Irrigation-free intravascular ultrasound technology

Abstract

In certain aspects, systems and methods are provided for filling and sealing an irrigation-free intravascular ultrasound (IVUS) catheter using an acoustic coupling medium. The IVUS catheter includes, for example, an acoustic coupling medium inlet fill, a distal outlet port, a seal, and a stopper. The method of filling the IVUS catheter can advantageously reduce or eliminate bubbles in the acoustic coupling medium around the ultrasound imaging core rotating within the catheter imaging lumen. The method may include applying pressure to push the media into the lumen and / or evacuating to pull the media out of the lumen with a flexible seal and stopper to enclose the media within the catheter.

Description

[0001] Cross Reference to Related Applications

[0002] This application claims the benefit of U.S. Provisional Application No. US App. 63 / 459,312, filed April 14, 2023, entitled “Systems and Methods For Flush-Less Intravascular Ultrasound Catheter,” and U.S. Provisional Application No. US App. 63 / 546,091, filed October 27, 2023, entitled “Systems and Methods For Flush-Less Intravascular Ultrasound Catheter,” each of which is hereby incorporated by reference in its entirety. TECHNICAL FIELD

[0003] The present disclosure relates to the field of ultrasound, for example diagnostic and imaging applications that use ultrasound for medical purposes in some embodiments. Intravascular ultrasound (IVUS) imaging is provided in a number of embodiments. BACKGROUND

[0004] Ultrasound transducers, including transducers for intravascular imaging, employ one or more ultrasound elements to emit and / or receive acoustic signals through an acoustic coupling medium, such as a gel or fluid, in order to image and / or process tissue. Some standard IVUS catheters rely on flushing the internal lumen with a fluid to remove or reduce air bubbles around the ultrasound transducer to improve clarity in order to obtain satisfactory imaging. SUMMARY

[0005] Imaging and diagnosis of intravascular tissue and blood can be crucial, for example, in identifying irregularities, diseases, and / or injuries for medical treatment and can improve patient outcomes. Imaging clarity, for example, can be essential for the accurate identification of lesions, plaques (e.g., hard plaques, soft plaques, vulnerable plaques, calcified plaques, fibrofatty plaques, essentially non-calcified plaques), thrombi, blood clots, embolisms, calcifications, dissections, and measurements of these abnormalities. Imaging, such as IVUS imaging, can be used to plan treatment protocols and guide therapy selection in systemic interventional cardiology, vascular surgery, and interventional radiology, from the heart to peripheral vessels. In some embodiments, intravascular imaging-guided percutaneous interventions can be achieved by using the IVUS imaging improvements described herein. In some embodiments, an IVUS imaging system includes an imaging console (e.g., a workstation, computer, processor), a user interface (e.g., a tablet, controller), one or more displays, and an IVUS imaging catheter inserted into the patient's vascular system to image vascular anatomy. In some embodiments, the imaging console is a tablet, workstation, computer, display, user interface, or other control device that may contain a processor and / or software. The catheter interface module (CIM) can optionally connect the catheter to the console, or the catheter can optionally be directly connected to the console. Using standard IVUS catheters that require flushing with saline or similar fluid through an internal imaging lumen containing a rotating imaging core with a transducer, air bubbles around the imaging transducer within the lumen can obstruct ultrasound transmission and reception, resulting in blurred or poor-quality ultrasound images. Therefore, some embodiments described herein aim to address the air challenge by providing catheters pre-filled in a bubble-free manner within an acoustic coupling medium (e.g., coupling medium, medium, liquid, fluid, gel, etc.).

[0006] In some embodiments, the technologies described herein, including, for example, IVUS flush-free technology, are used in conjunction with other medical imaging systems (e.g., cardiac catheterization lab systems) to provide cardiologists with an integrated healthcare portfolio. In some embodiments, integrated or otherwise coordinated platforms 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 removal, balloon placement, etc.) are optimized using the IVUS technologies described herein, along with X-ray, extracorporeal ultrasound, and / or other non-IVUS technologies.

[0007] In some embodiments, the IVUS technology described herein is used in conjunction with other catheter-based and / or non-catheter-based imaging procedures. 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, two-dimensional imaging, three-dimensional imaging, etc. Some embodiments described herein utilize simultaneous operation, imaging, and / or measurement from two, three, or more imaging modalities (e.g., ultrasound, X-ray (including radiography, fluoroscopy, angiography, venography, etc.), MRI, PET scans, optical imaging (e.g., optical coherence tomography, light imaging, laser imaging), etc.). Multimodal collaboration between IVUS and one or more additional imaging systems has been implemented in some embodiments, including, for example, enhanced visualization and image quality, reduced procedure time, improved accuracy of stent placement and vascular measurement, improved workflow and reliability, and other advantages. For example, multimodal systems, including IVUS, can be used to allow cardiologists to diagnose and / or treat vascular blockages and other defects, thereby providing patients with improved cardiac outcomes while reducing the overall cost burden of healthcare systems through efficient and effective integration with IVUS. Using various embodiments of the IVUS technology described herein, more robust images of vascular and organ structures, such as cardiac structures, can be obtained.

[0008] In some embodiments, the proximal connector hub (i) is securely locked onto the CIM or console and is easily unlocked upon removal; (ii) mates with and is electrically connected to a CIM or console socket; (iii) mates with a motor drive shaft in the CIM or console socket and maintains concentric rotation of the rotation shaft; (iv) seals the acoustic coupling medium within a conduit lumen distal to the seal; and / or (v) supports the filling port of the acoustic coupling medium. In some embodiments, the drive shaft may optionally include a drive cable, a drive coil, a transmission system, and / or a drive actuator. Some embodiments provide a rigid proximal connector hub with a seal (e.g., a flexible seal, where flexibility in some embodiments refers to elasticity, stretchability, bendability, modifiability, adjustability, adaptability, fitability, toughness, softness, compliance, and / or resilience) as part of a conduit to support the encapsulated acoustic coupling medium while allowing internal imaging core rotation without media leakage and preventing air ingress into the imaging lumen. In some embodiments, one or more seals are disposed within the rigid connector hub. In some embodiments, the seal is not placed within a flexible structure, such as a flexible conduit or flexible lumen. In various embodiments, the seal may be placed within a rigid structure. In some embodiments, a flexible seal (e.g., an O-ring, other circular seals, or seals of other shapes) surrounds the drive shaft (e.g., drive cable, drive coil, transmission system, drive actuator) of a rotating imaging core within a rigid proximal connector hub, holding the medium within a lumen connected to the hub as the core rotates. In some embodiments, the seal remains stationary relative to the drive shaft, stationary relative to the conduit wall, and / or does not move with or relative to the drive shaft and conduit wall (e.g., no translation or linear movement). In some embodiments, the seal is distanced from, separated from, and does not contact the motor. A circular seal can be pressed against the drive shaft with sufficient force to prevent leakage while still allowing the motor (e.g., connected to an imaging console) to rotate the internal imaging core at a rate supporting high imaging frame rates. Example seal materials include elastic polymers such as acrylic fibers, ethylene propylene rubber, and fluorocarbon compounds and similar materials. Hub assemblies and features may be arranged to secure the flexible seal between the connector hub and the rotating drive shaft, such as, for example, a sealing shell and / or a sealing cap. The inner diameter / surface of the sealing housing can be precisely sized to ensure appropriate pressing force is applied to the flexible seal to allow the drive shaft to rotate without excessive friction, while preventing media leakage to the proximal side through the flexible seal. Optionally, an adhesive can be applied to the outer periphery of the flexible seal to prevent leakage around the flexible seal. The flexible seal can be assembled within a rigid proximal connector hub to ensure a precise fit. In some embodiments, this is more advantageous than placing the seal within a flexible conduit or similar conduit body / lumen, as flexibility can lead to media leakage or air ingress during use.During normal operation in a typical clinical environment, the pressure differential across the flexible seal may typically be small, so according to some embodiments, there is little force to expel the medium or draw in air. However, outside the clinical operating room, such as during product transport, the catheter may be exposed to extreme temperatures and fluctuations in ambient temperature. When exposed to extreme temperature drops or rises, the volume of the coupling medium may decrease or increase, respectively, and then return to its default volume after exposure to extreme temperatures. In some embodiments, such volume changes may typically require a certain sealing force to prevent air from being drawn in or fluid from leaking out of the internal imaging lumen. Air entering the lumen may migrate to the distal transducer of the rotating imaging core and degrade image quality. In one embodiment, a dual-sealed shell may be preferred for precise assembly and sealing, but a single shell may also be used only on the proximal side. According to some embodiments, a filling port is included within the rigid proximal connector hub and sealed after the catheter lumen is filled with medium. The filling port may be configured for easy connection to a filling device. After the catheter lumen is filled, the filling port may be closed, for example using seals, plugs, stoppers, and / or adhesives, to prevent any air from entering. According to some embodiments, the techniques described herein, including IVUS flush-free technology, include a reversible flush port seal that allows for product rework after inspection (e.g., checking for remaining air bubbles, image quality, etc.) and before optionally permanent sealing. In some embodiments, the reversible port seal(s) can be used to repeat filling and / or flushing procedures until satisfactory results are achieved (e.g., air bubbles are removed, etc.). In one embodiment, the seal is reversible. In one embodiment, the seal is permanent. In some embodiments, the fill port may be temporarily sealed to facilitate inspection and permanently sealed after confirmation of successful filling. In some embodiments, the temporary seal of the fill port may be removed to facilitate further fluid filling process steps. In one embodiment, the fill port has a proximal inlet juxtaposed with a flexible seal to help remove all air bubbles during the filling process. In some embodiments, a portion of the acoustic coupling medium exits the imaging lumen of the IVUS catheter through a distal port (e.g., outlet port, discharge port, vent, orifice, orifice, channel, opening) (e.g., during the filling process). In some embodiments, the distal port extends perpendicular to the longitudinal axis of the catheter through the catheter wall, and the distal port does not extend along the longitudinal axis of the catheter along a distance in the catheter wall.

[0009] The embodiments of this document also provide a method for sealing an outlet port after filling an imaging lumen. In one embodiment, a distal plug is attached to a removable wire. Some embodiments of this document also provide designs and methods for discharging and sealing an internal imaging lumen (e.g., discharging and sealing an outlet port and a filling port during or after filling an internal imaging lumen). In one embodiment, a plug is formed at the distal end, which is fused to the distal end of the imaging lumen, thereby sealing the imaging lumen. During the fusion process, a removable wire can be placed next to the plug and then removed, effectively forming a narrow channel for discharging during filling. The removable wire may include, for example, NiTi (nickel-titanium alloy), stainless steel, or other wires. The wire dimensions can be configured to form an effective discharge port that can be easily sealed after the filling process, for example, by heating or adhesives. In one embodiment, the wire size ranges from 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).

[0010] According to some embodiments, the filling process is completed once all air bubbles have been removed from the imaging lumen and air is discharged from the outlet. After checking for air bubbles, the outlet and the distal plug are sealed closed by a heating process that recirculates the material together and / or by inserting a small amount of adhesive into the outlet. In one embodiment, the distal end may be formed by the distal plug and a removable wire located at the distal end of the imaging lumen. The removable wire includes, for example, NiTi (nickel-titanium alloy), stainless steel, or other materials (e.g., metal, alloy, rigid, and / or flexible wire). According to some embodiments, (i) the wire is fed through the lumen and exits from the outlet port, allowing the distal plug to float loosely in the distal portion of the lumen; (ii) the filling process is completed once all air bubbles have been removed from the lumen and air is discharged from the outlet port; (iii) after checking for air bubbles, the distal plug is bonded to the lumen wall, either by a heating process that recirculates the material together and / or by inserting a small amount of adhesive into the outlet port. After the distal plug is attached to the conduit lumen, the wire can be easily removed from the plug. Before the filling process begins, a colorant can be added to the medium to help check for leaks and identify air bubbles. The colorant can selectively increase optical contrast, thereby aiding in the identification of the medium and air bubbles, thus improving the manufacturing process.

[0011] In some embodiments, the catheter optimized for vascular imaging is configured to have excellent maneuverability, trackability, and the ability to traverse the peripheral vascular system of arteries and veins. In some embodiments, one or more of the following features are provided:

[0012] Maneuverability: In some embodiments, the catheter has excellent maneuverability to avoid kinking and sufficient column strength to allow it to pass through bends and occlusions in the vascular system without buckling, excessive bending, or collapsing anywhere along the catheter (e.g., proximal or (e.g., the ability to pass through occlusions or constrictions)). In some embodiments, material properties (e.g., the balance of rigidity and flexibility, the stiffness of individual segments) and dimensional characteristics (e.g., larger dimensions, such as diameter and thickness) increase column strength, resulting in greater maneuverability and resistance to kinking.

[0013] Tracking: In some embodiments, the catheter has excellent tracking capabilities, enabling it to follow the guidewire through bends and twists in the vascular system, and possesses sufficient flexibility and strength to move along the guidewire and advance to a target location within the vascular system. According to some embodiments, a hydrophilic coating helps reduce friction with the guidewire and surrounding luminal tissue. In various embodiments, the hydrophilic coating is located on the outer and / or inner surface of the catheter (e.g., within 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., within the lumen).

[0014] Crossing: In some embodiments, the catheter has excellent crossing capability to cross occlusions, restrictions, and constrictions within the vascular system, such as sites with tissue obstruction (e.g., stenosis) and / or implant obstruction (e.g., stents, balloons, etc.). According to some embodiments, crossing capability is enhanced by one or more of the following: (i) the design of the distal end (e.g., sufficiently sharp to bypass occlusions, etc., and sufficiently blunt to avoid being hooked by occlusions), (ii) material properties (e.g., a balance of rigidity and flexibility, stiffness of different segments, etc.), and / or (iii) dimensional characteristics (e.g., larger dimensions, such as diameter and thickness, increasing column strength). In one embodiment, lower stiffness is provided near the distal end to allow flexibility to bypass tortuous anatomy and obstructions. In one embodiment, a varying or stepped gradient region is provided that gradually changes towards higher stiffness proximally, sufficient to move the catheter while avoiding kinking. A single stiffness and / or flexibility may remain constant along one or all parts of the device.

[0015] Several embodiments described herein provide an IVUS catheter with a proximal connector hub assembly that facilitates an improved process for filling the IVUS catheter with an acoustic coupling medium. In some embodiments, the internal lumen of the IVUS catheter is configured as an imaging lumen and includes an imaging transducer. In some embodiments, a filling port is designed to encapsulate the acoustic coupling medium within the imaging lumen and around the transducer. In various embodiments, the acoustic coupling medium preparation process, the coupling medium filling apparatus and process, and the structural components are all configured with design features to aid in the removal of air from the catheter body. In some embodiments, the proximal connector hub assembly may include a proximal connector hub with a filling port, a filling port cap, and a filling mask. The filling port may receive the filling port cap, which may be a resilient sealing component or a rigid plastic cap. The filling port cap may mate with a filling adapter for a filling nozzle, which can be used to fill the IVUS catheter with the acoustic coupling medium. In one embodiment, if the filling port cap is a resilient seal, the filling nozzle may include a needle that pierces the seal to fill the catheter. Once the IVUS catheter is filled, the filling nozzle and filling port adapter can be disengaged from the filling port cap, allowing acoustic coupling medium to be drawn into the cap and preventing air from entering the internal imaging lumen of the IVUS catheter. In some embodiments, the internal lumen is configured as the imaging lumen. In some embodiments, the imaging lumen is the internal lumen. Once the IVUS catheter is filled, the filling nozzle and / or filling port adapter can be disengaged from the filling port cap, which can then be covered by a filling mask. In some embodiments, the proximal connector hub assembly may include a proximal connector hub with a filling port, a filling port valve cap, and a filling mask. The filling port may receive the filling port valve cap. The filling port valve cap may cooperate with a filling adapter for the filling nozzle, which can be used to fill the IVUS catheter with 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, allowing acoustic coupling medium to be drawn into the cap and preventing air from entering the internal imaging lumen of the IVUS catheter. In some embodiments, the catheter connector hub (i) is securely locked in the catheter interface module and easily unlocked during removal; (ii) mates with and establishes an electrical connection with the catheter interface module socket; (iii) mates with and maintains concentric rotation of the rotation axis with the motor drive shaft in the catheter interface module socket; (iv) seals the acoustic coupling medium within 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 include a drive cable, a drive coil, a transmission system, and / or a drive actuator.

[0016] The proximal connector hub may include a strain relief assembly that reduces or prevents kinking and excessive localized strain in the IVUS conduit. According to some embodiments, the proximal hub connector may also include a seal, a drive bushing, a drive hub, a drive pin, and / or an electronic identification (EID) printed circuit board (PCB). The drive bushing reduces wobbling and / or non-uniform rotational deformation (NURD) and prevents acoustic coupling medium leakage by maintaining uniform friction around the inner diameter of the seal.

[0017] Several methods described herein are used for degassing the acoustic coupling medium and filling the IVUS catheter with the degassed medium, which, in some embodiments, advantageously eliminates the need for user preparation and fluid flushing of the lumen surrounding the internal imaging core. Furthermore, some embodiments of the methods described herein advantageously prevent the introduction of air into the acoustic coupling medium during filling, which improves the image quality captured by the IVUS catheter and reduces procedure time by eliminating the need for refilling or replacing the IVUS catheter, among other advantages discussed herein.

[0018] In some embodiments, the degassing process includes subjecting the acoustic fluid to a vacuum or low pressure for a period of time. In one embodiment, the degassing process may begin by providing a degassing device. This device may include a container, a vacuum pump, a magnetic stir plate, a hot plate, and / or a syringe. The container may be connected to the vacuum pump via a conduit and a first valve, such as a diverter valve. The container may be connected to the syringe via a second valve, such as a stopcock valve. The acoustic coupling medium may be placed in the container and held for a first time period. This first time period may be a predetermined time period or may continue until the acoustic coupling medium reaches an air saturation threshold. After the first time period, the acoustic coupling medium may be held under vacuum pressure for a second time period. This second time period may be a predetermined time period as described below or may continue until the acoustic coupling medium reaches a desaturation threshold. Once the acoustic coupling medium reaches the desaturation threshold, the medium can be transferred to the syringe. In one embodiment, the medium can be transferred to the syringe via a conduit and a second valve. In one embodiment, the magnetic stir plate is a hot plate, and the degassing process further includes heating the acoustic coupling medium to reduce the fluid viscosity to facilitate a subsequent filling process.

[0019] An IVUS catheter can be filled using a degassed acoustic coupling medium. In some embodiments, the filling process may begin by providing an IVUS catheter filling device, which may include a fluid pump—such as an injection 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 cut for receiving the IVUS catheter. This cut may be S-shaped, spiral-shaped, a straight path, etc., and may be shaped based on one or more properties of the IVUS catheter.

[0020] The syringe pump device accepts a syringe filled with degassed acoustic coupling medium. The syringe pump device may include a syringe pump, a syringe heating assembly (e.g., a syringe sleeve), a pressure gauge, at least one piece of tubing, a pump, and / or a three-way valve. The syringe pump receives the syringe, and the syringe heating assembly may be positioned around the syringe and heat the syringe to a target temperature in the range of 35°C–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 ​​thereto). The syringe pump displaces the acoustic coupling medium from the syringe through the pressure gauge and into the tubing. In some embodiments, the syringe pump may displace the acoustic coupling medium at a target delivery rate, e.g., 0.4 mL / min. The delivery rate may be modified based on whether the pressure within the syringe pump device or the IVUS tubing exceeds a pressure threshold, e.g., 80 psi. In some embodiments, the syringe pump may displace the acoustic coupling medium at a target filling pressure.

[0021] Acoustic coupling medium can be delivered to the pump via a valve, such as a three-way valve, through conduit. 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 pull / push the acoustic coupling medium from the conduit and / or syringe and into the proximal connector hub of the IVUS catheter to fill the catheter imaging lumen. According to some embodiments, the pump can also expel air from the imaging lumen of the IVUS catheter, for example, through an vent in the catheter, as described herein.

[0022] Several embodiments described herein provide an IVUS conduit having one or more features that allow for easier filling of the conduit with an acoustic coupling medium while minimizing the risk of air being introduced into the medium and / or the conduit imaging lumen. The IVUS conduit may include an imaging core disposed within a conduit sheath. The imaging core may include a wired transducer coupled to a transducer housing, and the transducer housing is coupled to a coil via a coupler within the imaging lumen. A drive shaft may be attached proximally to the coil. According to some embodiments, the transducer, transducer housing, and / or coupler may include one or more orifices. According to some embodiments, the drive shaft may also include one or more orifices. The IVUS conduit may include a first lumen gap between the imaging core and the coil, and a second gap between the coil and the conduit sheath. 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 between these one or more orifices and / or the first and second gaps throughout the IVUS conduit can reduce resistance to medium flow during air expulsion from the coil within the IVUS conduit, increase the speed and efficiency of IVUS conduit filling, and improve and make bubble removal more effective. This can optionally improve the overall quality of IVUS images captured by the IVUS catheter. In some embodiments, to aid in the filling process that removes air from the imaging lumen inside the catheter, the acoustic coupling medium can be filled while the inner core is rotated at a target speed of, for example, 1000 rpm ± 100 rpm. If air is introduced into the system during filling, the target speed can be modified. For example, if air is introduced, the target speed can be reduced.

[0023] Some embodiments described herein provide an IVUS catheter having a rotating internal imaging core encapsulated in an imaging lumen by a medium, which advantageously eliminates the need for user preparation and flushing of the lumen surrounding the internal imaging core with fluid. Furthermore, IVUS catheters according to various embodiments do not require a telescopic portion connected to a motorized unit to achieve imaging of the vascular system using the rotating imaging core, thereby simplifying IVUS catheter design. In some embodiments, the catheter does not have a telescopic portion that moves along the longitudinal axis of the catheter. In some embodiments, the catheter does not have a movable plunger or a movable seal. Some embodiments of methods for reliably filling an IVUS catheter with a coupling medium are also disclosed, supporting imaging without air interference hindering high-quality imaging.

[0024] In various embodiments, the catheter assembly includes a rapid exchange (RX) guidewire lumen or an over-the-wire (OTW) guidewire lumen. In some embodiments, a catheter assembly comprising an RX guidewire lumen or an OTW guidewire lumen is provided. In one embodiment, the catheter further includes an internal imaging lumen supporting an imaging core with a rotary drive shaft and a distally housed transducer. This imaging lumen may be filled with an acoustic coupling medium (e.g., a liquid, fluid, gel, etc.). For example, in one embodiment, a liquid is a suitable medium because it may be easier to fill the lumen and remove air from the liquid. The IVUS catheter in contact with blood may optionally be biocompatible and sterilizable. According to embodiments, the acoustic coupling medium may also be biocompatible and sterilizable because there may be a risk of medium entering the bloodstream if there is a leak in the catheter. In one embodiment, the acoustic coupling medium may have a density and sound velocity value similar to the catheter sheath material in some embodiments. Increased differences in density or sound velocity values ​​between the medium and the catheter sheath can lead to unwanted strong acoustic reflections and refractions of sound pulses, which can degrade image quality. In some embodiments, the sound velocity value of the acoustic coupling medium is configured to improve lateral performance. In one embodiment, the geometry of the rotating element conduit may include an ultrasonic focusing lens made of a slightly raised circular material on the transducer surface, with a sound velocity slightly lower than that of the imaged material. In one embodiment, a tightly curved, high-velocity shell (conduit body) and its internal material (coupling medium) may be selected, with a sound velocity close to or sometimes higher than that of the imaged material. In one embodiment, the design of the rotating conduit geometry—with its thin, relatively high-velocity conduit body and its internal coupling medium—can be configured to have a fairly advantageous focusing effect. This embodiment may be configured unexpectedly because the ultrasonic focusing lens is made of a slightly or slightly raised circular material on the transducer surface, with a sound velocity slightly lower than that of the imaged material. In one embodiment, a tightly curved, high-velocity shell (conduit body) and its internal material (coupling medium) may be selected, with a sound velocity close to or even higher than that of the imaged material. In some embodiments, the medium includes one of polyethylene glycol (PEG), PEG containing a portion of water, water, saline, glycerin, and natural oils. The percentage of non-PEG components can be from 20% to 80% (e.g., 80%, 70%, 60%, 50%, 40%, 30%, 20% and overlapping values ​​and ranges therein), and in some embodiments, the percentage of non-PEG components can be from 30% to 50% (e.g., 50%, 45%, 44%, 43%, 42%, 41%, 40%, 39%, 38%, 37%, 35%, 35%, 30% and overlapping values ​​and ranges therein), because the latter has a lower tendency to dissolve gases. In some embodiments, the coupling medium comprises one or more fluids.

