated member and a rigid connector hub, the rigid connector hub comprising an inlet port and an internal chamber, and the flexible elongated member comprising an internal lumen, an ultrasound imaging core, and an outlet port; filling the internal lumen with an acoustically coupled medium through the inlet port; discharging a portion of the acoustically coupled medium through the outlet port; sealing the outlet port with a plug; and sealing the inlet port.

[0047] In various embodiments, a method for filling an IVUS catheter with an acoustic coupling medium includes the steps of connecting a source of the acoustic coupling medium to the IVUS catheter, the IVUS catheter comprising a flexible elongated member and a rigid connector hub, the rigid connector hub comprising an inlet port and an internal chamber, and the flexible elongated member comprising an internal lumen and an ultrasound imaging core, filling the internal lumen with the acoustic coupling medium through the inlet port, and sealing the inlet port.

[0048] In various embodiments, the flashless IVUS catheter imaging core is mechanically connected to the drive shaft via a catheter interface module. Optionally, the catheter interface module includes an actuator configured to rotate the drive shaft and / or a transceiver configured to transmit and receive ultrasound pulses. According to some embodiments, the IVUS catheter may include one or more strain reliefs configured to prevent bending and excessive local strain within the IVUS catheter.

[0049] Optionally, a flashless IVUS catheter may include (i) a filling port cap configured to seal acoustic coupling medium into an imaging lumen sealed by an acoustic coupling medium filling port; (ii) a filling port valve cap comprising an open configuration for filling with acoustic coupling medium, and comprising sealing acoustic coupling medium into an imaging lumen sealed by an acoustic coupling medium filling port; and / or (iii) a filling port cover configured to be inserted into and seal the filling port cap or filling port valve cap. In one embodiment, the rigid connector hub includes a drive bushing positioned around the drive shaft. In some embodiments, the drive shaft may include one or more apertures configured to allow acoustic coupling medium and bubbles to flow through the drive shaft.

[0050] In some embodiments, a flashless intravascular ultrasound (IVUS) catheter comprises (i) an imaging core having a rotating ultrasonic transducer connected to a drive shaft, and (ii) a flexible elongated member having a sealed imaging lumen, the sealed imaging lumen configured to receive the imaging core having the rotating ultrasonic transducer and acoustic coupling medium, the sealed imaging lumen comprising a flexible wall extending to a length between the proximal and distal ends, the distal end comprising a distal port and a distal plug, and (iii) a rigid connector hub comprising an internal chamber, an acoustic coupling medium-filled port, a distal interface, a proximal interface, and a flexible seal, the acoustic coupling medium-filled port for filling the sealed imaging lumen. The system includes a rigid connector hub configured to insert an acoustic coupling medium into the rigid connector hub, the distal interface configured to connect to the proximal end of a sealed imaging lumen, the proximal interface configured for connection to a catheter interface module, the catheter interface module comprising a motor and electrical connections to a console, the console configured for controlling the rotational operation of a drive shaft, a flexible seal distally connected to a seal housing connected to the proximal interface, the flexible seal proximal connected to an internal chamber of the rigid connector hub, the drive shaft extending distally through the flexible seal, and the sealed imaging lumen communicating with the flexible seal, the internal chamber, and the distal plug via a sealed acoustic coupling medium.

[0051] In some embodiments, a method for filling an ultrasonic device with an acoustic coupling medium includes (i) connecting a source of the acoustic coupling medium to the ultrasonic device, the ultrasonic device comprising a flexible elongated member and a rigid connector hub, the rigid connector hub comprising an inlet port and an internal chamber, and the flexible elongated member comprising an inner lumen and an ultrasonic imaging core; and (ii) filling the inner lumen with the acoustic coupling medium through the inlet port and sealing the inlet port. In various embodiments, the method may include holding the acoustic coupling medium in the ambient environment for a first period (e.g., in the range of 30 to 300 minutes) and / or until the acoustic coupling medium reaches an air saturation threshold. The method may also include holding the acoustic coupling medium in a vacuum environment for a second period (e.g., between about 30 and about 120 minutes) to form a degassed acoustic coupling medium and / or holding until the acoustic coupling medium reaches a desaturation threshold. In various embodiments, the desaturation threshold is based on the air saturation threshold and is between approximately 5% or less of the air saturation threshold and approximately 50% or less of the air saturation threshold, and / or approximately 20% or less of the air saturation threshold. According to some embodiments, the method may include the steps of placing an IVUS catheter in a catheter heating plate and heating it to a target catheter temperature of 35°C to 80°C, and / or placing an acoustically coupled medium in a syringe and inserting the acoustically coupled medium into the inner lumen via a syringe pump device. The syringe pump device may include a syringe pump configured to discharge the acoustically coupled medium from the syringe at a target delivery rate such as 0.1 mL / min to 1.0 mL / min.

[0052] The syringe pump device may include a rotary motor configured to (i) rotate the imaging core to agitate and remove air from the sealed inner imaging lumen, and (ii) operate at a target speed (e.g., between 900 and 1100 rpm) which can be based on one or more of the internal pressure of the syringe pump device and the internal pressure of the sealed inner lumen, and / or the target speed may be adjusted based on one or more of the internal pressure of the syringe pump device exceeding a pressure threshold (e.g., 50 psi to 150 psi) or the internal pressure of the sealed inner lumen exceeding a threshold.

[0053] In some embodiments, the degassing system includes a container configured to receive an acoustic coupling medium, a vacuum pump configured to be in fluid communication with the container, a hot plate configured to heat the container, and a container configured to receive a degassed acoustic coupling medium, wherein the acoustic coupling medium is held in the container in the ambient environment for a first period, and the vacuum pump is configured to be in fluid communication with the container and to maintain the container at a vacuum pressure for a second period to convert the acoustic coupling medium into a degassed acoustic coupling medium. Optionally, (i) the first period is 30 to 300 minutes, (ii) the first period continues until the acoustic coupling medium reaches the air saturation threshold, (iii) the second period is 30 to 120 minutes, (iv) the second period continues until the acoustic coupling medium reaches the desaturation threshold, (v) the desaturation threshold is based on the air saturation threshold, (vi) the desaturation threshold is between approximately 5% or less of the air saturation threshold and approximately 50% or less of the air saturation threshold, (vii) the desaturation threshold is approximately 20% or less of the air saturation threshold, and (viii) the hot plate is magnetically stirred. (ix) a magnetic stirring mechanism configured to rotate a magnetic stirring bar, the magnetic stirring bar being placed in the acoustically coupled medium for one or more of a first period and a second period, the magnetic stirring mechanism being configured to rotate the magnetic stirring bar and generate a magnetic field for stirring the acoustically coupled medium, (x) a hot plate being configured to heat the acoustically coupled medium to a first target temperature during the first period, and / or (xi) a hot plate being configured to heat the acoustically coupled medium to a second target temperature during the second period.

[0054] In some embodiments, the catheter heating device includes an insulating layer, a heating layer positioned above the insulating layer and configured to heat an IVUS catheter to a target temperature, a catheter receiving layer positioned above the heating element and comprising a catheter notch, the catheter notch configured to receive an IVUS catheter, and a cover layer positioned above the catheter receiving layer. The catheter heating device may optionally include: (i) the target temperature being at least about 35°C to at least about 80°C; (ii) the shape of the catheter notch being one of an "S" shape, a spiral shape, or a linear shape; (iii) the shape of the catheter notch being based on one or more characteristics of the IVUS catheter; (iv) the catheter receiving layer comprising one of a metal, a metal alloy, and a metal composite; (v) the catheter receiving layer comprising a metal such as aluminum; and / or (vi) the heating element comprising one or more heating elements.

[0055] In some embodiments, a flashless intravascular ultrasound (IVUS) catheter comprises: (i) an imaging core comprising a rotating ultrasonic transducer disposed within a transducer housing, the transducer housing being connected to the distal end of a coil and drive shaft via a coupling; (ii) a flexible elongated member comprising a sealed imaging lumen, the sealed imaging lumen configured to receive the rotating ultrasonic transducer and acoustic coupling medium, the sealed imaging lumen comprising a proximal end, a distal end, and a flexible wall extending to a length between the proximal and distal ends, the distal end comprising a distal port and a distal plug; (iii) a rigid connector hub comprising an internal chamber, an acoustic coupling medium-filled port, a distal interface, a proximal interface, and a flexible seal; and (iv) one or more apertures disposed on one or more of the transducer housing, coupling, and drive shaft, wherein the acoustic coupling medium and bubbles are connected to the transducer housing, coupling, coil, and drive shaft. The system includes one or more apertures configured to allow flow through one or more of the ducts, an acoustic coupling medium filling port configured to insert acoustic coupling medium into a rigid connector hub to fill a sealed imaging lumen, a proximal interface configured for connection to a console, the console configured for controlling the rotational operation of the drive shaft, a proximal interface configured for connection to a catheter interface module, the catheter interface module configured to rotate the drive shaft via an actuator, the catheter interface module includes a transceiver configured to transmit and receive ultrasound-acoustic pulses, a flexible seal distally connected to a seal housing connected to the proximal interface, the flexible seal proximal connected to an internal chamber of the rigid connector hub, the drive shaft extending distally through the flexible seal, and the sealed imaging lumen communicating with the flexible seal, the internal chamber, and the distal plug through the sealed acoustic coupling medium.

[0056] In general, some embodiments described herein provide an ultrasound transducer adapted to be positioned within a blood vessel using a catheter for acoustic imaging. Images and / or measurements of the vascular anatomical structure of the treatment site can be created by querying the surrounding blood and tissue with ultrasound pulses generated by the ultrasound transducer and creating images of the blood and tissue based on the backscattered signals in response to the ultrasound pulses. The ultrasound pulses may be acoustically transmitted through an acoustic coupling medium, a catheter polymer jacket, travel through the blood and tissue, be continuously backscattered to the transducer, and then return through the catheter jacket and coupling medium, and finally received by the transducer. In particular, intravascular ultrasound imaging can create 360° cross-sectional images of blood and tissue from within the vascular system based on the backscattered acoustic signals in response to the ultrasound pulses.

[0057] The systems and methods described herein, according to several embodiments, aim to produce improved intravascular ultrasound images. More specifically, in some embodiments, the systems and methods described herein produce intravascular ultrasound images that are not degraded by air bubbles through the incorporation of a sealed acoustic coupling medium. In various embodiments, the IVUS catheter reduces or eliminates the need for the user to flush the imaging core with fluid. This flushing requires valuable procedure time to ensure that air bubbles are reduced, removed, or eliminated from the lumen of the IVUS catheter. In one embodiment, the imaging core is an internal imaging core. In some embodiments, the IVUS catheter may be fixed length or may have a rotating imaging core with a sealed and enclosed acoustic coupling medium. In various embodiments, the coupling medium is a fluid, liquid, and / or gel. In some embodiments, a liquid coupling medium is easier to fill the lumen and minimize air bubbles. In some embodiments, the IVUS catheter does not require a telescopic section connected to an electric unit to enable imaging of the vascular system with a rotating imaging core. Methods for ensuring filling with a coupling medium that can support imaging without air interfering with high-quality imaging are also disclosed.

[0058] In various embodiments, an IVUS catheter includes a rotational and / or translational imaging core assembly within a polymer jacket. The transducer can translate and / or rotate within the distal lumen of the catheter jacket, and a binding medium, such as a liquid or gel, supports the transmission and reception of ultrasound pulses by the transducer in one embodiment. Without a binding medium, air may be present between the transducer and the catheter jacket, which can hinder sufficient energy transfer into the patient's blood vessels and degrade image quality.

[0059] In various embodiments, IVUS uses ultrasound only for imaging (no treatment). In various embodiments, IVUS uses ultrasound only for treatment (no imaging). In various embodiments, IVUS uses ultrasound for both imaging and treatment. According to some embodiments, one or more imaging techniques described herein can be combined on the same catheter as one or more treatment elements, such as an integrated ultrasound imaging element positioned at or near (or along) the tip of the thrombectomy device. The thrombectomy device may also be a separate device delivered before, between, or after the imaging device. The thrombectomy device may be a mechanical clot recovery device, a clot aspiration device, or a combination of clot recovery and aspiration. In some embodiments, neurovascular, coronary, and pulmonary clots are treated using the ultrasound imaging devices and methods disclosed herein in conjunction with a clot treatment device (either integrated or separate). The clot treatment device may also include non-mechanical devices, such as dissolution or other drug delivery and energy delivery devices, for example, to break up / remove clots or to restore blood flow. Combinations of two, three, or more therapies in combination with the IVUS imaging techniques described herein are also provided (e.g., destruction of blood clots by ultrasound or laser with a dissolving agent). According to some embodiments, the integrated IVUS and therapeutic catheter or probe may also be used to restore blood flow not caused by blood clots.

[0060] In various embodiments, the IVUS catheter is configured to image tissue and / or plaque (e.g., one or more of hard plaque, soft plaque, fragile plaque, calcified plaque, or substantially non-calcified plaque) (either alone or in combination with treatment). In various embodiments, the IVUS catheter is configured to image thrombi. In some embodiments, the techniques described herein are used for one or more of the following: thrombus identification, dissection, calcium severity, vascular measurements, and / or pre- and post-procedure planning. In some embodiments, the techniques described herein are used to guide stent sizing, identify stent placement, attachment, and / or expansion, assess lesion morphology, vascular wall thickening, loss of lumen patency, and / or vascular dysfunction, quantify plaque loading, identify complications from the procedure, and / or assess stent failure with stent thrombosis or intrastent restenosis. The techniques described herein can distinguish lipids, calcified plaque, and tissue proliferation. In many embodiments, better imaging detail is provided than, for example, angiography.

[0061] As used in the above summary and the following description, if an apparatus or method “companies” or “includes” (the two are interchangeable) certain features or steps, then such apparatus or method may also “consists essentially of” some of those features or steps, if identified in that way (i.e., the claims “consists essentially of”).

[0062] The technologies described herein include, in some embodiments, technologies for focusing intraluminal images by rotating a single-element ultrasonic transducer through image modification (e.g., angular diffraction, phase, amplitude, time shift, and synthesis of backscattered reflection images), including technologies described in U.S. Patent No. 63 / 497,962 (and a PCT application claiming priority thereto, filed April 11, 2024), technologies for manually assisted pullback for spatial alignment measurements, voice control, position sensors (e.g., encoders), including technologies described in U.S. Patent No. 63 / 531,266, titled "Systems and Methods for Intravascular Ultrasound Imaging," and technologies described in "Systems and Methods for Intravascular Ultrasound Imaging." This is used in conjunction with an ultrasonic imaging system and its components, voice control, and artificial intelligence algorithms, including the technology described in U.S. Patent No. 63 / 546,058, entitled "Ultrasound," all of which are incorporated in their entirety by reference in this disclosure.

[0063] The following drawings are for illustrative purposes only and illustrate non-limiting embodiments. In some embodiments, different features shown in the drawings can be combined. [Brief explanation of the drawing]

[0064] [Figure 1A] This is a block diagram of a rotating intravascular ultrasound system according to one embodiment.

[0065] [Figure 1B] This is a block diagram of a rotating intravascular ultrasound system equipped with a catheter interface module according to one embodiment.

[0066] [Figure 2A] This shows details of the distal tip of an imaging catheter having an elongated component including a rapid exchange (RX) lumen according to one embodiment.

[0067] [Figure 2B] This shows details of the distal tip of an imaging catheter having an elongated member including an over-the-wire (OTW) lumen according to one embodiment.

[0068] [Figure 3A] This is an isometric view of a connector hub of an IVUS catheter system according to one embodiment.

[0069] [Figure 3B] This is a side cutaway view of the connector hub shown in Figure 3A according to one embodiment.

[0070] [Figure 4] This is a lateral cross-section of the distal end of an elongated member including a lumen with a distal port according to one embodiment.

[0071] [Figure 5] This describes an exemplary process for filling a flashless intravascular ultrasound catheter according to one embodiment.

[0072] [Figure 6] Another exemplary process for filling a flashless intravascular ultrasound catheter according to one embodiment is shown.

[0073] [Figure 7] This describes an exemplary process for filling a flashless intravascular ultrasound catheter according to one embodiment.

[0074] [Figure 8] This shows an intravascular ultrasound system including a catheter according to one embodiment.

[0075] [Figure 9]This shows a subassembly of an intravascular ultrasound system including a catheter according to one embodiment.

[0076] [Figure 10] An imaging core according to one embodiment is shown.

[0077] [Figure 11] This shows the distal tip of a catheter according to one embodiment.

[0078] [Figure 12] A photographic diagram of one embodiment of the distal tip is shown.

[0079] [Figure 13] This shows an intravascular ultrasound system including a catheter according to one embodiment.

[0080] [Figure 14] This shows a subassembly of an intravascular ultrasound system including a catheter according to one embodiment.

[0081] [Figure 15] A catheter jacket according to one embodiment is shown.

[0082] [Figure 16] The distal tip portion according to one embodiment is shown.

[0083] [Figure 17] A cross-sectional view of a catheter jacket showing the guidewire lumen and imaging lumen according to one embodiment is shown.

[0084] [Figure 18] An intermediate shaft hub and proximal jacket according to one embodiment are shown.

[0085] [Figure 19] A proximal hub according to one embodiment is shown.

[0086] [Figure 20] This shows isometric views of the distal tip portion having an acoustic coupling medium according to various embodiments.

[0087] [Figure 21] This shows a proximal hub assembly process according to one embodiment.

[0088] [Figure 22] This shows a media filling process according to one embodiment.

[0089] [Figure 23A] An exploded view of a proximal hub assembly according to one embodiment is shown.

[0090] [Figure 23B] A cross-sectional view of a proximal hub assembly according to one embodiment is shown.

[0091] [Figure 24A] A cross-sectional view of a proximal hub having a strain relief component according to one embodiment is shown.

[0092] [Figure 24B] An isometric view of a proximal hub having a strain relief component according to one embodiment is shown.

[0093] [Figure 24C] An isometric view of a proximal hub having a strain relief component according to one embodiment is shown.

[0094] [Figure 25A] A cross-sectional view of the proximal hub and filling nozzle according to one embodiment is shown.

[0095] [Figure 25B] A cross-sectional view of a proximal hub and a filling nozzle engaged to fill the proximal hub with a binding medium is shown according to one embodiment.

[0096] [Figure 26A]This shows the media filling port of the proximal hub in the open position according to one embodiment.

[0097] [Figure 26B] This shows a media filling port of a proximal hub that engages with a filling nozzle according to one embodiment.

[0098] [Figure 26C] This shows the media filling port of the proximal hub when the proximal hub is disengaged from the filling nozzle, according to one embodiment.

[0099] [Figure 26D] This shows the media filling port of a proximal hub connector in a closed or sealed position according to one embodiment.

[0100] [Figure 27] An apparatus for degassing a binding medium according to one embodiment is shown.

[0101] [Figure 28A] An apparatus for heating a bonding medium according to one embodiment is shown.

[0102] [Figure 28B] This shows a syringe pump device for heating a binding medium according to one embodiment.

[0103] [Figure 29A] An isometric view of a catheter heating plate according to one embodiment is shown.

[0104] [Figure 29B] A side view of a catheter heating plate according to one embodiment is shown.

[0105] [Figure 30] A side view of the imaging core of an IVUS catheter according to one embodiment is shown.

[0106] [Figure 30A]Figure 30 shows a cross-sectional view of the proximal section of a transducer housing, illustrating an aperture according to one embodiment.

[0107] [Figure 31] This shows a side view of the proximal hub of an IVUS catheter according to one embodiment.

[0108] [Figure 32] A cross-sectional view of an IVUS catheter shaft according to one embodiment is shown.

[0109] [Figure 33] This shows the flow of an acoustically coupled medium through the imaging lumen of an IVUS catheter according to one embodiment.

[0110] [Figure 34] This is a process for degassing an acoustic coupling medium and filling an IVUS catheter, according to one embodiment. [Modes for carrying out the invention]

[0111] According to several embodiments, the systems and methods described herein relate to improved intravascular ultrasound imaging systems. According to several embodiments, the IVUS catheter includes a rotating imaging core within a sealed imaging lumen that contains an acoustic coupling medium, such as a fluid, configured to reduce or eliminate the need for the user to flush the imaging core before and during use. Various embodiments disclose methods for ensuring that the lumen of a flushless catheter is filled with a coupling medium that supports air-free imaging in the sealed coupling medium. In one embodiment, several methods for reducing or eliminating air bubbles within a sealed lumen are disclosed. Methods disclosed herein may include filling and sealing the lumen with a coupling medium to eliminate leakage and ensure that air bubbles do not interfere with the delivery of high-quality images.

[0112] Some embodiments described herein provide an IVUS catheter having a proximal connector hub assembly that facilitates the process of filling the IVUS catheter imaging lumen with an acoustic coupling medium during the catheter manufacturing process. The coupling medium can encapsulate an imaging transducer, thereby forming an imaging path that is not obstructed by air bubbles.

[0113] In some embodiments, the proximal connector hub assembly may include a proximal connector hub having a filling port, a filling port cap, and a filling port cover, according to some embodiments. The filling port may receive a filling port cap, which may include an elastomer seal component or a rigid plastic cap. The filling port cap may be mated with a filling adapter of a filling nozzle, which can be used to fill the imaging lumen of an IVUS catheter with an acoustic coupling medium. In one embodiment, if the filling port cap is an elastomer seal, the filling nozzle may include a needle for puncturing the seal and filling the catheter. Once the IVUS catheter is filled, the filling nozzle and filling port adapter may be disengaged from the filling port cap and subsequently covered by the filling port cover. Once the IVUS catheter is filled, the filling nozzle and filling port adapter can be disengaged from the filling port cap, thereby drawing the acoustic coupling medium into the filling port cap and preventing air from entering the imaging lumen of the IVUS catheter. In some embodiments, the proximal connector hub assembly may include a proximal connector hub having a filling port, a filling port valve cap, and a filling port cover, according to some embodiments. The filling port may receive a filling port valve cap. The filling port valve cap can be fitted with a filling adapter for a filling nozzle that can be used to fill the IVUS catheter with an acoustic coupling medium. Once the IVUS catheter is filled, the filling nozzle and filling port adapter can be disengaged from the filling port valve cap, thereby drawing the acoustic coupling medium into the filling port valve cap and preventing air from entering the imaging lumen of the IVUS catheter.

[0114] In some embodiments, the proximal connector hub may include strain relief components that can reduce or prevent bending and excessive local strain within the IVUS catheter. According to some embodiments, the proximal hub connector may also include a seal, a drive bushing, a drive hub, a drive hub pin, and / or an electronic identification (EID) printed circuit board (PCB). The drive bushing may reduce wobble and / or uneven rotational strain (NURD) and prevent acoustic coupling fluid leakage by maintaining uniform friction around the inner diameter of the seal.

[0115] Several methods described herein can provide degassing of acoustic coupling media and filling of IVUS catheters with degassed acoustic coupling media. Pre-filling the catheters with acoustic coupling media during manufacturing can optionally and advantageously eliminate the need for the user to prepare the lumen around the internal imaging core and flush it with fluid. In some embodiments, degassing the acoustic coupling media has the advantage of reducing the level of dissolved air in the medium, so that any small amount of air remaining in or introduced into the catheter during the manufacturing process or the storage life of the device is dissolved or absorbed into the medium. Furthermore, some embodiments of the methods described herein advantageously prevent the introduction of air into the acoustic coupling media during filling, which improves the quality of images captured by the IVUS catheter and reduces procedure time by eliminating the need to replenish or replace the IVUS catheter, among other advantages described herein.