[0025] Some embodiments provide a rigid proximal connector hub with a seal (e.g., a flexible seal, wherein in some embodiments, flexibility refers to elasticity, stretchability, bendability, modifiability, adjustability, adaptability, fitability, suppleness, softness, compliance, and / or resilience) as part of a conduit to support the encapsulated acoustic coupling medium while allowing the internal imaging core to rotate without leakage of the medium and preventing air from entering the imaging lumen. In some embodiments, the flexible seal (e.g., an O-ring, other circular seals, or seals of other shapes) surrounds a drive shaft (e.g., a drive cable, drive coil, transmission system, drive actuator) of the rotating imaging core located within the rigid proximal connector hub, which retains the medium within the lumen connected to the hub as the core rotates. A circular seal can be pressed against the drive shaft with sufficient force to prevent leakage while still allowing a motor (e.g., connected to an imaging console) to rotate the internal imaging core at a rate supporting high imaging frame rates. Example sealing materials include, for example, elastic polymers of acrylic fibers, ethylene propylene rubber, and fluorocarbon compounds and similar materials. Hub assemblies and features can be arranged to secure a flexible seal between the connector hub and the rotary drive shaft, such as, for example, a sealing housing and / or a sealing cap. The inner diameter / surface of the sealing housing can be precisely sized to ensure that appropriate pressing force is applied to the flexible seal, allowing the drive shaft to rotate without excessive friction, while also preventing media leakage proximally through the flexible seal. Optionally, an adhesive can be applied to the outer periphery of the flexible seal to prevent leakage around the flexible seal. The flexible seal can be assembled within a rigid proximal connector hub to ensure a precise fit. In some embodiments, this is advantageous over placing the seal within a flexible catheter or similar catheter body / lumen, as flexibility may facilitate media leakage or air ingress during use. During normal operation in a typical clinical environment, the pressure differential across the flexible seal may typically be small, so according to some embodiments, there is little force to expel the media or draw in air. However, outside the clinical operating room, such as during product transport, the catheter may be exposed to extreme temperatures and fluctuations in ambient temperature. When exposed to extreme temperature drops or rises, the volume of the coupling media may decrease or increase, respectively, before returning to its default volume after exposure to extreme temperatures. In some embodiments, this volume change may typically require a certain sealing force to prevent air from being drawn into the internal imaging lumen or liquid from leaking from it. Air entering the lumen may migrate to the distal transducer of the rotating imaging core and degrade image quality. In one embodiment, a double-sealed housing may be preferred for precise assembly and sealing, but a single housing may also be used only on the proximal side. According to some embodiments, a filling port is included in the rigid proximal connector hub and is sealed after the lumen is filled with the medium. The filling port may be configured for easy connection to a filling device. After the lumen is filled, the filling port can be sealed with, for example, a seal, plug, stopper, and / or adhesive to prevent any air ingress.In one embodiment, the filling port has an inlet on the nearest side, juxtaposed with a flexible seal to help expel all air bubbles during the filling process.

[0026] In some embodiments, a portion of the acoustic coupling medium exits the imaging lumen of the IVUS catheter through a distal port (e.g., an outlet port, vent, orifice, orifice, channel, opening) (e.g., during the filling process). Methods for sealing the outlet port after filling the imaging lumen are also provided in embodiments herein. In one embodiment, a distal plug is attached to a removable cable. Designs and methods for venting and sealing the internal imaging lumen are also provided in some embodiments herein (e.g., venting and sealing the outlet port and filling port during or after filling the internal imaging lumen).

[0027] In one embodiment, a plug is formed at the distal end, which is fused to the distal end of the imaging lumen to seal the imaging lumen. During the fusion process, a removable wire can be placed next to the plug and then removed, effectively creating a narrow channel for venting air during the filling process. The removable wire may include, for example, NiTi (nickel-titanium alloy), stainless steel, or other wires. The wire size can be configured to form an effective vent that can be easily sealed after the filling process, for example, by heating or adhesive. In one embodiment, the wire size ranges from 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, the filling process is complete once all air bubbles have been expelled from the imaging lumen as air is expelled from the vent; and after a check for air bubbles, the vent and the distal plug are sealed, either by a heating process that allows the material to flow back together, and / or by inserting a small amount of adhesive into the vent. In one embodiment, the distal end may have a distal plug and a removable wire formed at the distal end of the imaging lumen. The removable wire includes, for example, NiTi (nickel-titanium alloy), stainless steel, or other materials (e.g., metal, alloy, rigid, and / or flexible wire). According to some embodiments, (i) the wire is fed through the lumen and exits from the outlet port, allowing the distal plug to float loosely in the distal portion of the lumen; (ii) the filling process is completed once all air bubbles are removed from the lumen by venting air from the outlet port; and (iii) after inspection for air bubbles, the distal plug is bonded to the wall of the lumen, or bonded to the lumen wall using a heating process that recirculates the material together, and / or by inserting a small amount of adhesive into the outlet port. After the distal plug is bonded to the lumen, the wire can be easily removed from the plug. A colorant may be added to the medium before the filling process begins to aid in checking for leaks and identifying air bubbles. Colorants can selectively increase optical contrast, thereby helping to identify media and bubbles and thus improving the manufacturing process.

[0028] In some embodiments, methods are also provided for encapsulating a medium, such as a fluid, within the lumen of an IVUS conduit to prevent bubble formation or trapping during the filling process. A vacuum pump may be attached to a distal outlet port to remove air from the conduit lumen, and then an inlet valve may be opened to allow the medium to be drawn into the lumen. A pump may also be used instead of a vacuum pump to push in the medium, or in combination with a vacuum pump used to pull in the medium. A pump (e.g., a peristaltic pump or other pump) is an example of a useful pump mechanism for pushing.

[0029] In some embodiments, filling the imaging lumen with media using vacuum pulling and / or pumping can be supplemented by degassing the media prior to filling. Undegassed media are typically saturated and contain dissolved gases from the surrounding environment, which may escape from the solution during the filling process or within the device's shelf life, creating bubbles during and after the filling process, which in turn interfere with imaging during use. These bubbles may adhere to surfaces, especially uneven surfaces, making it difficult to completely remove air from the lumen. In some embodiments, the coupling media is degassed before being pulled in and / or pushed into the lumen. In some embodiments, its exposure to ambient air is further minimized before the filling process begins. The degassed liquid can remain undersaturated for a practical time period (the actual filling period) during which the lumen can be filled. This reduces the risk of air escaping from the solution during the filling process and can further absorb bubbles that may be present during the filling process. Absorbing bubbles with a properly degassed media can be an effective mitigation method, as these bubbles remain in the solution and do not reappear. Using a suitable degassing medium, the pressure within existing bubbles can selectively force the internal air to dissolve into the medium, thereby eliminating trapped bubbles. In one embodiment, selectively degassing the medium reduces the number of visible bubbles in the medium.

[0030] The maximum period during which the solution maintains its undersaturated state, and therefore the period available for the filling process, depends in some embodiments on the media type, degassing procedure, and post-processing media handling reservoir. In one embodiment, the maximum period can be determined experimentally by using an oxygen sensor placed in a representative media to measure the oxygen content in the media for comparison with the oxygen content in ambient air. For example, PEG400, a fluid with a viscosity of about 100 cP after proper degassing, has an actual filling period of less than two hours, which supports a manufacturing process that can be used to fill the lumen within a portion of one hour immediately after the degassing step is completed.

[0031] During the media filling process, the media can be heated, for example by heating a reservoir used to degas the coupling media and / or the tube and / or the catheter itself used to fill the catheter lumen. Heat can reduce viscosity, thereby shortening the filling time of the catheter lumen, and can further reduce dissolved gases in the media. Temperatures above ambient temperature can reduce the viscosity of the media, and dissolved gases at higher temperatures further improve the filling effect. In various embodiments, the coupling media is heated to a temperature in the range of 60-100°C (e.g., 60, 65, 70, 75, 80, 85, 90, 95, 100°C, and overlapping values ​​and ranges thereto). In one embodiment, 60°C is a useful temperature because burns can be avoided if someone touches the catheter or device. Higher temperatures, such as below 100°C, can further facilitate preventative measures against accidental contact during the filling process. Air bubbles may also be present in other cavities or interfaces within the catheter imaging lumen, such as inside the imaging core or inside the proximal hub connection to the imaging lumen. These other cavities may be difficult or impossible to detect air bubbles during and after the filling process. Therefore, air bubbles may be present after the filling process is completed but go undetected and may appear later during clinical use. The several procedures for degassing the coupling medium and filling the catheter described in the examples herein can significantly reduce the risk of undetected air bubbles and reduced image quality. In rotating IVUS catheters, there may be drive cables or coils, as well as cables inside the drive cables or coils. The space along the entire length of the catheter, inside and around the drive cables, is a space where air may not be easily and completely removed; therefore, degassing the coupling medium will help remove air from hidden cavities.

[0032] 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 can result from vibration of the catheter and / or rotation of the internal imaging core. In one embodiment, the catheter may optionally be held vertically or at a positive angle above the horizontal plane, allowing gravity to cause air bubbles to migrate upwards out of the outlet port; in some cases, this is performed to facilitate the release of air bubbles and observation of an acceptable filling process.

[0033] Visual inspection reveals that all air bubbles have been completely removed from the distal outlet port of the catheter, which can be used to signal the cessation of the filling process and the time-based verification process.

[0034] In some embodiments, an IVUS catheter is provided, comprising: (i) an elongated flexible member having a sealed lumen; (ii) a rigid proximal connector hub attached to the elongated member, the elongated member being connected to a console; (iii) an imaging core movable within an imaging lumen, the imaging core including a rotary drive shaft and a distal ultrasonic transducer; and (iv) a flexible seal within the rigid proximal connector hub, the flexible seal sealing media within the imaging lumen between the drive shaft and the flexible member, wherein the acoustic coupling medium does not leak out of the lumen, and air does not enter through the flexible seal, and wherein the console actuates the transducer and receives signals for forming an image. In some embodiments, the drive shaft may optionally include a drive cable, a drive coil, a transmission system, and / or a drive actuator. Optionally, the distal end of the internal imaging lumen may include a distal port and a distal plug.

[0035] In some embodiments, the method for media filling includes: (i) placing a flexible seal within a rigid proximal connector hub and sealing it with a coupling medium within an elongated flexible member cavity, wherein the coupling medium is biocompatible, sterilizable, and acoustically compatible; (ii) degassing the medium (fluid or gel) prior to filling the cavity to remove some dissolved gases from the medium; (iii) drawing and / or pushing the medium into and / or into the cavity using a vacuum; (iv) sealing the inlet port; and (v) sealing the outlet port. In some embodiments, the medium is polyethylene glycol (PEG), PEG containing a certain proportion of water, water, brine, glycerin, and / or natural oils.

[0036] Optionally, the media filling method includes one or more of the following: propelling the media with a pump, such as a peristaltic pump, syringe pump, or displacement pump; pulling the media with a vacuum pump attached to the distal outlet port; introducing mechanical agitation to promote more effective air removal; vertical or non-horizontal orientation of the conduit to support gravity-assisted effective air removal from the lumen; heating the media and / or heating the conduit lumen to promote air removal from the media while reducing viscosity to accelerate the filling process; sealing the outlet port with a polymer plug; and using heat to melt the polymer plug into a sleeve or adhesive to bond the interface.

[0037] In various embodiments, a flush-free rotating imaging core IVUS catheter is provided, which can be removed from the package for use after the rigid proximal connector hub is inserted into the imaging console, thereby improving ease of use. In one embodiment, the absence of a telescopic catheter body eliminates any need for placing an additional motorized unit on the bedside, thereby improving ease of use and reducing catheter manufacturing costs. In various embodiments, a flush-free catheter is provided with improved sealing coupling medium reliability, preventing leakage and air ingress. In some embodiments, intracavitary ultrasound imaging is achieved using the apparatus and methods described herein. Imaging and diagnosis of intracavitary tissues (e.g., intravascular, body cavity, digestive tract, esophagus, stomach, intestine, rectum, pancreas, sinuses, ureter, bladder, gynecological, etc.) helps identify irregularities, diseases, and / or injuries for medical treatment, thereby improving patient outcomes in some embodiments.

[0038] In various embodiments, a pre-filled IVUS device is provided, comprising one or more seals that help prevent leakage of the acoustic coupling medium from the device. For example, a flexible seal can compensate for pressure differences present during lumen filling or during varying pressures and temperatures during transport, handling, and storage. In various embodiments, a flush-free IVUS conduit includes an imaging core containing a rotating ultrasonic transducer connected to a distal end of a drive shaft. The drive shaft may optionally include a drive cable, a drive coil, a transmission system, and / or a drive actuator. The IVUS conduit may include a flexible elongated member containing a sealed lumen designed to accommodate the rotating ultrasonic transducer and the acoustic coupling medium. The sealed lumen may include a proximal end, a distal end, and a flexible wall extending 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. The IVUS conduit may include a rigid connector hub with an internal chamber, a media filling port, a distal interface, a proximal interface, and a flexible seal. The medium filling port may optionally be designed to insert the acoustic coupling medium into the rigid connector hub to fill the sealing cavity. The distal interface may be configured to connect to a proximal connector strain relief device of the sealing cavity. Optionally, the proximal interface may be configured to connect to a console that rotates the drive shaft. In some embodiments, the imaging console is a tablet computer, workstation, computer, monitor, user interface, or other control device that may contain a processor and / or software. In some embodiments, the seal is distally connected to a sealing housing connected to the proximal interface, wherein the seal is proximally connected to the internal chamber of the rigid connector hub; wherein the drive shaft extends distally through the seal, and wherein the sealing cavity is in sealing medium communication with the seal, the internal chamber, and the distal plug.

[0039] In some embodiments, an ultrasonic catheter is provided, including one or more seals that allow air to escape while allowing the acoustic coupling medium to completely fill a cavity surrounding the ultrasonic transducer to reduce or eliminate air bubbles (which thus provide a clearer image, as air bubbles can interfere with the transmission of sound waves). In one embodiment, a device (including, but not limited to, a flush-free IVUS catheter) is provided, including an ultrasonic transducer connected to a drive shaft, an elongated member including at least one sealed lumen, wherein the sealed lumen is configured to receive the ultrasonic transducer and the acoustic coupling medium, wherein the sealed lumen includes a proximal end, a distal end, and one or more walls extending a length between the proximal and distal ends. Optionally, the proximal end includes a proximal connector; wherein the distal end includes one or more distal ports and one or more distal plugs. A rigid connector hub may optionally include one or more internal chambers, one or more media filling ports, one or more distal interfaces, one or more proximal interfaces, and one or more seals. The media filling ports are configured to insert the acoustic coupling medium into the rigid connector hub to fill the sealed lumen. The distal interfaces are configured to connect to the proximal end of the elongated member and the sealed lumen. In one embodiment, the proximal interface may be configured to connect to a console, wherein the console is configured to actuate a drive shaft, and a seal is distally connected to a sealing housing connected to the proximal interface. According to one embodiment, the seal may proximally connect to an internal chamber of a rigid connector hub, while the drive shaft extends distally through the seal, and a sealing lumen is in sealing medium communication with the one or more seals, the one or more internal chambers, and the one or more distal plugs.

[0040] In various embodiments, the conduit includes an ultrasonic transducer connected to a drive cable, an elongated member including a lumen, wherein the lumen is configured to receive the ultrasonic transducer and an acoustic coupling medium, wherein the lumen includes a proximal end, a distal end, and a wall extending a length between the proximal and distal ends, wherein the proximal end includes a proximal connector; wherein the distal end includes a distal port and a distal plug; a rigid connector hub including an internal chamber, a distal interface, a proximal interface, and a seal, wherein the distal interface is configured to connect to a proximal connector strain relief device of the lumen; wherein the seal is distally connected to a sealing shell connected to the proximal interface, wherein the seal is proximally connected to the internal chamber of the rigid connector hub; wherein the drive cable extends distally through the seal, wherein the lumen is in communication with the seal, the internal chamber, and the distal plug in a sealing medium.

[0041] Optionally, the sealing shell is coupled to the connector hub, for example, via a sealing port. The flush-free IVUS conduit may also include a second sealing shell attached to the proximal interface. In one embodiment, the media filling port is configured to seal after delivery of the acoustic coupling medium. The distal plug may optionally include a detachable wire extending through the distal port, configured to be inserted into the proximal end of the lumen and pulled to the distal end of the lumen via the detachable wire, coupled to the distal port, coupled to a portion of the flexible wall near the distal end, and configured to seal using the distal plug, which may be coupled by heating and / or adhesive. The distal plug may be a polymer. Optionally, the coupling medium is selected from one or more of the following groups: polyethylene glycol (PEG), water, saline, glycerin, and oil (and combinations thereof). The drive shaft may be rotary actuated by an actuator near the proximal interface. Optionally, the imaging core may be electrically communicated with the console via the drive shaft. For example, the console may include a processor configured to instruct the actuator to rotate the imaging core, instruct the rotating transducer to generate an ultrasound signal, receive a backscattered signal from the rotating transducer, and / or generate an ultrasound image based on the backscattered signal.

[0042] In various embodiments, a kit is provided that includes one, several, or all of the following conduits, hubs, connectors described herein, and an instruction manual.

[0043] In some embodiments, artificial intelligence and / or machine learning (AI / ML) are employed to achieve and / or enhance image interpretation using the techniques described herein. In one embodiment, the system uses acoustic and signal processing techniques tailored for peripheral vascular imaging with enhanced resolution and / or penetration to match high-definition (e.g., HD, UHD, HD+, etc.) image quality. Some embodiments are configured for intravascular imaging, with platforms optimized for peripheral and / or coronary vascular procedures, which will improve image interpretation, interventional guidance, and enhance usability and overall availability to streamline intraoperative and clinical workflows. In some embodiments, the system leverages modern systems with AI tuned to streamline workflows and image interpretation, simplifying user interfaces. In some embodiments, the systems described herein, including, for example, advanced intravascular ultrasound platforms, utilize artificial intelligence (AI) to achieve image interpretation, enhance system-wide capabilities, and streamline workflows to maximize clinical value. In some embodiments, advantageously, physicians will not need to integrate (e.g., cognitive integration) image data spatially and temporally to comprehensively interpret clinical conditions. Instead, systems according to some embodiments described herein can leverage the power of AI with generational advancements to go beyond single image interpretation. In some embodiments, for example, the AI-powered engine may include a workstation that enhances image interpretation through a streamlined workflow, thereby improving overall usability. In some embodiments, machine learning is used. In one embodiment, AI-ready processing capabilities are designed to support real-time and on-demand image interpretation. The AI-powered workstation can provide high-end processing as well as an AI engine for advanced signal and image processing. In various embodiments, native image data capture provides superior image interpretation (e.g., boundary detection, identification and measurement of vessel size, vascular disease, anatomy, plaque morphology, etc.). In some embodiments, the system described herein provides simplified measurements through automatic boundary detection (e.g., AI algorithms automatically identify the boundaries of lumens, vessels, tissues, lesions, plaques, etc.). In some embodiments, the system provides simplified measurements through semi-automatic boundary detection (e.g., the user can manually adjust or modify an automatic AI algorithm that identifies the boundaries of lumens, vessels, tissues, lesions, plaques, etc., with boundary selection reconfigured based on user modifications). In one embodiment, AI plaque identification utilizes AI algorithms to automatically classify and type-identify plaque types within the imaging area, thereby providing user guidance on treatment options (e.g., color coding, icons, or text overlays can be used to indicate what type of condition, such as plaque, might be present in the selected image).In some embodiments, the data-driven platform is designed to collect data and streamline image interpretation, wherein AI processing capabilities support real-time and on-demand image interpretation and reduce the cognitive load on users to help (i) identify lumen size, (ii) visualize anatomy, (iii) characterize disease morphology, (iv) locate and quantify stenosis, and / or (v) identify the actual lumen. In some embodiments, image interpretation is used to identify thrombi, thrombosis, blood clots, embolisms, plaques, calcification, tissue health, stent or balloon alignment, and / or the “health” or condition of the stent or balloon. Image interpretation may involve imaging to assess the quality and / or placement of existing stents. Image interpretation may involve identifying the location relative to the lumen wall and determining the level and / or quality of tissue growth within and around the stent or balloon. In one embodiment, such as for a bioresorbable scaffold, image interpretation may involve: (i) assessing the amount of scaffold dissolution, and (ii) determining whether the scaffold dissolution conforms to the expected attenuation pattern (e.g., determining whether the attenuation on one side of the scaffold is similar to the attenuation on the other side, and if not, this may indicate a problem with scaffold placement, or if the scaffold dissolves faster than expected, this may indicate that the scaffold is failing to provide the expected structural support to the tissue). In one embodiment, high-fidelity ultrasound data is used to improve image generation and interpretation, and artificial intelligence and / or machine learning may be optionally utilized. In various embodiments, catheters, devices, systems, and methods may be configured to perform image-related edge-based machine learning computations and / or image analysis using artificial intelligence algorithms to identify one or more of tissue boundaries, plaques, calcium deposits, thrombi, dissections, and / or scaffold apposition.

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

[0045] In various embodiments, a method of filling an IVUS catheter with an acoustic coupling medium includes: connecting an acoustic coupling medium source to the IVUS catheter, wherein the IVUS catheter includes a flexible elongated member and a rigid connector hub, wherein the rigid connector hub includes an inlet port and an internal chamber, wherein the flexible elongated member includes a lumen, an ultrasound imaging core, and an outlet port; filling the lumen with the acoustic coupling medium through the inlet port; extruding a portion of the acoustic coupling medium through the outlet port; sealing the outlet port with a plug; and sealing the inlet port.

[0046] Optionally, the method may include degassing the acoustic coupling medium. For example, the lumen may be filled with the acoustic coupling medium, including pushing the medium into the lumen under positive pressure at the inlet port, such as, for example, using a peristaltic pump designed to push the medium into the lumen under positive pressure at the inlet port. Optionally, the lumen may be filled with the acoustic coupling medium, including pulling it into the lumen under vacuum pressure at the outlet port. The acoustic coupling medium may be biocompatible, sterilizable, and / or acoustically compatible.

[0047] In various embodiments, a method of filling an IVUS catheter with an acoustic coupling medium includes: providing an IVUS catheter, wherein the IVUS catheter includes a flexible elongated member and a rigid connector hub, wherein the rigid connector hub includes an inlet port and an internal chamber, wherein the flexible elongated member includes an internal lumen, an ultrasound imaging core, and an outlet port; filling the internal lumen with an acoustic coupling medium through the inlet port; extruding a portion of the acoustic coupling medium through the outlet port; sealing the outlet port with a plug; and sealing the inlet port.

[0048] In various embodiments, a method of filling an IVUS catheter with an acoustic coupling medium includes connecting an acoustic coupling medium source to the IVUS catheter, wherein the IVUS catheter includes a flexible elongated member and a rigid connector hub, wherein the rigid connector hub includes an inlet port and an internal chamber, wherein the flexible elongated member includes 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.

[0049] In various embodiments, the unflushed 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 send and receive ultrasound pulses. According to some embodiments, the IVUS catheter may include one or more strain relief components configured to prevent IVUS catheter kinking and excessive localized strain.

[0050] Optionally, the non-flushing IVUS conduit may include: (i) a fill port cap configured to seal the acoustic coupling medium into the sealed imaging lumen at the acoustic coupling medium fill port; (ii) a fill port valve cap, wherein the fill port valve cap includes an open configuration for filling the acoustic coupling medium, wherein the fill port valve cap includes a configuration for sealing the acoustic coupling medium into the sealed imaging lumen at the acoustic coupling medium fill port; and / or (iii) a fill mask configured to insert into and seal the fill port cap or the fill port valve cap. In one embodiment, the rigid connector hub includes a drive bushing disposed around a drive shaft. In some embodiments, the drive shaft may include one or more orifices configured to allow the acoustic coupling medium and air bubbles to flow through the drive shaft.

[0051] In some embodiments, the non-flushing intravascular ultrasound (IVUS) catheter includes (i) an imaging core including a rotating ultrasound transducer connected to a drive shaft; (ii) a flexible elongated member including a sealed imaging lumen, wherein the sealed imaging lumen is configured to receive the imaging core having the rotating ultrasound transducer and an acoustic coupling medium, wherein the sealed imaging lumen includes a proximal end, a distal end, and a flexible wall extending a length between the proximal and distal ends, wherein the distal end includes a distal port and a distal plug; and (iii) a rigid connector hub including an internal lumen, an acoustic coupling medium filling port, a distal interface, a proximal interface, and a flexible seal, wherein the acoustic coupling medium filling port... It is configured to insert an acoustic coupling medium into a rigid connector hub to fill a sealed imaging lumen; wherein a distal interface is configured to connect to the proximal end of the sealed imaging lumen; wherein the proximal interface is configured to connect to a catheter interface module, wherein the catheter interface module includes a motor and an electrical connection to a console, wherein the console is configured to control the rotational actuation of a drive shaft, wherein a flexible seal is distally connected to a sealing housing connected to the proximal interface, wherein the flexible seal is proximally connected to an internal chamber of the rigid connector hub; wherein the drive shaft extends distally through the flexible seal, wherein the sealed imaging lumen is in communication with the flexible seal, the internal lumen, and the distal plug in the sealed acoustic coupling medium.

[0052] In some embodiments, a method of filling an ultrasonic device with an acoustic coupling medium includes: (i) connecting an acoustic coupling medium source to the ultrasonic device, wherein the ultrasonic device includes a flexible elongated member and a rigid connector hub, wherein the rigid connector hub includes an inlet port and an internal cavity, wherein the flexible elongated member includes an internal lumen and an ultrasonic imaging core; and (ii) filling the internal lumen with the acoustic coupling medium through the inlet port; and sealing the inlet port. In various embodiments, the method may include maintaining the acoustic coupling medium in the ambient environment for a first time 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 include maintaining the acoustic coupling medium in a vacuum environment for a second time period (e.g., between about 30 minutes and about 120 minutes) to form a degassed acoustic coupling medium and / or until the acoustic coupling medium reaches a desaturation threshold. In various embodiments, the desaturation threshold is based on an air saturation threshold, between about 5% or less of the air saturation threshold and about 50% or less of the air saturation threshold, and / or about 20% or less of the air saturation threshold. According to some embodiments, the method may include placing an IVUS catheter in a catheter heating plate and heating it to a target catheter temperature between 35°C and 80°C, and / or placing an acoustic coupling medium in a syringe and injecting the acoustic coupling medium into the internal lumen via an injection pump device. The injection pump device may include an injection pump configured to expel the acoustic coupling medium from the syringe at a target delivery rate, such as 0.1 mL / min to 1.0 mL / min.

[0053] The injection pump device may include a rotary motor configured to (i) rotate the imaging core to agitate and remove air from the sealed internal imaging lumen, and (ii) operate at a target speed (e.g., between 900 and 1100 rpm) based on one or more of the following: the internal pressure of the injection pump device and the internal pressure of the sealed internal lumen; and / or the target speed may be adjusted based on one or more of the following: the internal pressure of the injection pump device exceeds a pressure threshold (e.g., between 50 psi and 150 psi), or the internal pressure of the sealed internal lumen exceeds a threshold.

[0054] 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 reservoir configured to receive degassed acoustic coupling medium, wherein the acoustic coupling medium is held in the container in the surrounding environment for a first time period, and wherein the vacuum pump is arranged in fluid communication with the container and configured to hold the container under vacuum pressure for a second time period to convert the acoustic coupling medium into degassed acoustic coupling medium. Optionally, (i) the first time period is between 30 minutes and 300 minutes, (ii) the first time period continues until the acoustic coupling medium reaches an air saturation threshold, (iii) the second time period is between 30 minutes and 120 minutes, (iv) the second time period continues until the acoustic coupling medium reaches a desaturation threshold, (v) the desaturation threshold is based on the air saturation threshold, (vi) the desaturation threshold is between about 5% or less of the air saturation threshold and about 50% or less of the air saturation threshold, (vii) the desaturation threshold is about 20% or less of the air saturation threshold, (viii) the hot plate includes a magnetic stirring mechanism configured to rotate a magnetic stirring rod, (ix) the magnetic stirring rod is placed in the acoustic coupling medium during one or more of the first and second time periods, and wherein the magnetic stirring mechanism is configured to generate a magnetic field to rotate the magnetic stirring rod and stir the acoustic coupling medium, (x) the hot plate is configured to heat the acoustic coupling medium to a first target temperature during the first time period, and / or (xi) the hot plate is configured to heat the acoustic coupling medium to a second target temperature during the second time period.

[0055] In some embodiments, the catheter heating device includes: an insulating layer; a heating layer disposed above the insulating layer, the heating layer being configured to heat the IVUS catheter to a target temperature; a catheter receiving layer disposed above a heating element, the catheter receiving layer including a catheter incision configured to receive the IVUS catheter; and a covering layer disposed above the catheter receiving layer. The catheter heating device may optionally include: (i) a target temperature between at least about 35°C and at least about 80°C; (ii) a catheter incision shape that is one of an "S", a spiral, or a straight line; (iii) a catheter incision shape based on one or more properties of the IVUS catheter; (iv) a catheter receiving layer comprising one of a metal, a metal alloy, and a metal composite; (v) a catheter receiving layer comprising a metal, such as aluminum; and / or (vi) a heating element comprising one or more heating elements.

[0056] In some embodiments, the flush-free intravascular ultrasound (IVUS) catheter includes (i) an imaging core comprising a rotating ultrasound transducer disposed in a transducer housing connected via a coupler to a distal end of a drive shaft and a coil; (ii) a flexible elongated member comprising a sealed imaging lumen configured to receive the rotating ultrasound transducer and an acoustic coupling medium, wherein the sealed imaging lumen includes a proximal end, a distal end, and a flexible wall extending a length between the proximal and distal ends, wherein the distal end includes a distal port and a distal plug; (iii) a rigid connector hub comprising an internal chamber, an acoustic coupling medium filling port, a distal interface, a proximal interface, and a flexible seal; and (iv) one or more orifices disposed on one or more of the transducer housing, the coupler, and the drive shaft, the orifices being configured to allow the acoustic coupling medium to pass through. A mass and air bubbles flow through one or more of a transducer housing, a coupler, a coil, and a drive shaft; wherein an acoustic coupling medium filling port is configured to insert acoustic coupling medium into a rigid connector hub to fill a sealed imaging lumen; wherein a proximal interface is configured to connect to a control console, wherein the control console is configured to control rotational actuation of the drive shaft; wherein the proximal interface is configured to connect to a catheter interface module, wherein the catheter interface module is configured to rotate the drive shaft via an actuator; wherein the catheter interface module includes a transceiver configured to send and receive ultrasound pulses; wherein a flexible seal is distally connected to a sealing housing connected to the proximal interface; wherein the flexible seal is proximally connected to an internal chamber of the rigid connector hub; wherein the drive shaft extends distally through the flexible seal; wherein the sealed imaging lumen is in communication with the flexible seal, the internal chamber, and the distal plug in a sealed acoustic coupling medium.

[0057] In general, some embodiments described herein provide an ultrasound transducer suitable for acoustic imaging within a blood vessel via a catheter. Images and / or measurements of the vascular anatomy at the treatment site can be created by probing the surrounding blood and tissue using ultrasound pulses generated by the ultrasound transducer and by creating images of the blood and tissue based on the backscattered signals in response to the ultrasound pulses. The ultrasound pulses can be acoustically transmitted through an acoustic coupling medium, a catheter polymer sheath, traveling through the blood and tissue and continuously backscattering back to the transducer, then returning through the catheter sheath and coupling medium, and finally being received by the transducer. Specifically, intravascular ultrasound imaging can create a 360° cross-sectional image of blood and tissue from within the vascular system based on the backscattered acoustic signals in response to the ultrasound pulses.

[0058] According to some embodiments, the systems and methods described herein are designed to create improved intravascular ultrasound imaging. More specifically, in some embodiments, the systems and methods described herein generate intravascular ultrasound images in which image quality is not degraded by air bubbles by incorporating an encapsulated acoustic coupling medium. In some embodiments, the IVUS catheter reduces or eliminates the need for the user to flush the imaging core with fluid, which requires valuable surgical time to ensure reduction, removal, or elimination of air bubbles in 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 of fixed length and have a rotating imaging core with a sealed encapsulated acoustic coupling medium. In some embodiments, the coupling medium is a fluid, liquid, and / or gel. In some embodiments, liquid coupling media are easier to fill the lumen and minimize air bubbles. In some embodiments, the IVUS catheter does not require a telescopic portion connected to a motorized unit to enable imaging of the vascular system using a rotating imaging core. Methods for reliably filling the coupling medium, which can support imaging without being hindered by air, are also disclosed.

[0059] In various embodiments, the IVUS catheter includes a rotating and / or translating imaging core assembly located within a polymer sheath. The transducer can translate and / or rotate within the distal lumen of the catheter sheath, and in one embodiment, a coupling medium, such as a liquid or gel, supports the transducer in transmitting and receiving ultrasound pulses. Without a coupling medium, air may be present between the transducer and the catheter sheath, inhibiting sufficient energy transmission into the patient's blood vessels, which could result in poor image quality.

[0060] In various embodiments, IVUS uses ultrasound only for imaging (without treatment). In various embodiments, IVUS uses ultrasound only for treatment (without imaging). In various embodiments, IVUS uses ultrasound for both imaging and treatment. According to some embodiments, one or more imaging techniques described herein may be combined with one or more treatment elements on the same catheter, such as an integrated ultrasound imaging element located at or near the end of a thrombectomy device (or additionally along the thrombectomy device). The thrombectomy device may also be a separate device delivered before, during, or after the delivery of the imaging device. The thrombectomy device may be a mechanical clot removal device, a clot aspiration device, or a combination of clot removal and aspiration. In some embodiments, the ultrasound imaging devices and methods disclosed herein, along with (integrated or separate) clot treatment devices, are used to treat neurovascular, coronary, and pulmonary clots. Clot treatment devices may also include, for example, non-mechanical devices, such as dissolving devices or other drug delivery devices, and energy delivery devices for disrupting / removing clots or otherwise restoring blood flow. Combinations of two, three, or more therapies with the IVUS imaging techniques described herein are also provided (e.g., ultrasound or laser clot destruction using a dissolving agent). According to some embodiments, integrated blood IVUS and treatment catheters or probes can also be used to restore blood flow not caused by clots.

[0061] In various embodiments, the IVUS catheter is configured to image tissue and / or plaque (e.g., one or more of hard plaques, soft plaques, vulnerable plaques, calcified plaques, and essentially non-calcified plaques) (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, calcification severity, vascular measurement, and / or pre- and post-operative planning. In some embodiments, the techniques described herein can be used to guide stent sizing design, determine stent placement, alignment, and / or dilation, assess lesion morphology, vessel wall thickening, loss of luminal patency, and / or vascular dysfunction, quantify plaque burden, identify complications arising from surgery, and / or assess stent failure regarding in-stent thrombosis or in-stent restenosis. The techniques described herein can differentiate between lipids, calcified plaques, and tissue hyperplasia. In many embodiments, superior imaging detail is provided compared to, for example, angiography techniques.

[0062] As summarized above and described below, when an apparatus or method "comprises" or "includes" (the two are interchangeable) certain features or steps, if so indicated, such an apparatus or method may also "…". Consisting Essentially Of Some of those features or steps Figure 1A (That is, the claims state "consistent with...").

[0063] The techniques described herein are used in some embodiments to focus intraluminal images using a rotating single-element ultrasound transducer by modifying the image (e.g., angular diffraction, phase, amplitude, time shift, synthetic backscatter reflection image), including the techniques described in U.S. Patent No. 63 / 497,962 entitled "Spinning Single Element Ultrasound Transducer and Focusing Methods" (and a PCT application claiming priority thereto, filed April 11, 2024); manual assisted pullback, voice control, and position sensors (e.g., encoders) for spatial alignment measurements, including systems and methods of manually assisted pullback for spatial alignment lengthwise measurements in Intravascular Ultrasound. The technologies described in U.S. Patent No. 63 / 531,266, entitled “Imaging”, and ultrasound imaging systems and components, voice control, and artificial intelligence algorithms, including the technologies described in U.S. Patent No. 63 / 546,058 entitled “Systems and Methods for Intravascular Ultrasound”, all of which are incorporated herein by reference in their entirety. Attached Figure Description

[0064] The following figures are for illustrative purposes only and illustrate non-limiting embodiments. Features from different figures may be combined in some embodiments.

[0065] Figure 1B This is a block diagram of a rotating intravascular ultrasound system according to an embodiment.

[0066] Figure 2A This is a block diagram of a rotating intravascular ultrasound system with a catheter interface module according to an embodiment.

[0067] Figure 2B Details of the distal end of an imaging catheter with an elongated member, including a rapid exchange (RX) lumen, are shown according to an embodiment.

[0068] Figure 3A Details of the distal end of an imaging catheter with an elongated member, including an over-the-wire (OTW) lumen, are shown according to an embodiment.

[0069] Figure 3B This is an isometric view of the connector hub of the IVUS conduit system according to an embodiment.

[0070] Figure 3A According to the embodiments Figure 4 The side sectional view of the connector hub shown.

[0071] Figure 5 This is a side cross-sectional view of the distal end of an elongated member according to an embodiment, the elongated member including a lumen having a distal port.

[0072] Figure 6 An example procedure for filling an unflushed intravascular ultrasound catheter according to an embodiment is described.

[0073] Figure 7 Another example procedure for filling an unflushed intravascular ultrasound catheter is shown according to an embodiment.

[0074] Figure 8 An example procedure for filling an unflushed intravascular ultrasound catheter according to an embodiment is described.

[0075] Figure 9 An intravascular ultrasound system including a catheter is shown according to an embodiment.

[0076] Figure 10 A sub-component of an intravascular ultrasound system including a catheter is shown according to an embodiment.

[0077] Figure 11 An imaging core according to an embodiment is shown.

[0078] Figure 12 The distal end of the catheter according to an embodiment is shown.

[0079] Figure 13 A photographic description of one embodiment of the distal end is shown.

[0080] Figure 14 An intravascular ultrasound system including a catheter is shown according to an embodiment.

[0081] Figure 15 A sub-component of an intravascular ultrasound system including a catheter is shown according to an embodiment.

[0082] Figure 16 A catheter sheath according to an embodiment is shown.

[0083] Figure 17 The distal end according to an embodiment is shown.

[0084] Figure 18 A cross-sectional view of the catheter sheath according to an embodiment is shown, depicting the guidewire lumen and the imaging lumen.

[0085] Figure 19 The center hub and proximal sleeve according to an embodiment are shown.

[0086] Figure 20 The proximal hub according to an embodiment is shown.

[0087] Figure 21 An isometric view of the distal end with an acoustic coupling medium is shown according to various embodiments.

[0088] Figure 22 The proximal hub assembly process according to an embodiment is shown.

[0089] Figure 23A The media filling process according to an embodiment is shown.

[0090] Figure 23B An exploded view of the proximal hub assembly according to an embodiment is shown.

[0091] Figure 24A A cross-sectional view of the proximal hub assembly according to an embodiment is shown.

[0092] Figure 24B A cross-sectional view of a proximal hub with a strain relief assembly according to an embodiment is shown.

[0093] Figure 24C An isometric view of the proximal hub with strain relief components according to an embodiment is shown.

[0094] Figure 25A An isometric view of the proximal hub with strain relief components according to an embodiment is shown.

[0095] Figure 25B A cross-sectional view of the proximal hub and filling nozzle according to an embodiment is shown.

[0096] Figure 26A A cross-sectional view of a proximal hub and a filling nozzle according to an embodiment is shown, the proximal hub and the filling nozzle being engaged to fill the proximal hub using a coupling medium.

[0097] Figure 26B The medium filling port of the proximal hub in the open position according to an embodiment is shown.

[0098] Figure 26C A medium filling port of a proximal hub that engages with a filling nozzle, according to an embodiment, is shown.

[0099] Figure 26D The medium filling port of the proximal hub is shown according to an embodiment when the proximal hub is disengaged from the filling nozzle.

[0100] Figure 27The medium filling port of the proximal hub connector in the closed or sealed position according to an embodiment is shown.

[0101] Figure 28A An apparatus for degassing a coupling medium according to an embodiment is shown.

[0102] Figure 28B An apparatus for heating a coupling medium according to an embodiment is shown.

[0103] Figure 29A An injection pump device for heating coupling medium according to an embodiment is shown.

[0104] Figure 29B An isometric view of the conduit heating plate according to an embodiment is shown.

[0105] Figure 30 A side view of the conduit heating plate according to an embodiment is shown.

[0106] Figure 30A A side view of the imaging core of an IVUS catheter according to an embodiment is shown.

[0107] Figure 30 A cross-sectional view of the proximal portion of the transducer housing is shown, illustrating the relationship between the transducer housing and the transducer housing. Figure 31 The aperture of the embodiment shown.

[0108] Figure 32 A side view of the proximal hub of an IVUS catheter according to an embodiment is shown.

[0109] Figure 33 A cross-sectional view of the IVUS catheter shaft according to an embodiment is shown.

[0110] Figure 34 The flow of the acoustic coupling medium through the imaging lumen of the IVUS catheter according to an embodiment is illustrated.

[0111] Figure 1A This is the process of degassing the acoustic coupling medium and filling the IVUS conduit according to the embodiment. Detailed Implementation

[0112] According to some embodiments, the systems and methods described herein are directed to an improved intravascular ultrasound imaging system. According to some embodiments, the IVUS catheter includes a rotating imaging core located within a sealed imaging lumen, which encapsulates an acoustic coupling medium, for example configured to reduce or eliminate the need for the user to flush the imaging core before and during use. In various embodiments, methods for reliably filling the lumen of an unflushed catheter with a coupling medium that supports imaging in the absence of air within the encapsulated coupling medium are disclosed. In one embodiment, several methods for reducing or eliminating air bubbles within the sealed lumen are disclosed. The methods disclosed herein may include filling and encapsulating the coupling medium within the lumen to eliminate leakage and ensure that air bubbles do not interfere with the delivery of high-quality images.

[0113] Some embodiments described herein provide an IVUS catheter with a proximal connector hub assembly that facilitates the process of filling the IVUS catheter imaging lumen with an acoustic coupling medium during catheter manufacturing. This coupling medium can encapsulate the imaging transducer, thereby forming an imaging pathway unobstructed by air bubbles.

[0114] In some embodiments, the proximal connector hub assembly may include a proximal connector hub with a filling port, a filling port cap, and a filling mask. The filling port may receive the filling port cap, which may include a resilient seal or a rigid plastic cap. The filling port cap may cooperate with a filling adapter of a filling nozzle, which may be used to fill the imaging lumen of the IVUS catheter with acoustic coupling medium. In one embodiment, if the filling port cap is a resilient seal, the filling nozzle may include a needle that pierces the seal to fill the catheter. When the IVUS catheter has been filled, the filling nozzle and the filling port adapter may disengage from the filling port cap, and then the filling port cap may be covered by the filling mask. When the IVUS catheter has been filled, the disengagement of the filling nozzle and the filling port adapter from the filling port cap may draw the acoustic coupling medium into the filling port cap and prevent air from entering the imaging lumen of the IVUS catheter. In some embodiments, the proximal connector hub assembly may include a proximal connector hub with a filling port, a filling port valve cap, and a filling mask. The filling port may receive the filling port valve cap. The fill port valve cap mates with the fill adapter of the fill nozzle, which is used to fill the IVUS catheter with acoustic coupling medium. When the IVUS catheter has been filled, the fill nozzle and fill port adapter can be disengaged from the fill port valve cap, which draws the acoustic coupling medium into the fill port valve cap and prevents air from entering the imaging lumen of the IVUS catheter.

[0115] In some embodiments, the proximal connector hub may include a strain relief assembly that reduces or prevents kinking and excessive localized strain in the IVUS conduit. According to some embodiments, the proximal hub connector may also include a seal, a drive bushing, a drive hub, a drive pin, and / or an electronic identification (EID) printed circuit board (PCB). The drive bushing reduces wobbling and / or non-uniform rotational deformation (NURD) and prevents acoustic coupling fluid leakage by maintaining uniform friction around the inner diameter of the seal.

[0116] The methods described herein provide a way to degas the acoustic coupling medium and fill the IVUS catheter with the degassed medium. Pre-filling the catheter with the acoustic coupling medium during manufacturing can optionally and advantageously eliminate the need for user preparation and fluid flushing of the lumen surrounding the internal imaging core. In some embodiments, degassing the acoustic coupling medium has the advantage of reducing the dissolved air content in the medium, so that any small amount of air remaining in or introduced into the catheter during the manufacturing process or during the device's shelf life 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 medium during filling, which improves the image quality captured by the IVUS catheter and reduces procedure time by eliminating the need for refilling or replacing the IVUS catheter, among other advantages described herein.

[0117] In some embodiments, the degassing process includes subjecting the acoustic coupling medium to a vacuum (or low) pressure for a period of time. In one embodiment, the degassing process may begin by providing a degassing device. This 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 conduit and a first valve, such as a diverter valve. The container may be connected to the syringe via a second valve, such as a stopcock valve. The acoustic coupling medium may be placed in the container for a first time period. The first time period may be a predetermined time period or may continue until the acoustic coupling medium reaches an air saturation threshold. After the first time period, the acoustic coupling medium may be exposed to vacuum pressure for a second time period. The second time period may be a predetermined time period as described below or may continue until the acoustic coupling medium reaches a desaturation threshold. Once the acoustic coupling medium reaches the desaturation threshold, the medium may be transferred to the syringe (e.g., via a conduit 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 fluid viscosity, thereby facilitating a subsequent filling process.