[0116] In some embodiments, the degassing process includes exposing an acoustically coupled medium to a vacuum (or low) pressure for a period of time. In one embodiment, the degassing process can be initiated by providing a degassing device. The degassing device may include a container, a vacuum pump, a magnetic stirring hot plate, and a syringe. The container may be connected to the vacuum pump via a tubing section and a first valve, such as a directional valve. The container may be connected to the syringe via a second valve, such as a stopcock valve. The acoustically coupled medium may be placed in the container for a first period of time. The first period may be a set period or may continue until the acoustically coupled medium reaches an air saturation threshold. After the first period, the acoustically coupled medium may be exposed to vacuum pressure for a second period of time. The second period may be a set period, as described later, or may continue until the acoustically coupled medium reaches a desaturation threshold. Once the acoustically coupled medium reaches the desaturation threshold, the medium may be transferred to the syringe (e.g., via a tubing section and a second valve). In one embodiment, the magnetic stirring plate is a hot plate, and the degassing process also includes heating the acoustic coupling medium to reduce the viscosity of the fluid and facilitate the subsequent filling process.

[0117] According to some embodiments, the technologies described herein, including, for example, IVUS flashless technology, include a reversible flash port seal that allows for product modification after inspection (e.g., checking for remaining bubbles or image quality) and optionally before permanent sealing. In some embodiments, the filling and / or flashing procedure can be repeated using the reversible port seal until satisfactory results are obtained (e.g., removal of bubbles). In one embodiment, the seal is reversible. In one embodiment, the seal is permanent. In some embodiments, the filling port may be temporarily sealed to facilitate inspection and permanently sealed once the successful filling process is confirmed. In some embodiments, the temporary seal of the filling port can be removed to facilitate further fluid filling process steps.

[0118] The IVUS catheter may be filled with a degassed acoustically coupled medium. In some embodiments, the filling process can be initiated by providing an IVUS catheter filling device and pressurizing the medium with a syringe pump device or other fluid pump device. The filling device may also include means for heating the catheter, for example, on a heating plate, and / or a microscope for monitoring the filling process and inspecting for bubbles during the filling process. The IVUS catheter may be placed in the catheter heating plate and heated to a target catheter temperature. The catheter heating plate may include a notch for receiving the IVUS catheter. The notch may be S-shaped, spiral, or a straight path, and may be molded based on one or more characteristics of the IVUS catheter.

[0119] A syringe pump device can accept a syringe filled with degassed acoustically coupled medium. The syringe pump device may include a syringe pump, a syringe heating component (e.g., a syringe jacket), a pressure gauge, at least one tubing section, a pump, and / or a three-way valve. The syringe pump can accept the syringe, and the syringe heating component is positioned around the syringe to heat the syringe to a target temperature, e.g., 60°C. The syringe pump can discharge the acoustically coupled medium from the syringe through the pressure gauge into the tubing section. In some embodiments, the syringe pump can discharge the acoustically coupled medium at a target delivery rate, e.g., 0.4 mL / min. The delivery rate can be modified based on whether the pressure in the syringe pump device or IVUS catheter exceeds a pressure threshold, e.g., 80 psi. In some embodiments, the syringe pump can discharge the acoustically coupled medium at a target filling pressure.

[0120] The acoustic coupling medium can pass through the tubing via a valve, such as a three-way valve, to the pump. The pump can be connected directly or via a filling nozzle and / or filling adapter to the filling port of the proximal connector hub of the IVUS catheter. The pump can fill the catheter imaging lumen by pushing the acoustic coupling medium from the tubing and / or syringe into the proximal connector hub of the IVUS catheter. The pump can also, according to some embodiments, push air out of the imaging lumen of the IVUS catheter.

[0121] In some embodiments, the filling process may include rotating the imaging core while the medium fills the imaging lumen to facilitate the removal of air from inside and around the imaging core. In various embodiments, the rotation speed is 500 to 2000 rpm (e.g., 500, 600, 700, 800, 900, 1000, 1200, 1400, 1600, 1800, 2000 rpm, + / - 100 rpm, and overlapping ranges and values ​​therein). The target speed may be configured to minimize residual air in the system during filling. In one embodiment, for example, if bubbles adhere to the inner wall of the imaging lumen at a speed faster than necessary to help them move distally, the target speed may be temporarily reduced and then increased again to shorten the overall filling time.

[0122] Some embodiments described herein provide an IVUS catheter having one or more features that allow the catheter to be more easily filled with an acoustically coupled medium while minimizing the risk of air being introduced into the medium. The IVUS catheter may include an imaging core located within the imaging lumen of the catheter. The imaging core may include a cable-connected transducer located within a transducer housing attached to the distal end of a torque coil according to one embodiment. The proximal end of the torque coil may optionally be attached to a drive shaft in a proximal connector hub. A coaxial cable may be placed inside the torque coil to connect the transducer to a printed circuit board in the proximal connector hub. The coupling component may connect the transducer housing to the coil. The transducer, transducer housing, and / or coupling may include one or more apertures according to some embodiments. The drive shaft may also include one or more apertures according to some embodiments. The IVUS catheter may include a first gap in the lumen between the coaxial cable and the torque coil, and a second gap between the torque coil and the inner diameter of the imaging lumen.

[0123] Advantageously, in some embodiments, the difference in cross-sectional area of ​​one or more apertures and / or first and second gaps arranged throughout the IVUS catheter reduces resistance to the flow of media for removing air inside the coil within the IVUS catheter, improving the speed and efficiency at which the IVUS catheter can be filled and making air bubble removal more effective. This can improve the overall quality of the IVUS images captured by the IVUS catheter.

[0124] In some embodiments, image clarity is important for the proper identification of lesions, plaques (e.g., hard plaques, soft plaques, fragile plaques, calcified plaques, substantially non-calcified plaques, fibrous fatty plaques), thrombi, calcium accumulations, dissections, and the measurement of these abnormalities. IVUS imaging can be useful for planning and guiding treatment choices in interventional cardiology, vascular surgery, and interventional radiology throughout the body, from the heart to the peripheral vascular system, for example, for measuring lesions and guiding and evaluating stent placement. In some embodiments, IVUS catheters are used on arteries, veins, and blood vessels (e.g., carotid arteries, subclavian vessels, pulmonary vessels, aorta, renal vessels, iliac vessels, arteriovenous (AV) fistulas, femoral vessels, popliteal vessels, tibial vessels, etc.). In some embodiments, intraluminal imaging is achieved using the apparatus and methods described herein. Imaging and diagnosis of intraluminal (e.g., intravascular, lumen, gastrointestinal tract, esophagus, stomach, intestine, rectum, pancreas, sinuses, ureter, bladder, gynecological, etc.) tissues can help identify irregularities, diseases, and / or injuries for medical treatment to improve patient outcomes. For example, endoscopes may be used in conjunction with some of the features described herein. Transvaginal and other gynecological ultrasound devices may also include some of the features described herein. In embodiments where EUS (endoscopic ultrasound) and other intraluminal imaging or imaging of other body cavities or organs is performed (and such imaging is not intravascular), the features described herein for “IVUS” or “catheter” should be understood to apply to intraluminal (or other cavity / organ) catheters, probes, tubing, scopes, and other such devices. The technologies described herein are used in some embodiments in conjunction with other medical imaging systems (such as cardiac catheterization systems) to provide physicians, such as cardiologists, with a more sophisticated healthcare portfolio. In some embodiments, the collaborative platform improves the workflow between IVUS and one or more other imaging systems (e.g., X-ray systems). In one embodiment, stent placement and other procedures are optimized using the IVUS techniques described herein, along with X-ray, external ultrasound, and / or other non-IVUS techniques.

[0125] Imaging and diagnosis of intravascular or extravascular tissue are achieved herein in several embodiments, including the identification of irregularities. The term “irregularity” as used herein may be given its ordinary meaning and shall also include vascular or other malformations, stenosis, occlusion, dilation, disease, and injury. Irregularities may also include lesions, thrombi, aneurysms, dissections, plaques (e.g., hard plaques, soft plaques, fragile plaques, calcified plaques, substantially non-calcified plaques, fibrous fatty plaques), thrombi, fistulas, tumors, neoplasms, gallstones, kidney stones, polyps, cysts, etc., and the measurement of morphological evaluations of such irregularities within vascular, other body lumens, or other target sites. In some embodiments, irregularities may also include incomplete stent or balloon adhesion, dissociation (e.g., after atherosclerosis, balloon angiogenesis, etc.), identification of the etiology of compression, insufficient expansion of stents or other devices, and IVUS-guided sizing and grading of the severity of irregularities or insufficient expansion of stents, such as iliac vein stents. Irregularities of the esophagus, stomach, and small intestine can be visualized using some of the embodiments described herein (e.g., via endoscopic ultrasound imaging).

[0126] In addition to identifying irregularities, some embodiments of this specification are used to facilitate the relevant measurements and preparations for deploying stents and / or balloons, and are useful for healthcare professionals in planning treatment.

[0127] After identifying the irregularity, appropriate treatment can be applied to the patient. For example, image-guided therapies can be used for tumors, thrombi, plaques, etc., and imaging and treatment capabilities reside in a single device or multiple devices. Some embodiments include, for example, percutaneous coronary intervention for coronary artery lesions, intravascular image-guided percutaneous intervention for peripheral vascular lesions, and / or intravascular image-guided percutaneous intervention in arteries and / or veins. In some embodiments, the IVUS system is configured for optimized peripheral vascular procedures. In some embodiments, the IVUS system is configured for optimized peripheral vascular procedures and not for coronary artery procedures. In some embodiments, the IVUS system is configured for coronary artery procedures. In some embodiments, the IVUS system is configured for neurovascular procedures (including, but not limited to, cerebral vascular procedures). In some embodiments, the IVUS system is configured for intravascular ultrasound-guided thrombectomy, including, but not limited to, mechanical thrombectomy. In some embodiments, the IVUS system is configured for ultrasound-guided pulmonary embolization. In some embodiments, simultaneous real-time IVUS guidance is provided for procedures such as thrombectomy / embolization, stent placement, blood clot aspiration, and other coronary or neurovascular procedures.

[0128] While some embodiments described herein describe IVUS, the techniques described herein can also be used for intraluminal imaging (non-intravascular). For example, some embodiments are used to provide imaging, diagnosis, and / or image-guided interventions for the gastrointestinal tract, esophagus, stomach, intestines, rectum, sinuses, ureters, bladder, uterus, fallopian tubes, lungs, brain, etc. The systems and methods described herein can be used in combination with an endoscope rather than an IVUS catheter to support the identification and diagnosis of gastrointestinal tumors, such as tumors of the intestines and / or bile ducts. Similarly, the systems and methods described herein can be used to image the sinuses using IVUS.

[0129] Figures 1A and 1B show an intravascular ultrasound (IVUS) system 100 according to one embodiment. In various embodiments, the system 100 is flashless. In various embodiments, the system 100 includes reusable and / or disposable components. In one embodiment, the disposable component is one or more of a family of imaging catheters 101, such as one or more peripheral imaging catheters. The imaging catheter 101 may include a catheter body 102, a catheter shaft 110, an imaging core 104, a transducer 105, and a proximal connector hub 116. In one embodiment, the imaging catheter 101 may include a proximal connector that can be attached to the interface to the catheter body 102, catheter shaft 110, imaging core 104, transducer 105, and proximal connector hub 116. In one embodiment, such as the embodiment shown in Figure 1A, the reusable component is a console 118, and the catheter body 102 is directly attached to the console by the proximal connector hub 116, etc. The console 118 may include one or more processors 112, one or more transceivers 113, and / or actuators 114. In one embodiment, such as the embodiment shown in Figure 1B, the reusable components of the system 100 may include a catheter interface module (CIM) 115 that can be positioned between the console 118 and the catheter 101. The transceivers 113 and actuators 114 may be part of the CIM 115, and the CIM may be separate from the console 118 or attached to the console via a cable. According to some embodiments, some of the transceivers 113 and actuators 114 may be distributed between the console 118 and the CIM 115. The CIM 115 may be positioned to communicate electronically with the console 118. For example, the CIM 115 may be connected to the console 118 using a cable, and the proximal connector hub 116 of the catheter 101 may be connected to the CIM 115. The intravascular ultrasound system 100 may include a catheter 101 having a catheter body 102, a console 118, and a display 120.The display 120 may be part of the console 118. The catheter body 102 of the catheter 101 may be a flexible, elongated member. The catheter body 102 may be divided into a working length portion that can be inserted into the patient and a proximal extension portion that connects the working length to the proximal connector hub 116. The working length portion may be a fixed length that allows the distal catheter imaging portion to be positioned from the vascular access site to the treatment site. In some embodiments, the catheter 101 has a proximal extension portion configured to attach the proximal connector 116 to a catheter interface module 115 outside the sterile field. In various embodiments, the working length of the catheter body 102 may be at least 90 cm, at least 120 cm, at least 150 cm, at least 180 cm, at least 210 cm, at least 240 cm, at least 270 cm, at least 300 cm, at least 330 cm, or at least 360 cm (for example, lengths of 90, 100, 110, 125, 150, 175, 200, 230, 250, 280, 310, 350, 370, or 400 cm, including values ​​within that range). In various embodiments, the catheter body 102, including both the working length and the proximal extension portion, may be at least 3 feet (ft), at least 4 ft, at least 5 ft, at least 6 ft, at least 7 ft, at least 8 ft, at least 9 ft, at least 10 ft, at least 11 ft, at least 12 ft, or at least 13 ft. In some embodiments, the catheter body 102 may be of a fixed length and may not include any extension portion. In some embodiments, one or more radiopaque (RO) markers are spaced apart along a portion of the length of the catheter body 102. The catheter body 102 may consist of one, two or more housings, lumens, coils, media, connectors, sensors, and / or measuring devices. In various embodiments, the catheter body 102 includes an imaging lumen 108 containing an imaging core 104. The annular space between the imaging lumen 108 and the imaging core 104 having a distal transducer 105 may be filled with an acoustic coupling medium 109.In some embodiments, the catheter body 102 may include one, two, or more material layers to refract the ultrasonic signal and / or limit the backscatter signal in the intended manner. The catheter body 102 may have one, two, or more connecting elements, such as parts of various materials and flexibility. The catheter body 102 has a proximal end and a distal end. The distal end may include a distal tip. In some embodiments, the catheter body 102 includes a guidewire lumen to allow the catheter to advance on the guidewire to a target site. In one embodiment, as shown in Figure 2A, the guidewire lumen extends over the length of the distal tip in a rapid-replace (RX) tip design, and the guidewire exit port is located at the proximal end of the distal tip. In some embodiments, the distal tip includes a distal plug, as will be described in more detail in relation to Figure 4. In another embodiment, the guidewire lumen extends over the working length of the catheter body 102, as shown in Figure 2B.

[0130] The imaging core 104 includes, in some embodiments, a drive shaft and a distal transducer 105. The transducer 105 may be a single-element transducer or a multi-element array of transducers in various embodiments. In one embodiment, a single ultrasound transducer (e.g., only a single element, no multiple elements, no more than two elements, and / or no array of elements) is positioned internally within the vascular space within the catheter for acoustic imaging. In various embodiments, the multi-element array may be a 2, 8, 10, 12, 16, 24, 32, 50, 64, 100, or 128-element array. In one embodiment, the transducer is rotated by an actuator, while one, two, or more receiving transducers may remain stationary. The catheter body 102 optionally has a flexible wall extending along the length of the catheter from the proximal end to the distal end. The catheter body 102 may also include one or more lumens, such as an imaging lumen 108. In some embodiments, the catheter body 102 may include two or more lumens, such as a guidewire lumen and an imaging lumen. In one embodiment, the imaging lumen 108 may extend from the proximal end to the distal tip of the catheter body 102 and terminate before the distal end of the tip. In one embodiment, the imaging lumen 108 may extend from the proximal end to the distal portion of the catheter body 102. The imaging lumen 108 may be defined by the wall of the catheter body 102. In one embodiment, the wall of the catheter body is flexible. According to some embodiments, the imaging lumen 108 may be defined by the wall of a member inserted into the catheter body 102. In some embodiments, the catheter body 102 may include two or more lumens. The imaging lumen 108 may be sealable and may have a proximal opening and a distal opening. The imaging lumen 108 is sealable and may have a proximal port and a distal port. The proximal opening of the imaging lumen may be connected to a filling port, for example, a filling port in a proximal connector 116. The distal opening may be located at or near the distal end of the imaging tube lumen 108 and may include a small opening that allows air to be expelled during the filling process and is then sealed.The proximal and distal openings may be sealed as described below in relation to Figures 3A-3B, 4, and 5. The imaging lumen 108 is sealable and may have a proximal and distal port. The proximal port may be located at or near the proximal end of the imaging lumen 108, and the distal port may be located at or near the distal end of the imaging lumen 108. The proximal and distal ports may be sealed as described below in relation to Figures 3A-3B, 4, and 5. In various embodiments, the lumen may be an internal lumen (e.g., an imaging lumen). In various embodiments, the wall may be an inner wall or an outer wall. In various embodiments, the transducer may be an internal transducer. In various embodiments, the imaging core 104 may be an internal imaging core 104.

[0131] In some embodiments, the imaging catheter 101 of system 100 includes a catheter body 102, an imaging core 104 having a rotary transducer 105 positioned inside the imaging lumen 108, and a proximal connector hub 116. In various embodiments, the rotary transducer 105 is a component of the imaging core 104. The rotary transducer 105 is positioned in the distal portion of the imaging lumen 108 of the catheter body 102 and can generate multiple ultrasonic signals 106. In some embodiments, the rotary transducer 105 may be oriented so that the ultrasonic signals propagate perpendicularly to the catheter body 102. In some embodiments, the rotary transducer 105 may be oriented so that the ultrasonic signals propagate in a circular shape perpendicular to the catheter body 102. In some embodiments, the ultrasonic signals propagate away from perpendicular to the catheter body wall, forming a cone shape relative to the catheter wall. The rotary transducer 105 may be oriented so that the ultrasonic signals propagate perpendicular to the axis. In various embodiments, a device such as a catheter 101 may include an imaging core 104 with a rotating ultrasonic transducer 105 connected to the distal end of a drive shaft 110. The catheter body 102 of the catheter 101 may include a flexible elongated member having a sealed imaging lumen 108, the sealed lumen configured to receive the ultrasonic imaging core 104 and an acoustic coupling medium 109, the sealed lumen including a proximal end, a distal end, and a flexible wall extending to a length between the proximal and distal ends, the proximal end connected to a filling port of a proximal connector 116, and the distal end including a distal seal such as a distal plug.The device may include a rigid connector hub comprising an internal chamber, a medium-filling port, a distal interface, a proximal interface, and a flexible seal. The medium-filling port is configured to insert an acoustically coupled medium into the rigid connector hub to fill a sealed lumen; the distal interface is configured to connect to the proximal end of the catheter body 102; the proximal interface is configured to connect to a console, which is configured for rotational operation of the drive shaft; the flexible seal is distally connected to a seal housing connected to the proximal interface; the flexible seal is proximal connected to the chamber of the rigid connector hub; the drive shaft extends distally through the flexible seal; and the sealed lumen communicates with the flexible seal, chamber, and distal plug of the catheter body 102 via the sealed medium. Strain relief is positioned above the proximal end of the catheter body 102 and the distal interface of the proximal connector hub 116 to prevent bending or excessive bending where the flexible catheter body is attached to the rigid proximal connector hub 116. The rotating transducer 105 can also detect multiple backscatter signals. In some embodiments, the catheter 101 of system 100 may include one, two, or more generating transducers and one, two, or more receiving transducers.

[0132] In one embodiment, the imaging lumen 108 is configured to receive an imaging core 104 comprising a rotary transducer 105 and a drive shaft 110. The drive shaft 110 optionally mechanically couples the rotary transducer 105 to a component in a proximal hub 116, which is connected to an actuator 114 when the catheter is connected to a CIM 115 or console 118. The imaging lumen 108 may also be configured to receive a binding medium 109. In various embodiments, the binding medium is biocompatible, sterilizable, and / or acoustically compatible. For example, the binding medium may be polyethylene glycol (PEG), PEG with some water, water, saline, glycerin, and / or oil (e.g., natural, mineral, etc.), or a combination thereof. In various embodiments, the binding medium does not contain PEG, water, saline, glycerin, or oil. In various embodiments, the binding medium is degassed before insertion into the imaging lumen 108. In one embodiment, the binding medium has a higher viscosity than water, reducing or eliminating non-uniform rotational strain (NURD). In various embodiments, the acoustic binding medium may include a colorant to facilitate visual monitoring of the filling process during the manufacture of the catheter 101 in order to confirm the elimination or reduction of potential bubbles (e.g., a reduction of 5%, 10%, 20%, 25%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, or 100%).

[0133] In various embodiments, the proximal connector hub 116 of the imaging catheter 101 of system 100 is configured to connect to an actuator 114. The actuator 114 may include components or connections configured to couple catheter components, such as a drive shaft, to a motor in the console or CIM, thereby causing relative motion between two or more components (e.g., motion between a rotary transducer 105 and the catheter body 102) (e.g., rotational motion and / or translational motion, rotational motion without translational motion, and / or translational motion without rotation). The actuator 114 may include one, two, more, or a combination thereof, such as hubs, seals, valves, adhesives, bearings, hinges, pins, ball and pinion, axles, rotary joints, clutches, discs, gears, belts, motors, linear slides, linear actuators, tracks, grooves, slots, cams, vibratory tables, etc. The proximal connector hub 116 may include a mechanism that connects to the actuator 114 such that the rotation of the actuator 114 transmits torque force to the drive hub 2316, thereby causing the drive hub 2316 to rotate, thereby driving the drive shaft 110 of the imaging core 104. In some embodiments, the actuator does not necessarily need to be connected to an electronic system, an electric system, or other automatic system, and embodiments of the actuator described herein can be configured to move manually, semi-automatically, and / or automatically. For example, the actuator 114 may be a drive system or a drive shaft. The actuator 114 can rotate the rotary transducer 105 in the catheter body 102 in the azimuthal direction.

[0134] In one embodiment, the catheter 101 can be connected to one, two, or more processors 112 in a console or CIM via a connector hub 116, 300, which is shown in detail in Figures 3A and 3B. The connector hub 116 may include rigid and / or flexible elements. For example, according to some embodiments, the connector hub 116 may include one, two, or more seals surrounding an acoustic coupling medium in the imaging lumen 108. The connector hub 116 may also include a medium-filling port for inserting the acoustic coupling medium into the imaging lumen 108. In some embodiments, the connector hub 116 may include mechanical and electrical connections to actuators 114 and processors 112, which can be housed in the console 118 or CIM 115. According to alternative embodiments, one, two, or more processors may be present.

[0135] In some embodiments, the connector hub 116 can also provide proximal rotation of the imaging core 104. In one embodiment, a keyed mechanical connection from the connector hub 116 to the console 118 or CIM 115 provides a tight connection to rotational force efficiently transmitted from the rotary motor actuator 114 to the drive shaft 110 of the imaging core 104 within the catheter 101. In some embodiments, the connector hub 116 can maximize torque control of the coil of the drive shaft 110 within the catheter body 102. In some embodiments, the connector hub 116 can connect the catheter body 102 to a console 118 which includes a processor 112 and other components. For example, the console 118 may include an actuator 114, an intravascular ultrasound transceiver 113 (for transmitting and receiving ultrasound acoustic pulses), an upgradeable catheter-specific electrical matching network, and / or a microphone for providing an audio control interface. In some embodiments, the actuator and ultrasound transceiver may be located in a CIM which can be connected to the console via cables. In some embodiments, the console 118 may include a user interface and / or display, including a wireless medical-grade tablet that can be docked and charged between procedures. The tablet may include one or more microphones for providing a voice control interface.