[0118] According to some embodiments, the techniques described herein, such as IVUS no-rinse technology, include reversible rinse port seals that allow for rework of the product after inspection (e.g., checking image quality if air bubbles remain, etc.) and before optionally permanent sealing. In some embodiments, the filling and / or rinsing process can be repeated using one or more reversible port seals until a satisfactory result is achieved (e.g., air bubbles are removed, etc.). In one embodiment, the seal is reversible. In one embodiment, the seal is permanent. In some embodiments, the fill port may be temporarily sealed to facilitate inspection and permanently sealed after confirmation of successful filling. In some embodiments, the temporary seal of the fill port may be removed to facilitate further fluid filling process steps.

[0119] An IVUS catheter can be filled using a degassed acoustic coupling medium. In some embodiments, the filling process can be initiated by providing an IVUS catheter filling device and pressurizing the medium, such as using an injection pump device or other fluid pump device. The filling device may also include a means of heating the catheter during the filling process, such as using a heating plate and / or a microscope to monitor the filling process and inspect for air bubbles. The IVUS catheter may be placed in a catheter heating plate and heated to a target catheter temperature. The catheter heating plate may include a cut for receiving the IVUS catheter. The cut may be S-shaped, spiral-shaped, a straight path, etc., and may be shaped based on one or more properties of the IVUS catheter.

[0120] The syringe pump device can receive a syringe containing degassed acoustic coupling medium. The syringe pump device may include a syringe pump, a syringe heating assembly (e.g., a syringe sleeve), a pressure gauge, at least one piece of tubing, a pump, and / or a three-way valve. The syringe pump can receive the syringe, and the syringe heating assembly can be positioned around the syringe and heat the syringe to a target temperature, for example, 60°C. The syringe pump can expel the acoustic coupling medium from the syringe through the pressure gauge and into the tubing. In some embodiments, the syringe pump can expel the acoustic coupling medium at a target delivery rate, for example, 0.4 mL / min. This delivery rate can be adjusted based on whether the pressure in the syringe pump device or the IVUS tubing exceeds a pressure threshold, for example, 80 psi. In some embodiments, the syringe pump can expel the acoustic coupling medium at a target fill pressure.

[0121] Acoustic coupling medium can be delivered to the pump via a valve, such as a three-way valve, through conduit. 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 push the acoustic coupling medium from the conduit and / or syringe to the proximal connector hub of the IVUS catheter to fill the catheter imaging lumen. According to some embodiments, the pump can also expel air from the imaging lumen of the IVUS catheter.

[0122] 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 the imaging core and its surroundings. In various embodiments, the rotation speed is 500–2000 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. For example, in one embodiment, if bubbles adhere to the inner wall of the imaging lumen at higher speeds, the target speed may be temporarily reduced to facilitate distal movement of the bubbles, and the speed may subsequently be increased again to shorten the total filling time.

[0123] Several embodiments described herein provide an IVUS conduit having one or more features that allow for easier filling of the acoustic coupling medium while minimizing the risk of air ingress into the medium. The IVUS conduit may include an imaging core disposed within an imaging lumen of the conduit. According to one embodiment, the imaging core may include a wired transducer located within a transducer housing attached to a distal end of a torque coil. 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 disposed within the torque coil, connecting the transducer to a printed circuit board in the proximal connector hub. A coupler assembly may connect the transducer housing to the coil. According to some embodiments, the transducer, transducer housing, and / or coupler may include one or more orifices. According to some embodiments, the drive shaft may also include one or more orifices. The IVUS conduit may include a first lumen gap between the coaxial cable and the torque coil, and a second gap between the torque coil and the inner diameter of the imaging lumen.

[0124] Advantageously, in some embodiments, the difference in cross-sectional area between one or more orifices and / or the first and second gaps within the IVUS catheter can reduce the resistance to media flow during air expulsion from the coil inside the IVUS catheter, increasing the speed and efficiency of IVUS catheter filling and making air bubble removal more effective. This can improve the overall quality of IVUS images captured by the IVUS catheter.

[0125] In some embodiments, imaging clarity is essential for the accurate identification of lesions, plaques (e.g., hard plaques, soft plaques, vulnerable plaques, calcified plaques, largely non-calcified plaques, fibrofatty plaques), thrombi, calcium deposits, dissections, and the measurement of these abnormalities. IVUS imaging can be used to plan treatment and guide therapy selection in systemic interventional cardiology, vascular surgery, and interventional radiology, from the heart to the peripheral vascular system, for example, for measuring lesions and for guiding and evaluating stent implantation. In some embodiments, IVUS catheters are used for arteries, veins, and vessels (e.g., carotid artery, subclavian artery, pulmonary artery, arterial artery, renal artery, iliac artery, arteriovenous (AV) fistula, femoral artery, popliteal artery, tibial artery, etc.). In some embodiments, intraluminal imaging is performed using the devices and methods described herein. Imaging and diagnosing intraluminal tissues (e.g., intravascular, body cavity, digestive tract, esophagus, stomach, intestine, rectum, pancreas, sinuses, ureter, bladder, gynecological, etc.) can help identify abnormalities, diseases, and / or injuries for medical treatment, thereby improving patient outcomes. For example, endoscopes may be used in conjunction with some of the features described herein. Transvaginal ultrasound and other gynecological ultrasound devices may also incorporate some of the features described herein. For embodiments in which EUS (endoscopic ultrasound) and other endocavitary imaging or other body cavity or organ imaging (and such imaging is not intravascular) are performed, the features described herein for “IVUS” or “catheter” should be understood to be applicable to endocavitary (or other cavity / organ) catheters, probes, tubes, endoscopes, and other such devices. In some embodiments, the techniques described herein may be used in conjunction with other medical imaging systems (e.g., cardiac catheterization laboratory systems) to provide physicians, such as cardiologists, with precise healthcare combinations. In some embodiments, collaborative platforms improve workflow between IVUS and one or more other imaging systems (e.g., X-ray systems). In one embodiment, the IVUS techniques described herein are used in conjunction with X-ray, extracorporeal ultrasound, and / or other non-IVUS techniques to optimize stent placement and other procedures.

[0126] This document describes imaging and diagnosis of intravascular or extravascular tissues in some embodiments, including the identification of abnormalities (or irregularities). The term “abnormality” as used herein may be given its general meaning and should also include vascular or other malformations, constriction, occlusion, dilation, disease, and injury. Irregularities may also include lesions, thrombosis, aneurysm, dissection, plaque (e.g., hard plaque, soft plaque, vulnerable plaque, calcified plaque, basally non-calcified plaque, fibrofatty plaque), fistula, tumor, tumor formation, gallstones, kidney stones, polyps, cysts, etc., and morphological assessments of such abnormalities located within blood vessels, other body cavities, or other target sites. In some embodiments, irregularities may also include stent or balloon displacement, dissection (e.g., after atherosclerotic plaque resection, after balloon angioplasty, etc.), identification of the cause of compression, under-dilation of stents or other devices, and issues concerning the sizing and severity grading of abnormalities or stents, such as iliac vein stents, under-dilation under IVUS guidance. Irregularities in the esophagus, stomach, and small intestine can be observed through some of the embodiments described herein (e.g., by endoscopic ultrasound imaging).

[0127] In addition to identifying anomalies, some of the embodiments described herein are used to facilitate related measurements and preparations for the deployment of stents and / or balloons, and can be used by medical practitioners to develop treatment plans.

[0128] After identifying the abnormality, appropriate treatment can be utilized on the patient. For example, image-guided treatment of tumors, thrombi, plaques, etc., can be used, where imaging and treatment functions are present on one or more devices. Some embodiments include, for example, percutaneous coronary intervention for coronary artery lesions, intravascular imaging-guided percutaneous intervention for peripheral vascular lesions, and / or intravascular imaging-guided percutaneous intervention for arteries and / or veins. In some embodiments, the IVUS system is configured for optimized peripheral vascular surgery. In some embodiments, the IVUS system is configured for optimized peripheral vascular surgery, but not for coronary artery surgery. In some embodiments, the IVUS system is configured for coronary artery surgery. In some embodiments, the IVUS system is configured for neurovascular surgery (including but not limited to cerebrovascular surgery). 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 embolism resection. In some embodiments, synchronous, real-time IVUS guidance is provided for procedures such as thrombectomy / embolization, stent placement, clot aspiration, and other coronary or neurovascular surgeries.

[0129] While some embodiments described herein depict IVUS, the techniques described herein are also used for intraluminal imaging (in addition to intravascular and extravascular imaging). For example, some embodiments are used for imaging, diagnosing, and / or providing image-guided interventions of the digestive tract, esophagus, stomach, intestine, rectum, sinuses, ureters, bladder, uterus, fallopian tubes, lungs, brain, etc. The systems and methods described herein can be used in conjunction with endoscopes rather than IVUS catheters and support the identification and diagnosis of gastrointestinal tumors, such as tumors in the intestines and / or bile ducts. Similarly, the systems and methods described herein can be used for imaging sinus cavities using IVUS.

[0130] Figure 1B and Figure 1A An intravascular ultrasound (IVUS) system 100 according to one embodiment is illustrated. In various embodiments, the system 100 is flush-free. In various embodiments, the system 100 includes reusable and / or disposable components. In one embodiment, the disposable component is a series of one or more 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 catheter body 102, a catheter shaft 110, an imaging core 104, a transducer 105, and a proximal connector for attaching to the proximal connector hub 116. In one embodiment, for example... Figure 1B In the illustrated embodiment, the reusable component is the console 118, to which the conduit body 102 is directly attached, for example, via the proximal connector hub 116. The console 118 may include one or more processors 112, one or more transceivers 113, and / or actuators 114. In one embodiment, for example in… Figure 2AIn the illustrated embodiment, a reusable component of system 100 may include a catheter interface module (CIM) 115 disposed between console 118 and catheter 101. Transceiver 113 and actuator 114 may be part of CIM 115, and CIM may be remote from console 118 and attached to console 118 via a cable. According to some embodiments, components of transceiver 113 and actuator 114 may be distributed between console 118 and CIM 115. CIM 115 may be arranged to communicate electronically with console 118. For example, CIM 115 may be connected to console 118 via a cable, and proximal connector hub 116 of catheter 101 may be connected to CIM 115. Intravascular ultrasound system 100 may include catheter 101 with catheter body 102, console 118, and display 120. Display 120 may be part of console 118. Catheter body 102 of catheter 101 may be a flexible, elongated member. The catheter body 102 may be divided into a working length segment that can be inserted into the patient's body and a proximal extension segment that connects the working length to a proximal connector hub 116. The working length segment may be a fixed length that allows the distal catheter imaging portion to be placed from the vascular access point to the treatment point. In some embodiments, the catheter 101 has a proximal extension length configured to attach the proximal connector 116 to a catheter interface module 115 outside a sterile area. 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 (e.g., lengths of 90, 100, 110, 125, 150, 175, 200, 230, 250, 280, 310, 350, 370, or 400 cm, including values ​​therein). In various embodiments, the length of the catheter body 102, including both the working length and proximal extension, can be at least 3 feet (ft), at least 4 feet, at least 5 feet, at least 6 feet, at least 7 feet, at least 8 feet, at least 9 feet, at least 10 feet, at least 11 feet, at least 12 feet, or at least 13 feet. In some embodiments, the length of the catheter body 102 is fixed and may not include any telescopic portions. 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 with 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 layers of material to refract ultrasound signals and / or limit backscattered signals in a desired manner. The catheter body 102 may have one, two, or more connecting elements, such as portions of different 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 be advanced along the guidewire to a target site. In one embodiment, for example... Figure 4 As depicted, the guidewire lumen employs a quick-change (RX) end design, extending along the length of the distal end, with the guidewire exit port located at the proximal end of the distal end. In some embodiments, the distal end includes a distal plug, such as when combined with... Figure 2B As discussed in more detail. In another embodiment, the guidewire lumen extends along the working length of the catheter body 102, as... Figures 3A-3B As depicted in the text.

[0131] In some embodiments, the imaging core 104 includes a drive shaft and a distal transducer 105. In various embodiments, the transducer 105 may be a single-element transducer or a multi-element transducer array. In one embodiment, a single ultrasound transducer (e.g., having only a single element, without multiple elements, without multiple elements, and / or without an element array) is positioned within the intravascular location of the catheter for acoustic imaging. In various embodiments, the multi-element array may be an array of 2, 8, 10, 12, 16, 24, 32, 50, 64, 100, or 128 elements. 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 proximal to distal. 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 of the catheter body 102 to the distal end and terminate before the distal end. In one embodiment, the imaging lumen 108 may extend from the proximal 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 includes a proximal opening and a distal opening. The imaging lumen 108 may be sealable and includes a proximal port and a distal port. The proximal opening of the imaging lumen may be connected to a filling port, such as a filling port in the proximal connector 116. The distal opening may be located distal to or near the imaging lumen 108 and includes a small opening that vents air during the filling process and is then sealed. The proximal and distal openings may be combined as follows. Figure 4 , Figure 5 and Figures 3A-3B The imaging lumen 108 is sealed. It may be sealable and includes a proximal port and a 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 combined as follows. Figure 4 , Figure 5 and Figure 3A The process involves sealing. In various embodiments, the lumen can be an internal lumen (e.g., an imaging lumen). In various embodiments, the wall can be an inner wall or an outer wall. In various embodiments, the transducer can be an internal transducer. In various embodiments, the imaging core 104 can be an internal imaging core 104.

[0132] In some embodiments, the imaging catheter 101 of the system 100 includes a catheter body 102, an imaging core 104, and a proximal connector hub 116. The imaging core 104 has a rotary transducer 105 disposed within an imaging lumen 108. In various embodiments, the rotary transducer 105 is an assembly of the imaging core 104. The rotary transducer 105 may be disposed at a distal portion of the imaging lumen 108 of the catheter body 102 and generates a plurality of ultrasound signals 106. In some embodiments, the rotary transducer 105 may be oriented such that the ultrasound signals propagate perpendicular to the catheter body 102. In some embodiments, the rotary transducer 105 may be oriented such that the ultrasound signals propagate in a circular path perpendicular to the catheter body 102. In some embodiments, the ultrasound signals propagate in a vertical direction away from the catheter body wall, forming a cone shape relative to the catheter wall. The rotary transducer 105 may be oriented such that the ultrasound signals propagate perpendicular to the axis. In various embodiments, the device, such as conduit 101, may include an imaging core 104 comprising a rotating ultrasonic transducer 105 connected to the distal end of a drive shaft 110. The conduit body 102 of conduit 101 may include a flexible elongated member comprising a sealed imaging lumen 108 configured to receive the ultrasonic imaging core 104 and an acoustic coupling medium 109, wherein the sealed lumen includes a proximal end, a distal end, and a flexible wall extending a length between the proximal and distal ends, wherein the proximal end is connected to a filling port of a proximal connector 116, and wherein the distal end includes a distal seal, such as a distal plug. An apparatus may include a rigid connector hub comprising an internal chamber, a media filling port, a distal interface, a proximal interface, and a flexible seal. The media filling port is configured to insert an acoustic coupling medium into the rigid connector hub to fill a sealed lumen. The distal interface is configured to connect to a proximal end of a catheter body 102. The proximal interface is configured to connect to a control console configured for rotational actuation of a drive shaft. The flexible seal is distally connected to a sealing shell connected to the proximal interface. The flexible seal is proximally connected to the chamber of the rigid connector hub. The drive shaft extends distally through the flexible seal. The sealed lumen is in sealing medium communication with the flexible seal, the chamber, and a distal plug of the catheter body 102. Strain eliminators may be positioned at the proximal end of the catheter body 102 and at the distal interface of the proximal connector hub 116 to prevent the flexible catheter body from kinking or excessively bending at its attachment to the rigid proximal connector hub 116. A rotary transducer 105 may also detect multiple backscattered signals. In some embodiments, the conduit 101 of the system 100 may include one, two or more generating transducers and one, two or more receiving transducers.

[0133] In one embodiment, the imaging lumen 108 is configured to receive an imaging core 104, which includes a rotary transducer 105 and a drive shaft 110. The drive shaft 110 optionally mechanically couples the rotary transducer 105 to an assembly in a proximal hub 116, which is in turn connected to an actuator 114 when the catheter is connected to a CIM 115 or a console 118. The imaging lumen 108 may be configured to receive a coupling medium 109. In various embodiments, the coupling medium is biocompatible, sterilizable, and / or acoustically compatible. For example, the coupling medium may be polyethylene glycol (PEG), PEG containing a proportion of water, water, saline, glycerol, and / or oils (e.g., natural oils, mineral oils, etc.) or combinations thereof. In various embodiments, the coupling medium does not contain PEG, water, saline, glycerol, or oil. In various embodiments, the coupling medium is degassed before insertion into the imaging lumen 108. In one embodiment, the coupling medium has a viscosity greater than that of water, which reduces or eliminates nonuniform rotational deformation (NURD). In various embodiments, the acoustic coupling medium may contain a colorant to visually monitor the filling process during the fabrication of the conduit 101, thereby confirming the elimination or reduction of potential air 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%).

[0134] In various embodiments, the proximal connector hub 116 of the imaging conduit 101 of system 100 is configured to connect to actuator 114. Actuator 114 may include components or connections configured to couple conduit assemblies, such as drive shafts, to motors in a console or CIM to induce relative movement between two or more components (e.g., rotational and / or translational movement, rotational and / or translational movement without translational movement) (e.g., movement between rotary transducer 105 and conduit body 102). Actuator 114 may include one, two or more, or a combination thereof of the following: hub, seal, valve, adhesive, bearing, hinge, pin, ball gear, shaft, rotary joint, clutch, disc, gear, belt, motor, linear guide, linear actuator, track, groove, slot, cam, vibration table, etc. The proximal connector hub 116 may include features coupled to features in the actuator 114 such that rotation of the actuator 114 transmits torque to the drive hub 2316, causing the drive hub 2316 to rotate and thereby drive the drive shaft 110 of the imaging core 104. In some embodiments, the actuator is not necessarily coupled to an electronic, motorized, or other automated system, and embodiments of the actuator(s) described herein may be configured to move manually, semi-automatically, and / or automatically. For example, the actuator 114 may be a transmission system or a drive shaft. The actuator 114 may cause the rotary transducer 105 within the catheter body 102 to rotate in an azimuth direction.

[0135] In one embodiment, conduit 101 can be connected via connector hub 116, 300 to one, two or more processors 112 in a console or CIM, the connector hub being in... Figure 3B and Figure 2A The details are shown in more detail below. 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 that enclose the 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 the actuator 114 and the processor 112, which may be housed in a console 118 or CIM 115. According to alternative embodiments, one, two, or more processors may be present.

[0136] In some embodiments, connector hub 116 may also provide proximal rotation of imaging core 104. In one embodiment, a keyed mechanical connection from connector hub 116 to console 118 or CIM 115 provides a tight connection with rotational forces efficiently transmitted from rotary motor actuator 114 to drive shaft 110 of imaging core 104 in catheter 101. In some embodiments, connector hub 116 may maximize torque control of coils of drive shaft 110 in catheter body 102. In some embodiments, connector hub 116 may connect catheter body 102 to console 118, which includes processor 112 and other components. For example, console 118 may include actuator 114, intravascular ultrasound transceiver 113 (which transmits and receives ultrasound pulses), an scalable catheter-specific electrical matching network, and / or a microphone for providing a voice control interface. In some embodiments, actuator and ultrasound transceiver may be housed in CIM, which may be connected to console via cable. In some embodiments, console 118 may include user interface and / or display, including a wireless medical-grade tablet PC that can be docked and recharged between procedures. The tablet may include one or more microphones to provide a voice control interface.

[0137] During treatment, the distal end of catheter 101 may be inserted into the patient's body. Processor 112 can control various elements of system 100 to generate ultrasound images, which can be displayed on display device 120. During treatment, the distal end of catheter 101 may be inserted into a blood vessel in the patient. Processor 112 can control various elements of system 100 to generate ultrasound images of the vessel wall, blood flow, and surrounding tissues, which can be displayed on display device 120. In some embodiments, processor 112 can control the rotation of actuator 114 and a rotating transducer 105 located at the distal end of imaging core 104 of catheter 101. In some embodiments, actuator 114 may rotate transducer 105 at a fixed rate. In some embodiments, actuator 114 may rotate transducer 105 at one or more variable rates.

[0138] Processor 112 can instruct rotary transducer 105 to generate an ultrasonic signal and detect backscattered signals generated by blood and tissue surrounding catheter 101 in response to the ultrasonic signal. In some embodiments, processor 112 can cause rotary transducer 105 to cycle between generating an ultrasonic signal and detecting a backscattered signal. For example, 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 with different frequencies and / or amplitudes. In various embodiments, imaging devices such as IVUS catheters have imaging frequencies (e.g., in the range of 1–90 MHz (e.g., 1–10, 10–15, 10–20, 10–25, 10–30, 10–40, 15–35, 20–30, 30–40, 40–50, 20–25, 20–30, 20–40, 20–45, 20–50, 25–35, 25–40, 25–45, 25–50, 30–45, 30–50, 40–45, 45–50 MHz and any values ​​and ranges thereof). Rotational transduction. Device 105 can detect backscattered signals generated by the blood and / or tissue surrounding the catheter body in response to ultrasound signal 106. Processor 112 can receive the backscattered signals from rotating transducer 105 and generate ultrasound images. In some embodiments, processor 112 can process the backscattered signals by filtering, beamforming, adjusting, and / or transforming them. Processor 112 can provide ultrasound images for display on display device 120. Display device 120 can be any device suitable for providing visual output, including televisions, monitors, mobile devices, tablets, smartwatches, projector screens, etc.

[0139] Processor 112 can execute an imaging software platform. This imaging software platform can provide a user interface for controlling system 100. In some embodiments, processor 112 can generate the user interface on display device 120. The imaging software platform can provide a multi-client interface and an image data platform. In some embodiments, the imaging software can allow a user to hand-draw the boundaries of an ultrasound image. For example, a physician can draw boundaries around a blood vessel displayed on a touch input display, such as a medical-grade tablet, during surgery. In response, system 100 can provide updated images only within the boundaries. The imaging software can provide 3D visualization methods and / or pull-back summaries.

[0140] In some embodiments, the distal end of the conduit 101 houses the imaging transducer 105. Figure 4 The distal end of an elongated member 200 of a catheter 101 according to one embodiment is shown. The elongated member includes an imaging lumen 202 and a rapid exchange (RX) guidewire lumen 204. In some embodiments, the elongated member 200 includes one or more outer sheaths 206. In some embodiments, the RX lumen 204 includes a distal plug 406 at its distal end, such as... Figure 2BAs shown. The imaging lumen 202 of the elongated member 200 may receive a rotary transducer 208 mechanically connected to a drive shaft 210. The lumen 202 may also receive an acoustic coupling medium. This coupling medium may be a liquid or a gel. For example, the coupling medium may be polyethylene glycol (PEG), PEG containing a small amount of water, water, saline, glycerin, natural oil, or combinations thereof. In various embodiments, the coupling medium has a density and sound velocity value similar to the catheter sheath material to prevent or reduce unwanted reflections at the medium / sheath interface and to prevent or reduce refraction of the sound beam. In some embodiments, the sound velocity value of the acoustic coupling medium is configured to improve lateral imaging performance. In some embodiments, the sound velocity value of the acoustic coupling medium is configured for the improved lateral performance. In one embodiment, the geometry of the rotating element catheter may include a focusing lens for ultrasound, which is made of a slightly convex circular layer of material on the transducer surface having a sound velocity slightly lower than that of the material being imaged. In one embodiment, a tightly curved high-sound-velocity shell (catheter body) and an internal material (coupling medium) may be selected, with sound velocities close to and sometimes even higher than those of the material being imaged. In one embodiment, the design of a rotating catheter geometry having a thin, relatively high-speed catheter body and its internal coupling medium can be configured to achieve fairly good focusing. This embodiment can be configured unexpectedly and surprisingly, because the ultrasound focusing lens is made of a slightly convex, circular layer of material on the transducer surface, having a sound velocity slightly lower than that of the imaged material. In one embodiment, a tightly curved, high-speed acoustic shell (catheter body) and its internal material (coupling medium) can be selected, with a sound velocity close to or even higher than that of the imaged material. PEG can be supplied in the range of 5-90% (e.g., 5-10%, 10-25%, 20-50%, 40-80%, and overlapping ranges therewith). 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.

[0141] Figure 3AThe distal end of an elongated member 212 of a catheter 101 according to one embodiment is shown. The catheter includes a plurality of lumens 214, 218. In some embodiments, one lumen 218 may be an overwire (OTW) guidewire lumen. In some embodiments, the catheter may include a guidewire lumen 218. The elongated member 212 may include a distal end 216. According to some embodiments, the elongated member 212 may include a second guidewire lumen 218. An imaging lumen 214 may receive a rotary transducer 208 mechanically coupled to a drive shaft 210. The imaging lumen 214 may also receive an acoustic coupling medium. The guidewire lumen 218 may receive a guidewire, wherein the guidewire lumen 218 extends to the end of the distal end 216. In one embodiment, the guidewire lumen 218 does not contain an acoustic coupling medium. In one embodiment, the lumen space surrounding the transducer 208 contains an acoustic coupling medium encapsulated within the imaging lumen 214.

[0142] Figure 3B It is an isometric view, and Figure 3B A cross-sectional view of the proximal connector hub 300 of one embodiment of the IVUS catheter 101. In one embodiment, the connector hub 300 is made of a rigid material and has one or more flexible seals 304, such as... Figure 3B As shown, this design supports the encapsulated medium while allowing the imaging core 104 and drive shaft 210 to be actuated by rotation and / or linear movement along the conduit axis without media leakage, and prevents air from entering the conduit lumen via one or more seals and / or valves. In one embodiment, a flexible seal 304 surrounds the drive shaft 210 within a rigid connector hub (extending through the flexible seal and distally through the connector hub into the lumen of the conduit body 102) to retain the medium within the lumen as the imaging core 104 rotates. In one embodiment, the flexible seal 304 is a circular (e.g., O-ring) seal that presses firmly against the imaging core 104 of the connector hub 300 with sufficient force to prevent leakage while still allowing a motor or actuator in the imaging console to rotate the imaging core 104 at a rate supporting high imaging frame rates. In various embodiments, the flexible seal 304 is made of nitrile butadiene rubber, nitrile rubber, NBR rubber, acrylonitrile butadiene rubber, ethylene propylene rubber, EPDM rubber, fluorocarbons, fluoroelastomers, fluororubber, synthetic rubber polymers (e.g., Viton), silicone rubber, acrylonitrile-derived rubber, and similar materials. The connector hub 300 can be connected to the proximal connector strain relief device 302 of the IVUS catheter 101. In some embodiments, the drive hub assembly 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 and distinct from the catheter body such that the connector hub 300 is adjacent to or near the proximal end of the catheter body.

[0143] Figure 3A yes Figure 3B A side sectional view of the connector hub 300 shown in the embodiment. 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 in medium communication with the distal interface 303, the proximal interface 308, and / or the medium filling port 312.

[0144] In one embodiment, the connector hub 300 includes a distal interface 303 configured to connect to the proximal end of the conduit body 102. In one embodiment, the drive shaft 210 extends through the distal interface 303. Figure 4 (The part shown).

[0145] In one embodiment, the connector hub 300 includes a proximal interface 308 configured to connect to a connector on the console. In various embodiments, the connector, which is mechanically and / or electrically connected to the console, includes a flexible seal. In one embodiment, a drive shaft 210 extends through the connector and is rigidly attached to the drive hub in the proximal interface 308. When the conduit 101 is connected to the CIM 115 or the console 118, the drive hub interfaces with the actuator 114, such that rotation of the actuator 114 causes rotation of the drive hub, which in turn causes rotation of the drive shaft and the imaging core.

[0146] In one embodiment, the connector hub 300 includes one or more sealing ports 310. A proximal interface 308 may include one or more sealing ports 310. The proximal interface 308 may be proximal adjacent to and connected to or otherwise coupled to the sealing ports 310. In some embodiments, the sealing ports 310 may be orifices in the body of the connector hub 300 and radially positioned above the sealing housing 306. The sealing ports 310 may provide access to the sealing housing 306 and the flexible seal 304. In some embodiments, the sealing ports 310 may allow the connector hub 300 to attach, engage, and / or adhere to the one or more sealing housings 306. For example, adhesive may be applied to the sealing housing(one or more) 306 and the flexible seal 304 through the sealing ports 310. In some embodiments, one, two, three, or more sealing ports 310, flexible seals 304, and sealing housings 306 are used.

[0147] In one embodiment, the connector hub 300 includes a media filling port 312. The media filling port 312 is configured to connect to a source or reservoir of the acoustic coupling medium 109. The media filling port 312 may be configured for inserting the acoustic coupling medium through the connector hub 300 and into the imaging lumen of an elongated member of the IVUS catheter. After the imaging lumen is filled with the medium, the media filling port 312 may be sealed. The media filling port 312 may be shaped to accommodate different connector geometries. The media 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 location of the media filling port 312 may facilitate the removal of all air bubbles during the filling process. In some embodiments, the media filling port 312 may be made with an adhesive and / or similar to those described below. Figure 3B The described method uses a plug for sealing. In one embodiment, the fill port 312 has an inlet located on the nearest side, juxtaposed with the flexible seal 304 to help remove all air bubbles during the filling process. According to some embodiments, the hub may also include a fill port cap and a fill mask. The fill port may receive the fill port cap, which may be a resilient sealing component or a rigid plastic cap. The fill port cap may mate with a fill adapter of the fill nozzle, which can be used to fill the IVUS conduit with the acoustic coupling medium. Optionally, if the fill port cap is a resilient seal, the fill nozzle may include a needle that pierces the seal to fill the conduit. When the IVUS conduit has been filled, the fill nozzle and fill port adapter can be separated from the fill port cap, which is then covered with a fill mask.

[0148] In various embodiments, the connector hub 300 includes one or more flexible seals 304. The flexible seals 304 may surround a drive shaft 210 within the connector hub 300 and seal the coupling medium within the lumen of the conduit body as the core 104 rotates. The flexible seals 304 can be pressed against the core 104 with sufficient force to prevent leakage while still allowing the actuators of the console to rotate the imaging core 104 at a rate supporting high imaging frame rates via the proximal interface 308. In some embodiments, the flexible seals 304 may be assembled internally within the connector hub 300 to ensure precise mating. The connector hub 300 may include one, two, three, or more flexible seals 304. In some embodiments, the flexible seals 304 may have a circular cross-section, or may have a shape such as... Figure 3B The “X” shaped cross-section shown.

[0149] The connector hub 300 may also include one or more sealing housing assemblies 306. In various embodiments, the sealing housing 306 is circular, annular, elliptical, triangular, square, rectangular, and / or polyhedral. For example, as Figure 4As shown in the example embodiment, two sealing housing assemblies 306 may be arranged to receive and contain the flexible seal 304, the connector hub 300, and the proximal interface 308. The inner diameters of the sealing housings 306 may be tightly and precisely matched to ensure appropriate pressure is applied to the flexible seal 304. This appropriate pressure allows the imaging core 104 to rotate without excessive friction and prevents the acoustic coupling medium from leaking through the flexible seal 304. In some embodiments, applying an adhesive to the outer periphery of the flexible seal 304 prevents leakage around the flexible seal 304.

[0150] In a typical clinical setting, the pressure differential across the flexible seal 304 is usually small, so there is virtually no force pushing or pulling air out of the medium. However, outside the clinical operating room, especially during product transport, catheters can be subjected to extreme temperature and / or 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 acoustic coupling medium can cause it to expand or contract, or even change from liquid to solid, thereby increasing or decreasing the encapsulation volume, which in turn leads to increases or decreases in fluid pressure, before returning to the default volume after extreme exposure. Such volume and / or pressure changes can be addressed by the flexibility and / or pressure resistance of the seal 304 so that air bubbles are not drawn into the lumen (in the case of a pressure drop) or fluid leakage is prevented (in the case of a pressure rise). Air entering the lumen can migrate to the distal transducer and degrade image quality. In some embodiments, a dual-sealed housing provides precise assembly and sealing. In one embodiment, a single housing may also be used only on the proximal side.

[0151] Figure 5 This is a side cross-sectional view of a distal portion of the elongated member 400 of catheter 101. According to one embodiment, the distal end may include an outlet port configured for sealing after filling an imaging lumen within the catheter body with an acoustic coupling medium. The elongated member 400 may include a lumen 402 including a distal port 404. (See below for further details.) Figure 4 The lumen 402 may be filled with a coupling medium, and the distal port 404 may be sealed to reduce or eliminate air bubbles in the lumen and reduce or eliminate the need for flushing the catheter lumen. In some embodiments, a distal plug 406 may be attached to a detachable wire 408. In one embodiment, the distal plug 406 is made of a polymer material. In various embodiments, the distal plug 406 may be made of Pebax (polyether block amide), nylon, or other polymer materials to effectively bond and / or thermally weld the plug to the catheter body. In some embodiments, the distal plug 406 may be shaped to conform to the geometry of the distal port 404 and the distal portion of the imaging lumen 402. The detachable wire 408 may be NiTi (nickel-titanium alloy), stainless steel, or other flexible materials.

[0152] In one embodiment, a wire 408 may be fed from a proximal port at the proximal end through a lumen 402 into a distal port 404. In one embodiment, the wire 408 is configured to exit from the distal port 404, leaving a 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 wire 408 may pull the distal plug 406 toward the distal port 404, such that the distal plug 406 seals the distal port 404. In some embodiments, heat may be applied to the distal end of the elongated member 400 to melt and / or adhere the distal plug 406 to the wall of the lumen 402. In some embodiments, an adhesive may be inserted into the distal port 404 to bond the plug 406 to the wall of the lumen 402. After the distal plug is attached to the lumen 402, the wire 408 can be removed from the plug 406.

[0153] In one embodiment, wire 408 may be fed through the imaging lumen 402 from a proximal port at the proximal end of the conduit toward a distal port 404. In one embodiment, wire 408 is configured to exit the distal port 404, while a distal plug 406 remains in the distal portion of the imaging lumen 402. Wire 408 may be removed before the filling process begins. The air passage left in the distal plug 406 forms an effective vent, providing a path for the coupling medium to exit through the distal port 404 during the media filling process. In one embodiment, the space between the distal plug 406 and the imaging lumen 402 further provides a path for the coupling medium to exit. After the filling process is complete, and once all air bubbles have been removed from the imaging lumen 402, the distal port 404 can be closed, thereby sealing the imaging lumen 402. In some embodiments, heat may be applied to the distal end of the elongated member 400 around the distal plug 406 to perform the closing process, causing the distal plug 406 to melt and / or adhere to the wall of the imaging lumen 402. Heat can also close the vents created by the channels from the removed wire. 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, thereby forming an effective seal for the imaging lumen 402. In other embodiments, to close the vents, the wire 408 in the distal plug 406 remains in place until the media filling process stops and the distal plug is secured to the imaging lumen 402. During the filling process, the space around the outside of the distal plug serves as an effective vent, providing an outlet for the moving coupling medium to exit from the distal port 404. Once the filling is completed without air bubbles, heat can be applied to fuse the distal plug to the imaging lumen, and then the wire can be removed. Further heat or adhesive can be applied to close the channels formed by the removal of the wire. In another embodiment, the wire 408 is removed after filling is complete. Heat can then be applied to fuse the distal plug to the imaging lumen, thereby closing the channels formed by the removal of the wire.

[0154] In one embodiment, Figure 5 An optional additional quick-change guidewire lumen 410 is shown. In various embodiments, a distal plug 406 is used, and the quick-change lumen 410 is not present.

[0155] Figure 5 A process 500 for encapsulating a coupling medium within the lumen of an IVUS catheter, according to one embodiment, is illustrated. In some embodiments, process 500 prevents, reduces, and / or eliminates air bubbles that form or remain in the lumen during the filling process, thereby allowing the creation of higher quality ultrasound images. Figure 5The process 500 shown is an example process. In some embodiments, process 500 may include more or fewer steps. In some embodiments, one or more steps in process 500 may be performed in a different order, or simultaneously with one or more other steps in process 500.

[0156] In some embodiments, the degassing process includes subjecting the acoustic fluid to vacuum pressure for a period of time. In one embodiment, the degassing process may begin by providing a degassing device. This 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 conduit and a first valve, such as a diverter valve. The container may be connected to the syringe via a second valve, such as a stopcock valve. The acoustic coupling medium may be placed in the container and maintained for a first time period. The first time period may be a predetermined time period or may continue until the acoustic coupling medium reaches an air saturation threshold. After the first time period, the acoustic coupling medium may be maintained under vacuum pressure for a second time period. The second time period may be a predetermined time period as described below or may continue until the acoustic coupling medium reaches a desaturation threshold. Once the acoustic coupling medium reaches the desaturation threshold, the medium can be delivered to the syringe via the conduit and the second valve. In one embodiment, the magnetic stirring plate is a hot plate, and the degassing process further includes heating the acoustic coupling fluid medium to reduce its viscosity, thereby facilitating the subsequent filling process.

[0157] The IVUS catheter can be filled with a degassed acoustic coupling medium. In some embodiments, the filling process may begin by providing an IVUS catheter filling device, which may include a fluid pump—such as an injection 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-shaped, straight, etc., and may be shaped based on one or more properties of the IVUS catheter.

[0158] In one embodiment, a vacuum pump is attached to the distal outlet port to remove air from the imaging lumen of the catheter, and then the inlet port is opened (e.g., via a valve) to allow media to be drawn into the lumen. In one embodiment, a positive pressure pump may be used instead of or supplement the vacuum pump to push the media into the imaging lumen. In one embodiment, a peristaltic pump is a useful pumping mechanism for propelling the media.

[0159] In one embodiment, process 500 may include step 502, wherein the acoustic coupling medium is degassed. The coupling medium may be degassed by vacuum degassed, ultrasonic treatment, bubbling, or a combination thereof. In one embodiment, vacuum degassed is used because it is simple and effective. Advantageously, in several embodiments, degassed the coupling medium to prevent, reduce, or eliminate the formation of air bubbles in the coupling medium during transport or surgery. Undegassed medium will typically be saturated, dissolving gases from the surrounding environment, and these gases may escape from the solution during the filling process, thus generating air bubbles during and after the filling process. Air bubbles may adhere to surfaces, especially uneven surfaces, making it difficult to completely remove air from the catheter lumen. After degassed, the coupling medium may remain undersaturated for a practical time period, such as the actual filling period. During the actual filling period, the catheter lumen can be filled. Degassed the coupling medium minimizes the risk of air escaping from the solution during the filling process and dissolves any air bubbles present.

[0160] In one embodiment, the process may proceed to step 504, in which the coupling medium is heated. Heating the coupling medium can further remove dissolved gases from it and reduce its viscosity, thereby shortening the time required to fill the catheter lumen. The coupling medium can be heated by conduction, convection, radiation, or a combination thereof. In some embodiments, the coupling medium may be heated in a reservoir used for degassing the coupling medium. In some embodiments, heat may also be applied to the tube and / or the catheter itself used to fill the catheter lumen, thereby heating the interface surrounding the coupling medium.

[0161] In one embodiment, process 500 proceeds to step 506, where the coupling medium is inserted into the lumen of the elongated member. The coupling medium can be inserted by applying positive pressure to a proximal filling port connected to the lumen, pushing the coupling medium into the lumen. For example, a tube can be attached to the proximal port of the elongated member and the lumen, and then a positive pressure pump can be used to push the coupling medium through the tube and into the lumen. The positive pressure pump can be an injection pump, a displacement pump, or other pump capable of applying sufficient controlled pressure to fill the imaging lumen. According to some embodiments, a peristaltic pump can be used to apply a constant positive pressure. In some embodiments, the coupling medium can be inserted by applying negative pressure 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 a proximal valve can be opened, allowing the coupling medium to be drawn into the lumen. In some embodiments, a combination of positive pressure and vacuum pressure can be used to insert the coupling medium into the lumen. For example, a vacuum pump can be attached to the distal port to remove air from the cavity; the proximal port valve can be opened; and the pump can then apply positive pressure to the coupling medium, thereby pushing the medium into the cavity.

[0162] In some embodiments, the coupling medium is inserted into the lumen during the actual filling period. The actual filling period can be defined as a set time during which the coupling medium remains unsaturated with air after the degassing process. The actual filling period depends on the type of medium. The actual filling period can be calculated by measuring the oxygen content in the medium by placing an oxygen sensor in the coupling medium and comparing it to the oxygen content in ambient air. For example, the oxygen content in the coupling medium over time can be measured to quantify how rapidly ambient air is absorbed into the medium. In some embodiments, the actual filling period is set to ensure that only a very small amount of ambient air is absorbed into the medium to support an efficient degassing method. For example, PEG400—a fluid with a viscosity of approximately 100 cP after proper degassing—can have an actual filling period of less than two hours, thereby supporting a manufacturing process that can be used to fill the lumen within a portion of one hour immediately after an optional degassing step is completed.

[0163] In one embodiment, process 500 may proceed to step 508, in which the coupling medium may be agitated by shaking or vibrating one or more surrounding catheter assemblies. For example, the coupling medium may be agitated by moving the imaging core 104 within the coupling medium. For example, the coupling medium may be agitated by vibration of the catheter, rotation of the imaging core 104, and / or longitudinal movement of the imaging core within the lumen. In one embodiment, the catheter is agitated and / or subjected to ultrasonic energy on a vibrating surface.

[0164] Next, the process may optionally proceed to step 510, where the catheter body may be oriented at an angle (e.g., between 0 and 90 degrees between horizontal (e.g., 0 degrees) and vertical (e.g., 90 degrees), for example, oriented at a positive angle above the horizontal). In one embodiment, the catheter may optionally be positioned at an angle above the horizontal until vertical orientation, which may be performed before insertion of the coupling medium. The catheter body may be oriented between horizontal and vertical directions such that the distal end of the elongated member is positioned above the proximal end of the catheter body. In various embodiments, any positive angle catheter orientation above the horizontal can be used to facilitate the removal of any air bubbles from the catheter lumen. In one embodiment, orienting the catheter at a positive angle (e.g., until vertical) may allow air bubbles to migrate upwards out of the distal port to help release air bubbles and visualize an acceptable filling process. In some embodiments, the catheter body may be oriented vertically such that the distal port is located at the highest point of the lumen. In one embodiment, the axis of the catheter is oriented at an angle above the horizontal and less than the vertical, where the vertical is 90 degrees. In some embodiments, any positive angle above the horizontal can facilitate the removal of air, the angle being based on... Figure 4The medium type and process parameters described in the document. Optionally, if this step 510 can effectively remove bubbles without performing it for the selected coupling medium and other process parameters, a zero-angle (no angle) procedure can also be implemented.

[0165] Process 500 may proceed to step 512, where insertion of the coupling medium is stopped. Insertion of the coupling medium may be stopped when the lumen is sufficiently filled with the coupling medium. In some embodiments, insertion of the coupling medium may be stopped when visual inspection confirms that the imaging lumen is full and that there are no air bubbles in the coupling medium. In some embodiments, visual inspection may include a microscope with a magnification of at least 10x. Magnifications of 10x, 30x, 50x, and up to 100x can help identify when there are no more air bubbles in the filled medium. The distal end of the catheter may be visually inspected to ensure that all air bubbles have been completely removed. The size of the air bubbles initially present in the medium may depend on the geometry of the internal components in contact with the medium. In some embodiments, at least air bubbles with a diameter greater than 10-20 micrometers are removed. In some embodiments, if the number of air bubbles is less than 10-20% of the effective surface area of ​​one or more transducers, microbubbles with a diameter less than 10-20 micrometers are unlikely to significantly affect the imaging performance of IVUS. In some embodiments, insertion of the coupling medium may be stopped after a set time period. For example, the set time period can be 5–30 minutes (e.g., 5, 10, 15, 20, 25, and 30 minutes, and any range or value therein). In some embodiments, the volume of the lumen to be filled and the viscosity of the selected medium can both affect the filling time period. In some embodiments, for the same lumen diameter, a longer catheter may require a longer filling time.

[0166] Next, process 500 can proceed to step 514, where the internal cavity is sealed. (As described above...) Figure 6The distal port may be sealed with a plug. The plug may be attached to a flexible wire. The wire may be fed from the proximal port through the internal lumen toward the distal port. The wire may be withdrawn from the distal port, leaving the distal plug in the distal portion of the internal lumen. In some embodiments, the wire and the distal plug may be inserted into the lumen before it is filled with the coupling medium (step 506). The distal plug may be pulled to the distal port by the wire, such that the distal plug seals the distal port. In some embodiments, the distal plug may be bonded to the wall of the internal lumen. Heat may be applied to the distal end of the elongated member to cause the distal plug to adhere to and / or fuse with the wall of the internal lumen. In some embodiments, an adhesive may be inserted into the distal port to bond the plug to the inner and / or outer wall of the internal lumen. After the distal plug is bonded to the internal lumen, the wire may be removed from the plug. In some embodiments, the medium inlet port (e.g., a fluid filling port) of the connector hub may be sealed with a plug or adhesive. In various embodiments, the adhesive is a one-component, single-part, two-part, or multi-part adhesive, such as an epoxy resin, acrylic resin, cyanoacrylate, or ethyl cyanoacrylate adhesive. In various embodiments, the adhesive can be cured, for example using chemical agents, light, or ultraviolet light. In some embodiments, the adhesive retains bonding properties with sufficient adhesive strength after sterilization processes such as steam sterilization, autoclaving, gamma ray sterilization, and / or electron beam (e-beam) sterilization. Examples of adhesives include Loctite, such as 3311, 3922, 4310, 4311, EA-M-21HP, and EA-M-31CL. These examples have good bonding properties and retain sufficient adhesive strength even after gamma ray and / or e-beam sterilization. In some embodiments, the filling port can be self-sealing, i.e., removing the filling nozzle automatically ensures that the port is sealed.

[0167] In some embodiments of process 500, step 502 may occur simultaneously. In some embodiments of process 500, steps 504, 506, 508, and / or 510 may occur simultaneously.