[0136] During treatment, the distal end of the catheter 101 can be inserted into the patient. The processor 112 can control various elements of the system 100 to generate ultrasound images, which can be provided to the display device 120. During treatment, the distal end of the catheter 101 can be inserted into the patient's blood vessel. The processor 112 can control various elements of the system 100 to generate ultrasound images of the blood vessel wall, blood flow, and surrounding tissue, which can be provided to the display device 120. In some embodiments, the processor 112 can control the rotation of the rotary transducer 105 at the distal end of the actuator 114 and the imaging core 104 of the catheter 101. In some embodiments, the actuator 114 can rotate the rotary transducer 105 at a fixed speed. In some embodiments, the actuator 114 can rotate the rotary transducer 105 at one or more variable speeds.

[0137] The processor 112 can instruct the rotary transducer 105 to generate an ultrasonic signal and to detect a backscatter signal generated by the blood and tissue surrounding the catheter 101 in response to the ultrasonic signal. In some embodiments, the processor 112 can cause the rotary transducer 105 to cycle between generating an ultrasonic signal and detecting a backscatter signal. For example, the processor 112 can generate an electrical pulse that causes the rotary transducer to emit an ultrasonic signal 106. Multiple ultrasonic signals may include ultrasonic signals having different frequencies and / or amplitudes. In various embodiments, the imaging device, such as an IVUS catheter, has an imaging frequency (for example, in the range of 1 to 90 MHz (e.g., 1 to 10, 10 to 15, 10 to 20, 10 to 25, 10 to 30, 10 to 40, 15 to 35, 20 to 30, 30 to 40, 40 to 50, 20 to 25, 20 to 30, 20 to 40, 20 to 45, 20 to 50, 25 to 35, 25 to 40, 25 to 45, 25 to 50, 30 to 45, 30 to 50, 40 to 45, 45 to 50 MHz and any value and range within that range)). The rotating transducer 105 responds to the ultrasonic signal 106 by posterior dispersion generated by the blood and / or tissue surrounding the catheter body. Disruptive signals can be detected. The processor 112 can receive backscatter signals from the rotary transducer 105 and generate an ultrasonic image. In some embodiments, the processor 112 can process the backscatter signals by filtering, beamforming, adjusting, and / or transforming them. The processor 112 can provide an ultrasonic image to be displayed on the display device 120. The display device 120 may be any device suitable for providing a visual output, including televisions, monitors, mobile devices, tablets, smartwatches, projector screens, etc.

[0138] The processor 112 can run an imaging software platform. The imaging software platform can provide a user interface for controlling the system 100. In some embodiments, the processor 112 can generate the user interface on the display device 120. The imaging software platform can provide multiple client interfaces and image data platforms. In some embodiments, the imaging software may allow the user to manually draw the boundaries of an ultrasound image. For example, a physician during a procedure can draw a boundary around a blood vessel shown on a touch-input display such as a medical-grade tablet. In response, the system 100 can provide updated images only within the boundary. The imaging software can provide 3D visualization techniques and / or pullback summaries.

[0139] In some embodiments, the distal end of the catheter 101 accommodates an imaging transducer 105. Figure 2A shows the distal end of an elongated member 200 of the catheter 101, including an imaging lumen 202 and a rapid-replacement (RX) guidewire lumen 204, according to one embodiment. In some embodiments, the elongated member 200 includes one or more housing layers 206. In some embodiments, the RX lumen 204 is located at the distal tip, including a distal plug 406 as shown in Figure 4. The imaging lumen 202 of the elongated member 200 can accommodate a rotary transducer 208 mechanically connected to a drive shaft 210. The lumen 202 may also accommodate an acoustic coupling medium. The coupling medium may be a liquid or a gel. For example, the coupling medium may be polyethylene glycol (PEG), PEG with some water, water, saline solution, glycerin, natural oil, or a combination thereof. In various embodiments, the coupling medium has a density and velocity of acoustic values ​​similar to those of the catheter jacket material to prevent or reduce undesirable reflections from the medium / jacket interface and to prevent or reduce refraction of the acoustic beam. In some embodiments, the acoustic coupling medium has a velocity of sound value configured for improved lateral imaging performance. In some embodiments, the acoustic coupling medium has a velocity of sound value configured for improved lateral performance. In one embodiment, the geometric shape of a rotating element catheter can include a focusing lens for ultrasound, made up of a gently convex circular layer of material on the transducer surface having a velocity of sound slightly lower than that of the material being imaged. In one embodiment, a tightly curved shell (catheter body) and inner material (coupling medium) with a high velocity can be selected to be close to, and possibly even higher than, that of the material being imaged. In one embodiment, the geometric design of a rotating catheter having a thin, relatively high-velocity catheter body and a coupling medium inside it can be configured to have a considerably advantageous focusing effect. This embodiment can be configured to be unexpected and surprising, as the focusing lens for ultrasound is made up of a gently convex circular layer of material on the transducer surface having a velocity of sound slightly lower than that of the material being imaged.In one embodiment, the high-velocity, tightly curved shell (catheter body) and inner material (binding medium) can be selected to be close to or even higher in velocity than the material being imaged. PEG can be supplied in a range of 5–90% (e.g., 5–10%, 10–25%, 20–50%, 40–80%, and overlapping ranges therein). PEG can be supplied in various low molecular weight grades of polyethylene glycol. PEG can be supplied in various medium molecular weight grades of polyethylene glycol. PEG can be supplied in various high molecular weight grades of polyethylene glycol.

[0140] Figure 2B shows the distal end of an elongated member 212 of a catheter 101 including a plurality of lumens 214, 218 according to one embodiment. In some embodiments, one of the lumens 218 may be an over-the-wire (OTW) guidewire lumen. In some embodiments, the catheter may include a guidewire lumen 218. The elongated member 212 may include a distal tip 216. According to some embodiments, the elongated member 212 may include a second guidewire lumen 218. The imaging lumen 214 can receive a rotary transducer 208 mechanically connected to the drive shaft 210. The imaging lumen 214 may also receive an acoustic coupling medium. The guidewire lumen 218 can receive a guidewire, and the guidewire lumen 218 extends to the end of the distal tip 216. In one embodiment, the guidewire lumen 218 does not include an acoustic coupling medium. In one embodiment, the lumen space surrounding the transducer 208 includes an acoustic coupling medium sealed inside the imaging lumen 214.

[0141] Figure 3A is an isometric view of the proximal connector hub 300 of one embodiment of the IVUS catheter 101, and Figure 3B is a cross-sectional view thereof. In one embodiment, the connector hub 300 is a rigid material having one or more flexible seals 304 as shown in Figure 3B, supporting the sealed medium while allowing the imaging core 104 and drive shaft 210 to operate via rotation and / or linear motion along the catheter axis without leakage of the medium, and preventing air from entering the catheter lumen using one or more seals and / or valves. In one embodiment, the flexible seal 304 surrounds the drive shaft 210 (extending distally through the flexible seal and through the connector hub into the lumen of the catheter body 102) inside the rigid connector hub that holds the medium in the lumen while the imaging core 104 rotates. In one embodiment, the flexible seal 304 is a circular (e.g., O-ring) seal that is compressed with sufficient force on the imaging core 104 of the connector hub 300 to prevent leakage, while a motor or actuator in the imaging console can still rotate the imaging core 104 at a speed that supports a high imaging frame rate. In various embodiments, the flexible seal 304 is made of nitrile, nitrile rubber, nitrile butadiene rubber, Buner N, acrylonitrile butadiene rubber, ethylene propylene rubber, ethylene propylene diene monomer rubber, fluorocarbon, fluoroelastomer, fluororubber, synthetic rubber polymer (such as Viton), silicone rubber, acrylonitrile-derived rubber, and similar materials. The connector hub 300 can be connected to the proximal connector strain relief 302 of the IVUS catheter 101. In some embodiments, the drive hub component of the connector hub 300 is connected to the drive shaft of the imaging core 104. In one embodiment, the connector hub 300 is integrated with the catheter body such that the connector hub 300 forms the proximal end of the catheter body. In one embodiment, the connector hub 300 is separate from the catheter body, such that the connector hub 300 is adjacent to or near the proximal end of the catheter body.

[0142] Figure 3B is a side cutaway view of the connector hub 300 shown in the embodiment of Figure 3A. In one embodiment, the housing portion of the connector hub 300 is rigid. In one embodiment, the connector hub 300 includes an internal chamber 305. In one embodiment, the connector hub 300 includes an internal chamber 305 that communicates with a distal interface 303, a proximal interface 308, and / or a medium-filling port 312 via a medium.

[0143] In one embodiment, the connector hub 300 includes a distal interface 303 configured to connect to the proximal end of the catheter body 102. In one embodiment, the drive shaft 210 extends through the distal interface 303 (the portion shown in Figure 3B).

[0144] In one embodiment, the connector hub 300 includes a proximal interface 308 configured to connect to a connector to a console. In various embodiments, the connector mechanically and / or electrically connected to the console includes a flexible seal. In one embodiment, the drive shaft 210 extends through the connector and is securely attached to the drive hub in the proximal interface 308. The drive hub interfaces with an actuator 114 when the catheter 101 is connected to the CIM 115 or console 118, and the rotation of the actuator 114 rotates the drive hub, which in turn rotates the drive shaft and the imaging core.

[0145] In one embodiment, the connector hub 300 includes one or more seal ports 310. The proximal interface 308 may also include one or more seal ports 310. The proximal interface 308 may be adjacent to, connected to, or otherwise coupled to the seal ports 310. In some embodiments, the seal ports 310 may be apertures of the body of the connector hub 300 and may be located radially above the seal housing 306. The seal ports 310 can provide access to the seal housing 306 and the flexible seal 304. In some embodiments, the seal ports 310 may enable the connector hub 300 to be attached to, joined, and / or bonded to one or more seal housings 306. For example, adhesive can be applied to the seal housing 306 and the flexible seal 304 via the seal ports 310. In some embodiments, one, two, three or more seal ports 310, the flexible seal 304, and the seal housing 306 are used.

[0146] In one embodiment, the connector hub 300 includes a medium filling port 312. The medium filling port 312 is configured to connect to a source or reservoir of acoustically coupled medium 109. The medium filling port 312 can be configured to insert the acoustically coupled medium into the imaging lumen of the elongated member of the IVUS catheter through the connector hub 300. The medium filling port 312 may be sealed after the imaging lumen has been filled with medium. The medium filling port 312 may be molded to accommodate different connector shapes. The medium filling port 312 may be located proximal to the distal interface 303 and distal to the flexible seal 304 and the proximal interface 308. The position of the medium filling port 312 can help remove all air bubbles during the filling process. In some embodiments, the medium filling port 312 can be sealed with adhesive and / or plugs, as described below in relation to Figure 4. In one embodiment, the filling port 312 has its most proximal inlet juxtaposed with the flexible seal 304 to help remove all air bubbles during the filling process. The hub may also include a filling port cap and a filling port cover, according to some embodiments. The filling port may receive a filling port cap, which may be either an elastomer seal component or a rigid plastic cap. The filling port cap may be fitted with a filling adapter of a filling nozzle, which can be used to fill the IVUS catheter with an acoustic coupling medium. Alternatively, if the filling port cap is an elastomer seal, the filling nozzle may include a needle for puncturing the seal and filling the catheter. Once the IVUS catheter is filled, the filling nozzle and filling port adapter may be disengaged from the filling port cap and covered by the filling port cover.

[0147] In various embodiments, the connector hub 300 includes one or more flexible seals 304. The flexible seals 304 surround the drive shaft 210 within the connector hub 300 and can seal the bonding medium in the lumen of the catheter body while the core 104 rotates. The flexible seals 304 may be compressed on the core 104 with sufficient force to prevent leakage, while the console actuator can rotate the imaging core 104 at a rate that supports a high imaging frame rate via the proximal interface 308. In some embodiments, the flexible seals 304 may be assembled inside the connector hub 300 to ensure accurate mating. The connector hub 300 can include one, two, three or more flexible seals 304. In some embodiments, the flexible seals 304 may have a circular cross-section or an "X" cross-section as shown in Figure 3B.

[0148] The connector hub 300 may also include one or more seal housing components 306. In various embodiments, the seal housing 306 may be circular, round, elliptical, triangular, square, rectangular, and / or polyhedral in shape. For example, as shown in the exemplary embodiment of Figure 3B, two seal housing components 306 may be configured to house and capture the flexible seal 304 in the connector hub 300 and the proximal interface 308. The inner diameters of the seal housings 306 may be fitted tightly and precisely to ensure that adequate pressure is applied to the flexible seal 304. Adequate pressure allows the imaging core 104 to rotate with less friction and prevents the acoustic coupling medium from leaking through the flexible seal 304. In some embodiments, an adhesive applied to the outer circumference of the flexible seal 304 prevents leakage around the flexible seal 304.

[0149] In a typical clinical environment, the pressure difference on both sides of the flexible seal 304 can generally be small, so there is little force to push the medium or draw in air. However, outside of the clinical setting, especially during product transport, catheters can be subjected to extreme temperature and / or atmospheric pressure fluctuations, which can introduce air into the medium or cause the seal 304 to rupture. For example, extreme increases or decreases in the temperature of the acoustically coupled medium may cause it to expand or contract, or change from liquid to solid, increasing or decreasing the enclosed volume, causing an increase or decrease in fluid pressure, and then returning to its original volume after extreme exposure. This change in volume and / or pressure can be addressed by the flexibility and / or compressive force of the seal 304 to prevent air bubbles from being drawn into the lumen (in the case of a pressure drop) or fluid leakage (in the case of a pressure rise). Air entering the lumen can move to the distal transducer and degrade image quality. In some embodiments, a double-seal housing provides precise assembly and sealing. In one embodiment, a single housing on the proximal side only may also be used.

[0150] Figure 4 is a lateral cross-sectional view of the distal end of the elongated member 400 of the catheter 101. The distal end may include an exit port configured to be sealed after the imaging lumen of the catheter body is filled with an acoustic coupling medium according to one embodiment. The elongated member 400 may include a lumen 402 containing the distal port 404. As described in relation to Figure 5 below, the lumen 402 may be filled with a coupling medium, and the distal port 404 may be sealed to reduce or eliminate air bubbles from the lumen and reduce or eliminate the need to flush the catheter lumen. In some embodiments, the distal plug 406 can be attached to a removable wire 408. In one embodiment, the distal plug 406 is made of a polymer material. In various embodiments, the distal plug 406 can be made of Pebax (polyether block amide), nylon or other polymer material so that bonding and / or heat sealing of the plug to the catheter body is effective. In some embodiments, the distal plug 406 may be molded to conform to the shape of the distal port 404 and the distal compartment of the imaging lumen 402. The removable wire 408 may be made of NiTi (nitinol), stainless steel, or another flexible material.

[0151] In one embodiment, the wire 408 may be fed through the lumen 402 from the proximal port at the proximal end toward the distal port 404. In one embodiment, the wire 408 is configured to exit the distal port 404, leaving the distal plug 406 in the distal portion of the lumen 402. Once the filling process is complete and all air bubbles have been removed from the lumen 402, the distal plug 406 may be bonded or adhered to the wall of the lumen 402. The distal plug 406 may be drawn into the distal port 404 by the wire 408 so that the distal plug 406 seals the distal port 404. In some embodiments, heat can be applied to the distal end of the elongated member 400 to melt the distal plug 406 together with the wall of the lumen 402 and / or bond it to the wall of the lumen 402. In some embodiments, an adhesive can be inserted into the distal port 404 to bond the plug 406 to the wall of the lumen 402. After the distal plug is joined to the lumen 402, the wire 408 can be removed from the plug 406.

[0152] In one embodiment, the wire 408 may be fed through the imaging lumen 402, starting from the proximal port at the proximal end of the catheter and toward the distal port 404. In one embodiment, the wire 408 is configured to exit the distal port 404, leaving the distal plug 406 in the distal compartment of the imaging lumen 402. The wire 408 can be removed before the filling process begins. The air channel left in the distal plug 406 can form an effective vent, providing a path for the binding medium to exit through the distal port 404 during the medium filling process. In one embodiment, the space between the distal plug 406 and the imaging lumen 402 further provides a path for the binding medium to exit. Once the filling process is complete and all air bubbles have been removed from the imaging lumen 402, the distal port 404 can be closed and the imaging lumen 402 can be sealed. In some embodiments, heat can be applied to the distal end of the elongated member 400 surrounding the distal plug 406 for a closure process, melting the distal plug 406 together with the wall of the imaging lumen 402 and / or bonding it to the wall of the imaging lumen 402. The heat can also close the vent created by the channel from the removed wire. In some embodiments, adhesive can be inserted into the distal port 404 to bond the plug 406 to the wall of the lumen 402, forming an effective seal of the imaging lumen 402. In other embodiments, to close the vent, the wire 408 inside the distal plug 406 remains in place until the medium filling process is stopped and the distal plug is fixed in the imaging lumen 402. During the filling process, the space around the outside of the distal plug can be an effective vent, providing an exit from the distal port 404 for the moving binding medium. Once filling is complete without bubbles, heat can be applied to fuse the distal plug to the imaging lumen, and then the wire is removed. To close the channel formed by removing the wire, either further heat or adhesive can be applied. In another embodiment, the wire 408 is removed after filling is complete. The distal plug can then be fused to the imaging lumen, and heat can be applied to close the channel formed by removing the wire.

[0153] In one embodiment, an optional additional rapid-replacement guidewire lumen 410 is shown in Figure 4. In various embodiments, the distal plug 406 is used without the rapid-replacement lumen 410.

[0154] Figure 5 shows a process 500 for sealing a binding medium into the lumen of an IVUS catheter according to one embodiment. In some embodiments, process 500 prevents, reduces, and / or eliminates the formation or trapping of air bubbles in the lumen during the filling process, thereby enabling the creation of higher quality ultrasound images. The process 500 shown in Figure 5 is an exemplary process. In some embodiments, process 500 may include more or fewer steps. In some embodiments, one or more steps of process 500 may be performed in a different order or simultaneously with one or more of the other steps of process 500.

[0155] In some embodiments, the degassing process includes exposing an acoustic fluid to vacuum pressure for a period of time. In one embodiment, the degassing process can be initiated by providing a degassing device. The degassing device may include a container, a vacuum pump, a magnetic stirring hot plate, and a syringe. The container may be connected to the vacuum pump via a tubing section and a first valve, such as a directional valve. The container may be connected to the syringe via a second valve, such as a stopcock valve. The acoustically coupled medium may be placed in the container and held for a first period. The first period may be a set period or may continue until the acoustically coupled medium reaches an air saturation threshold. After the first period, the acoustically coupled medium may be held at vacuum pressure for a second period. The second period may be a set period, as described later, or may continue until the acoustically coupled medium reaches a desaturation threshold. Once the acoustically coupled medium reaches a desaturation threshold, the medium may be transferred to the syringe via the tubing section and the second valve. In one embodiment, the magnetic stirring plate is a hot plate, and the degassing process also includes heating the acoustically coupled fluid medium to reduce the fluid viscosity and facilitate the subsequent filling process.

[0156] The IVUS catheter may be filled with a degassed acoustic coupling medium. In some embodiments, the filling process can be initiated by providing an IVUS catheter filling device which may include a fluid pump such as a syringe pump device, a catheter heating plate, and / or a microscope. The IVUS catheter may be placed in the catheter heating plate and heated to a target catheter temperature. The catheter heating plate may include a notch for receiving the IVUS catheter. The notch may be "S" shaped, spiral, a straight path, etc., and may be molded based on one or more characteristics of the IVUS catheter.

[0157] In one embodiment, a vacuum pump is attached to the distal outlet port to remove air from the catheter imaging lumen, and then the inlet port is opened (e.g., via a valve) to allow the medium to be drawn into the lumen. In one embodiment, a positive pressure pump may be used instead of, or in addition to, the vacuum pump to push the medium into the imaging lumen. In one embodiment, a peristaltic pump is a useful pumping mechanism for pushing the medium.

[0158] In one embodiment, process 500 may include step 502, where the acoustically coupled medium is degassed. The coupled medium can be degassed by vacuum degassing, sonication, sparging, or a combination thereof. In one embodiment, vacuum degassing is used due to its simplicity and effectiveness. Advantageously, in some embodiments, degassing the coupled medium prevents, reduces, or eliminates the formation of bubbles in the coupled medium during transport or treatment. Undegassed medium is typically saturated with dissolved gases in the surrounding environment, and these gases can escape from the solution during the filling process, potentially generating bubbles during and after the filling process. Bubbles can adhere to surfaces, especially uneven surfaces, making it difficult to completely remove air from the catheter lumen. After degassing, the coupled medium can remain unsaturated for a certain actual period, e.g., the actual filling period. The catheter lumen can be filled during the actual filling period. By degassing the coupled medium, the risk of air escaping from the solution during the filling process is minimized, and any bubbles present can be dissolved.

[0159] In one embodiment, the process may proceed to step 504, where the binding medium is heated. Heating the binding medium can further remove dissolved gases from the binding medium, reduce the viscosity of the medium, and shorten the time required to fill the catheter lumen. The binding medium may be heated by conduction, convection, radiation, or a combination thereof. In some embodiments, the binding medium may be heated in a container used to degas the binding medium. In some embodiments, heat may also be applied to the tubular portion used to fill the catheter lumen and / or the catheter itself, thereby heating the interface surrounding the binding medium.

[0160] In one embodiment, process 500 proceeds to step 506, where the binding medium is inserted into the lumen of the elongated member. The binding medium may be inserted by applying positive pressure to a proximal filling port connected to the lumen, thereby pushing the binding medium into the lumen. For example, the tubing may be attached to the proximal port and lumen of the elongated member, and a positive pressure pump can be used to push the binding medium through the tube into the lumen. The positive pressure pump may be a syringe pump, a positive displacement pump, or any other pump capable of applying a controlled pressure suitable for filling the imaging lumen. According to some embodiments, a peristaltic pump can be used to apply a constant positive pressure. In some embodiments, the binding medium may be inserted by applying negative or vacuum pressure to the distal port of the elongated member. For example, a vacuum pump can be attached to the distal port to remove air from the lumen, and then the proximal valve can be opened to draw the binding medium into the lumen. In some embodiments, a combination of positive and vacuum pressure can be used to insert the binding medium into the lumen. For example, a vacuum pump can be attached to the distal port to remove air from the lumen, the valve at the proximal port can be opened, and positive pressure can be applied to the binding medium with the pump to push the medium into the lumen.

[0161] In some embodiments, the binding medium is inserted into the lumen during the actual filling period. The actual filling period can be defined as the set period during which the binding medium remains unsaturated with air after the degassing process. The actual filling period may depend on the type of medium. The actual filling period can be calculated by placing an oxygen sensor in the binding medium and measuring the oxygen in the medium in comparison to the proportion of oxygen in the ambient air. For example, measuring the oxygen content in the binding medium as a function of time can be performed to quantify how quickly ambient air is absorbed into the medium. In some embodiments, to support an effective degassing method, it is provided that the actual filling period be set to ensure that only a small amount of ambient air is absorbed into the medium. For example, in PEG400, a fluid with a viscosity of about 100 cP when properly degassed, the actual filling period can be less than 2 hours, supporting a manufacturing process that can be used to fill the lumen within 1 hour immediately after any degassing step is completed.

[0162] In one embodiment, process 500 can proceed to step 508, where the binding medium can be agitated by oscillating or vibrating one or more of the surrounding catheter components. For example, the binding medium can be agitated by moving the imaging core 104 within the binding medium. For example, the binding medium can be agitated by using the vibration of the catheter to rotate the imaging core 104 and / or move the core longitudinally within the lumen. In one embodiment, the catheter is agitated on a vibrating surface and / or receives ultrasonic energy.

[0163] Next, the process optionally proceeds to step 510, where the catheter body may be oriented at a certain angle (for example, an angle between 0 and 90 degrees, between the horizontal (e.g., 0 degrees) and the vertical (e.g., 90 degrees), for example, oriented at a positive angle above horizontal). In one embodiment, the catheter is optionally positioned at an angle above horizontal and up to vertical, which can be performed before the binding medium is inserted. The catheter body may be oriented between horizontal and vertical such that the distal end of the elongated member is above the proximal end of the catheter body. In various embodiments, catheter orientation at any positive angle above horizontal can be used to help any bubbles exit the catheter lumen. In one embodiment, oriented the catheter at a positive angle (e.g., up to vertical) can move bubbles upward from the distal port to help release bubbles and visualize an acceptable filling process. In some embodiments, the catheter body may be oriented vertically such that the distal port is the highest point of the lumen. In one embodiment, the catheter shaft is oriented above horizontal at an angle smaller than vertical, where vertical is 90 degrees. In some embodiments, any positive angle above horizontal can facilitate air removal at an angle based on the type of medium and process parameters shown in Figure 5. Optionally, no angle, angle 0 may be implemented if air bubbles are effectively removed without this step 510 for the selected binding medium and other process parameters.

[0164] Process 500 can proceed to step 512, where the insertion of the binding medium is stopped. The insertion of the binding medium may be stopped when the lumen is sufficiently filled with the binding medium. In some embodiments, the insertion of the binding medium may be stopped when the imaging lumen is full and the binding medium is visually inspected to be free of bubbles. In some embodiments, the visual inspection may include a microscope with a magnification of at least 10x. Magnifications of 10x, 30x, 50x, and up to 100x may help identify when there are no more bubbles in the filling medium. To completely remove all bubbles, the distal end of the catheter may be visually inspected. The size of the bubbles initially present in the medium may depend on the geometric shape of the internal components in contact with the medium. In some embodiments, bubbles larger than at least 10-20 μm in diameter are removed. In some embodiments, if the amount of bubbles is less than 10-20% of the active surface area of ​​one or more transducers, microbubbles with a diameter of less than 10-20 μm are unlikely to have a significant impact on the imaging performance of the IVUS. In some embodiments, the insertion of the binding medium can be stopped after a set period has elapsed. For example, the set period may have a duration of 5 to 30 minutes (e.g., 5, 10, 15, 20, 25, and 30 minutes, and any range or value therein). In some embodiments, both the volume of the lumen being filled and the viscosity of the selected medium may affect the filling period. In some embodiments, longer catheters may take longer to fill the same lumen diameter.

[0165] Next, process 500 can proceed to step 514, where the inner lumen is sealed. As described above in relation to Figure 4, the distal port may be sealed with a plug. The plug can be attached to a flexible wire. The wire may be provided through the inner lumen from the proximal port toward the distal port. The wire can exit the distal port, leaving the distal plug in the distal section of the lumen. In some embodiments, the wire and distal plug may be inserted into the lumen before the lumen is filled with a binding medium (step 506). The distal plug may be pulled into the distal port by the wire so that the distal plug seals the distal port. In some embodiments, the distal plug may be bonded to the wall of the inner lumen. Heat can be applied to the distal end of an elongated member to bond and / or fuse the distal plug to the wall of the inner lumen. In some embodiments, an adhesive can be inserted into the distal port to bond the plug to the inner and / or outer wall of the inner lumen. After the distal plug has been bonded to the inner lumen, the wire can be removed from the plug. In some embodiments, the medium inlet port of the connector hub (e.g., fluid filling port) may be sealed using a plug or adhesive. In various embodiments, the adhesive is a single component, one part, two parts, or multiple parts, and is an epoxy, acrylic, cyanoacrylate, or ethyl cyanoacrylate adhesive. In various embodiments, the adhesive may be cured, for example, chemically, by light, or ultraviolet light. In some embodiments, the adhesive maintains its adhesive properties with sufficient adhesive strength after sterilization processes such as steam, autoclave, gamma and / or electron beam (e-beam) sterilization. Examples of adhesives include options from Loctite, e.g., 3311, 3922, 4310, 4311, EA-M-21HP, and EA-M-31CL. These examples have good adhesive properties and maintain sufficient adhesive strength even after gamma and / or electron beam sterilization. In some embodiments, the filling port may be self-sealing, i.e., the port is reliably sealed by removing the filling nozzle.

[0166] In some embodiments of process 500, step 502 may be performed simultaneously. In some embodiments of process 500, steps 504, 506, 508 and / or 510 may be performed simultaneously.

[0167] Advantageously, process 500, according to some embodiments, significantly reduces the risk of undetectable bubbles appearing and degrading image quality. Since the space inside and around the drive shaft along the entire length of the catheter is a space where air may not be easily and completely removed, the degassed binding medium helps remove air from hidden cavities. Bubbles can also be present inside other cavities or interfaces inside the main lumen of the catheter. These other cavities are often difficult to inspect, and it may be impossible to inspect for bubbles during and after the filling process. Bubbles may be present after filling, undetectable, and appear during subsequent clinical use.

[0168] Process 500 allows the inner lumen to be filled with an acoustically coupled medium that minimizes trapped air during a single setup procedure according to several embodiments. Process 500 represents a series of steps within the manufacturing process and may allow the catheter to be shipped in a "ready for use" state so that it can be quickly inserted into a console. The coupled medium does not contain bubbles or even small amounts of microbubbles and does not generate bubbles during the procedure, so high-quality ultrasound images can be captured without flushing the catheter with saline. Subsequently, in some embodiments, procedure time is reduced, higher quality diagnostic images are captured, and patient outcomes are improved.

[0169] Figure 6 shows an exemplary process 600 for sealing a binding medium in the inner lumen of an IVUS catheter. The process 600 shown in Figure 6 is exemplary. In some embodiments, the process 600 may include more or fewer steps. In some embodiments, one or more steps of the process 600 may be performed in a different order or simultaneously with one or more of the other steps of the process 600.

[0170] Process 600 may begin with step 602, in which the binding medium is degassed. Step 602 may be the same as step 502 described above. Next, process 600 may move to step 604, where the binding medium may be pushed into and / or drawn into the lumen of the catheter through the proximal inlet port by a vacuum pump located at the distal outlet port of the catheter. The binding medium may be heated. Process 600 may move to step 606, where the filling of the binding medium into the inner lumen of the catheter may be stopped once all air has been removed from the inner lumen. Step 606 may be the same as step 512. Next, process 600 may move to steps 608 and 610, where the distal outlet port and proximal inlet port can be sealed, respectively. Step 608 may include the process for sealing the distal port described above in relation to step 514. Step 610 may include the process for sealing the proximal port described above in relation to step 514.

[0171] Figure 7 shows an exemplary process illustrating the process 700 for sealing a binding medium in the inner lumen of an IVUS catheter. The process 700 shown in Figure 7 is exemplary. In some embodiments, the process 700 may include more or fewer steps. In some embodiments, one or more steps of the process 700 may be performed in a different order or simultaneously with one or more of the other steps of the process 700.

[0172] Process 700 can begin with step 702, in which the binding medium is degassed. In one embodiment, the binding medium is a binding fluid. Step 702 may be similar to steps 502 and 602 described above. A filling device, such as a motor or pump, may be attached to the filling port of the proximal hub of the imaging catheter. Process 700 can then proceed to step 704, in which the binding medium may be pushed into the lumen of the catheter through the proximal inlet port and / or drawn into the lumen by a vacuum pump located at the distal outlet port of the catheter. The binding medium may be heated. Process 700 can then proceed to step 706, in which the internal imaging core 104 can be moved to remove air. Step 706 may be similar to step 508, in which the binding medium can be agitated by using catheter vibration to rotate the internal imaging core 104 and / or move the imaging core 104 longitudinally within the internal lumen. Process 700 may proceed to step 708, where all air is removed from the inner lumen and the filling of the binding medium into the inner lumen of the catheter may be stopped. Step 708 may be the same as steps 512 and 606. Next, process 700 may proceed to steps 710 and 712, where the distal exit port and proximal inlet port can be sealed, respectively. Step 710 may include the process for sealing the distal port as described above in relation to steps 514 and 608. Step 712 may include the process for sealing the proximal port as described above in relation to steps 514 and 610.

[0173] Figure 8 shows an embodiment of the catheter 101 of the IVUS system 100. The catheter 101 may include a catheter body 102, an imaging core 104, and a proximal connector hub 870 having a filling port 860. The imaging core 104 (having a transducer 105) may be positioned in the imaging lumen of the catheter body 102, and the catheter body 102 may include a distal tip 810, an acoustic window 820, a catheter working length portion 835 (e.g., 100-200 cm), a hydrophilic coating 830 (e.g., distal 20-80 cm), an intermediate shaft hub 840, a proximal extension portion 850 (e.g., 100-150 cm), and a proximal strain relief 855, and may be connectable to the proximal connector hub 870 having a filling port 860. In various embodiments, the hydrophilic coating is present on the outer and / or inner surface of the catheter (e.g., inside the lumen). In some embodiments, the hydrophilic coating is not present on the outer surface of the catheter. In some embodiments, the hydrophilic coating is not present on the inner surface of the catheter (e.g., inside the lumen).

[0174] Figure 9 shows an embodiment of an IVUS system 100 having various subassemblies for an IVUS catheter 101, which includes a catheter body 102 such as an imaging core 104, a distal catheter jacket along the catheter working length 835, a proximal extension portion 850, and a proximal hub connector 870.

[0175] Figure 10 shows an embodiment of an imaging core 104 subassembly having a transducer 105 and a transducer housing 103, a coaxial electrical connector cable 1000, and a coil 1010. The coil 1010 (e.g., a torque coil, drive shaft, drive cable, drive coil, drive system, drive actuator, etc.) can support the uniform rotation of the transducer 105 in a lumen filled with an acoustic medium. The imaging core 104 can be configured to minimize bubbles in or around the transducer 105. In one embodiment, the imaging core 104 subassembly may include one or more apertures or holes to improve the filling process.

[0176] Figure 11 shows the distal tip 810 of the RX embodiment of the catheter 101 of the IVUS system 100 according to one embodiment. In various embodiments, the distal tip 810 may be flexible, non-traumatic, and robust (having the ability to cross an occlusion without deformation), and may include a radiopaque marker 812 at the tip. In one embodiment, the distal tip includes an acoustic window 820 on the transducer imaging surface. The distal tip may be configured to seal the binding medium within the catheter. In one embodiment, the distal tip includes a plug 406 for closing a bleed hole / port or vent hole / port at the distal end of the imaging lumen 402. The distal tip and plug assembly may be formed with a small wire, which is subsequently removed, to form a vent or outlet port to allow air to escape during the fluid filling process. Once fluid filling is complete, the vent or outlet port can be closed. In one embodiment, the distal tip 810 includes a plug 406 reinforcing the RX guidewire lumen 204. In one embodiment, the RX port includes a lumen 204 with a length of 1 to 3 cm (e.g., 1.0, 1.5, 2.0, 2.5, 3.0 cm) to support the insertion of a guidewire into a durable and flex-resistant lumen. In one embodiment, the distal tip has a tapered distal tip and is durable. In one embodiment, the distal tip includes a radiopaque (RO) marker 812 at or near the distal end. In one embodiment, the distal catheter jacket 835 has a flexible distal region and a more rigid, pressable proximal region. In one embodiment, the distal catheter jacket 835 has an RO marker along the shaft. In one embodiment, the tip and shaft RO markers may be made of radiopaque polymer materials such as tungsten-containing Pebax and / or nylon to improve the visibility and / or opacity of the distal tip and / or provide measurement markings during clinical procedures. The RO marker may also be platinum, gold, iridium, or an alloy thereof, and in various embodiments, it may be bonded, swaged, sealed, or otherwise fixed to the distal tip and / or the catheter body 102.

[0177] Figure 12 shows an embodiment of the distal tip 810 of the IVUS system 100, in which the 1 mm interval scale of the measuring ruler is positioned next to the distal section of the catheter.

[0178] Figure 13 shows an over-the-wire (OTC) embodiment of the catheter 101 of the intravascular ultrasound system 100. The catheter 101 includes a catheter body 102 and an imaging core 104 (having a transducer 105) configured to connect to a proximal connector hub 870 having a filling port 860. The catheter body may include a distal tip 810, an acoustic window 820, a catheter working length (e.g., 90–130 cm) of the distal catheter jacket 835, a hydrophilic coating 830 (e.g., distal 20–60 cm), an intermediate shaft hub 840, a guidewire exit port 845, a proximal extension portion 850 (e.g., 120–160 cm), and a proximal strain relief 855 configured to connect to the proximal connector hub 870 having a filling port 860. In various embodiments, the hydrophilic coating is present on the outer and / or inner surface (e.g., inside the lumen). In some embodiments, the hydrophilic coating is not present on the outer surface of the catheter. In some embodiments, the hydrophilic coating is not present on the inner surface of the catheter (e.g., inside the lumen).

[0179] Figure 14 shows various subassemblies for the IVUS catheter 101, including the imaging core 104, the distal jacket along the catheter working length 835, the proximal extension portion 850, and the proximal hub 870.

[0180] Figure 15 shows the distal catheter jacket portion 835 of the catheter body 102 of Figure 14 according to one embodiment. In one embodiment, the distal catheter jacket 835 includes a guidewire lumen 847 and an imaging lumen 218, and has a flexible distal region 860, a more rigid, pressable proximal region 870, and one or more radiopaque (RO) markers 900 located at the distal end and along the shaft. The imaging lumen 218 can accommodate an imaging core 104 and an acoustic coupling medium.

[0181] Figure 16 shows a distal tip 810 according to one embodiment, having an acoustic window 820, a plug 406, a guidewire lumen 847, and an imaging lumen 218. In various embodiments, the distal tip may be flexible, non-traumatic, and robust (having sufficient rigidity to cross an occlusion without bending or collapsing) and may include one or more radiopaque markers, such as a radiopaque tip marker. In one embodiment, the distal tip includes an acoustic window on the transducer imaging plane. The distal tip is configured to seal the binding medium within the catheter. In one embodiment, the distal tip includes a plug for closing a bleed hole / port or vent hole / port, such as an exit port that is sealed after a fluid filling step. In one embodiment, the distal tip has a tapered distal tip and is durable. In one embodiment, the distal tip includes a Pebax with one or more durometers with an optional tungsten distal marking band loading to provide visibility of the distal tip under fluoroscopy.

[0182] Figure 17 shows a cross-section of the catheter shaft (including the jacket portion) 835 of the catheter body 102 according to one embodiment of the catheter 101 of Figures 13-16, showing the guidewire lumen 847 and the imaging lumen 218. The cross-section is shown in the configuration of Figure 8, which has a uniform wall thickness around the transducer portion of the catheter shaft, according to one embodiment, and in a more robust elliptical cross-section for the rest of the shaft. In one embodiment, a portion of the catheter includes a substantially uniform polymer thickness within the acoustic window of the catheter 101 around the transducer portion configured for more consistent imaging.

[0183] Figure 18 shows an intermediate portion of the catheter body 102, including an intermediate shaft hub 840 connecting the distal shaft working length 835 and the proximal extension portion 850 of the imaging catheter 101, according to one embodiment, as shown in Figure 13. The proximal extension portion can optionally connect the distal working length 835 to the proximal connector / hub 870. In one embodiment, the proximal extension portion 850 has a single imaging lumen continuous with the imaging lumen 218 of the distal working length portion 835. Thus, it houses the proximal half of the imaging core 104 and the acoustic coupling medium. The proximal extension portion is configured for a bending radius of 2 to 5 inches (e.g., 2, 2.5, 3, 3.5, 4, 4.5, 5 inches and values ​​within those). In one embodiment, the intermediate shaft hub includes a guidewire exit port continuous with the guidewire lumen 847 of the distal shaft working length 835. In one embodiment, the intermediate shaft hub is connected to the two lumens of the distal working length 835 of the catheter shaft via the intermediate shaft Y-hub. The skive of the double lumen extrusion can connect the guidewire lumen 847 to the guidewire exit port 845. The material of the intermediate shaft hub can include Pebax, polycarbonate, polycarbonate / ABS, nylon, transparent material, and adhesives such as cyanoacrylate or other suitable adhesives.

[0184] Figure 19 shows a proximal hub 870 of a catheter 101 according to one embodiment. In various embodiments, the proximal hub 870 supports (i) connecting the catheter shaft to a CIM latch mechanism, (ii) connecting the imaging core 104 to a CIM motor, (iii) connecting the electrical connection between the coaxial cable and the CIM, (iv) connecting the electrical ID (EID) 910 to the catheter interface module, and / or (v) an acoustic coupling medium filling process that seals the acoustic medium within the device. In one embodiment, the catheter jacket is bonded to the proximal housing, and a proximal strain relief 855 provides a transition to the CIM connection 308. In one embodiment, the proximal hub housing includes one or more seal housings / seals 304, a PCB substrate 912, a filling port 860, and a latch mechanism. In one embodiment, the drive shaft of the imaging core 104 is coupled to a drive hub 920 that is coupled to a motor in the catheter interface module. In one embodiment, an internal PCB enables electrical connections. Materials can include Pebax, polycarbonate, polycarbonate / ABS, nylon, and transparent materials.

[0185] Figure 20 shows the distal end of the catheter 101 according to various embodiments. In various embodiments, the acoustic coupling medium 109 of the catheter 101 has acoustic properties similar to blood, is biocompatible, and is configured to fill the imaging lumen without bubbles (or by minimizing bubbles) within the imaging plane of the acoustic window, thereby reducing or eliminating bubbles that may interfere with imaging. In various embodiments, the volume of the acoustic coupling medium can be as low as 0.5 mL and as high as 4 mL within the catheter (e.g., up to 4, 3.9, 3.7, 3.5, 3.3, 3.1, 3.0, 2.8, 2.6, 2.4, 2.1, 1.9, 1.7, 1.5, 1.0, 0.5 mL and further volumes therein). In one embodiment, the acoustic coupling medium is colored to facilitate monitoring of the filling process and inspection for bubbles. Mediums with superior acoustic properties have sound density and velocity values ​​similar to those of the catheter jacket material in some embodiments. Large differences in acoustic density or velocity between the medium and the catheter jacket can lead to undesirable strong acoustic reflections and refractive acoustic pulses, potentially degrading image quality. In some embodiments, the acoustic coupling medium has a sound velocity value configured for improved lateral imaging performance. In some embodiments, the acoustic coupling medium has a sound velocity value configured for improved lateral performance. In one embodiment, the geometric shape of the rotating element catheter can include a focusing lens for ultrasound, formed by a gently convex circular layer of material on the transducer surface having a sound velocity slightly lower than the material being imaged. In one embodiment, a tightly curved shell (catheter body) and inner material (binding medium) with a high sound velocity can be selected to be close to, and possibly even higher than, the material being imaged. In one embodiment, the geometric design of a rotating catheter having a thin, relatively high-velocity catheter body and the binding medium inside can be configured to have a considerably advantageous focusing effect. This embodiment can be configured to be unexpected and surprising, as the focusing lens for ultrasound is formed by a gently convex circular layer of material on the transducer surface having a sound velocity slightly lower than the material being imaged.In one embodiment, the high-velocity, tightly curved shell (catheter body) and inner material (binding medium) can be selected to be close to or even higher in velocity than the material being imaged. In some embodiments, the medium comprises one of polyethylene glycol (PEG), PEG with some water, water, saline solution, glycerin, and natural oil. The proportion of non-PEG components may be 80-20% (e.g., 80%, 70%, 60%, 50%, 40%, 30%, 20% and overlapping values ​​and ranges therein), and in certain embodiments, it may be in the range of 50-30% (e.g., 50%, 45%, 44%, 43%, 42%, 41%, 40%, 39%, 38%, 37%, 35%, 35%, 30% and overlapping values ​​and ranges therein), due to the latter having a lower tendency for dissolved gases.

[0186] Figure 21 shows the assembly process of the proximal hub 870 according to one embodiment. In various embodiments, the steps include: installing and joining the seal and / or seal housing, electronic ID, and ultrasonic signal PCB for electrical coaxial connection within the proximal hub housing; sliding the ultrasonic signal PCB on the drive shaft of the imaging core 104; soldering the coaxial cable to the ultrasonic signal PCB; joining the PCB to the drive shaft using conductive epoxy resin; installing the drive shaft / PCB within the drive hub; fixing it using adhesive; assembling the drive shaft / imaging core 104 into the hub housing / seal; applying vacuum grease around the seal area; positioning the imaging core 104 within the catheter jacket; joining the jacket to the proximal hub housing; installing and joining the strain relief; and / or attaching a one-way valve to the filling port.

[0187] Figure 22 shows an acoustically coupled medium filling process according to one embodiment. In various embodiments, the steps may include degassing the medium in a vacuum chamber; filling the catheter through the proximal filling port; sealing the vent (e.g., the outlet port) at the distal tip (e.g., using a heat seal, heat shrink tubing, adhesive, etc.); closing the filling port (e.g., the inlet port) with a cap; and inspecting whether there are no or minimal bubbles, no leaks, and the catheter is completely filled. The degassing procedure may be time-sensitive. In one embodiment, a sealed container is used to limit regassing and contamination of the fluid during handling and the filling process. In one embodiment, the fluid filling process may take 5 to 60 minutes (e.g., 5 to 20, 20 to 40, 30 to 50, 40 to 60 minutes, and an overlapping range therein) at a pressure of, for example, 40 to 100 psi (e.g., 40 to 60, 60 to 80, 70 to 100 psi and an overlapping range therein).

[0188] Figure 23A shows an exploded view of the catheter connector hub 2300 of catheter 101 according to one embodiment. The connector hub 2300 includes a filling port cap 2302 and a filling port cover 2304. In some embodiments, the connector hub 2300 may be similar to the connector hub 300 shown in Figures 3A, 3B, and 19 according to some embodiments. The connector hub 2300 can be mated with a CIM. According to some embodiments, the connector hub 2300 may include one or more components of the connector hub 300.

[0189] In some embodiments, the catheter connector hub 2300 (i) latches securely to the CIM 115 or console 118 and is easily released during removal, (ii) mates with the CIM receptacle and makes an electrical connection, (ii) mates with the motor drive shaft in the CIM receptacle and maintains the concentric rotation of the rotating shaft, (iv) seals the acoustic coupling medium 109 inside the imaging lumen of the catheter 101 distal to the seal, and / or (v) supports a filling port for the acoustic coupling medium. The connector hub 2300 may be located at the proximal end of an IVUS catheter, including an imaging core 2306 attached to the drive shaft 2308. The imaging core 2306 and drive shaft 2308 may be located inside the imaging lumen of the catheter body 2303 of the IVUS catheter 101. The drive shaft 2308 may be a stainless steel hypotube and may be fixed to the imaging core 2306. In some embodiments, the IVUS catheter may include a strain relief component 2310. As most clearly shown in Figures 24A, 24B, and 24C, strain relief components may be arranged concentrically around the distal end of the connector hub 2300 and the proximal end of the catheter body 2303. In some embodiments, the strain relief component 2310 may be a component of the connector hub 2300. The strain relief component 2310 can reduce or prevent bending and excessive local strain in the proximal portion of the IVUS catheter. For example, the strain relief component 2310 can reduce or prevent bending while a physician handles the IVUS catheter before, during, or after an IVUS procedure. In some embodiments, the strain relief provides mechanical strength that allows the catheter body 2303 to bend around the rigid proximal connector hub housing without hindering proper rotation of the imaging core 2306. In some embodiments, the distal end of the strain relief 2310 is tapered to provide a gradual rigidity transition to the proximal catheter body 2303.In some embodiments, the strain relief extends approximately 5–10 (7–9 cm) distal to the connector hub 2300 to allow the user to firmly hold the strain relief portion on the shaft while connecting the connector hub 2300 to the CIM 115 or console 118 without bending the IVUS catheter.