[0168] Advantageously, according to some embodiments, process 500 significantly reduces the risk of undetected air bubbles appearing and degrading image quality. The space inside and around the drive shaft, as well as along the entire length of the catheter, is where air may not be easily and completely removed; therefore, the degassed coupling medium will help remove air from hidden lumens. Air bubbles may also be present in other lumens or interfaces within the main lumen of the catheter. These other lumens may typically be difficult to inspect and air bubbles may not be detected during and after the filling process. Air bubbles may be present after filling, undetected, and may appear during subsequent clinical use.

[0169] According to some embodiments, process 500 allows the internal lumen to be filled with an acoustic coupling medium, thereby minimizing air trapped during a single setup procedure. Process 500 may represent a series of steps in the manufacturing process and allows the catheter to be transported in a "ready-to-use" state so that it can be quickly inserted into the console. Because the coupling medium contains no air bubbles or microbubbles, and no air bubbles will be generated during the procedure, high-quality ultrasound images can be captured without flushing the catheter with saline. Consequently, in some embodiments, procedure time is reduced, higher-quality diagnostic images are captured, and patient outcomes are improved.

[0170] Figure 6 An exemplary process 600 for encapsulating a coupling medium within the inner lumen of an IVUS catheter is shown. Figure 7 The process 600 shown is an example process. In some embodiments, process 600 may include more or fewer steps. In some embodiments, one or more steps in process 600 may be performed in a different order relative to one or more other steps in process 600, or may be performed simultaneously.

[0171] Process 600 may begin at step 602, where the coupling medium is degassed. Step 602 may be similar to step 502 described above. Next, process 600 may proceed to step 604, where the coupling medium may be pushed into the lumen of the catheter via the proximal inlet port and / or drawn into the lumen by a vacuum pump located at the distal outlet port of the catheter. The coupling medium may be heated. Process 600 may proceed to step 606, where filling the internal lumen of the catheter with the coupling medium may be stopped when all air in the internal lumen has been expelled. Step 606 may be similar to step 512. Next, process 600 may proceed to steps 608 and 610, where the distal outlet port and the proximal inlet port may be sealed, respectively. Step 608 may include the process of sealing the distal port as described above in conjunction with step 514. Step 610 may include the process of sealing the proximal port as described above in conjunction with step 514.

[0172] Figure 7 This is an example process for illustrating the process 700 of encapsulating a coupling medium within the inner lumen of an IVUS catheter. Figure 8 The process 700 shown is an example process. In some embodiments, process 700 may include more or fewer steps. In some embodiments, one or more steps in process 700 may be performed in a different order relative to one or more other steps in process 700, or may be performed simultaneously.

[0173] Process 700 may begin at step 702, where the coupling medium is degassed. In one embodiment, the coupling medium is a coupling 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. Next, process 700 may proceed to step 704, where the coupling medium may be pushed into the lumen of the catheter through the proximal inlet and / or drawn into the lumen by a vacuum pump located at the distal outlet port of the catheter. The coupling medium may be heated. Process 700 may proceed to step 706, where the internal imaging core 104 may be moved to expel air. Step 706 may be similar to step 508, where the coupling medium may be agitated using vibration of the catheter, by rotating the internal imaging core 104, and / or by longitudinally moving the imaging core 104 within the internal lumen. Process 700 may proceed to step 708, where filling the internal lumen of the catheter with the coupling medium may be stopped once all air in the internal lumen has been expelled. Step 708 can be similar to steps 512 and 606. Next, process 700 can proceed to steps 710 and 712, wherein, respectively, the distal outlet port can be sealed and the proximal inlet port can be sealed. Step 710 can include the process of sealing the distal port as described above in combination with steps 514 and 608. Step 712 can include the process of sealing the proximal port as described above in combination with steps 514 and 610.

[0174] Figure 9 An embodiment of a catheter 101 for an IVUS system 100 is shown. The catheter 101 may include a catheter body 102, an imaging core 104, and a proximal connector hub 870 with a filler port 860. The imaging core 104 (with a transducer 105) may be positioned within the imaging lumen of the catheter body 102. The catheter body 102 may include a distal end 810, an acoustic window 820, a working length 835 (e.g., 100–200 cm), a hydrophilic coating 830 (e.g., distal 20–80 cm), a central hub 840, a proximal extension 850 (e.g., 100–150 cm), and a proximal strain relief device 855, and is connectable to the proximal connector hub 870 with the filler port 860. In various embodiments, the hydrophilic coating is located on the outer and / or inner surfaces of the catheter (e.g., within the lumen, etc.). In some embodiments, the hydrophilic coating is not located on the outer surface of the catheter. In some embodiments, the hydrophilic coating is not located on the inner surface of the catheter (e.g., in the lumen, etc.).

[0175] Figure 10 An embodiment of an IVUS system 100 is shown, which has various sub-components for an IVUS catheter 101, including a catheter body 102 such as an imaging core 104, a distal catheter sleeve along the working length 835 of the catheter, a proximal extension 850, and including a proximal hub connector 870.

[0176] Figure 11 An embodiment of an imaging core 104 subassembly is shown, which includes 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, transmission system, drive actuator, etc.) supports uniform rotation of the transducer 105 within a cavity filled with acoustic medium. The imaging core 104 can be configured to minimize air bubbles at or around the transducer 105. In one embodiment, the imaging core 104 subassembly may include one or more orifices or holes to improve the filling process.

[0177] Figure 12 The distal end 810 of the RX embodiment of the catheter 101 of an IVUS system 100 according to one embodiment is shown. In various embodiments, the distal end 810 may be flexible, non-invasive, robust (with the ability to pass through occlusions without deformation), and may include a radiopaque marker 812 at the end. In one embodiment, the distal end includes an acoustic window 820 above the transducer imaging plane. The distal end may be configured to seal the coupling medium in the catheter. In one embodiment, the distal end includes a plug 406 for closing a drain or outlet port at the distal end of the imaging lumen 402. The distal end and plug assembly may be formed from a small wire that is then removed to form a drain or outlet port so that air can escape during the fluid filling process. After fluid filling is complete, the drain or outlet port may be closed. In one embodiment, the distal end 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 1-3 cm (e.g., 1.0, 1.5, 2.0, 2.5, 3.0 cm) and supports guidewire insertion into the lumen, which is durable and kink-resistant. In one embodiment, the distal end is a durable end with a tapered distal tip. In one embodiment, the distal end has a radiopaque (RO) mark 812 at or near the distal end. In one embodiment, the distal catheter sheath 835 has a flexible distal region and a stiffer, drivable proximal region. In one embodiment, the distal catheter sheath 835 has an RO mark along its axis. In one embodiment, the distal and axial RO marks may be made of a radiopaque polymer material, such as Pebax and / or tungsten-containing nylon, to improve the visibility and / or opacity of the distal end and / or provide measurement markings during clinical procedures. The RO marks (one or more) may also be platinum, gold, iridium, or alloys thereof, and in various embodiments may be attached to the distal end and / or catheter body 102 by adhesive, die-forging, encapsulation, or other means.

[0178] Figure 13A depiction of an embodiment of the distal end 810 of the IVUS system 100 is shown, wherein 1 mm dividing lines of the measuring scale are located next to the distal portion of the catheter.

[0179] Figure 14 A cross-line OTC embodiment of a catheter 101 for an intravascular ultrasound system 100 is shown. The catheter 101 includes a catheter body 102 and an imaging core 104 (with a transducer 105) configured for connection to a proximal connector hub 870 with a filling port 860. The catheter body may include a distal end 810, an acoustic window 820, a catheter working length (e.g., 90–130 cm) with a distal catheter sleeve 835, a hydrophilic coating 830 (e.g., 20–60 cm distally), a central hub 840, a guidewire exit port 845, a proximal extension 850 (e.g., 120–160 cm), and a proximal strain relief device 855 configured for connection to the proximal connector hub 870 with the filling port 860. In various embodiments, the hydrophilic coating is located on the outer and / or inner surfaces of the catheter (e.g., within the lumen, etc.). In some embodiments, the hydrophilic coating is not located on the outer surface of the catheter. In some embodiments, the hydrophilic coating is not located on the inner surface of the catheter (e.g., inside the lumen).

[0180] Figure 15 Embodiments of various sub-components of IVUS catheter 101 are shown, such as imaging core 104, distal sleeve along the working length 835 of the catheter, proximal extension 850, and proximal hub 870.

[0181] Figure 14 An embodiment is shown. Figure 16 The distal catheter sheath portion 835 of the catheter body 102. In one embodiment, the distal catheter sheath 835 includes a guidewire lumen 847 and an imaging lumen 218, and has a flexible distal region 860, a stiffer, dextrous proximal region 870, and one or more radiopaque (RO) markings 900 at the distal end and along the axis. The imaging lumen 218 may accommodate the imaging core 104 and the acoustic coupling medium.

[0182] Figure 17A distal end 810 according to one embodiment is shown, having an acoustic window 820, a plug 406, a guidewire lumen 847, and an imaging lumen 218. In various embodiments, the distal end may be flexible, non-invasive, and robust (with sufficient stiffness to pass through an occlusion without bending or collapsing), and may include one or more radiopaque markers, such as radiopaque end markers. In one embodiment, the distal end includes an acoustic window located above the transducer imaging plane. The distal end is configured to seal the coupling medium in the conduit. In one embodiment, the distal end includes a plug to close a drain or discharge port, such as an outlet port sealed after a fluid filling step. In one embodiment, the distal end is a durable end with a tapered distal end. In one embodiment, the distal end includes a Pebax with one or more hardness testers and an optional tungsten distal marker band loading to provide visibility of the distal end under fluorescence fluoroscopy.

[0183] Figures 13-16 It shows that according to Figure 18 A cross-section of the catheter shaft (including the sleeve portion) 835 of the catheter body 102 of an embodiment of catheter 101 depicts a guidewire lumen 847 and an imaging lumen 218. According to one embodiment, the cross-section is shown in a digit "8" configuration, with a uniform wall thickness around the transducer portion of the catheter shaft, while the remainder of the shaft has a more rigid elliptical cross-section. In one embodiment, a portion of the catheter includes a substantially uniform polymer thickness within the acoustic window of catheter 101 surrounding the transducer portion, configured for more consistent imaging.

[0184] Figure 13 The diagram shows the middle portion of a catheter body 102 according to one embodiment, including a central hub 840 connecting a distal axial working length 835 and a proximal extension 850 of an imaging catheter 101, as shown. Figure 19As depicted in the diagram. The proximal extension can optionally connect the distal working length 835 to the proximal connector / hub 870. In one embodiment, the proximal extension 850 has a single imaging lumen adjacent to the imaging lumen 218 of the distal working length segment 835. Therefore, it accommodates the proximal half of the imaging core 104 and the acoustic coupling medium. The proximal extension segment is configured to have a bending radius of 2 to 5 inches (e.g., 2, 2.5, 3, 3.5, 4, 4.5, 5 inches and values ​​therein). In one embodiment, the central hub includes a guidewire exit port connected to the guidewire lumen 847 of the distal shaft working length 835. In one embodiment, the central hub is coupled to both lumens of the distal working length 835 of the catheter shaft via a central Y-hub. A sheet in the dual-lumen extrusion can connect the guidewire lumen 847 to the guidewire exit port 845. The materials for the center hub may include Pebax, polycarbonate, polycarbonate / ABS, nylon, transparent materials, and adhesives such as cyanoacrylate or other suitable adhesives.

[0185] Figure 20 A proximal hub 870 of a catheter 101 according to one embodiment is shown. In various embodiments, the proximal hub 870 connects: (i) the catheter shaft to the CIM latching mechanism; (ii) the imaging core 104 to the CIM motor; (iii) an electrical connection between a coaxial cable and the CIM; (iv) the electronic ID (EID) 910 to the catheter interface module; and / or (v) an acoustic coupling medium filling process for the acoustic medium in the supporting sealing device. In one embodiment, the catheter sleeve is coupled to the proximal housing, and the proximal strain relief device 855 provides a transition to the CIM connection 308. In one embodiment, the proximal hub housing includes one or more sealing shells / seals 304, a PCB board 912, a filling port 860, and a latching component. In one embodiment, the imaging core 104 drive shaft is coupled to a drive hub 920, which in turn is coupled to a motor in the catheter interface module. In one embodiment, an internal PCB may enable electrical connections. Materials may include Pebax, polycarbonate, polycarbonate / ABS, nylon, and transparent / transparent materials.

[0186] Figure 21The distal end of catheter 101 according to various embodiments is shown. In various embodiments, the acoustic coupling medium 109 of catheter 101 has acoustic properties similar to blood, is biocompatible, and is configured to fill the imaging lumen without generating (or minimizing) air bubbles within the imaging plane of the acoustic window to reduce or eliminate air bubbles that may interfere with imaging. In various embodiments, the volume of the acoustic coupling medium within the catheter can be as low as 0.5 ml or as high as 4 ml (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 other volumes thereof). In one embodiment, the acoustic coupling medium is colored to facilitate monitoring of the filling process and inspection for air bubbles. In some embodiments, the acoustically attractive medium has a density and sound velocity value similar to that of the catheter sheath material. Increased differences in density or sound velocity values ​​between the medium and the catheter sheath can lead to unwanted strong acoustic reflections and refracted sound pulses, which can degrade image quality. In some embodiments, the acoustic coupling medium has a sound velocity value configured to improve lateral imaging performance. In one embodiment, the geometry of the rotating element conduit may include a focusing lens for ultrasound, the focusing lens being made of a slightly convex circular material layer on the transducer surface, the sound velocity of which is slightly lower than that of the imaged material. In one embodiment, a tightly curved, high-velocity acoustic shell (conduit body) and its internal material (coupling medium) may be selected, with a sound velocity close to, and sometimes even higher than, that of the imaged material. In one embodiment, the design of a rotating conduit geometry having a thin, relatively high-velocity conduit body and its internal coupling medium can be configured to have fairly good focusing performance. This embodiment can be configured to be unexpected and surprising because the ultrasound focusing lens is made of a slightly convex circular material layer on the transducer surface, with a sound velocity slightly lower than that of the imaged material. In one embodiment, a tightly curved, high-velocity acoustic shell (conduit body) and its internal material (coupling medium) may be selected, with a sound velocity close to or even higher than that of the imaged material. In some embodiments, the medium comprises one of polyethylene glycol (PEG), PEG containing a portion of water, water, brine, glycerin, and natural oil. Accordingly, the percentage of the non-PEG portion can be from 80% to 20% (e.g., 80%, 70%, 60%, 50%, 40%, 30%, 20%, and overlapping values ​​and ranges therewith), and in some embodiments, it is in the range of 50% to 30% (e.g., 50%, 45%, 44%, 43%, 42%, 41%, 40%, 39%, 38%, 37%, 35%, 35%, 30%, and overlapping values ​​and ranges therewith), because the latter has a lower tendency to dissolve gases.

[0187] Figure 22 An assembly process for a proximal hub 870 according to one embodiment is illustrated. In various embodiments, the steps may include: mounting and bonding a seal and / or sealing housing, an electronic ID, and an ultrasonic signal PCB for electrical coaxial connection into the proximal hub housing; sliding the ultrasonic signal PCB onto the drive shaft of the imaging core 104; soldering a coaxial cable to the ultrasonic signal PCB; bonding the PCB to the drive shaft with conductive epoxy resin; mounting the drive shaft / PCB into the drive hub; securing with adhesive; assembling the drive shaft / imaging core 104 with the hub housing / seal; applying vacuum grease around the sealing area; placing the imaging core 104 into a conduit sleeve; bonding the sleeve to the proximal hub housing; installing and bonding a strain relief device; and / or attaching a one-way valve to the filling port.

[0188] Figure 23A A filling process for an acoustic coupling medium according to one embodiment is illustrated. In various embodiments, the steps may include: degassing the medium in a vacuum chamber; filling the conduit through a proximal filling port; sealing the discharge port (e.g., an outlet port) at the distal end (e.g., using a heat seal, shrink tubing, adhesive, etc.); sealing the filling port (e.g., an inlet port); and checking for complete filling with few or no bubbles and no leakage. The degassing procedure may be time-sensitive. In one embodiment, a sealed reservoir is used to limit regasification and contamination of the fluid during the handling and filling process. In one embodiment, the fluid filling process may take 5–60 minutes (e.g., 5–20, 20–40, 30–50, 40–60 minutes, and overlapping ranges therewith) at a pressure of, for example, 40–100 psi (e.g., 40–60, 60–80, 70–100 psi, and overlapping ranges therewith).

[0189] Figure 3A An exploded view of a catheter connector hub 2300 of a catheter 101 according to one embodiment is shown. The connector hub 2300 includes a filling cap 2302 and a filling mask 2304. In some embodiments, the connector hub 2300 may be similar to those according to some embodiments. Figure 3B , Figure 19 and Figure 24A The connector hub 300 is shown. The connector hub 2300 can mate with a CIM. According to some embodiments, the connector hub 2300 may include one or more components of the connector hub 300.

[0190] In some embodiments, the catheter connector hub 2300 (i) securely latches in the CIM 115 or console 118 and is easily unlocked during removal; (ii) mates with and establishes an electrical connection to the CIM socket; (iii) mates with the motor drive shaft in the CIM socket and maintains concentric rotation of the rotation shaft; (iv) seals the acoustic coupling medium 109 within 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 the IVUS catheter, which includes an imaging core 2306 attached to the drive shaft 2308. The imaging core 2306 and the drive shaft 2308 may be located within the imaging lumen of the catheter body 2303 of the IVUS catheter 101. The drive shaft 2308 may be a stainless steel thiocyanate tube and is attached to the imaging core 2306. In some embodiments, the IVUS catheter may include a strain relief assembly 2310. Figure 24B , Figure 24C and Figure 23A As most clearly shown, strain relief components can be concentrically arranged around the distal end of connector hub 2300 and the proximal end of catheter body 2303. In some embodiments, strain relief component 2310 can be an assembly of connector hub 2300. Strain relief component 2310 can reduce or prevent kinking and excessive localized strain in the proximal portion of the IVUS catheter. For example, strain relief component 2310 can reduce or prevent kinking when a physician manipulates the IVUS catheter before, during, or after an IVUS procedure. In some embodiments, the strain relief device provides mechanical strength such that catheter body 2303 can bend about a rigid proximal connector hub housing without inhibiting normal rotation of imaging core 2306. In some embodiments, the distal end of strain relief device 2310 is tapered to provide a gradual stiffness transition to the proximal catheter body 2303. In some embodiments, the strain relief device extends distally toward the connector hub 2300 by about 5-10 (7-9 cm) to allow the user to hold the strain relief device portion firmly on the shaft without kinking the IVUS conduit while connecting the connector hub 2300 to the CIM 115 or console 118.

[0191] 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 electronic identification PCB provides catheter identification and bidirectional communication between the catheter and the console of the IVUS system. The seal 2312 seals the acoustic coupling medium within the imaging lumen of the IVUS catheter. The drive bushing 2314 may be concentrically disposed around the drive shaft 2308 and adhered 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 that is adhesively fixed to the hub housing 2301 and configured to prevent coupling medium leakage. In one embodiment, the drive bushing 2314 is configured to capture the seal 2312 within a socket in the sealing shell or hub housing 2301 during assembly to prevent coupling medium leakage. The drive bushing 2314 centers and aligns the drive shaft 2308 within the hub housing 2301 of the connector hub housing 2300. According to some embodiments, the drive bushing can secure or hold the seal 2312 in place at the proximal end of the IVUS conduit. The drive bushing can maintain the drive shaft 2308 in a concentric position with the IVUS conduit. Advantageously, by maintaining the concentric position of the drive shaft 2308, the drive bushing can reduce wobbling and / or non-uniform rotational deformation (NURD) about the central drive shaft axis and can prevent acoustic coupling medium leakage by maintaining uniform friction around the inner diameter of the seal 2312. In one embodiment, an adhesive sealant is applied inside the drive shaft sub-tube to prevent proximal leakage of the coupling medium through the drive shaft sub-tube between the coaxial cable 2305 of the imaging core 2306 and the inner diameter of the sub-tube.

[0192] Connector hub 2300 may include drive hub 2316. Drive hub 2316 may be coupled to the proximal end of drive shaft 2308. Drive hub 2316 may include ultrasound signal PCB 2322. Ultrasound signal PCB 2322 provides electronic communication between transducer 105 of IVUS catheter and imaging console. Cable 2305 of imaging core 2306 is electrically connected to ultrasound transducer 105 at the distal end of imaging core 2306. Cable 2306 extends from the proximal end of imaging core 2306 and is electrically connected to ultrasound signal PCB 2322. Signal PCB 2322 may include one or more electrodes, such as two, three, four or more electrodes. In one embodiment, cable 2305 is a coaxial cable having a metallic inner conductor and a metallic outer shield, with insulating material between the inner conductor and the outer shield and around the outer shield. Electrically connecting the coaxial cable to the ultrasound signal PCB includes: separating the inner conductor and the outer shield, and connecting the inner conductor to one electrode of the PCB and connecting the shield to a separate electrode of the PCB. The one or more electrodes may be coaxial electrical contacts that mate with corresponding spring pins of the CIM. The spring pins may be components of a CIM socket that mates with connector hub 2300. In this way, the ultrasonic transducer of IVUS conduit 101 is electrically connected to console 118 of IVUS system 100.

[0193] In some embodiments, the drive hub 2316 may be held in place by a drive hub pin 2318. In several embodiments, the drive hub pin is a drive hub retaining pin. In several embodiments, the drive hub pin ensures alignment of the drive hub with a mating socket on the conduit interface module and prevents axial movement of the drive shaft 2308 and the drive hub 2316 within the housing. The drive hub pin 2318 may project through an aperture in the housing 2301 of the connector hub 2300 and mate with the drive hub 2316. For example, as... Figure 23B As shown, a drive hub pin 2318 protrudes through a hole in the side of the housing 2301 and mates with a slot in the drive hub 2316. When the conduit is connected to the CIM, the drive hub pin 2318 maintains the position of the drive hub 2316 relative to the connector hub 2300 and / or the mating components of the CIM that mate with the drive hub 2316. According to some embodiments, the drive hub pin 2318 prevents axial movement of the drive shaft 2308. In some embodiments, the connector hub 2300 may include an EID PCB 2320 to provide conduit identification and information, such as conduit type and calibration information. In some embodiments, the EID PCB 2320 may provide electronic communication between the IVUS conduit and the control console.

[0194] 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 integrally formed with the hub housing 2301 of the connector hub. The filling port is configured to allow easy connection and disconnection with the filling nozzle of the manufacturing filling equipment, while reducing or eliminating cavitation or air bubbles introduced into the IVUS system, and is configured to seal against filling pressure. According to some embodiments, the filling port 2324 may be a low-profile design. The filling port 2324 may reduce the risk of air entering the lumen of the IVUS catheter and / or the acoustic coupling medium during the filling procedure. In some embodiments, the filling port 2324 may include a filling port seal 2326 disposed on the bottom surface of the filling port 2324.

[0195] Figure 23B A cross-sectional view of the proximal hub 2300 according to one embodiment is shown. In some embodiments, once the conduit filling process is complete, the filling port 2324 can be sealed by inserting the filling port cap 2302 and the filling mask 2304 into the filling port 2324, as shown. Figure 24A As shown. Filler cap 2302 and filler port 2324 may include threaded assemblies. For example, filler port 2324 may be threaded, and filler cap 2302 may be screwed into filler port 2324. In some embodiments, filler cap 2302 and filler port 2324 may be connected using other mechanical means (e.g., snap-fit ​​and / or adhesive). Once inserted into filler port 2324, filler cap 2302 engages with filler port seal 2326. In some embodiments, filler cap 2302 may include a recess provided on its top side. Filler mask 2304 may be inserted into the recess on the top of filler cap 2302. In some embodiments, filler mask 2304 may be secured to filler cap 2302 using adhesive. In some embodiments, filler mask 2304 may be secured to filler port 2324 using screw engagement, snap-fit ​​and / or adhesive to capture filler cap 2302. In some embodiments, the filling cap 2302 is a seal that opens when the filling nozzle is attached during the filling process, but is sealed when the filling nozzle is removed and / or when the filling mask 2304 is secured to the seal 2302.