[0190] The connector hub 2300 may include a hub housing 2301, a seal 2312, a drive bushing 2314, a drive hub 2316, a drive hub pin 2318, and / or an electronic identification (EID) printed circuit board (PCB) 2320. In one embodiment, the EID PCB provides catheter identification and bidirectional communication with the catheter to the IVUS system console. The seal 2312 can seal the acoustic coupling medium within the imaging lumen of the IVUS catheter. The drive bushing 2314 may be concentrically positioned around the drive shaft 2308 and bonded to the inner surface of the hub housing 2301 of the connector hub 2300. In some embodiments, the drive bushing may be injection molded and / or machined. In one embodiment, the drive bushing 2314 is a single component configured to be adhesively fixed to the hub housing 2301 and to prevent leakage of the coupling medium. In one embodiment, the drive bushing 2314 is configured to capture the seal 2312 within the seal housing or receptacle in the hub housing 2301 when assembled to prevent leakage of the coupling medium. The drive bushing 2314 can center and align the drive shaft 2308 within the hub housing 2301 of the connector hub 2300. According to some embodiments, the drive bushing can hold or retain the seal 2312 in a predetermined position at the proximal end of the IVUS catheter. The drive bushing can maintain the position of the drive shaft 2308 concentric with the IVUS catheter. Advantageously, by maintaining the concentric position of the drive shaft 2308, the drive bushing can reduce wobble and / or uneven rotational strain (NURD) around the central drive shaft axis and prevent leakage of the acoustic coupling medium by maintaining uniform friction around the inner diameter of the seal 2312. In one embodiment, an adhesive sealant is applied to the inside of the drive shaft hypotube to prevent the bonding medium from leaking proximal through the drive shaft hypotube between the coaxial cable 2305 of the imaging core 2306 and the inner diameter of the hypotube.

[0191] The connector hub 2300 may include a drive hub 2316. The drive hub 2316 may be coupled to the proximal end of the drive shaft 2308. The drive hub 2316 may include an ultrasound signal PCB 2322. The ultrasound signal PCB 2322 can provide electronic communication between the transducer 105 of the IVUS catheter and the imaging console. The cable 2305 of the imaging core 2306 is electrically connected to the ultrasound transducer 105 at the distal end of the imaging core. The cable 2306 extends from the proximal end of the imaging core 2306 and is electrically connected to the ultrasound signal PCB 2322. The signal PCB 2322 may include one or more electrodes, for example, two, three, four, or more electrodes. In one embodiment, the cable 2305 is a coaxial cable having a metal inner conductor and an outer metal shield, with insulating material between the inner conductor and the outer shield, and around the outer shield. Electrically connecting the coaxial cable to the ultrasonic signal PCB includes separating the inner conductor from the outer shield, connecting the inner conductor to one electrode on the PCB, and connecting the shield to a separate electrode on the PCB. One or more electrodes may be coaxial electrical contacts that mate with corresponding pogo pins on the CIM. The pogo pins may be components of the CIM receptacle that can mate with the connector hub 2300. In this way, the ultrasonic transducer of the IVUS catheter 101 is electrically connected to the console 118 of the IVUS system 100.

[0192] In some embodiments, the drive hub 2316 may be held in place by a drive hub pin 2318. In some embodiments, the drive hub pin is a drive hub retaining pin. In some embodiments, the drive hub pin ensures alignment between the drive hub and the mating receptacle on the catheter interface module and prevents axial movement of the drive shaft 2308 and drive hub 2316 within the housing. The drive hub pin 2318 can protrude through the aperture of the housing 2301 of the connector hub 2300 and mate with the drive hub 2316. For example, as shown in Figure 23A, the drive hub pin 2318 protrudes through a hole on the side of the housing 2301 and mate with a groove in the drive hub 2316. The drive hub pin 2318 can maintain the position of the drive hub 2316 relative to the mating components of the CIM that mate with the connector hub 2300 and / or the drive hub 2316 when the catheter is connected to the CIM. According to some embodiments, the drive hub pin 2318 can prevent axial movement of the drive shaft 2308. In some embodiments, the connector hub 2300 may include an EID PCB 2320 for providing catheter identification and information, such as catheter model number and calibration information. In some embodiments, the EID PCB 2320 can provide electronic communication between the IVUS catheter and the console.

[0193] The connector hub 2300 may include a filling port 2324 that provides access to the imaging lumen of the IVUS catheter. In some embodiments, the filling port 2324 is integrated with the hub housing 2301 of the connector hub. The filling port is configured to allow easy connection to and disconnection from the filling nozzle of the manufacturing filling equipment, while reducing or eliminating the introduction of air pockets or bubbles into the IVUS system, and is configured to seal against filling pressure. According to some embodiments, the filling port 2324 may have a low profile design. The filling port 2324 can reduce the risk of air being introduced into the lumen and / or acoustic coupling medium of the IVUS catheter during the filling procedure. In some embodiments, the filling port 2324 may include a filling port seal 2326 located on the bottom surface of the filling port 2324.

[0194] Figure 23B shows a cross-sectional view of the proximal hub 2300 according to one embodiment. In some embodiments, once the catheter filling process is complete, the filling port 2324 can be sealed by inserting a filling port cap 2302 and a filling port cover 2304 into the filling port 2324, as shown in Figure 23B. The filling port cap 2302 and the filling port 2324 may include threaded components. For example, the filling port 2324 may be threaded, and the filling port cap 2302 may be screwed into the filling port 2324. In some embodiments, the filling port cap 2302 and the filling port 2324 may be connected using snap fitting and / or other mechanical means such as adhesive. Once inserted into the filling port 2324, the filling port cap 2302 can engage with the filling port seal 2326. In some embodiments, the filling port cap 2302 may include a recess located on its upper surface. The filling port cover 2304 can be inserted into the upper recess of the filling port cap 2302. In some embodiments, the filling port cover 2304 may be secured to the filling port cap 2302 using adhesive. In some embodiments, the filling port cover 2304 may be secured to the filling port 2324 using screw fittings, snap fittings, and / or adhesive to capture the filling port cap 2302. In some embodiments, the filling port cap 2302 is a seal that opens when the filling nozzle is installed during the filling process, but closes when the filling nozzle is removed and / or when the filling port cover 2304 is secured on the seal 2302.

[0195] Figure 24A shows a cross-sectional view of a connector hub 2300 having a strain relief component 2310 according to one embodiment. In some embodiments, the connector hub 2300 may include a hub latch 2402. The hub latch 2402 can secure the connector hub 2300 to a catheter interface module. The connector hub 2300 may include a filling port 2324, as discussed herein. In some embodiments, the strain relief component 2310 may be fitted to the distal portion of the connector hub 2300 and the proximal portion of the catheter body 2301. The strain relief component 2310 may be fitted to the filling port 2324 to conceal it. In some embodiments, the filling port is low profile and can be conveniently covered or concealed by the housing shell or strain relief so as not to attract the user's attention when not needed during catheter use. In some embodiments, the strain relief component 2310 may secure and / or a filling port cover within the filling port 2324. Figure 24B shows a distal isometric view of a connector hub 2300 having a strain relief component 2310 according to one embodiment. Figure 24C shows a proximal isometric view of a connector hub 2300 having a strain relief component 2310 according to one embodiment. In some embodiments, the strain relief component 2310 is joined to the connector hub 2300 by snap fitting, compression fitting, and / or adhesive.

[0196] In one embodiment, the filling port and / or filling port cap have a mechanism for fitting with the filling nozzle tip to secure the filling nozzle port and counteract the filling pressure. In some embodiments, the filling port and filling tip have a threaded fitting mechanism. Figure 25A shows a side view of a proximal hub 2502 and a filling nozzle 2504 according to one embodiment. The proximal hub 2502 may include a filling port 2506 for receiving an acoustic coupling medium via the filling nozzle 2504. The filling port 2506 can be connected to the filling nozzle 2504. In some embodiments, the filling port 2506 may include a seal 2508. The seal 2508 can prevent air from being introduced into the imaging lumen of the IVUS catheter and / or maintain the filling pressure.

[0197] The filling nozzle 2504 may include a proximal end 2510 and a distal end 2512. The filling port 2506 may be connected to the distal end 2512. The proximal end 2510 may include a handle or grip component that allows a person to hold the filling nozzle 2504. The proximal end 2510 may include at least one port. The port may be connected to a filling device configured to distribute an acoustically coupled medium, which can pass through the filling nozzle 2504 into the IVUS catheter imaging lumen and expel air from the lumen. The distal end 2512 of the filling nozzle 2504 may be mated with the filling port 2506. For example, the distal end 2512 may have a threaded component that mates with the threaded portion of the filling port 2506. Other mating mechanisms are also possible. In some embodiments, the distal end 2512 may receive a filling adapter 2514. The filling adapter 2514 may be mechanically coupled or bonded to the distal end 2512. The filling adapter 2514 can be mated with the filling port 2506. For example, the filling adapter 2514 may be a threaded component and, according to some embodiments, mate with a threaded component of the filling port 2506. In some embodiments, the filling adapter 2514 may be integrated with the distal end 2512.

[0198] Figure 25B shows a side view of the proximal hub 2502 and filling nozzle 2504 engaged for filling the proximal hub 2502 with binding medium according to one embodiment. The distal end 2512 of the filling adapter 2514 and / or the filling nozzle 2504 may engage with the filling port 2506 of the proximal hub, and the acoustic binding medium may be pushed or pulled into the imaging lumen of the IVUS catheter. As described above, the acoustic binding medium can pass through the imaging lumen from the filling port 2506 and exit from the distal port of the IVUS catheter. The distal port may be sealed as part of the filling process, as described above. After filling, the filling nozzle 2504 and filling adapter 2514 may be disengaged from the filling port 2506. The filling port cap 2302 may be screwed onto the filling port 2506 while pressing the seal 2508 to prevent the presence of air bubbles. When pressure is applied to the seal, some binding medium may begin to fill the port. The filling port cover 2304 can be inserted into and joined to the filling port cap 2302 to reduce or eliminate air bubbles from the port.

[0199] Figure 26A shows a filling port 2324 of a connector hub 2300 in the open position according to one embodiment. The filling port 2324 may include a seal 2602. The filling port 2324 can receive a filling port valve cap 2604. In some embodiments, the filling port valve cap 2604 functions as a dynamic valve that can be closed to seal the acoustic coupling medium in the IVUS catheter to reduce exposure to air. In one embodiment, a push-fill method can be used to reduce exposure of the IVUS catheter lumen to ambient air. In some embodiments, the filling port valve cap 2604 may include a conical distal tip 2606 having one or more apertures. One or more apertures may allow the acoustic coupling medium to pass through the filling port valve cap 2604 and enter the internal imaging lumen of the IVUS catheter through the seal 2602. The filling port 2324 can initially hold the filling port valve cap 2604 in the open position. In the open position, the filling port valve cap 2604 can be disengaged from the seal 2602 and the internal imaging lumen of the IVUS catheter. This open position may, according to some embodiments, allow the binding medium to be drawn into or pushed into the imaging lumen.

[0200] The filling port valve cap 2604 may include a recess for receiving the distal end 2512 of the filling nozzle 2504. In some embodiments, the filling port valve cap 2604 may include a threaded portion, such as a threaded recess, located on the upper or proximal side of the filling port valve cap 2604. The distal end 2512 may include a filling adapter 2514, be mechanically coupled to it, or be bonded to it. The filling adapter 2514 can engage and mate with the filling port valve cap 2604. For example, as shown in Figure 26A, the filling port valve cap 2604 may include a threaded portion in the central recess. The filling adapter 2514 may also include threaded components that can be screwed into, i.e., engaged with, the threaded portion of the filling port valve cap 2604. In some embodiments, other releaseable connection mechanisms may be implemented, such as spring-loaded fasteners or clips, rubber gaskets, etc.

[0201] Figure 26B shows a filling port 2324 of a connector hub 2300 engaging with a filling nozzle 2504 according to one embodiment. As described above, the filling port adapter 2514 can engage with a recess in the filling port valve cap 2604. In some embodiments, the engagement of the filling port adapter 2514 with the filling port valve cap 2604 initiates the flow of acoustically coupled medium from the filling nozzle 2504 to the internal imaging lumen of the IVUS catheter. Pressure can be applied to the IVUS catheter to force the acoustically coupled medium into the imaging lumen. In some embodiments, positive pressure may be applied to the filling nozzle 2504. In some embodiments, negative pressure, such as vacuum pressure, can be applied to the distal tip of the IVUS catheter. The acoustically coupled medium can flow through the filling nozzle 2504, through the filling port adapter 2514, through the filling port valve cap 2604, and through the seal 2602 to the internal imaging lumen of the IVUS catheter.

[0202] Figure 26C shows the filling port 2324 of the connector hub 2300 when the connector hub 2300 is disengaged from the filling nozzle, according to one embodiment. The filling port 2324 can seal the internal imaging lumen of the IVUS catheter. In some embodiments, the filling port valve cap 2604 may be sealed at the filling port 2324. By sealing the filling port valve cap 2604 and the filling port 2324, the acoustic medium can be contained within the filling port 2324, preventing air from entering the filling port 2324. In some embodiments, by sealing the filling port valve cap 2604 and the filling port 2324, the filling port assembly can be positioned in the "closed" position. In the closed position, the conical distal tip 2606 can be engaged with the seal 2602. Engagement of the conical distal tip 2606 can prevent air from entering the imaging lumen. After the filling port valve cap 2604 and the filling port 2324 are sealed, the filling adapter 2514 can be disengaged. For example, the filling adapter 2514 may be loosened from the filling port valve cap 2604. The filling adapter 2514 can be disengaged without introducing air into the filling port 2324 or the internal imaging lumen of the IVUS catheter.

[0203] Figure 26D shows a filling port 2324 of a connector hub 2300 in a closed or sealed position according to one embodiment. Figure 26D also shows a filling port 2324 and filling port valve cap 2604 in a closed position after a filling adapter 2514 has been disengaged from the filling port valve cap 2604, according to one embodiment. Removal of the filling adapter 2514 can apply nominal pressure to the filling port 2324, drawing an acoustic coupling medium into the filling port 2324 and preventing air from entering the filling port 2324. In some embodiments, a filling port cover, for example, a filling port cover 2304, may be located in a recess of the filling port valve cap 2604. The filling port cover 2304 may be mechanically coupled or bonded to the recess. In some embodiments, the filling port cover 2304 may be airtightly coupled to the filling port valve cap 2604.

[0204] Figure 27 shows an apparatus 2700 for preparing a binding medium according to one embodiment. In some embodiments, the acoustic binding medium is (i) degassed to reduce the level of dissolved gas in the medium and to allow bubbles to be absorbed into the medium if bubbles are inadvertently introduced during manufacturing, and / or (ii) heated before filling the catheter to reduce the viscosity of the binding medium and speed up the IVUS catheter filling process. The apparatus 2700 may include a container 2702, a vacuum pump 2704, a magnetic stirring hot plate 2706, and a syringe 2708. The container 2702 may be connected to the vacuum pump 2704 via a tubing section and a reversal valve 2710. The container 2702 may be connected to the syringe 2708 via a valve 2712, for example, a stopcock valve. The container 2702 can receive and hold the acoustic binding medium 2714. According to some embodiments, a magnetic stirring bar 2716 may be placed inside the container 2702. According to some embodiments, the magnetic stirring hot plate 2706 may be used to heat and / or stir the acoustically coupled medium 2714 via the magnetic stirring bar 2716. In one embodiment, the apparatus 2700 may also include a vacuum gauge, a sensor for measuring the oxygen content of the medium, and / or a thermal sensor (not shown) for measuring the temperature of the medium to monitor and control the preparation process.

[0205] The apparatus 2700 may be used to prepare an acoustic coupling medium 2714 for filling an IVUS catheter. The process can be initiated by providing a container 2702. In some embodiments, the acoustic coupling medium 2714 comprises one of polyethylene glycol (PEG), PEG with some water, water, saline solution, glycerin, and natural oil. In one embodiment, the acoustic coupling medium 2714 is PEG400. The acoustic coupling medium 2714 may be left to stand for a period of time, for example, 30, 60, 90, or 120 minutes. This period may be long enough to allow the acoustic coupling medium 2714 to reach an air-saturated state. For example, PEG400 can be left to stand in the ambient environment for at least 30, 45, 60, 75, 80, 90, 100, 120, 150, or 180 minutes (and any range and value within that). In one embodiment, the acoustic coupling medium 2714 is left to stand for at least 0.5 to 2 hours. In some embodiments, this period may continue until the acoustically coupled medium 2714 reaches an air saturation threshold. The air saturation threshold can be measured as the deoxygenation rate (DO%). In various embodiments, the DO% may be reduced to 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or more. In one embodiment, magnetic stirring and vacuuming are applied until the DO% is degassed to 80% or more. In one embodiment, measurements of the saturated medium (e.g., 231.0) and the degassed medium (e.g., 33.9) are taken, and the DO% removal rate is approximately 85%. In some embodiments, air saturation of the acoustically coupled medium 2714 can be detected by a sensor, such as a deoxygenation meter probe. The standing period may continue until the deoxygenation meter probe detects that the acoustically coupled medium has reached an air saturation threshold.

[0206] The process may continue, and the container 2702 may be partially or entirely filled with the acoustic coupling medium 2714. The container 2702 may be sealed and arranged to be fluidly connected to the vacuum pump 2704 via the tubing and the directional valve 2710. For example, a rubber stopper with a fluid connector may be placed at the upper opening of the container 2702. The rubber stopper can be connected to the directional valve 2710, which may be arranged to be fluidly connected to the tubing and the vacuum pump 2704.

[0207] The vacuum pump 2704 can be turned on to remove air from the container 2702 and create negative pressure in the medium. In some embodiments, the vacuum pump 2704 can be operated for a degassing period. The degassing period may be 30 minutes, 45 minutes, 60 minutes, 75 minutes, 90 minutes, 105 minutes, 120 minutes, etc. The degassing period may be based on the acoustic coupling medium 2714 and its properties, the volume of the acoustic coupling medium 2714 placed in the container 2702, and / or the size of the container 2702. The degassing period may continue until the acoustic coupling medium 2714 reaches a desaturation threshold. In some embodiments, the desaturation threshold may be the percentage of the air saturation threshold. For example, the desaturation threshold may be 5% or less, 10% or less, 15% or less, 20% or less, 25% or less, 30% or less, 35% or less, 40% or less, 45% or less, or 50% or less of the air saturation threshold. For example, the desaturation threshold may be about 20% of the air saturation threshold.

[0208] In some embodiments, the magnetic stirring hot plate 2706 can heat the acoustically coupled fluid above the degassing temperature. The degassing temperature may be selected based on one or more properties of the acoustically coupled medium 2714. For example, the degassing temperature may be 40 degrees Celsius (°C) for PEG400. In some embodiments, the magnetic stirring hot plate 2706 can stir the acoustically coupled medium 2714 via the magnetic stirring bar 2716.

[0209] In some embodiments, the container 2702 may include a port 2718. The port 2718 may be located at the bottom of the container 2702 and may be used to extract the acoustically coupled medium 2714 from the container. In some embodiments, a valve 2712 may be attached to the port 2718. A syringe 2708 may be attached to the valve 2712. To extract the acoustically coupled medium 2714, the valve 2712, such as a stopcock valve, can be opened, and the syringe 2708 can be used to draw the acoustically coupled medium 2714 from the container 2702. In some embodiments, the valve 2710 may include a thermocouple and / or a monitoring cable. The thermocouple and cable may be embedded in the valve 2710. The thermocouple may be located in the coupled medium 2714, near the bottom of the container 2702. The cable may extend from the thermocouple and valve 2710 and be connected to a monitoring unit. In some embodiments, the monitoring unit may measure the temperature. The thermocouple and its cable may extend through a second valve, such as a stopcock valve similar to the stopcock valve 2712 in some embodiments. A second stopcock valve may be provided in addition to the first stopcock valve 2712. The second stopcock valve can provide an additional method for measuring the temperature of the acoustically coupled medium.

[0210] The vacuum pump 2704 may be stopped. In embodiments involving heating and / or magnetic stirring, the magnetic stirring hot plate 2706 may also be stopped from heating and / or stirring the acoustically coupled medium. The reversal valve 2710 can be opened at an opening speed (which may be slow). The opening speed may allow ambient air to enter the container 2702 without disturbing the medium 2714. The deaerated medium 2714 can be removed from the container 2702 via the syringe 2708. The plunger of the syringe 2708 can be pulled to draw the acoustically coupled medium 2714 out of the container 2702. In some embodiments, the deoxygenation rate of the medium 2714 can be detected. If the deoxygenation rate does not meet the desaturation threshold, the vacuum pump 2704 and / or the magnetic stirring hot plate 2706 can be restarted and the process can be continued until the medium 2714 reaches the desaturation threshold.

[0211] If the medium 2714 satisfies the desaturation threshold, the container 2702 can be repressurized to atmospheric pressure. The acoustically coupled medium 2714 can then be drawn out of the container 2702 using syringe 2708. In some embodiments, syringe 2708 may be one of several syringes. Once the first syringe 2708 is filled, it may be removed from the container 2702 and valve 2712. Another syringe may be attached and used to draw the medium 2714 out of the container 2702. In some embodiments, valve 2712 may be one of several parallel valves. Multiple parallel valves can be used to fill multiple syringes, including syringe 2708, at once.

[0212] In various embodiments, other devices are provided for exposing the binding medium to heat and negative pressure in a controlled manner.

[0213] Figure 28A shows an apparatus 2800 for filling and heating an acoustically coupled medium and / or a catheter during a filling step, according to one embodiment. The apparatus 2800 may include a syringe pump device 2802 and a catheter heating plate 2804. In some embodiments, the apparatus 2800 may also include a microscope 2806. During the filling procedure, an IVUS catheter 2808 may be placed in the catheter heating plate 2804. The catheter heating plate 2804 can heat the IVUS catheter 2808 to a target catheter temperature. The target catheter temperature may be at least 35°C, at least 37°C, at least 40°C, at least 45°C, at least 50°C, at least 55°C, at least 60°C, at least 65°C, at least 70°C, at least 75°C, at least 80°C, etc. In some embodiments, the target catheter temperature may be based on one or more properties of the acoustically coupled medium and / or one or more properties of the IVUS catheter 2808.

[0214] Figure 28B shows a syringe pump device 2802 for heating a bonding medium according to one embodiment. The syringe pump device 2802 may include a syringe pump 2810, a syringe heating component 2812, a pressure gauge 2814, at least one tubing section 2816, a rotary motor 2818, and / or a three-way valve 2820. The syringe pump 2810 may accept one or more syringes, such as syringe 2708, which are filled or partially filled with an acoustic bonding medium. The syringe pump 2810 may have one or more syringe retainers. The syringe retainers may be located on the top or side of the syringe pump 2810. The syringe retainers can releasably secure one or more syringes to the syringe pump 2810. In some embodiments, the syringe retainers may include a rubber U-shaped surface that accepts the body of syringe 2708. The syringe pump 2810 may include an operating surface. The operating surface is driven by the motor of the syringe pump and can apply pressure to the piston of the syringe 2708. The operating surface can discharge the contents of the syringe 2708 at a delivery rate. The delivery rate may be 0.1 mL / min, 0.2 mL / min, 0.3 mL / min, 0.4 mL / min, 0.5 mL / min, 0.6 mL / min, 0.7 mL / min, 0.8 mL / min, 0.9 mL / min, 1.0 mL / min, etc. The delivery rate may be based on one or more properties of the acoustically coupled medium used to fill the IVUS catheter. For example, according to some embodiments, the delivery rate of PEG400 may be 0.4 mL / min.

[0215] The syringe heating component 2812 may be a syringe jacket that fits onto the body of the syringe 2708 and heats the syringe 2708. For example, the syringe heating component 2812 may be wrapped around the body of the syringe 2708. The syringe heating component 2812 may include one or more heating elements. The syringe heating component 2812 can heat the syringe to a target temperature. The target temperature may be based on one or more properties of the acoustic coupling medium. The target temperature may be 35°C, 37°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, etc. For example, in the case of PEG400, the target temperature may be 60°C. In some embodiments, the target temperature may coincide with the catheter target temperature of the catheter heating plate 2804. The syringe heating component 2812 can heat the syringe to a target temperature over a heating period. The heating period may be 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 10 minutes, 15 minutes, 20 minutes, etc. In some embodiments, the syringe heating component 2812 can heat the syringe 2708 before and / or during the filling of the IVUS catheter. In some embodiments, the syringe jacket 2812 may be a component of the syringe pump 2810 according to some embodiments. For example, the syringe pump 2810 may include the syringe heating component 2812 within the syringe retainer.

[0216] The syringe device 2802 may include at least one tubular section 2816. The tubular section 2816 may be connected to the syringe 2708 at its proximal end. In some embodiments, the tubular section 2816 may be connected to the syringe 2708 via an air removal filter. In some embodiments, the tubular section 2816 may be connected to the syringe 2708 via a pressure gauge 2814. According to some embodiments, the pressure gauge 2814 can provide the syringe pump 2810 with the pressure in the tip of the syringe 2708 and / or the tubular section 2816. The syringe pump 2810 can determine the delivery rate of the contents of the syringe 2708 based on the pressure provided by the pressure gauge 2814. The pressure gauge 2814 can be monitored to ensure that the pressure in the syringe device 2802 and / or the IVUS catheter does not exceed a pressure threshold. In some embodiments, the pressure threshold may be 40 psi, 45 psi, 50 psi, 55 psi, 60 psi, 65 psi, 70 psi, 75 psi, 80 psi, 85 psi, 90 psi, 95 psi, 100 psi, 105 psi, 110 psi, 115 psi, 120 psi, etc. For example, according to some embodiments, the pressure threshold for filling an IVUS catheter may be 80 psi. If the pressure in the syringe device 2802 or the IVUS catheter exceeds the pressure threshold, the syringe pump 2810 may stop, and the pressure in the device 2802 may dissipate. In some embodiments, the pressure threshold can be changed if the pressure in the syringe device 2802 exceeds the pressure threshold one or more times, two or more times, three or more times, four or more times, etc. In another embodiment, the pressure gauge can be removed if the filling process is designed to fully fill the catheter without air bubbles.

[0217] At its distal end, the tubing portion 2816 can be connected to the connector hub 2300 of the catheter 2808 to fill the imaging lumen of the catheter. The proximal connector hub may be further mounted to a rotary motor 2818 to rotate the imaging core during filling. For example, the tubing portion 2816 may be attached to the connector hub 2300, and the proximal connector hub may be further mounted to the rotary motor 2818. The distal end of the tubing portion 2816 can be connected to the connector hub 2300 via a three-way valve 2820. According to some embodiments, a filling adapter 2514 can be positioned at the distal end of the tubing portion 2816. For example, the filling adapter 2514 may be mechanically coupled and / or bonded to the distal end of the tubing portion 2816. As described above, the filling adapter 2514 can be mated with the filling port of the connector hub 2300. According to some embodiments, the tubing portion 2816 may be part of the filling nozzle 2504.

[0218] The syringe device 2802 may include a rotary motor 2818. The rotary motor 2818 can rotate the imaging core during the filling procedure. The rotary motor 2818 can operate at a target speed. The target speed can rotate the imaging core to help remove air bubbles during the filling process. Agitating the binding medium 2714 during the filling process can help air bubbles move distally and be discharged. The target speed may be 1000 rpm ± 100 rpm. Other target speeds may be selected depending on the viscosity of the binding medium and the selected medium. The target speed may be 100 rpm to 1500 rpm. For example, the target speed may be 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, or 1500 rpm. In some embodiments, the target speed can be reduced if air bubbles are present in the imaging lumen. For example, this can occur if an air bubble is lodged and is not moving distally toward the distal port of the imaging tube lumen. In some embodiments, the rotation is steady state. In other embodiments, the rotation is pulsating.

[0219] As described above, an acoustic coupling medium, such as PEG400, can be degassed and placed in one or more syringes 2708. During the filling procedure, the catheter heating plate 2804 may be heated to the target catheter temperature. The syringes 2708 may be placed in the holding component of the syringe pump 2810. A syringe heating component 2812, such as a syringe jacket, is wrapped around the syringe 2812 to heat the syringe to a target temperature, for example, 60°C. The tubing 2816 may be connected to the syringe 2708 at a first end or to a filling nozzle at a second end, the filling nozzle being connected to the filling port of the connector hub 2300. The syringe pump 2810 may be operated to discharge the acoustic coupling medium from the syringes 2708 into the tubing 2816. The syringe pump 2810 can discharge the acoustic coupling medium from the syringes 2708 at a target flow rate, for example, 0.4 mL / min. The rotary motor 2818 may be operated to facilitate the movement of the acoustically coupled medium into the IVUS catheter 2808 and / or to assist in the removal of air from the acoustically coupled medium. According to some embodiments, the rotary motor can operate at 1000 rpm ± 100 rpm. A pressure gauge 2814 can monitor the pressure in the tubing section 2816 and / or syringe device to ensure that the pressure does not exceed a pressure threshold, e.g., 80 psi. The process can continue until the imaging lumen of the IVUS catheter 2808 is filled with the acoustically coupled medium. The IVUS catheter 2808 may be sealed as discussed herein and then used in an IVUS imaging procedure.

[0220] Figure 29A shows an isometric view of a catheter heating plate 2804 according to one embodiment. Figure 29B shows a side view of a catheter heating plate 2804 according to one embodiment. As discussed herein, the catheter heating plate 2804 can heat an IVUS catheter 2808 to a target catheter temperature. The catheter heating plate 2804 may include two or more layers. In some embodiments, the catheter heating plate 2804 may include an insulating layer 2902, a heating element 2904, a catheter receiving layer 2906, and a cover layer 2908. The catheter receiving layer 2906 may be made of metal, a metal alloy, or a metal composite. For example, the catheter receiving layer 2906 may be made of aluminum. The catheter receiving layer may include a notch 2910 for receiving an IVUS catheter. The notch may have different shapes, such as an "S" shape as shown in Figure 29A, a "spiral" shape as shown in Figure 28A, or a linear notch. The notch shape may be based on the type of imaging core of the IVUS catheter placed therein. The heating element 2904 may include one or more individual heating elements. For example, the heating element 2904 may be a heater blanket controlled by the controller 2912.

[0221] In one embodiment, the acoustic medium preparation device 2700 and the filling device 2800 are the same device. For example, a chamber 2702 connected to a vacuum source for degassing the medium may also be connected to a pressure source. The pressure or vacuum in the chamber can be controlled by a three-way valve between the pressure source, the vacuum source, and the chamber. Alternatively, the valve is a four-way valve that can also expose the chamber to ambient pressure. In one embodiment of the manufacturing method, the medium is first exposed to vacuum during the degassing step and then exposed to pressure during the catheter filling step. The medium may be heated during the degassing and / or filling steps. Alternatively, the chamber 2702 is connected to a filling syringe as shown in Figure 27, but the valve 2712 is a three-way valve that may be configured in one position to fill the syringe from the chamber 2702 and then in a second position to connect the filled syringe to a filling nozzle.

[0222] In one embodiment, the filling device is connected to a plurality of filling nozzles via a tubular section and / or manifold component so that two or more catheters can be filled at once.

[0223] Figure 30 shows a side view of the distal compartment of an IVUS catheter 3000 having an imaging core 104 housed within a catheter jacket 3206, according to one embodiment. As discussed herein, the imaging core 104 may be located within the imaging lumen of the IVUS catheter 3000. The IVUS catheter 3000 may include a catheter jacket 3206, as discussed herein. In some embodiments, the imaging core 104 may include a transducer 105 cabled within a transducer housing 3008. The transducer housing 3008 may include an opening that allows ultrasound signals to be transmitted and received by the transducer 105. For example, as shown in Figure 30, the transducer housing 3008 includes an opening above the transducer 105. The transducer housing 3008 may include one or more housing apertures 3009. In one embodiment, the aperture 3009 is an opening that extends through the inside of the transducer housing 3008. In various embodiments, one or more apertures 3009 may be (i) located at the proximal end of the coil 3004, and / or (ii) along the outer surface of the transducer housing 3008 (e.g., longitudinally, circumferentially, or in part thereof), with each aperture 3009 forming a fluid / air connection to the inside of the coil 3004. One or more apertures 3009 may allow the bounding medium to fill the inside of the coil 3004 more efficiently during the medium filling process (e.g., compared to the absence of apertures 3009). This helps to reduce or eliminate air bubbles in the catheter 3000. In one embodiment, one or more apertures 3009 may extend longitudinally, such as along the outer surface of the transducer housing 3008, allowing fluid / air to move distally within the coil 3004 and out of the housing during the medium filling process. Figure 30A shows an exemplary cross-sectional view of the proximal section of the transducer housing 3008, which shows an aperture 3009 connecting the inside of the coil 3004 to the upper open surface of the transducer 105.The cable-connected transducer 105 and transducer housing 3008 may be coupled to a drive shaft containing a coil 3004 by a coupling 3010. In some embodiments, the coupling 3010 supports a secure mechanical connection between the transducer housing 3008 and the coil 3004. This coupling may be joined to juxtaposed components by laser welding or adhesive. The coupling 3010 may include one or more apertures 3009.

[0224] Figure 31 shows a side view of the proximal hub 3102 of an IVUS catheter 3100 according to one embodiment. As discussed herein, the IVUS catheter 3100 may include a proximal drive shaft, for example, a hypotube 3104. The drive shaft 3104 may include one or more apertures 3106. One or more apertures 3106 may allow an acoustic coupling medium to enter the drive shaft and move more easily through the coil 3004. One or more apertures 3106 may allow air to exit the imaging core from within the coil 3004.

[0225] Figure 32 shows a cross-section of the IVUS catheter 3200. As discussed herein, the IVUS catheter 3200 may include an imaging core 104 and a catheter jacket 3206. The imaging core 104 may include a coil 3204 and an electrical coaxial cable 3202, both of which, according to some embodiments, are located within the inner imaging lumen 108 of the IVUS catheter 3200, formed by the catheter jacket 3206. As shown in Figure 32, there may be a first gap 3208 between the coaxial cable 3202 and the coil 3204, and a second gap 3210 between the coil 3204 and the catheter jacket 3206. In some embodiments, the cross-sectional area of ​​the first gap 3208 may be much smaller than the cross-sectional area of ​​the second gap 3210.

[0226] In some embodiments, the coil 3204 may have an inner diameter of approximately 0.005 inches to 0.030 inches (e.g., 0.005, 0.008, 0.010, 0.012, 0.015, 0.018, 0.020, 0.022, 0.024, 0.027, 0.030 inches and overlapping values ​​and ranges therein) and an outer diameter of approximately 0.015 inches to 0.045 inches (e.g., 0.015, 0.018, 0.020, 0.023, 0.025, 0.028, 0.030, 0.032, 0.035, 0.038, 0.040, 0.042, 0.045 inches and overlapping values ​​and ranges therein). In some embodiments, the jacket 3206 may have an inner diameter of 0.020 inches to 0.050 inches (e.g., 0.020, 0.023, 0.025, 0.028, 0.030, 0.033, 0.035, 0.038, 0.040, 0.042, 0.045, 0.048, 0.050 inches and overlapping values ​​and ranges therein). In some embodiments, the coaxial cable 3202 may have an outer diameter of 0.002 inches to 0.025 inches (e.g., 0.002, 0.005, 0.008, 0.010, 0.012, 0.014, 0.018, 0.020, 0.022, 0.025 inches and overlapping values ​​and ranges therein). In some embodiments, the area outside coil 3204 is 1.5 to 3.0 times larger (e.g., 1.5, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0) times larger than the area between coaxial cable 3202 and coil 3204. Smaller areas can create greater resistance to medium filling than larger areas. Other inner and outer diameters may be used depending on the selected dimensions of the IVUS catheter 3200, and the difference between the two areas may vary. In some embodiments, the apertures shown in Figures 30, 30A, and 31 reduce resistance to the medium flow for removing air inside coil 3204 compared to the medium flow outside coil 3204, improving the speed and efficiency of the filling process and / or effectively removing air during the filling process.

[0227] Figure 33 shows the flow of acoustic coupling medium through the imaging lumen of the IVUS catheter 3300 during the filling process in several embodiments. The acoustic coupling medium may flow through the apertures of the drive shaft 3104, the coupling 3010, and / or the transducer housing 3008. Advantageously, one or more apertures 3106 may allow air to escape from the coil 3004 of the imaging core, the drive shaft, and / or other internal components of the IVUS catheter 3300 while maintaining the structural integrity and functionality of the device. Generally, IVUS catheters may have a small diameter to fit into human blood vessels. This allows the diameter of the rotating imaging core to be optionally smaller to fit inside the outer catheter polymer jacket. These components may occupy most of the available space inside the catheter lumen, leaving a very small space containing air, which may need to be effectively replaced with coupling medium by an effective filling process. Poorly designed geometric features of the components can hinder air removal; therefore, in some embodiments, it is the object of this application to support the flow of the bonding medium through the lumen, thereby pushing out and / or drawing in air. Acoustic bonding media may have high viscosity, which presents an even greater challenge during the filling process. For example, the viscosity of the acoustic bonding media can significantly slow down the filling process. Therefore, an object of this application is to provide component designs that support a more efficient and cost-effective filling method in some embodiments.

[0228] Figure 34 shows a process 3400 for degassing an acoustically coupled medium and filling an IVUS catheter, according to one embodiment. Process 3400 can be initiated in step 3402, in which a degassing device, such as apparatus 2700, is provided. The degassing device may include one or more components of apparatus 2700. Process 3400 may proceed to 3404, in which the acoustically coupled medium is held in the ambient environment for a first period. The acoustically coupled medium may be placed in a container of the degassing device, for example, container 2702. The acoustically coupled medium may be held in the ambient environment until the acoustically coupled medium reaches an air saturation state, as described above in relation to Figure 27. The first period may be 30 minutes, 60 minutes, 90 minutes, 120 minutes, etc. The first period may continue until the acoustically coupled medium reaches an air saturation threshold.

[0229] Process 3400 may proceed to step 3406, where the acoustic coupling medium may be held under vacuum pressure for a second period. As described above, the acoustic coupling medium may be placed in a vessel 2702, and the vacuum pump 2704 may be turned on to remove gas from the vessel 2702 for at least part of the second period. The second period may be 30 minutes, 45 minutes, 60 minutes, 75 minutes, 90 minutes, 105 minutes, 120 minutes, etc. The second period may be based on the acoustic coupling medium and its properties, the volume of the acoustic coupling medium placed in the vessel 2702, and / or the size of the vessel 2702. During the second period, the magnetic stirring hot plate may heat and / or stir the acoustic coupling medium.

[0230] Process 3400 may proceed to determination step 3408, where it is determined whether the acoustic coupling medium satisfies the desaturation threshold. In some embodiments, the desaturation threshold may be the air saturation threshold rate. For example, the desaturation threshold may be 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, or 50% of the air saturation threshold. For example, the desaturation threshold may be about 20% of the air saturation threshold. If the desaturation threshold is not met, the process may return to step 3406, where the acoustic coupling medium may be held at vacuum pressure until the desaturation threshold is met.

[0231] If the desaturation threshold is met, the process proceeds to step 3410, where the acoustically coupled medium is transferred to a syringe, for example, syringe 2708. As described above, the container 2702 may include a valve 2712. Syringe 2708 may be attached to the valve 2712 and may draw the acoustically coupled medium from the container 2702 as described above in relation to Figure 27. In some embodiments, the acoustically coupled medium may be transferred to multiple syringes.

[0232] Process 3400 can proceed to step 3412, where the IVUS catheter 2808 is heated to a target temperature. In some embodiments, the IVUS catheter 2808 can be heated to a target temperature by a catheter heating plate, for example, catheter heating plate 2804. The target temperature may be at least 35°C, at least 37°C, at least 40°C, at least 45°C, at least 50°C, at least 55°C, at least 60°C, at least 65°C, at least 70°C, at least 75°C, at least 80°C, etc. In some embodiments, the catheter target temperature may be based on one or more properties of the acoustic coupling medium and / or one or more properties of the IVUS catheter 2808.

[0233] According to some embodiments, process 3400 can proceed to step 3414, where the IVUS catheter 2808 can be filled. As described above, the IVUS catheter 2808 may include a proximal connector hub, for example, a proximal connector hub 300 or 2300. The proximal connector hub may include a filling port, for example, a filling port 2324. The IVUS catheter 2808 may also be filled by placing a syringe filled with acoustically coupled medium into a syringe pump device, for example, a syringe pump device 2802. The syringe pump device 2802 is activated as described above and can be used to fill the IVUS catheter 2808 via the filling port 2324, as described in relation to Figures 23A-23B, 24A, 26A-26D, 28A and 28B. The syringe device 2802 may include a syringe pump 2810 capable of discharging the acoustically coupled medium from the syringe 2708 at a target flow rate, for example, 0.4 mL / min. The syringe device 2802 may include a rotary motor 2818 for rotating the imaging core during filling. The target speed may be 1000 rpm ± 100 rpm. The filling process can continue until the imaging lumen of the IVUS catheter 2808 is filled with the acoustic coupling medium. In some embodiments, as described above, the rotary motor 2818 can be used to agitate the IVUS catheter 2808 to remove air from the acoustic coupling medium.

[0234] Process 3400 can be terminated in step 3416, in which the IVUS catheter 2808 is sealed. As described above, the distal end of the catheter may be sealed with the distal plug 406. The proximal end of the catheter may be sealed at the proximal connector hub, for example, via the mechanism described above in relation to Figures 25A-25B and 26A-26D.

[0235] Process 3400 may include more or fewer steps according to some embodiments. The steps of process 3400 may be performed in a different order or simultaneously with one or more of the other steps of the process.

[0236] Endoscopic and other non-vascular imaging can incorporate some of the features described herein. Transvaginal and other gynecological ultrasound devices can, for example, include some of the features described herein. While the figures above may refer to an IVUS catheter, in embodiments where endoscopic ultrasound and other intraluminal imaging (or imaging of other body cavities or organs) are performed (and such imaging is not intravascular), the features described herein for “IVUS” or “catheter” apply to intraluminal (including EUS, cavity, organ, etc.) catheters, probes, tubular sections, scopes, etc.

[0237] Several embodiments of medical imaging systems, such as IVUS systems, are provided herein. Advantageously, according to some embodiments, such systems include one or more improvements over conventional IVUS systems, such as enhanced imaging, image-guided therapy, improved usability, easier setup, streamlined clinical workflow, reduced operating time, improved clinical effectiveness, improved accuracy of diagnostic images, improved accuracy of therapeutic intervention delivery, improved guided intervention therapy, more efficient peripheral intervention, faster information-based treatment decisions, and faster measurement and reporting. In some embodiments, IVUS is a diagnostic image-guided therapy tool for the treatment of both peripheral arterial and venous diseases, enabling 2D and / or 3D intraluminal visualization.

[0238] For example, image interpretation and measurement of lumen shape using a flushless catheter (e.g., diameter, stenosis, peripheral intervention, coronary artery intervention, atherosclerosis, lithotripsy, endovascular lithotripsy (IVL), balloon placement, stent placement, venous procedures, subknee joint (BTK) procedures, arteriovenous fistula, and other procedures) are performed in embodiments described herein. Procedures may be performed by interventional cardiologists, radiologists, and / or vascular surgeons in hospitals, clinics, office-based laboratories (OBLs), and / or outpatient surgical centers (ASCs). Several implementations In this context, the systems described herein can be used efficiently in hospitals and OBL / ASC without specialized clinical support. Interventions may include therapies or other interventions such as peripheral interventions, coronary interventions, atherosclerosis, IVL, balloon placement, stent placement, venous procedures, BTK procedures, arteriovenous fistulas, and other procedures. Imaging may include, for example, IVUS non-coronary peripheral vessels, intra-coronary IVUS, ultrasound, intraluminal imaging, imaging of body cavities and organs, and other imaging (and combinations thereof) described herein.

[0239] Many of these embodiments should be particularly advantageous in ensuring that patients do not receive unnecessary additional diagnoses or interventions, thereby providing better patient care and reducing the short-term burden on the healthcare system. Similarly, many of these embodiments should help patients receive the necessary additional diagnoses or interventions they need, thereby providing better patient outcomes (by treating patients earlier in the disease progression timeline) and reducing the long-term burden on the healthcare system. In some embodiments, IVUS systems with flushless catheters offer a modern IVUS platform and catheter product range that provides improved usability with superior image interpretation and streamlined bedside workflows at a competitive cost, enabling broader adoption.

[0240] In some embodiments, one or more of the following features are provided.

[0241] Plug-and-Play Catheters: According to several embodiments, flushless catheters are optimized for angiography and configured for excellent pushability, traceability, and transverseness for arterial and venous vascular systems. In some embodiments, the catheter has excellent pushability that can avoid kinking and sufficient column strength to pass through tortuous bends and occlusions in vessels without buckling, excessive bending, or crushing in any part of the catheter (e.g., the ability to transverse occlusions or stenoses). In some embodiments, the catheter has excellent traceability with respect to the ability of the catheter to follow a guidewire through tortuous bends in the vascular system and has sufficient flexibility and strength to move along the guidewire and advance along the guidewire to a target location in the vascular system. In some embodiments, the catheter has excellent transverse capability to transverse occlusions, restrictions, and stenoses in the vascular system, such as sites with tissue occlusion (e.g., stenosis, etc.) and / or implant occlusion (e.g., stents, balloons, etc.). Systems described herein, such as IVUS catheters, may include a plug-and-play rotating design, which may allow, for example, the catheter to be removed from the sterile package and prepared for use without the need to flush the device. In one embodiment, the catheter has a single rotating ultrasonic element. In some embodiments, the catheter includes an enclosed binding medium (e.g., binding medium, medium, liquid, fluid, gel, etc.) that supports the rotating imaging core inside the catheter jacket. In one embodiment, the IVUS catheter is a plug-and-play catheter with a 280 cm total length rotating IVUS design flashless peripheral disposable imaging catheter with a 150 cm working length that fits a 0.014 inch guidewire and a 5F sheath, allowing the IVUS catheter proximal connector to be attached to a CIM outside the sterile field. In one embodiment, the IVUS catheter is a plug-and-play catheter with a 250 cm total length flashless peripheral disposable imaging catheter with a 110 cm working length that fits a 0.035 inch guidewire and an 8F sheath, allowing the IVUS catheter proximal connector to be attached to a CIM outside the sterile field.Connecting outside the sterile field optionally avoids the need to drape a motor unit with cables connected inside the sterile field. In some embodiments, high-definition (e.g., HD, ultra-high-definition (UHD), UHD+, etc.) imaging uses acoustic pulse echoes with matched excitation frequency spectra for optimal penetration, ultra-high resolution, and high-definition image quality. In some embodiments, the system is optimized for peripheral vascular imaging, coronary artery imaging, or both. In one embodiment, the imaging core rotates inside a polymer jacket using an internal drive shaft connected via a proximal hub / connector. The hub connector is optionally attached to the CIM after removal from the sterile catheter package. A transducer located at the distal tip of the imaging core can rotate at 1500–4000 rpm and receives echoes for processing into a circular image on a tablet display. The catheter length can be 8 to 10 feet. In various embodiments, the catheter can be removed from the sterile package and prepared for use without the need to flush the device. The length may allow the catheter proximal connector to connect to the CIM outside the sterile field. In one embodiment, connecting outside the sterile field avoids the need to drape a motor unit with cables connected inside the sterile field. The catheter may include non-volatile memory containing unique catheter identification, usage data, and calibration for optimal imaging performance. According to some embodiments, the calibration may include data relating to electrical impedance versus frequency measurements, data relating to acoustic sensitivity versus frequency measurements, and / or beam profile data specific to individual devices.