[0196] Figure 24BA side cross-sectional view of a connector hub 2300 with a strain relief assembly 2310 according to one embodiment is shown. In some embodiments, the connector hub 2300 may include a hub latch 2402. The hub latch 2402 secures the connector hub 2300 to the catheter interface module. The connector hub 2300 may include a filling port 2324 as described herein. In some embodiments, the strain relief assembly 2310 may engage on the distal portion of the connector hub 2300 and the proximal portion of the catheter body 2301. The strain relief assembly 2310 may engage with the filling port 2324 to conceal the filling port 2324. In some embodiments, the filling port has a low profile and can be easily covered or concealed by a housing or strain relief device, and will not attract the user's attention when it is not needed during catheter use. In some embodiments, the strain relief assembly 2310 may secure and / or secure a filling mask in the filling port 2324. Figure 24C A distal isometric view of a connector hub 2300 with a strain relief assembly 2310 according to one embodiment is shown. Figure 25A A near-side isometric view of a connector hub 2300 with a strain relief assembly 2310 according to one embodiment is shown. In some embodiments, the strain relief assembly 2310 is snap-fitted, press-fitted, and / or adhesively bonded to the connector hub 2300.

[0197] In one embodiment, the filling port and / or filling port cap have features that mate with the end of the filling nozzle to secure the filling nozzle port against filling pressure. In several embodiments, the filling port and filling end have mating threaded features. Figure 25B A side view of a proximal hub 2502 and a filling nozzle 2504 according to one embodiment is shown. The proximal hub 2502 may include a filling port 2506 to receive the acoustic coupling medium via the filling nozzle 2504. The filling port 2506 may be connected to the filling nozzle 2504. In some embodiments, the filling port 2506 may include a seal 2508. The seal 2508 may prevent air from entering the imaging lumen of the IVUS catheter and / or maintain filling pressure.

[0198] The filling nozzle 2504 may include a proximal end 2510 and a distal end 2512. A filling port 2506 may be connected to the distal end 2512. The proximal end 2510 may include a handle or grip assembly to allow a person to hold the filling nozzle 2504. The proximal end 2510 may include at least one port. This port(s) may be connected to a filling device configured to dispense acoustic coupling medium, and the acoustic coupling medium may pass through the filling nozzle 2504 and into the IVUS catheter imaging lumen while venting air from the lumen. The distal end 2512 of the filling nozzle 2504 may mate with the filling port 2506. For example, the distal end 2512 may have a threaded assembly that mates with a threaded portion of the filling port 2506. Other mating features 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 adhered to the distal end 2512. The filling adapter 2514 may mate with the filling port 2506. For example, according to some embodiments, the filling adapter 2514 may be a threaded member and mate with the threaded assembly of the filling port 2506. In some embodiments, the filling adapter 2514 may be integrated with the distal end 2512.

[0199] Figure 26A A side view of a proximal hub 2502 and a filling nozzle 2504, according to one embodiment, is shown, which engage to fill the proximal hub 2502 with a coupling medium. The distal end 2512 of a filling adapter 2514 and / or filling nozzle 2504 can engage with a filling port 2506 of the proximal hub, and the acoustic coupling medium can be pushed or pulled into the imaging lumen of the IVUS catheter. As described above, the acoustic coupling medium can pass through the imaging lumen from the filling port 2506 and exit from the distal port of the IVUS catheter. As described above, the distal port can be sealed as part of the filling process. After filling, the filling nozzle 2504 and filling adapter 2514 can be detached from the filling port 2506. A filling port cap 2302 can be screwed into the filling port 2506 and pressed against a seal 2508 to ensure no air bubbles are present. With pressure applied to the seal, some coupling medium may begin to fill the port. A filling mask 2304 can be inserted and engaged into the filling port cap 2302 to reduce or eliminate air bubbles in the port.

[0200] Figure 26AA fill port 2324 of a connector hub 2300 in the open position according to one embodiment is shown. The fill port 2324 may include a seal 2602. The fill port 2324 may receive a fill port cover 2604. In some embodiments, the fill port cover 2604 acts as a dynamic valve that can close to seal the acoustic coupling medium within the IVUS catheter, thereby reducing air exposure. In one embodiment, a push-in fill method may be used to reduce the IVUS catheter lumen's exposure to ambient air. In some embodiments, the fill port cover 2604 may include a tapered distal end 2606 having one or more orifices. These orifices may allow the acoustic coupling medium to pass through the fill port cover 2604, through the seal 2602, and into the internal imaging lumen of the IVUS catheter. The fill port 2324 initially holds the fill port cover 2604 in the open position. In the open position, the fill port cover 2604 can disengage relative to the seal 2602 and the internal imaging lumen of the IVUS catheter. According to some embodiments, this open position allows the coupling medium to be pulled in or pushed into the imaging lumen.

[0201] The filler valve cap 2604 may include a recess to receive the distal end 2512 of the filler nozzle 2504. In some embodiments, the filler valve cap 2604 may include a threaded portion, such as a threaded recess provided on the top or proximal side of the filler valve cap 2604. The distal end 2512 may include, mechanically coupled to, or adhered to a filler adapter 2514. The filler adapter 2514 may engage and mate with the filler valve cap 2604. For example, as Figure 26B As shown, the filler valve cover 2604 may include a threaded portion located in a central recess. The filler adapter 2514 may also include a threaded assembly that can be screwed into, and thus engage with, the threaded portion of the filler valve cover 2604. In some embodiments, other detachable connection mechanisms may be implemented. For example, spring-loaded snaps or clips, rubber washers, etc.

[0202] Figure 26CA filling port 2324 of a connector hub 2300 engaging with a filling nozzle 2504 is shown according to one embodiment. As described above, a filling port adapter 2514 can engage with a recess in a filling port valve cap 2604. In some embodiments, engagement of the filling port adapter 2514 with the filling port valve cap 2604 initiates the flow of acoustic coupling medium from the filling nozzle 2504 into the internal imaging lumen of the IVUS catheter. Pressure can be applied to the IVUS catheter to cause the acoustic coupling medium to flow into the imaging lumen. In some embodiments, a positive pressure can be applied to the filling nozzle 2504. In some embodiments, a negative pressure, such as a vacuum pressure, can be applied to the distal end of the IVUS catheter. The acoustic coupling medium can flow through the filling nozzle 2504, through the filling port adapter 2514, through the filling port valve cap 2604, through the seal 2602, and into the internal imaging lumen of the IVUS catheter.

[0203] Figure 26D A filling port 2324 of the connector hub 2300 is shown according to one embodiment when the connector hub 2300 is disengaged from the filling nozzle. The filling port 2324 seals the internal imaging lumen of the IVUS conduit. In some embodiments, a filling port valve cap 2604 may seal with the filling port 2324. Sealing the filling port valve cap 2604 and the filling port 2324 may trap acoustic media within the filling port 2324, thereby preventing air from entering the filling port 2324. In some embodiments, sealing the filling port valve cap 2604 and the filling port 2324 may place the filling port assembly in a “closed” position. In the closed position, the tapered distal end 2606 may engage with the seal 2602. Engagement of the tapered distal end 2606 prevents 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 removed. For example, the filling adapter 2514 can be unscrewed from the filling port valve cap 2604. The filling adapter 2514 can be removed without introducing air into the filling port 2324 or the internal imaging lumen of the IVUS catheter.

[0204] Figure 26D A filling port 2324 of a connector hub 2300 in a closed or sealed position according to one embodiment is shown. Figure 27The illustration shows, according to one embodiment, the filling port 2324 and the filling port valve cover 2604 in the closed position after the filling adapter 2514 is disengaged from the filling port valve cover 2604. Removing the filling adapter 2514 can apply a rated pressure to the filling port 2324, thereby drawing the acoustic coupling medium into the filling port 2324 and preventing air from entering the filling port 2324. In some embodiments, a filling mask, such as a filling mask 2304, can be placed in a recess in the filling port valve cover 2604. The filling mask 2304 can be mechanically coupled or adhered to the recess. In some embodiments, the filling mask 2304 can be hermetically coupled to the filling port valve cover 2604.

[0205] Figure 28A An apparatus 2700 for preparing a coupling medium according to one embodiment is shown. In some embodiments, the acoustic coupling medium (i) is degassed to reduce the level of dissolved gases in the medium and absorbs any bubbles accidentally introduced during manufacturing; and / or (ii) is heated before filling the conduit to reduce the viscosity of the coupling medium and accelerate the filling process of the IVUS conduit. 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 tubing and a diverter valve 2710. The container 2702 may be connected to the syringe 2708 via a valve 2712, such as a stopcock valve. The container 2702 may receive and hold the acoustic coupling medium 2714. According to some embodiments, a magnetic stirring rod 2716 may be placed in the container 2702. According to some embodiments, the magnetic stirring hot plate 2706 may be used to heat and / or stir the acoustic coupling medium 2714 by means of the magnetic stirring rod 2716. In one embodiment, the apparatus 2700 may further 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.

[0206] Apparatus 2700 can be used to prepare acoustic coupling medium 2714 for filling IVUS catheters. The process can begin by providing container 2702. In some embodiments, acoustic coupling medium 2714 comprises one of polyethylene glycol (PEG), PEG containing a portion of water, water, saline, glycerin, and natural oils. In one embodiment, acoustic coupling medium 2714 is PEG400. Acoustic coupling medium 2714 can be allowed to stand for a period of time, such as 30 minutes, 60 minutes, 90 minutes, or 120 minutes. The length of this time period is sufficient to allow acoustic coupling medium 2714 to reach air saturation. For example, PEG400 can be allowed 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 therewith). In one embodiment, acoustic coupling medium 2714 is allowed to stand for at least 0.5 to 2 hours. In some embodiments, this time period can continue until acoustic coupling medium 2714 reaches an air saturation threshold. This air saturation threshold can be measured as a deoxygenation percentage (DO%). In various embodiments, the DO% can be reduced by 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 vacuum are applied until degassing reaches 80% or higher DO%. In one embodiment, the saturated medium (e.g., 231.0) and the degassed medium (e.g., 33.9) are measured to obtain a DO% removal rate of approximately 85%. In some embodiments, the air saturation of the acoustic coupling medium 2714 can be detected by a sensor, such as a deoxygenator probe. The settling period can continue until the deoxygenator probe detects that the acoustic coupling medium has reached the air saturation threshold.

[0207] The process can continue, and container 2702 can be partially or completely filled with acoustic coupling medium 2714. Container 2702 can be sealed and configured to be fluidly connected to vacuum pump 2704 via piping and diverter valve 2710. For example, a rubber plug with a fluid connector can be placed on the top opening of container 2702. The rubber plug can be connected to diverter valve 2710, which can in turn be arranged in fluid communication with piping and vacuum pump 2704.

[0208] Vacuum pump 2704 can be activated to remove air from container 2702 and subject the medium to negative pressure. In some embodiments, vacuum pump 2704 may operate for a degassing period. This 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 container 2702, and / or the dimensions of 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 a percentage of the air saturation threshold. For example, the desaturation threshold may be equal to 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 approximately 20% of the air saturation threshold.

[0209] In some embodiments, the magnetic stirring hot plate 2706 can heat the acoustic coupling fluid to a degassing temperature or above. The degassing temperature can be selected based on one or more properties of the acoustic coupling medium 2714. For example, for PEG400, the degassing temperature can be 40 degrees Celsius (°C). In some embodiments, the magnetic stirring hot plate 2706 can stir the acoustic coupling medium 2714 with a magnetic stirring rod 2716.

[0210] In some embodiments, container 2702 may include port 2718. Port 2718 may be located at the bottom of container 2702 and may be used to extract acoustic coupling medium 2714 from the container. In some embodiments, valve 2712 may be attached to port 2718. Syringe 2708 may be attached to valve 2712. To extract acoustic coupling medium 2714, valve 2712 may be opened, such as a stopcock valve, and then syringe 2708 may be used to draw acoustic coupling medium 2714 from container 2702. In some embodiments, valve 2710 may include a thermocouple and / or monitoring cable. The thermocouple and cable may be embedded in valve 2710. The thermocouple may be placed within coupling medium 2714, near the bottom of container 2702. Cable may extend from thermocouple and valve 2710 and connect to a monitoring unit. In some embodiments, monitoring unit may measure temperature. The thermocouple and its cable may extend through a second valve, such as a stopcock valve similar to stopcock valve 2712 according to some embodiments. In addition to the first plug valve 2712, a second plug valve can also be provided. The second plug valve can provide an additional method for measuring the temperature of the acoustic coupling medium.

[0211] Vacuum pump 2704 can be stopped. In embodiments with heating and / or magnetic stirring, magnetic stirring hot plate 2706 can also stop heating and / or stirring of the acoustic coupling medium. Diverter valve 2710 can open at a certain opening rate (which can be a slow rate). This opening rate allows ambient air to enter container 2702 without disturbing medium 2714. Degassed medium 2714 can be removed from container 2702 using syringe 2708. The plunger of syringe 2708 can be pulled to extract acoustic coupling medium 2714 from container 2702. In some embodiments, the deoxygenation percentage of medium 2714 can be detected. If the deoxygenation percentage does not meet the desaturation threshold, vacuum pump 2704 and / or magnetic stirring hot plate 2706 can be restarted, and the process can continue until medium 2714 reaches the desaturation threshold.

[0212] If the medium 2714 meets the desaturation threshold, container 2702 can be repressurized to atmospheric pressure. The acoustic coupling medium 2714 can then be withdrawn from container 2702 using syringe 2708. In some embodiments, syringe 2708 may be one of a plurality of syringes. If the first syringe 2708 is filled, it can be detached from container 2702 and valve 2712. Another syringe can be attached and used to withdraw the medium 2714 from container 2702. In some embodiments, valve 2712 may be one of a plurality of parallel valves. These parallel valves can be used to fill multiple syringes, including syringe 2708, simultaneously.

[0213] In various embodiments, other means are provided for subjecting the coupling medium to heat and negative pressure in a controlled manner.

[0214] Figure 28B An apparatus 2800 is shown according to one embodiment for filling an acoustic coupling medium and / or catheter and heating the acoustic coupling medium and / or catheter during the filling step. The apparatus 2800 may include an infusion pump device 2802 and a catheter heating plate 2804. In some embodiments, the apparatus 2800 may further 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 may 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 acoustic coupling medium and / or one or more properties of the IVUS catheter 2808.

[0215] Figure 29AAn injection pump assembly 2802 for heating a coupling medium is illustrated according to one embodiment. The injection pump assembly 2802 may include an injection pump 2810, a syringe heating assembly 2812, a pressure gauge 2814, at least one conduit 2816, a rotary motor 2818, and / or a three-way valve 2820. The injection pump 2810 may receive one or more syringes, such as syringe 2708, which are filled or partially filled with the coupling medium. The injection pump 2810 may have one or more syringe holders. The syringe holders may be disposed on the top or side of the injection pump 2810. The syringe holders may detachably secure one or more syringes to the injection pump 2810. In some embodiments, the syringe holder may include a U-shaped rubber surface that receives the body of syringe 2708. The injection pump 2810 may include an actuating surface. This actuating surface may be driven by the motor of the injection pump and apply pressure to the piston of syringe 2708. The actuating surface may cause the substance in syringe 2708 to be expelled at a certain delivery rate. The delivery rate can 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 can be based on one or more properties of the acoustic coupling medium used to fill the IVUS catheter. For example, according to some embodiments, the delivery rate of PEG400 can be 0.4 ml / min.

[0216] The syringe heating assembly 2812 may be a syringe sleeve that fits onto the body of the syringe 2708 and heats the syringe 2708. For example, the syringe heating assembly 2812 may be wound around the body of the syringe 2708. The syringe heating assembly (one or more) 2812 may include one or more heating elements. The syringe heating assembly 2812 can heat the syringe to a target temperature. This 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, for PEG400, the target temperature may be 60°C. In some embodiments, the target temperature may be matched with the target temperature of the catheter heating plate 2804. The syringe heating assembly 2812 can heat the syringe to the target temperature for a certain heating period of time. This 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 assembly 2812 can heat the syringe 2708 before and / or during IVUS catheter filling. In some embodiments, according to some examples, the syringe sleeve 2812 can be an assembly of the infusion pump 2810. For example, the infusion pump 2810 may include the syringe heating assembly 2812 within a syringe holder.

[0217] Syringe assembly 2802 may include at least one conduit 2816. Conduit 2816 may be connected proximally to syringe 2708. In some embodiments, conduit 2816 may be connected to syringe 2708 via an air removal filter. In some embodiments, conduit 2816 may be connected to syringe 2708 via a pressure gauge 2814. According to some embodiments, pressure gauge 2814 may provide pressure at the tip of syringe 2708 and / or within conduit 2816 to injection pump 2810. Injection pump 2810 may determine the delivery rate of the contents of syringe 2708 based on the pressure provided by pressure gauge 2814. Pressure gauge 2814 may be monitored to ensure that the pressure within syringe assembly 2802 and / or 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 the IVUS catheter may be 80 psi. If the pressure within the syringe device 2802 or the IVUS catheter exceeds the pressure threshold, the syringe pump 2810 may be stopped, and the pressure within the device 2802 may be allowed to dissipate. In some embodiments, the pressure threshold may be modified if the pressure within the syringe device 2802 exceeds the pressure threshold once or more, twice or more, three or more, four or more, five or more, etc. In another embodiment, if the filling process is designed to satisfactorily fill the catheter without air bubbles, the pressure gauge may be removed.

[0218] At its distal end, conduit 2816 may be connected to connector hub 2300 of conduit 2808 to fill the imaging lumen of the conduit. The proximal connector hub may also be attached to a rotary motor 2818 for rotating the imaging core during filling. For example, conduit 2816 may be attached to connector hub 2300, and the proximal connector hub may also be attached to rotary motor 2818. The distal end of conduit 2816 may be connected to connector hub 2300 via a three-way valve 2820. According to some embodiments, a filling adapter 2514 may be disposed on the distal end of conduit 2816. For example, filling adapter 2514 may be mechanically coupled or adhered to the distal end of conduit 2816. As described above, filling adapter 2514 may mate with the filling port of connector hub 2300. According to some embodiments, conduit 2816 may be part of filling nozzle 2504.

[0219] The syringe device 2802 may include a rotary motor 2818. The rotary motor 2818 rotates the imaging core during the filling procedure. The rotary motor 2818 can operate at a target speed. The target speed rotates the imaging core to help remove air bubbles during the filling process. Agitating the coupling medium 2714 during the filling process helps move and expel air bubbles distally. The target speed may be 1000 rpm ± 100 rpm. Other target speeds may be selected depending on the coupling medium and the viscosity of the selected medium. The target speed may be between 100 rpm and 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 may be reduced if air bubbles are present in the imaging lumen. For example, if the air bubble is stuck and not moving toward the distal port of the imaging lumen. In some embodiments, rotation is a steady state. In other embodiments, the rotation is pulsating.

[0220] 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, a catheter heating plate 2804 can be heated to a target catheter temperature. The syringe 2708 can be placed in a holding assembly of a syringe pump 2810. A syringe heating assembly 2812, such as a syringe sleeve, can surround the syringe 2812 and heat the syringe to a target temperature, such as 60°C. A conduit 2816 can be connected to the syringe 2708 at a first end and to a filling nozzle at a second end, which is connected to a filling port on a connector hub 2300. The syringe pump 2810 can be activated, and the acoustic coupling medium can be discharged from the syringe 2708 into the conduit 2816. The syringe pump 2810 can discharge the acoustic coupling medium from the syringe 2708 at a target flow rate, such as 0.4 mL / min. A rotary motor 2818 can be activated to facilitate the movement of the acoustic coupling medium into the IVUS conduit 2808 and / or assist in removing air from the acoustic coupling medium. According to some embodiments, the rotary motor can operate at a speed of 1000 rpm ± 100 rpm. Pressure gauge 2814 monitors the pressure within tubing 2816 and / or the syringe device to ensure that the pressure does not exceed a pressure threshold, such as 80 psi. This process can continue until the imaging lumen of IVUS catheter 2808 is filled with acoustic coupling medium. IVUS catheter 2808 can be sealed as described herein and subsequently used in IVUS imaging procedures.

[0221] Figure 29B An isometric view of a conduit heating plate 2804 according to one embodiment is shown. Figure 29AA side view of a catheter heating plate 2804 according to one embodiment is shown. As described 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 material. For example, the catheter receiving layer 2906 may be made of aluminum. The catheter receiving layer may include a cutout 2910 to receive the IVUS catheter. The cutout may be of different shapes, for example... Figure 28A The "S" shape shown, or Figure 27 The incision can be either spiral or straight. The incision shape can be based on the type of imaging core of the IVUS catheter placed therein. Heating element 2904 may include one or more individual heating elements. For example, heating element 2904 may be a heating blanket controlled by controller 2912.

[0222] In one embodiment, the acoustic medium preparation device 2700 and the filling device 2800 are the same device. For example, the chamber 2702, connected to a vacuum source for degassing the medium, can also be connected to a pressure source. The pressure or vacuum in the chamber can be controlled by a three-way valve located between the pressure source, the vacuum source, and the chamber. Optionally, the valve is a four-way valve, which can also expose the chamber to ambient pressure. In one embodiment of the manufacturing method, the medium is first exposed to vacuum during a degassing step and then exposed to pressure during a catheter filling step. The medium can be heated during the degassing and / or filling steps. Optionally, the chamber 2702 is connected to a filling syringe, such as... Figure 30 As shown, valve 2712 is a three-way valve that can be configured in one position to fill the syringe from chamber 2702, and then configured in a second position to connect the filled syringe to the filling nozzle.

[0223] In one embodiment, the filling device is connected to multiple filling nozzles via a piping configuration and / or manifold assembly to enable filling more than one conduit at a time.

[0224] Figure 30 A side view of the distal portion of an IVUS catheter 3000 according to one embodiment is shown, wherein an imaging core 104 is contained within a catheter sheath 3206. As described herein, the imaging core 104 may be placed within the imaging lumen of the IVUS catheter 3000. The IVUS catheter 3000 may include a catheter sheath 3206 as described herein. In some embodiments, the imaging core 104 may include a wired transducer 105 located within a transducer housing 3008. The transducer housing 3008 may include openings to allow the transducer 105 to transmit and receive ultrasound signals. For example, as...Figure 30A As shown, the transducer housing 3008 includes an opening located above the transducer 105. The transducer housing 3008 may include one or more housing apertures 3009. In one embodiment, an aperture 3009 is an opening extending through the interior of the transducer housing 3008. In various embodiments, the one or more apertures 3009 may be (i) located near the proximal end of the coil 3004 and / or (ii) along the outer surface of the transducer housing 3008 (e.g., longitudinal, circumferential, or a portion thereof), wherein each aperture 3009 establishes a fluid / air connection with the interior of the coil 3004. The one or more apertures 3009 may allow the coupling medium to fill the interior of the coil 3004 more efficiently during the medium filling process (e.g., compared to a situation without apertures 3009). This helps to reduce or eliminate air bubbles from the conduit 3000. In one embodiment, the one or more orifices 3009 may extend longitudinally, for example along the outer surface of the transducer housing 3008, and allow fluid / air to move distally within the coil 3004 and exit the housing during the medium filling process. Figure 31 An example cross-section of the proximal portion of the transducer housing 3008 is shown, revealing an aperture 3009 connecting the interior of the coil 3004 to the top opening surface of the transducer 105. The wired transducer 105 and the transducer housing 3008 can be coupled to a drive shaft containing the coil 3004 via a coupler 3010. In some embodiments, the coupler 3010 supports a robust mechanical connection between the transducer housing 3008 and the coil 3004. The coupler can be laser-welded or bonded to the juxtaposed components using adhesive. The coupler 3010 may include one or more apertures 3009.