[0242] A catheter interface module (CIM) is, in several embodiments, a hardware interface between a system cable from a workstation and a disposable catheter. In some embodiments, the CIM provides rotational drive and ultrasound signal processing functions to the system (e.g., an IVUS system). Custom electronics can control a motor that rotates the imaging core within the catheter. The electronics can also transmit and receive ultrasound signals between a rotational transducer in the distal end of the catheter tip and a custom printed circuit board in the workstation. In various embodiments, the CIM provides an interface for reading and writing non-volatile memory within the catheter, for example. The memory can be used to calibrate the ultrasound transducer of each unique catheter. In one embodiment, the catheter memory can be used to select an appropriate system configuration to achieve the best possible imaging performance. The CIM can transmit ultrasound signals, sensor data, and / or catheter information from the catheter to the workstation and / or at least one user interface device (e.g., a tablet, computer, etc.), and the user interface device can store the transmitted information in non-volatile memory in one or more locations. In one embodiment, the CIM is mounted on a bed rail outside the sterile field. In some embodiments, the CIM is embedded in or integrated with imaging control equipment, workstations, housings, tables, beds, pedestals, platforms, and / or carts. In some embodiments, the CIM is located outside the sterile field. In some embodiments, one or more ports are provided to enable seamless connectivity between the IVUS system and other imaging modalities.

[0243] Image Co-registration: In some embodiments, the IVUS system provides co-registration data to offer one-to-one positional identification, enabling therapeutic accuracy. Advantageously, some embodiments described herein can function in cooperation with or independently of co-registration with another imaging modality, such as fluoroscopy, where a software algorithm tracks radiopaque (RO) catheter markers or RO transducers through continuous fluoroscopy recordings. Co-registration with angiography can be used for determining the 3D shape of lesions, including the length of vessels, lumens, and lesions, efficient stent selection, and efficient determination of stent implantation sites, all aimed at reducing procedure time, decreasing contrast agent usage, and improving physician proficiency in IVUS operation. Described herein are some embodiments that achieve one or more of these advantages with or without co-registration.

[0244] Synergistic effects of vascular intervention: In some embodiments, the IVUS system is configured for optimized vascular procedures. Some systems and methods described herein can be used for peripheral, coronary, and other intravascular applications. Other embodiments are used for non-vascular luminal applications such as endoscopy.

[0245] For example, an endoscope may be used in conjunction with some of the features described herein. Transvaginal and other gynecological ultrasound devices may also include some of the features described herein. In embodiments in which EUS (endoscopic ultrasound) and other intraluminal imaging or imaging of other body cavities or organs is performed (and such imaging is not intravascular), the features described herein for “IVUS” or “catheter” should be understood to apply to intraluminal (or other cavity / organ) catheters, probes, tubular sections, scopes and other such devices.

[0246] In some embodiments, the systems and methods are configured and optimized for peripheral vascular procedures (and not for coronary vascular procedures). In one embodiment, systems and methods configured, designed or adapted for or solely for the peripheral vascular system include one or more of the following features: flexibility, maneuverability, length, diameter, material, and / or flexural strength, to improve intrusion, traceability, and transversability within the lumen (e.g., the ability to traverse obstacles or stenoses). Some of these features may also be incorporated into applications other than peripheral IVUS. In some embodiments, the system is configured to image and / or measure tissue before a treatment procedure, for example, to identify and plan the treatment procedure. In some embodiments, the system is configured to image and / or measure tissue after a treatment procedure, for example, to confirm the outcome and results of the treatment procedure. In some embodiments, the system is configured to image and / or measure tissue during a treatment procedure.

[0247] Artificial Intelligence: In some embodiments, the systems described herein, including, for example, an advanced intravascular ultrasound platform, leverage AI to enable image interpretation, enhance overall system functionality, streamline workflows, and maximize clinical value. In some embodiments, advantageously, physicians do not need to spatially and temporally integrate (e.g., cognitively integrate) imaging data to fully interpret the clinical state. Instead, the systems according to some embodiments described herein can leverage the power of AI with generational advancements to go beyond a single image interpretation. In some embodiments, the AI-driven engine may include a workstation that enhances image interpretation in a simplified workflow that improves overall usability, for example. In some embodiments, machine learning is used. In one embodiment, the AI-enabled processing power is designed to support real-time and on-demand image interpretation. The AI-driven workstation may provide a high-end processing and AI engine for advanced signal and image processing. In various embodiments, native image data capture provides superior image interpretation (e.g., identification and measurement of boundary detection, vessel size, vascular disease, dissection, plaque morphology, etc.). In some embodiments, the systems described herein provide simplified measurements through automated boundary detection (e.g., an AI algorithm automatically identifies boundaries such as lumens, blood vessels, tissues, lesions, and plaques). In some embodiments, the systems provide simplified measurements through semi-automatic boundary detection (e.g., the user can manually adjust or modify an automated AI algorithm that identifies boundaries such as lumens, blood vessels, tissues, lesions, and plaques, and the boundary selection is reconfigured based on the user's modifications). In one embodiment, AI plaque identification utilizes an AI algorithm to automatically classify and identify the type of plaque within the imaging area and provides user guidance regarding treatment options (e.g., color coding, icons, or text overlays can be used to indicate what types of conditions, such as plaques, may be present in the selected image).In some embodiments, the data-driven platform is designed to collect data and simplify image interpretation using AI processing capabilities that reduce the cognitive load on the user, supporting real-time and on-demand image interpretation to help (i) identify lumen size, (ii) visualize dissection, (iii) characterize disease morphology, (iv) identify and quantify stenosis location, and / or (v) identify true lumen. In some embodiments, image interpretation is used to identify thrombi, thrombosis, blood clots, embolism, plaque, calcium, tissue health, stent or balloon adhesion, and / or the "health" or condition of the stent or balloon. Image interpretation may include imaging to assess the quality and / or location of existing stent placement. Image interpretation may include identifying location relative to the lumen wall, and determining the level and / or quality of tissue grown in and around the stent or balloon. In one embodiment, using, for example, a bioabsorbable stent, image interpretation may include (i) evaluating the amount of stent dissolution, and (ii) determining whether the stent dissolution follows an expected collapse pattern (e.g., determining whether the level of collapse on one side of the stent is similar to that on the other side, and if not, whether the stent is dissolving faster than expected, which may indicate a problem associated with the stent placement or that the stent will not provide the expected structural support to the tissue). In one embodiment, high-fidelity ultrasound data is used to advance improved image generation and image interpretation with options for leveraging artificial intelligence and / or machine learning. In various embodiments, catheters, devices, systems, and methods may be configured to use artificial intelligence algorithms to perform edge-based machine learning computations related to image or image analysis in order to identify tissue boundaries, plaque, calcium, thrombi, dissections, and / or stent adhesions.In some embodiments, data, algorithms, AI, and / or ML are used to acquire data from one or more sensors and provide feedback on the operating mode (such as imaging parameters) via a feedback loop (e.g., closed feedback loop / automation) or user-instructed adjustment. In some embodiments, data, algorithms, AI, and / or ML are used to acquire data from one or more images and provide feedback on the operating mode (such as imaging parameters and / or treatment) via a feedback loop (e.g., closed feedback loop / automation) or user-instructed adjustment.

[0248] In some embodiments, the imaging described herein is used to diagnose whether a patient is suitable for a particular intervention or further diagnosis. In various embodiments, 2D and / or 3D intraluminal visualization is possible. In one embodiment, 2D imaging includes an image in a single plane. In some embodiments, 3D imaging includes a volumetric representation of tissue or lumen. In some embodiments, 3D imaging is reconstructed via an algorithm that interpolates a series of 2D images across a third dimension, takes a series of individual 2D images, estimates linear progression along the third dimension, and uses artificial intelligence (AI) to generate a 3D volumetric representation of the interpolated 2D images. In some embodiments, 3D model generation may include acquiring 2D cross-sectional images of a vascular object so that its position along a vein or artery (e.g., insertion length) can be recorded by an encoder or other sensor. A 3D model of the vascular object can be constructed by drawing each 2D cross-section in 3D with the insertion length for which the cross-section was recorded. In one embodiment, by adding an electromagnetic sensor to the catheter tip, the position of the catheter tip can be recorded when a 2D image is acquired, and thus a 3D model of the vascular structure can be created. In one embodiment, one or more algorithms convert a series of IVUS 2D images and signal data into a volumetric 3D visualization. In one embodiment, the 3D visualization is generated by interpolation of linear and / or nonlinear vascular structure geometric shapes and acoustic reflections from tissue. In one embodiment, pixel-based interpolation is used to visualize the anatomical structure of blood vessels in three dimensions. In some embodiments, a series of cross-sectional 2D IVUS images and / or signals are generated via pixel-based cross-sectional images of blood vessels showing acoustic reflection information along the length of the lumen. In one embodiment, the 3D visualization is generated via algorithms for creating anatomical contour boundaries through smooth 3D surface rendering. In some embodiments, AI is used to create 3D visualization data and images.

[0249] In some embodiments, coronary artery systems and methods are provided. In some embodiments, the device (such as a coronary IVUS catheter) utilizes a smaller diameter, higher rigidity, and characteristics of pushability, traceability, and / or transversality specific to modified coronary arteries. Catheters for coronary artery applications can apply different ultrasound frequencies to account for variations in tissue lumen size; for example, since peripheral vascular systems can have larger vessel diameters, lower frequencies can be used for ultrasound imaging to image at greater distances from the IVUS catheter transducer. In some embodiments, since coronary vessels have smaller diameters, an imaging ultrasound frequency of about 60 MHz can be used, while peripheral imaging can use lower frequencies such as about 40 MHz or less. In some embodiments, the coronary IVUS catheter has lower column strength required for pushability or transversality due to the presence of a guide catheter.

[0250] In some embodiments, catheters optimized for angiography are configured for superior pushability, traceability, and transverseness for the peripheral arterial and venous vascular systems. In some embodiments, one or more of the following features are provided:

[0251] Pushability: In some embodiments, the catheter has excellent pushability that avoids bending and sufficient column strength to pass through tortuous bends and occlusions in the blood vessel without buckling, excessive bending, or crushing in any part of the catheter (e.g., adjacent portion or (e.g., ability to traverse occlusion or stenosis)). Material properties in some embodiments (e.g., balance of stiffness and flexibility, durometer of various segments), dimensional properties (e.g., larger dimensions such as diameter and thickness) increase column strength and improve pushability and bending resistance.

[0252] Traceability: In some embodiments, the catheter exhibits excellent traceability in terms of its ability to follow the guidewire through meandering bends in the vascular system, and possesses sufficient flexibility and strength to move along the guidewire and advance along the guidewire to a target location within the vascular system. Hydrophilic coatings in some embodiments help reduce friction with the surrounding luminal tissue.

[0253] Transverseness: In some embodiments, the catheter has excellent transverseness to traverse occlusions, restrictions, and stenosis within the vascular system, such as sites with tissue occlusion (e.g., stenosis) and / or implant occlusion (e.g., stents, balloons, etc.). According to some embodiments, transverseness is enhanced by one or more of the following: (i) distal tip design (e.g., sharp enough to navigate occlusions, etc., and blunted to avoid snagging on occlusions), (ii) material properties (e.g., balance of rigidity and flexibility, durometer of various segments, etc.), and / or (iii) dimensional properties (e.g., larger dimensions such as diameter and thickness increase column strength). In one embodiment, low durometer near the distal tip is provided for flexibility to navigate tortuous anatomical structures and occlusions. In one embodiment, a region is provided in which the durometer changes gradually in a manner sufficiently proximal to push the catheter while avoiding bending. A single durometer and / or flexibility may be kept constant along specific or all parts of the device.

[0254] The technologies described herein include, in some embodiments, technologies for focusing intraluminal images by rotating a single-element ultrasonic transducer through image modification (e.g., angular diffraction, phase, amplitude, time shift, and synthesis of backscattered reflection images), including technologies described in U.S. Patent No. 63 / 497,962 (and a PCT application claiming priority thereto, filed April 11, 2024), technologies for manually assisted pullback for spatial alignment measurements, voice control, position sensors (e.g., encoders), including technologies described in U.S. Patent No. 63 / 531,266, titled "Systems and Methods for Intravascular Ultrasound Imaging," and technologies described in "Systems and Methods for Intravascular Ultrasound Imaging." This is used in conjunction with an ultrasonic imaging system and its components, voice control, and artificial intelligence algorithms, including the technology described in U.S. Patent No. 63 / 546,058, entitled "Ultrasound," all of which are incorporated in their entirety by reference in this disclosure. [Examples]

[0255] The following embodiments are non-limiting embodiments. [Examples]

[0256] Method for filling an IVUS catheter with an acoustic coupling medium. In the experiment, a method of filling an IVUS catheter with acoustic coupling medium using PEG400 as the acoustic coupling medium was implemented to fill the internal imaging lumen / cavity of the catheter prototype. The prototype "014 catheter" was configured for peripheral vascular imaging using a 0.014-inch OD guidewire. The prototype had an internal rotating core consisting of a coaxial, double-layer torque coil drive cable and a block at the end of the drive cable with a simulated acoustic transducer sized for high-quality imaging. The catheter jacket matched the dimensions of commercially available IVUS catheters. The total length of the catheter was longer than existing commercially available IVUS catheters, at 280 cm for the 014 catheter. Since longer lumen lengths make filling more difficult, the length of the lumen with the sealed coupling medium was significantly longer than that of commercially available catheters, which are intentionally designed to challenge the sealing method. The catheter prototype was successfully filled with PEG400, and all air bubbles were removed from the internal imaging lumen. In other embodiments, alternatives to PEG400, such as other low molecular weight grades of polyethylene glycol and other materials, can also be used. [Examples]

[0257] Method for filling an IVUS catheter with an acoustic coupling medium. In another experiment, PEG400 was used as an acoustic coupling medium to fill the internal imaging lumen / cavity of a catheter prototype. The prototype "035 catheter" was configured for peripheral vascular imaging using a 0.035-inch OD guidewire. The prototype had an internal rotating core consisting of a coaxial, double-layer torque coil drive cable and a block at the end of the drive cable attached to a simulated acoustic transducer with dimensions suitable for high-quality imaging. The catheter jacket matched the dimensions of commercially available IVUS catheters. The total length of the catheter was longer than existing commercially available IVUS catheters, at 250 cm for the 035 catheter. Since longer lumen lengths make filling more difficult, the length of the lumen with the sealed coupling medium was significantly longer than that of commercially available catheters, which are intentionally designed to challenge the sealing method. The catheter prototype was successfully filled with PEG400, and all air bubbles were removed from the internal imaging lumen. In other embodiments, alternatives to PEG400, such as other low molecular weight grades of polyethylene glycol and other materials, can also be used.

[0258] Modifications and alterations to the embodiments described herein can be carried out without departing from the principles of the Disclosure. Each of the aspects and examples disclosed herein may be considered individually or in combination with other aspects, examples, and variations of the Disclosure. Furthermore, unless otherwise specified, none of the steps of the methods disclosed herein are limited to any particular order of execution.

[0259] The methods and apparatus described herein may be subject to various modifications and alternative forms, specific examples of which are shown in the drawings and described in detail herein. Embodiments are not limited to any particular form or method disclosed herein, but rather are intended to encompass modifications, equivalents, and alternatives that fall within the spirit and scope of the various examples and embodiments described herein and / or in the appended claims. Furthermore, any particular features, aspects, methods, characteristics, properties, qualities, attributes, elements, etc., disclosed herein relating to one example may be used in all other examples described herein. The methods disclosed herein do not have to be performed in the order listed. Unless otherwise specified or understood in the context in which they are used, the use of sequential or chronological language such as “then,” “next,” “after,” and “subsequently” is generally intended to facilitate the flow of text and not to limit the order in which the actions performed are performed. Thus, some examples may be performed using a set of actions described herein, while others may be performed according to a different set of actions.

[0260] In particular, conditional language used in this specification such as "can", "might", "may", "e.g.," generally, unless otherwise specified or understood in another sense within the context in which it is used, is intended to convey that some examples include certain features, elements, and / or conditions, while other examples do not. Thus, such conditional language is generally not intended to mean that a feature, element, block, and / or condition is required in any way in one or more examples, or that one or more examples necessarily include logic for determining whether these features, elements, and / or conditions are included in or to be performed in any particular example, regardless of author input or prompt. When an apparatus or method "comprises" or "includes" (the two are interchangeable) a particular feature or step, such an apparatus or method can also "consist essentially of" such a feature or step when so identified in the claims. When an apparatus or method "comprises" or "includes" (the two are interchangeable) a particular feature or step, such an apparatus or method can also "consist of" such a feature or step when so identified in the claims.

[0261] The methods disclosed herein may include specific actions taken by an operator, but the methods can also explicitly or implicitly include user or third-party instructions regarding these actions. For example, an action such as "positioning the device" includes "instructing the positioning of the device".

[0262] The scope disclosed herein also includes any and all overlaps, sub-scopes, and combinations thereof. Words such as “up to,” “at least,” “greater than,” “less than,” and “between” include the numbers listed. Numbers preceded by terms such as “about” or “approximately” include the numbers listed and should be interpreted in context (e.g., as accurately as reasonably possible under those circumstances, e.g., ±5%, ±10%, ±15%). For example, “about 4 inches” includes “4 inches.” Phrases preceded by terms such as “substantially” include the phrases listed and should be interpreted in context (e.g., as accurately as reasonably possible under those circumstances). For example, “approximately straight” includes “straight.” Unless otherwise specified, all measurements are taken under standard conditions, including temperature and pressure. The phrase "at least one" is intended to mean that you need at least one item from the subsequent list, not just one kind of each item from the subsequent list. For example, "at least one of A, B, and C" could be A, B, C, A and B, A and C, B and C, or A, B, and C.

Claims

1. A flashless intravascular ultrasound (IVUS) catheter, An imaging core including a rotating ultrasonic transducer connected to a drive shaft, wherein the drive shaft includes a coil, A flexible, elongated member having a sealed inner lumen, wherein the sealed inner lumen is an imaging lumen. The sealed lumen is configured to receive the imaging core having the rotating ultrasonic transducer and acoustic coupling medium, The sealed lumen includes a proximal end, a distal end, and a flexible wall extending to the length between the proximal and distal ends. A flexible, elongated member, A rigid connector hub comprising an internal chamber, an acoustic coupling medium-filled port, a distal interface, a proximal interface, and a flexible seal, The acoustic coupling medium filling port is configured to insert the acoustic coupling medium into the rigid connector hub to fill the sealed inner lumen. The distal interface is configured to connect to the proximal end of the sealed inner lumen, The proximal end of the sealed inner lumen is configured to be attached to the rigid connector hub, The proximal interface is configured for connection to the catheter interface module. The catheter interface module is equipped with a motor and is configured for electrical connection to the console. The console is configured for controlling the rotational operation of the drive shaft, The flexible seal is distally connected to the seal housing connected to the proximal interface, The flexible seal is connected to the internal chamber of the rigid connector hub in a proximity, The drive shaft extends distally through the flexible seal, Rigid connector hub and Equipped with, The sealed inner lumen is configured to communicate with the flexible seal and the internal chamber via a sealed acoustic coupling medium. Flashless intravascular ultrasound (IVUS) catheter.

2. The flashless IVUS catheter according to claim 1, wherein the seal housing is joined to the rigid connector hub.

3. The flashless IVUS catheter according to claim 1, wherein the seal housing is joined to the rigid connector hub via a seal port.

4. The flushless IVUS catheter according to claim 1, further comprising a second seal housing, the second seal housing being attached to the proximal interface.

5. The flushless IVUS catheter according to claim 1, wherein the proximal end of the sealed inner lumen is provided with a proximal connector strain relief configured to connect to the rigid connector hub.

6. The flushless IVUS catheter according to any one of claims 1 to 5, wherein the drive shaft is rotatably actuated by an actuator located adjacent to the proximal interface.

7. The flushless IVUS catheter according to any one of claims 1 to 5, wherein the acoustic coupling medium-filled port is configured to be sealed after delivery of the acoustic coupling medium.

8. The flushless IVUS catheter according to any one of claims 1 to 5, wherein the distal end of the sealed inner lumen is provided with a distal port.

9. The flushless IVUS catheter according to claim 8, wherein the distal port is sealed after the acoustic coupling medium filling process, and the distal port is configured as an exit port that allows the acoustic coupling medium and air bubbles to exit from the sealed inner lumen.

10. The flushless IVUS catheter according to claim 8, wherein the distal port is sealed by heating.

11. The flushless IVUS catheter according to claim 8, wherein the distal port is sealed via an adhesive.

12. A flashless IVUS catheter according to any one of claims 1 to 5, for use in combination with at least one of an X-ray device and an external ultrasound device.

13. A flushless IVUS catheter according to any one of claims 1 to 5, for use in performing edge-based machine learning computations related to images or image analysis using an artificial intelligence algorithm to identify one or more of tissue boundaries, plaque, calcium, thrombus, dissection, and / or stent adhesion.

14. A flashless intravascular ultrasound (IVUS) catheter, An imaging core equipped with a rotating ultrasonic transducer connected to a drive shaft, An elongated member having an imaging tube lumen, The imaging lumen is configured to receive the imaging core having the rotating ultrasonic transducer and the acoustic coupling medium, The imaging tube lumen includes a proximal end, a distal end, and a wall extending to the length between the proximal end and the distal end. A long, slender member, A rigid connector hub comprising an internal chamber, an acoustic coupling medium-filled port, a distal interface, a proximal interface, and a flexible seal, The acoustic coupling medium filling port is configured to insert the acoustic coupling medium into the rigid connector hub in order to fill the imaging lumen. The distal interface is configured to connect to the proximal end of the imaging tube lumen. The proximal end of the imaging tube lumen is configured to be attached to the rigid connector hub. The aforementioned proximal interface is configured for connection to the interface module, The interface module is equipped with a motor. The flexible seal is connected to the seal housing connected to the proximal interface, The flexible seal is connected to the internal chamber of the rigid connector hub, The drive shaft extends distally through the flexible seal, Rigid connector hub and A flushless intravascular ultrasound (IVUS) catheter equipped with [feature / feature].

15. The flashless IVUS catheter according to claim 14, wherein the distal end of the imaging lumen includes a distal plug.

16. The flashless IVUS catheter according to claim 15, wherein the distal plug is inserted into the proximal end of the imaging lumen and is configured to be retracted into the distal end of the imaging lumen by a removable wire.

17. The flushless IVUS catheter according to claim 15, wherein the distal plug is configured to be joined to a part of the flexible wall adjacent to the distal end.

18. The flushless IVUS catheter according to claim 15, wherein the distal plug is made of polymer.

19. The flushless IVUS catheter according to claim 15, wherein the distal plug is joined to the distal port.

20. The flushless IVUS catheter according to claim 15, wherein the distal port is configured to be sealed by the distal plug.

21. The flushless IVUS catheter according to any one of claims 14 to 20, wherein the acoustic coupling medium is selected from the group consisting of polyethylene glycol (PEG), water, physiological saline, glycerin, and oil.

22. The motor is configured for electrical connection to the console, the console comprises a processor, and the processor is The motor is commanded to rotate the imaging core, The rotary transducer is instructed to generate an ultrasonic signal, The system receives a backscatter signal from the rotary transducer, and An ultrasonic image is generated based on the backscatter signal. A flushless IVUS catheter according to any one of claims 14 to 20, configured as described above.

23. The flashless IVUS catheter according to any one of claims 14 to 20, wherein the imaging core is mechanically connected to the drive shaft via the catheter interface module.

24. The flushless IVUS catheter according to claim 23, wherein the interface module comprises an actuator configured to rotate the drive shaft.

25. The flashless IVUS catheter according to claim 23, wherein the interface module comprises a transceiver configured to transmit and receive ultrasonic acoustic pulses.

26. The flushless IVUS catheter according to any one of claims 1 to 5 and 14 to 20, further comprising one or more strain relief components configured to prevent bending and excessive local strain within the IVUS catheter.

27. The flashless IVUS catheter according to any one of claims 1 to 5 and 14 to 20, further comprising a filling port cap configured to seal the acoustic coupling medium in the acoustic coupling medium filling port.

28. The flashless IVUS catheter according to any one of claims 1 to 5 and 14 to 20, wherein the IVUS catheter further comprises a filling port valve cap, the filling port valve cap having an opening for filling the acoustic coupling medium, and the filling port valve cap includes sealing the acoustic coupling medium to the sealed imaging lumen in the acoustic coupling medium filling port.

29. The flushless IVUS catheter according to any one of claims 1 to 5 and 14 to 20, further comprising a filling port cover configured to be inserted into and seal a filling port cap or filling port valve cap.

30. The flushless IVUS catheter according to any one of claims 1 to 5 and 14 to 20, wherein the rigid connector hub further comprises a drive bushing disposed around the drive shaft.

31. A flushless IVUS catheter according to any one of claims 1 to 5 and 14 to 20, further comprising one or more apertures disposed on the drive shaft, wherein the one or more apertures are configured to allow the acoustic coupling medium and bubbles to flow through the drive shaft.

32. A flushless IVUS catheter according to any one of claims 1 to 5 and 14 to 20, wherein a portion of the sealed inner lumen includes a substantially uniform wall thickness that forms an acoustic window around the rotating ultrasonic transducer.

33. A flashless intravascular ultrasound (IVUS) catheter, An imaging core equipped with a rotating ultrasonic transducer connected to a drive shaft, A flexible, elongated member having a sealed imaging tube lumen, The sealed imaging lumen is configured to receive the imaging core having the rotating ultrasonic transducer and acoustic coupling medium, The sealed imaging tube lumen includes a proximal end, a distal end, and a flexible wall extending to the length between the proximal end and the distal end. The distal end includes a distal port and a distal plug. A flexible, elongated member, A rigid connector hub comprising an internal chamber, an acoustic coupling medium-filled port, a distal interface, a proximal interface, and a flexible seal, The acoustic coupling medium filling port is configured to insert the acoustic coupling medium into the rigid connector hub to fill the sealed imaging lumen. The distal interface is configured to connect to the proximal end of the sealed imaging tube lumen. The proximal interface is configured for connection to a catheter interface module, the catheter interface module includes a motor and is configured for electrical connection to a console. The console is configured for controlling the rotational operation of the drive shaft, The flexible seal is distally connected to the seal housing connected to the proximal interface, The flexible seal is connected to the internal chamber of the rigid connector hub in a proximity, The drive shaft extends distally through the flexible seal. Rigid connector hub and Equipped with, The sealed imaging lumen is in communication with the flexible seal, the internal chamber, and the distal plug via a sealed acoustic coupling medium. Flashless intravascular ultrasound (IVUS) catheter.

34. The flushless IVUS catheter according to claim 33, wherein the acoustic coupling medium is selected from the group consisting of polyethylene glycol (PEG), water, physiological saline, and glycerin.

35. The console comprises a processor, and the processor is The actuator is commanded to rotate the imaging core, The rotary transducer is instructed to generate an ultrasonic signal, The system receives a backscatter signal from the rotary transducer, and An ultrasonic image is generated based on the backscatter signal. A flushless IVUS catheter according to claim 33, configured as described above.

36. The flashless IVUS catheter according to claim 33, wherein the imaging core is mechanically connected to the drive shaft via the catheter interface module.

37. The flushless IVUS catheter according to claim 33, wherein the catheter interface module comprises an actuator configured to rotate the drive shaft.

38. The flushless IVUS catheter according to claim 33, wherein the catheter interface module comprises a transceiver configured to transmit and receive ultrasonic pulses.

39. The flushless IVUS catheter according to any one of claims 33 to 38, further comprising one or more strain relief components configured to prevent bending and excessive local strain within the IVUS catheter.

40. The flashless IVUS catheter according to any one of claims 33 to 38, further comprising a filling port cap configured to seal the acoustic coupling medium in the acoustic coupling medium filling port.

41. The flashless IVUS catheter according to any one of claims 33 to 38, further comprising a filling port valve cap, the filling port valve cap having an opening for filling the acoustic coupling medium, and the filling port valve cap sealing the acoustic coupling medium to the sealed imaging lumen in the acoustic coupling medium filling port.

42. The flushless IVUS catheter according to any one of claims 33 to 38, further comprising a filling port cover configured to be inserted into and seal a filling port cap or filling port valve cap.

43. The flushless IVUS catheter according to any one of claims 33 to 38, wherein the rigid connector hub further comprises a drive bushing disposed around the drive shaft.

44. A flushless IVUS catheter according to any one of claims 33 to 38, further comprising one or more apertures disposed on the drive shaft, wherein the one or more apertures are configured to allow the acoustic coupling medium and bubbles to flow through the drive shaft.

45. The flashless IVUS catheter according to any one of claims 33 to 38, wherein the portion of the sealed imaging lumen includes a substantially uniform wall thickness that forms an acoustic window around the rotating ultrasonic transducer.

46. Intravascular ultrasound (IVUS) catheter, An ultrasonic transducer connected to a drive shaft, wherein the drive shaft is equipped with a coil, An elongated member having a sealed lumen, The sealed lumen is configured to receive the ultrasonic transducer and the acoustic coupling medium, The sealed lumen includes a proximal end, a distal end, and a wall extending to the length between the proximal and distal ends. A long, slender member, A rigid connector hub comprising an internal chamber, an acoustic coupling medium-filled port, a distal interface, a proximal interface, and a seal, The acoustic coupling medium filling port is configured to insert the acoustic coupling medium into the rigid connector hub to fill the sealed lumen. The distal interface is configured to connect to the sealed lumen, The proximal interface is configured to connect to a catheter interface module, and the catheter interface module is configured to rotate the drive shaft via an actuator. The catheter interface module comprises a transceiver configured to transmit and receive ultrasonic acoustic pulses, The seal is distally connected to the seal housing connected to the proximal interface, The seal is connected in proximity to the internal chamber of the rigid connector hub, The drive shaft extends distally through the seal. Rigid connector hub and Equipped with, The sealed lumen is in communication with the seal, the internal chamber, and the distal end via a sealed acoustic coupling medium. Intravascular ultrasound (IVUS) catheter.

47. It is a catheter, An ultrasonic transducer connected to a drive cable, A long, slender member having a lumen, The lumen is configured to receive the ultrasonic transducer and the acoustic coupling medium, The lumen includes a proximal end, a distal end, and a wall extending to the length between the proximal and distal ends. A long, slender member, A rigid connector hub comprising an internal chamber, a distal interface, a proximal interface, and a seal, The distal interface is configured to connect to the lumen, The seal is distally connected to the seal housing connected to the proximal interface, The seal is connected in proximity to the internal chamber of the rigid connector hub, The drive cable extends distally through the seal. Rigid connector hub and Equipped with, The lumen is in communication with the seal, the internal chamber, and the distal end via a sealed acoustic coupling medium. catheter.

48. A method for filling an intravascular ultrasound (IVUS) catheter with an acoustic coupling medium, The step of connecting an acoustic coupling medium source to an intravascular ultrasound (IVUS) catheter, The IVUS catheter comprises a flexible, elongated member and a rigid connector hub. The rigid connector hub comprises an inlet port and an internal chamber, The aforementioned flexible, elongated member comprises an inner lumen, an ultrasonic imaging core, and an outlet port. Steps and The steps include filling the inner lumen with the acoustic coupling medium via the inlet port, The steps include: discharging a portion of the acoustic coupling medium through the outlet port; The steps include sealing the aforementioned outlet port, The steps of sealing the aforementioned inlet port and Methods that include...

49. The method according to claim 48, further comprising the step of degassing the acoustic coupling medium.

50. The method according to claim 48, further comprising the step of heating the acoustic coupling medium.

51. The method according to claim 48, wherein the step of filling the inner lumen with an acoustic coupling medium includes the step of pushing the acoustic coupling medium into the inner lumen with positive pressure at the inlet port.

52. The method according to claim 48, wherein the pump is configured to push the acoustic coupling medium into the inner lumen under positive pressure at the inlet port.

53. The method according to claim 48, wherein the step of filling the inner lumen with an acoustic coupling medium includes drawing the acoustic coupling medium into the inner lumen by vacuum pressure at the outlet port.

54. The ultrasonic imaging core is positioned in the inner lumen of a flexible, elongated member. The ultrasonic imaging core includes a rotating ultrasonic transducer connected to the distal end of the drive shaft, The outlet port is located at the distal end of the inner lumen, The rigid connector hub further comprises a distal interface connected to the proximal end of the inner lumen. The method according to claim 48.

55. The method according to claim 48, wherein the step of sealing the outlet port includes the step of heating the plug in the outlet port.

56. The method according to claim 48, wherein the step of sealing the outlet port includes the step of bonding a plug to the outlet port.

57. The rigid connector hub further comprises a proximal interface having a flexible seal, The flexible seal is configured to seal a portion of the drive shaft that extends through the flexible seal, The proximal interface is configured to connect to a console, and the console is configured for the rotational operation of the drive shaft. The method according to any one of claims 48 to 56.

58. The method according to any one of claims 48 to 56, wherein the acoustic coupling medium is biocompatible, sterilizable, and acoustically compatible.

59. The method according to any one of claims 48 to 56, wherein the acoustic coupling medium is selected from the group consisting of polyethylene glycol (PEG), water, physiological saline, glycerin, and oil.

60. The method according to any one of claims 48 to 56, further comprising the step of adding a coloring agent to the acoustic coupling medium.

61. The method according to any one of claims 48 to 56, further comprising the step of mechanically agitating the ultrasonic imaging core of the IVUS catheter.

62. The method according to claim 61, wherein the step of mechanically stirring the ultrasonic imaging core includes the step of rotating the ultrasonic imaging core.

63. The method according to any one of claims 48 to 56, further comprising the step of orienting the IVUS catheter at a positive angle above the horizontal.

64. The method according to any one of claims 48 to 56, wherein the step of sealing the outlet port includes the step of sealing a polymer plug in the outlet port.

65. A method for filling a catheter with an acoustic coupling medium, A step of providing a catheter, The catheter comprises a flexible, elongated member and a rigid connector hub, The rigid connector hub comprises an inlet port and an internal chamber, The aforementioned flexible, elongated member comprises an inner lumen, an ultrasonic imaging core, and an outlet port. Steps and The steps include filling the inner lumen with an acoustic coupling medium via the inlet port, The steps include: discharging a portion of the acoustic coupling medium through the outlet port; The steps include sealing the aforementioned outlet port with a plug, The steps of sealing the aforementioned inlet port and Methods that include...

66. A method for filling an ultrasonic device with an acoustic coupling medium, The step of connecting the source of the acoustic coupling medium to the ultrasonic device, The ultrasonic device comprises a flexible, elongated member and a rigid connector hub. The rigid connector hub comprises an inlet port and an internal chamber, The aforementioned flexible, elongated member comprises an inner lumen and an ultrasonic imaging core. Steps and The steps include filling the inner lumen with the acoustic coupling medium via the inlet port, The steps of sealing the aforementioned inlet port and Methods that include...

67. The method according to any one of claims 65 to 66, further comprising the step of holding the acoustic coupling medium in the surrounding environment for a first period of time.

68. The method according to claim 67, wherein the first period is in the range of 30 to 300 minutes.

69. The method according to claim 67, wherein the first period continues until the acoustic coupling medium reaches an air saturation threshold.

70. The method according to claim 67, further comprising the step of holding the acoustic coupling medium in a vacuum environment for a second period to form a degassed acoustic coupling medium.

71. The method according to claim 70, wherein the second period is approximately 30 minutes to approximately 120 minutes.

72. The method according to claim 70, wherein the second period continues until the acoustic coupling medium reaches a desaturation threshold.

73. The method according to claim 72, wherein the desaturation threshold is based on an air saturation threshold.

74. The method according to claim 73, wherein the desaturation threshold is between approximately 5% or less of the air saturation threshold and approximately 50% or less of the air saturation threshold.

75. The method according to claim 73, wherein the desaturation threshold is about 20% or less of the air saturation threshold.

76. The method according to claim 65, further comprising the step of placing the catheter on a catheter heating plate.

77. The method according to claim 76, further comprising the step of heating the catheter to a target temperature of 35°C to 80°C.

78. The method according to any one of claims 65 to 66, further comprising the steps of: placing the acoustic coupling medium inside a syringe; and inserting the acoustic coupling medium into the inner lumen via a syringe pump device.

79. The method according to claim 78, wherein the syringe pump device comprises a syringe pump configured to discharge the acoustic coupling medium from the syringe at a target delivery rate.

80. The method according to claim 79, wherein the target delivery rate is 0.1 mL / min to 1.0 mL / min.

81. The method according to claim 78, wherein the syringe pump device comprises a syringe heating component configured to heat the syringe to a target temperature.

82. The method according to claim 81, wherein the target temperature is 35°C to 80°C.

83. The method according to claim 81, wherein the syringe heating component comprises a syringe jacket.

84. The method according to any one of claims 78 to 82, wherein the syringe pump device further comprises a rotary motor configured to rotate the imaging core in order to agitate and remove air from the sealed inner imaging tube lumen.

85. The method according to claim 84, wherein the rotary motor is configured to operate at a target speed.

86. The method according to claim 85, wherein the target velocity is based on one or more of the internal pressure of the syringe pump device and the internal pressure of the sealed inner lumen.

87. The method according to claim 86, wherein the target velocity is adjusted based on one or more of the following: the internal pressure of the syringe pump device exceeding a pressure threshold, or the internal pressure of the sealed inner lumen exceeding a threshold.

88. The method according to claim 87, wherein the pressure threshold is 50 psi to 150 psi.

89. The method according to claim 85, wherein the target speed is 900 to 1100 rpm.

90. It is a degassing system, A container configured to accept an acoustic coupling medium, A vacuum pump configured to be positioned in fluid communication with the aforementioned container, A hot plate configured to heat the aforementioned container, A container configured to receive a degassed acoustic coupling medium and Equipped with, The acoustic coupling medium is held in the container in the surrounding environment for a first period of time. The vacuum pump is positioned in fluid communication with the vessel and is configured to maintain the vessel at a vacuum pressure for a second period to convert the acoustic coupling medium into the degassed acoustic coupling medium. Degassing system.

91. The degassing system according to claim 90, wherein the first period is 30 minutes to 300 minutes.

92. The degassing system according to claim 90, wherein the first period continues until the acoustic coupling medium reaches an air saturation threshold.

93. The degassing system according to claim 90, wherein the second period is 30 to 120 minutes.

94. The degassing system according to claim 90, wherein the second period continues until the acoustic coupling medium reaches a desaturation threshold.

95. The degassing system according to claim 94, wherein the desaturation threshold is based on an air saturation threshold.

96. The degassing system according to claim 94, wherein the desaturation threshold is between approximately 5% or less of the air saturation threshold and approximately 50% or less of the air saturation threshold.

97. The degassing system according to claim 94, wherein the desaturation threshold is approximately 20% or less of the air saturation threshold.

98. The degassing system according to any one of claims 90 to 97, wherein the hot plate further comprises a magnetic stirring mechanism configured to rotate a magnetic stirring bar.

99. The degassing system according to claim 98, wherein the magnetic stirring bar is placed in the acoustically coupled medium for one or more of the first and second periods, and the magnetic stirring mechanism is configured to generate a magnetic field for rotating the magnetic stirring bar and to stir the acoustically coupled medium.

100. The degassing system according to any one of claims 90 to 97, wherein the hot plate is configured to heat the acoustic coupling medium to a first target temperature during the first period.

101. The degassing system according to any one of claims 90 to 97, wherein the hot plate is configured to heat the acoustic coupling medium to a second target temperature during the second period.

102. A system for filling IVUS catheters, A catheter heating plate configured to receive the IVUS catheter internally and heat the IVUS catheter to a target catheter temperature, It is a syringe pump, Accepting at least one syringe containing an acoustic coupling medium, The acoustic coupling medium is discharged from the at least one syringe at a target delivery rate. A syringe pump configured as follows, A syringe heating component configured to maintain at least one syringe at a target syringe temperature, A rotary motor configured to rotate the imaging core and agitate the air to remove it from the imaging lumen of the IVUS catheter. A system equipped with these features.

103. The system according to claim 102, wherein the target catheter temperature is 35°C to 80°C.

104. The system according to claim 102, wherein the target delivery rate is 0.1 mL / min to 1.0 mL / min.

105. The system according to any one of claims 102 to 104, wherein the syringe heating component is configured to maintain the syringe at the target syringe temperature for a syringe heating period of 1 to 20 minutes.

106. The system according to any one of claims 102 to 104, further comprising a pressure gauge disposed in fluid communication with the syringe pump and configured to detect the internal pressure of the syringe pump device.

107. The system according to any one of claims 102 to 104, wherein the rotary motor is configured to operate at a target speed between 900 and 1100 rpm.

108. The system according to any one of claims 102 to 104, wherein the syringe pump is configured to maintain the internal pressure of the system below a pressure threshold.

109. The system according to claim 108, wherein the pressure threshold is 40 psi to 120 psi.

110. The system according to claim 108, wherein the syringe pump is configured to stop discharging the acoustic coupling medium in response to the internal pressure exceeding the pressure threshold.

111. The system according to any one of claims 102 to 104, wherein the syringe pump is configured to change the target delivery rate in response to the internal pressure exceeding a pressure threshold at least once.

112. A catheter heating device, Insulating layer and, A heating layer disposed above the insulating layer, configured to heat the IVUS catheter to a target temperature, A catheter receiving layer positioned above a heating element, comprising a catheter notch, the catheter notch configured to receive the IVUS catheter, and A cover layer positioned above the catheter receiving layer and A catheter heating device equipped with the following features.

113. The catheter heating device according to claim 112, wherein the target temperature is at least about 35°C to at least about 80°C.

114. The catheter heating device according to claim 112, wherein the shape of the catheter notch is one of an "S" shape, a spiral shape, or a straight shape.

115. The catheter heating device according to claim 112, wherein the shape of the catheter notch is based on one or more characteristics of the IVUS catheter.

116. The catheter heating device according to any one of claims 112 to 115, wherein the catheter receiving layer further comprises one of a metal, a metal alloy, and a metal composite.

117. The catheter heating device according to any one of claims 112 to 115, wherein the catheter receiving layer contains aluminum.

118. The catheter heating device according to any one of claims 112 to 115, wherein the heating device further comprises one or more heating elements.

119. A flashless intravascular ultrasound (IVUS) catheter, An imaging core comprising a rotating ultrasonic transducer disposed within a transducer housing, wherein the transducer housing is connected to the distal end of a drive shaft via a coupling, A flexible, elongated member including a sealed imaging tube lumen, The sealed imaging lumen is configured to receive the rotating ultrasonic transducer and the acoustic coupling medium, The sealed imaging tube lumen includes a proximal end, a distal end, and a flexible wall extending to the length between the proximal end and the distal end. The distal end includes a distal port and a distal plug. A flexible, elongated member, A rigid connector hub comprising an internal chamber, an acoustic coupling medium-filled port, a distal interface, a proximal interface, and a flexible seal, One or more apertures located in one or more of the transducer housing, the coupling, and the drive shaft, configured to allow the acoustic coupling medium and bubbles to flow through one or more of the transducer housing, the coupling, and the drive shaft, and Equipped with, The acoustic coupling medium filling port is configured to insert the acoustic coupling medium into the rigid connector hub to fill the sealed imaging lumen. The proximal interface is configured for connection to a console, and the console is configured for controlling the rotational operation of the drive shaft. The proximal interface is configured for connection to a catheter interface module, the catheter interface module is configured to rotate the drive shaft via an actuator, and the catheter interface module includes a transceiver configured to transmit and receive ultrasonic acoustic pulses. The flexible seal is distally connected to the seal housing connected to the proximal interface, The flexible seal is connected to the internal chamber of the rigid connector hub in a proximity, The drive shaft extends distally through the flexible seal, The sealed imaging lumen is in communication with the flexible seal, the internal chamber, and the distal plug via a sealed acoustic coupling medium. catheter.

120. A kit including one or more of the catheters, hubs, seals, and plugs described herein, along with instructions for use.

121. Use of any of the apparatus, systems, and methods described in any of the preceding claims for non-therapeutic imaging.

122. Use of any of the apparatus, systems, and methods described in any of the preceding claims for imaging before, after, and / or simultaneously with the use of ultrasound as a treatment on the same or different systems.

123. The use of any apparatus, system, and method described in any of the preceding claims, wherein the term “IVUS catheter” is replaced with “ultrasound imaging device,” and such device is used to image a nonvascular lumen, cavity, or organ.

124. Use of any apparatus, system, or method described in any of the preceding claims, which causes a processor to perform edge-based machine learning computations related to an image.

125. Use of any of the apparatus, systems, and methods described in any of the preceding claims, configured for image analysis using an artificial intelligence algorithm for identifying one or more of tissue boundaries, plaque, calcium, thrombus, dissection, and / or stent adhesion.

126. Use of any apparatus, system, and method described in any of the preceding claims for imaging before, after, and / or simultaneously with the use of non-ultrasonic techniques as a treatment, wherein the non-ultrasonic techniques include mechanical thrombectomy and / or interventional coronary artery procedures.

127. Use of any apparatus, system, and method described in any of the preceding claims for minimally invasive imaging.

128. Use of any of the apparatus, systems, and methods described in any of the preceding claims for imaging intravascular tissue to identify irregularities, diseases, and / or injuries for medical treatment.

129. Use of any of the apparatus, systems, and methods described in any of the preceding claims for identifying lesions, plaques, thrombi, calcium accumulation, dissociation, and the measurement of any abnormalities thereof.

130. An ultrasonic transducer having one or more of the features described above.

131. A method of imaging using ultrasound having one or more of the characteristics described above.

132. A method for manufacturing any of the above-mentioned devices and systems having one or more of the features described above.

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