[0225] Figure 32 A side view of the proximal hub 3102 of an IVUS conduit 3100 according to one embodiment is shown. As described herein, the IVUS conduit 3100 may include a proximal drive shaft, such as a hypotube 3104. The drive shaft 3104 may include one or more apertures 3106. The one or more apertures 3106 may allow an acoustic coupling medium to enter the drive shaft and move more easily through the coil 3004. The one or more apertures 3106 may allow air to exit the imaging core from within the coil 3004.

[0226] Figure 32 A cross-section of an IVUS catheter 3200 is shown. As described herein, the IVUS catheter 3200 may include an imaging core 104 and a catheter sleeve 3206. According to some embodiments, the imaging core 104 may include a coil 3204 and a coaxial cable 3202, both disposed within the internal imaging lumen 108 of the IVUS catheter 3200 formed by the catheter sleeve 3206. Figure 30As shown, a first gap 3208 may exist between the coaxial cable 3202 and the coil 3204, and a second gap 3210 may exist between the coil 3204 and the conduit sleeve 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.

[0227] In some embodiments, coil 3204 may have an inner diameter of about 0.005”-0.030” (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 about 0.015”-0.045” (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, sleeve 3206 may have an inner diameter of 0.020”–0.050” (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, coaxial cable 3202 may have an outer diameter of 0.002”–0.025” (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 in the range of 1.5 to 3.0 times the area between coaxial cable 3202 and coil 3204 (e.g., 1.5, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0 times). A smaller area can result in a larger area with greater media filling resistance. Depending on the size of the selected IVUS conduit 3200, other inner and outer diameters may be used, and the difference between the two areas may vary. In some embodiments, the media flow relative to the area outside coil 3204... Figure 30A , Figure 31 and Figure 33 The orifice described herein reduces the medium flow resistance for removing air from inside coil 3204, thereby improving the speed and efficiency of the filling process, and / or effectively removing air during the filling process.

[0228] Figure 34The diagram illustrates the flow of an acoustic coupling medium through the imaging lumen of an IVUS catheter 3300 during the filling process, according to some embodiments. The acoustic coupling medium may flow through orifices in the drive shaft 3104, coupler 3010, and / or transducer housing 3008. Advantageously, one or more orifices 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. Typically, IVUS catheters may have a small diameter for insertion into human blood vessels. This may result in the rotating imaging core optionally having a small diameter for insertion into an external catheter polymer sheath. These components may occupy a large portion of the available space within the catheter lumen, leaving very small air spaces that may need to be effectively displaced with the coupling medium during each effective filling process. Poorly designed geometry of the components can impede air removal; therefore, the object of this application is to support the flow of the coupling medium through the lumen and the ejection and / or pull-out of air in some embodiments. The acoustic coupling medium may have a high viscosity, which presents an additional challenge during the filling process. For example, the viscosity of the acoustic coupling medium can significantly slow down the filling process. Therefore, the purpose of this application is to provide component designs that support a more efficient and cost-effective filling method in some embodiments.

[0229] Figure 27 This is a process 3400 according to one embodiment for degassing an acoustic coupling medium and filling an IVUS catheter. Process 3400 may begin at step 3402, wherein a degassing device, such as device 2700, is provided. The degassing device may include one or more components of device 2700. Process 3400 may proceed to step 3404, wherein the acoustic coupling medium is held in the ambient environment for a first time period. The acoustic coupling medium may be placed in a container of the degassing device, such as container 2702. The acoustic coupling medium may be held in the ambient environment until it reaches air saturation, as described above. Figure 27 The first time period can be 30 minutes, 60 minutes, 90 minutes, 120 minutes, etc. This first time period can continue until the acoustic coupling medium reaches the air saturation threshold.

[0230] Process 3400 can proceed to step 3406, wherein the acoustic coupling medium can be maintained under vacuum pressure for a second time period. As described above, the acoustic coupling medium can be placed in container 2702, and vacuum pump 2704 can be turned on to remove gas from container 2702 during at least a portion of the second time period. The second time period can be 30 minutes, 45 minutes, 60 minutes, 75 minutes, 90 minutes, 105 minutes, 120 minutes, etc. The second time period can be based on the acoustic coupling medium and its properties, the volume of the acoustic coupling medium placed in container 2702, and / or the dimensions of container 2702. During the second time period, a magnetic stirring hot plate can heat and / or stir the acoustic coupling medium.

[0231] Process 3400 may proceed to decision step 3408, where it is determined whether the acoustic coupling medium meets a desaturation threshold. In some embodiments, the desaturation threshold may be a certain percentage of the air saturation threshold. For example, the desaturation threshold may be equal to 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 approximately 20% of the air saturation threshold. If the desaturation threshold is not met, the process may return to step 3406, and the acoustic coupling medium may continue to be held under vacuum pressure until the desaturation threshold is met.

[0232] If the desaturation threshold is met, the process proceeds to step 3410, where the acoustic coupling medium is transferred to a syringe, such as syringe 2708. As described above, container 2702 may include valve 2712. Syringe 2708 may be attached to valve 2712 and may be used to extract the acoustic coupling medium from container 2702, as described above. Figures 23A-23B In some embodiments, the acoustic coupling medium can be transferred to multiple syringes.

[0233] Process 3400 may proceed to step 3412, where the IVUS conduit 2808 is heated to a target temperature. In some embodiments, the IVUS conduit 2808 may be heated to the target temperature by a tube heating plate, such as conduit 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 conduit target temperature may be based on one or more properties of the acoustic coupling medium and / or one or more properties of the IVUS conduit 2808.

[0234] According to some embodiments, process 3400 may proceed to step 3414, where IVUS catheter 2808 may be filled. As described above, IVUS catheter 2808 may include a proximal connector hub, such as proximal connector hub 300 or 2300. The proximal connector hub may include a filling port, such as filling port 2324. IVUS catheter 2808 may be filled by inserting a syringe filled with acoustic coupling medium into an infusion pump device, such as infusion pump device 2802. Infusion pump device 2802 may be activated as described above and used to fill IVUS catheter 2808 through filling port 2324, as in combination Figure 24A , Figures 26A-26D , Figure 28A , Figure 28B and Figures 25A-25B The syringe device 2802 may include an injection pump 2810 that can expel the acoustic coupling medium from the syringe 2708 at a target flow rate, such as 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 may be used to agitate the IVUS catheter 2808 to remove air from the acoustic coupling medium.

[0235] Process 3400 may end at step 3416, where 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, by means of the combination described above. Example 1. Method of filling an IVUS catheter with an acoustic coupling medium The mechanism described in 26A-26D.

[0236] According to some embodiments, method 3400 may include more or fewer steps. The steps of method 3400 may be performed in a different order or simultaneously relative to one or more other steps of the process.

[0237] Endoscopy and other non-vascular imaging may incorporate several of the features described herein. For example, transvaginal ultrasound devices and other gynecological ultrasound devices may include several of the features described herein. Although the above figures may refer to IVUS catheters, in those embodiments performing endoscopic ultrasound and other endocavitary imaging (or imaging of other body cavities or organs) (and such imaging is not within blood vessels), the features described herein for “IVUS” or “catheter” apply to endocavitary (including EUS, cavities, organs, etc.) catheters, probes, tubes, endoscopes, etc.

[0238] This document provides some embodiments of medical imaging systems, such as IVUS systems. Advantageously, according to some embodiments, such systems include one or more improvements over conventional IVUS systems, such as enhanced imaging, image-guided therapy, enhanced usability, easier setup, streamlined clinical workflows, reduced operation time, improved clinical efficacy, improved diagnostic image accuracy, improved accuracy of therapeutic intervention delivery, improved guided interventional therapy, more efficient peripheral interventions, faster informed treatment decisions, and faster measurement and reporting. In some embodiments, IVUS is a diagnostic image-guided therapy tool for treating both peripheral arterial and venous diseases, thereby enabling 2D and / or 3D endovascular visualization.

[0239] For example, the use of non-flushing catheters for image interpretation and measurement of luminal geometry (e.g., diameter, stenosis, peripheral interventional procedures, coronary interventional procedures, atherosclerotic plaque resection, lithotripsy, intravascular lithotripsy (IVL), balloon placement, stent placement, venous procedures, below-knee (BTK) procedures, arteriovenous fistulas, and other procedures) can be performed using the embodiments described herein. Procedures can be performed by interventional cardiologists, radiologists, and / or vascular surgeons in hospitals, physician offices, office laboratories (OBLs), and / or outpatient surgical centers (ASCs). In some embodiments, the systems described herein can be used efficiently in hospitals and OBLs / ASCs without requiring specialized clinical support. Interventions can include treatments or other interventions such as peripheral interventional procedures, coronary interventional procedures, atherosclerotic plaque resection, IVL, balloon placement, stent placement, venous procedures, BTK procedures, arteriovenous fistulas, and other procedures. Imaging can include, for example, IVUS of non-coronary peripheral vessels, IVUS of coronary vessels, ultrasound, intraluminal imaging, body cavity and organ imaging, and other imaging methods (and combinations thereof) as described herein.

[0240] Many of these embodiments should be particularly beneficial in ensuring that patients avoid unnecessary additional diagnostic or interventional procedures, which in turn provides better patient care and reduces the short-term burden on the healthcare system. Similarly, many of these embodiments help patients receive the necessary additional diagnostic or interventional procedures they require, which in turn provides better patient outcomes and reduces the long-term burden on the healthcare system (by treating patients earlier in the disease progression timeline). In some embodiments, IVUS systems with flushing catheters provide a modern IVUS platform and catheter combination that offers improved availability at a competitive cost, excellent image interpretation, and a simplified bedside workflow, enabling broader application.

[0241] In some embodiments, one or more of the following features are provided:

[0242] Plug-and-play catheters: According to some embodiments, flush-free catheters are optimized for vascular imaging and configured to provide superior maneuverability, tracking, and traversal capabilities in arterial and venous vascular systems. In some embodiments, the catheter has superior maneuverability to avoid kinking and sufficient column strength to allow it to traverse tortuous bends and occlusions in the vascular system without buckling, excessive bending, or collapse anywhere along the catheter (e.g., being able to pass through occlusions or stenosis). In some embodiments, the catheter has superior tracking capabilities to allow it to follow a guidewire through tortuous bends in the vascular system, with sufficient flexibility and strength to move along the guidewire and advance to a target location within the vascular system. In some embodiments, the catheter has superior traversal capabilities to traverse occlusions, restrictions, and constrictions within the vascular system, such as sites of tissue obstruction (e.g., stenosis) and / or implant obstruction (e.g., stents, balloons, etc.). Systems described herein, such as IVUS catheters, may include a plug-and-play rotating design, e.g., the catheter can be removed from its sterile packaging and ready for use without flushing. In one embodiment, the catheter has a single rotating ultrasound element. In some embodiments, the catheter includes an encapsulated coupling medium (e.g., coupling medium, medium, liquid, fluid, gel, etc.) that supports a rotating imaging core within the catheter sheath. In one embodiment, the IVUS catheter is a plug-and-play catheter with a non-rinsing peripheral disposable imaging design, 280 cm in total length and 150 cm in working length, compatible with 0.014-inch guidewires and 5F sheaths, allowing the IVUS catheter proximal connector to attach to a CIM outside the sterile area. In another embodiment, the IVUS catheter is a plug-and-play catheter, a non-rinsing peripheral disposable imaging catheter, 250 cm in total length and 110 cm in working length, compatible with 0.035-inch guidewires and 8F sheaths, allowing the IVUS catheter proximal connector to attach to a CIM outside the sterile area. Connections outside the sterile area optionally avoid the need for a suspending motor unit with cables within the sterile area. In some embodiments, high-definition (e.g., HD, Ultra-high-definition (UHD), UHD, HD+, etc.) imaging uses acoustic pulse echoes with matched excitation spectra to achieve 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 within a polymer sleeve using an internal drive shaft connected via a proximal hub / connector. The hub connector is optionally attached to the CIM after removal from its sterile catheter package. A transducer located at the distal end of the imaging core can rotate between 1500 and 4000 rpm and receive echoes for processing into a circular image on a tablet computer display. The catheter can be 8 to 10 feet long. In various embodiments, the catheter can be removed from its sterile package and ready for use without flushing the device. These lengths allow the proximal catheter connector to be connected to the CIM outside the sterile area.In one embodiment, connecting outside the sterile area avoids the need to suspend the cabled motor unit inside the sterile area. The catheter may include non-volatile memory containing a unique catheter identifier, usage data, and calibrations for achieving optimal imaging performance. According to some embodiments, calibration may include data related to measurements of impedance versus frequency, acoustic sensitivity versus frequency, and / or device-specific beam profile data.

[0243] Catheter Interface Module: According to some embodiments, the CIM is a hardware interface between the system cable from the workstation and the disposable catheter. In some embodiments, the CIM provides rotation drive and ultrasound signal processing capabilities for the system (e.g., an IVUS system). Custom electronics control the motor that rotates the imaging core inside the catheter. This electronics can also transmit and receive ultrasound signals between a rotary transducer located distal to the catheter tip and a custom printed circuit board within the workstation. In various embodiments, the CIM provides an interface for reading and writing to non-volatile memory, such as within the catheter. The memory can be used to calibrate the ultrasound transducer for each unique catheter. In one embodiment, the catheter memory can be used to select a suitable system configuration for potentially optimal 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.), which 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 area. In some embodiments, the CIM is embedded or integrated into an imaging control device, workstation, housing, worktable, bed, base, platform, and / or trolley. In some embodiments, the CIM is located outside the sterile area. In some embodiments, one or more ports are provided to allow seamless connectivity between the IVUS system and other imaging modalities.

[0244] Image co-registration: In some embodiments, the IVUS system provides co-registration data to provide 1:1 colocation identification, thereby achieving treatment precision. Advantageously, some embodiments described herein can work in conjunction with or independently of co-registration with other imaging modalities, such as fluoroscopy, where software algorithms track radiopaque (RO) catheter markers (one or more) or RO transducers throughout continuous fluoroscopy recording. For example, co-registration with angiography can be used to determine the 3D shape of vessels, lumens, and lesions, including lesion length, efficient stent selection, and efficient stent landing site positioning, in an attempt to shorten procedure time, reduce contrast agent use, and make IVUS more comfortable for practitioners. Several embodiments described herein achieve one or more of these benefits, with or without co-registration.

[0245] Synergistic effects of vascular intervention: In some embodiments, the IVUS system is configured to optimize vascular procedures. Many of the systems and methods described herein can be used for peripheral, coronary, and other endovascular applications. Other embodiments can be used for non-endovascular applications, such as endoscopy.

[0246] For example, an endoscope may be used in conjunction with some of the features described herein. Transvaginal ultrasound devices and other gynecological ultrasound devices may also include some of the features described herein. For embodiments in which EUS (endoscopic ultrasound) and other intracavitary imaging or imaging of other body cavities or organs (and such imaging is not performed within blood vessels) are performed, the features described herein for “IVUS” or “catheter” should be understood to apply to intracavitary (or other cavity / organ) catheters, probes, tubes, endoscopes and other such devices.

[0247] In some embodiments, the systems and methods are configured and optimized for peripheral vascular surgery (rather than for coronary vascular surgery). In one embodiment, systems and methods configured, designed, or adapted for the peripheral vascular system, individually or primarily, include one or more of the following features: flexibility, maneuverability, length, diameter, material, and / or bending strength, to improve intraluminal maneuverability, trackability, and traversability (e.g., the ability to traverse obstacles or stenosis). 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 prior to treatment, for example, to identify and plan treatment procedures. In some embodiments, the system is configured to image and / or measure tissue post-treatment, for example, to confirm the outcome and efficacy of the treatment. In some embodiments, the system is configured to image and / or measure tissue during treatment.

[0248] Artificial Intelligence: In some embodiments, the systems described herein, including, for example, advanced intravascular ultrasound platforms, utilize AI for image interpretation, enhancing overall system functionality and streamlining workflows to maximize clinical value. Advantageously, in some embodiments, physicians are not required to spatially and temporally integrate (e.g., cognitively integrate) image data to comprehensively interpret clinical conditions. Instead, systems according to some embodiments described herein can leverage the power of AI and generational advancements to go beyond single image interpretation. In some embodiments, for example, an AI-powered engine may include a workstation that enhances image interpretation through a streamlined workflow, thereby improving overall usability. Machine learning is used in some embodiments. In one embodiment, AI-ready processing capabilities are designed to support real-time and on-demand image interpretation. AI-driven workstations can provide high-end processing as well as an AI engine for advanced signal and image processing. In various embodiments, native image data capture provides superior image interpretation (e.g., boundary detection, identification and measurement of vessel size, vascular disease, dissection, plaque morphology, etc.). In some embodiments, the systems described herein provide simplified measurements through automated boundary detection (e.g., AI algorithms automatically identify boundaries of lumens, vessels, tissues, lesions, plaques, etc.). In some embodiments, the system provides simplified measurements through semi-automatic boundary detection (e.g., the user can manually adjust or modify an automated AI algorithm that identifies the boundaries of lumens, vessels, tissues, lesions, plaques, etc., and reconfigure boundary selection based on the user's modifications). In one embodiment, AI plaque identification utilizes AI algorithms to automatically classify and identify plaque types within the imaging area to provide user guidance on treatment options (e.g., color coding, icons, or text overlays can be used to indicate what type of condition, such as plaque, might be present in the selected image). In some embodiments, the data-driven platform is designed to collect data, simplify image interpretation, and leverage AI processing capabilities to support real-time and on-demand image interpretation, and reduce the user's cognitive load, thereby helping (i) identify lumen size, (ii) visualize anatomy, (iii) characterize disease morphology, (iv) locate and quantify stenosis, and / or (v) identify the actual lumen. In some embodiments, image interpretation is used to identify thrombi, thrombosis, blood clots, embolisms, plaques, calcifications, tissue health, stent or balloon alignment, and / or the "health" or condition of stents or balloons. Image interpretation may involve imaging to assess the quality and / or placement of an existing stent. Image interpretation may involve identifying its position relative to the luminal wall and determining the level and / or quality of tissue growing within and around the stent or balloon.In one embodiment, for example, for a bioresorbable stent, image interpretation may involve: (i) assessing the amount of stent dissolution; and (ii) determining whether the stent dissolution conforms to an expected attenuation pattern (e.g., determining whether the attenuation level on one side of the stent is similar to that on the other side, and if they differ, it may indicate a problem with stent placement; or, if the stent dissolves more rapidly than expected, it may indicate that the stent is failing to provide the expected structural support to the tissue). In one embodiment, high-fidelity ultrasound data is used to drive improved image generation and interpretation, and artificial intelligence and / or machine learning may be utilized. In various embodiments, catheters, devices, systems, and methods may be configured to perform edge-based machine learning computations related to images or image analysis, using artificial intelligence algorithms to identify tissue boundaries, plaques, calcium, thrombi, dissections, and / or stent apposition. In some embodiments, data, algorithms, AI, and / or ML are used to acquire data from one or more sensors and provide feedback on operational aspects (e.g., imaging parameters) via feedback loops (e.g., closed-loop feedback / automation) or through user-guided adjustments. In some embodiments, data, algorithms, AI, and / or ML are used to acquire data from one or more images and provide feedback on operational aspects (e.g., imaging parameters and / or treatment) via feedback loops (e.g., closed-loop feedback / automation) or via user-guided adjustments.

[0249] In some embodiments, the imaging described herein is used to diagnose whether a patient is suitable for a specific intervention or further diagnosis. In various embodiments, 2D and / or 3D endovascular visualization can be achieved. In one embodiment, 2D imaging includes images in a single plane. In some embodiments, 3D imaging includes a volumetric representation of tissue or lumen. In some embodiments, 3D imaging is reconstructed by an algorithm that inserts a series of 2D images in a third dimension, acquires a series of individual 2D images and estimates linear progression along the third dimension, and uses artificial intelligence (AI) to generate a 3D volumetric representation of the inserted 2D images. In some embodiments, 3D model generation may involve acquiring 2D cross-sectional images of a vascular object, allowing an encoder or other sensor to record the location (e.g., insertion length) along a vein or artery. Drawing each 2D cross-section in 3D at the insertion length where the recorded cross-section is located can allow the construction of a 3D model of the vascular object. In one embodiment, adding an electromagnetic sensor to the catheter tip can allow the location of the catheter tip to be recorded while acquiring 2D images, thereby allowing the creation of a 3D model of the vascular structure. 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, 3D visualization is generated by interpolating the geometry of linear and / or nonlinear vascular structures and acoustic reflections from the tissue. In one embodiment, pixel-based interpolation is used to visualize the three-dimensional vascular anatomy. In some embodiments, a series of cross-sectional two-dimensional IVUS images and / or signals are generated from pixel-based vascular sectional images, showing acoustic reflection information along the luminal length. In one embodiment, 3D visualization is generated through smooth 3D surface rendering using an algorithm for creating anatomical contour boundaries. In some embodiments, AI is employed to create the 3D visualization data and images.

[0250] In some embodiments, coronary artery systems and methods are provided. In some embodiments, devices (e.g., coronary IVUS catheters) employ smaller diameters, higher stiffness, and improved coronary artery-specific maneuverability, tracking, and / or traversal characteristics. Catheters used for coronary applications can employ different ultrasound frequencies to account for variations in tissue lumen size: for example, peripheral vascular systems may have larger vessel diameters, thus allowing for ultrasound imaging at lower frequencies to capture images at greater distances from the IVUS catheter transducer. In some embodiments, coronary arteries have smaller diameters, thus allowing for imaging ultrasound frequencies of approximately 60 MHz, while peripheral imaging may use lower frequencies, such as approximately 40 MHz or lower. In some embodiments, the coronary IVUS catheter requires lower column strength to achieve maneuverability or traversal due to the presence of a guiding catheter.

[0251] In some embodiments, catheters optimized for vascular imaging are configured to have excellent maneuverability, trackability, and traversability through arterial and venous peripheral vascular systems. In some embodiments, one or more of the following features are provided:

[0252] Maneuverability: In some embodiments, the catheter exhibits excellent maneuverability to avoid kinking and has sufficient column strength to allow the catheter to advance through tortuous bends and occlusions in the vascular system without buckling, excessive bending, or collapsing anywhere along the catheter (e.g., proximal or (e.g., the ability to pass through occlusions or constrictions)). Material properties (e.g., balance of stiffness and flexibility, rigidity of individual segments) and dimensional characteristics (e.g., larger dimensions, such as diameter and thickness) in some embodiments increase column strength, taking into account greater maneuverability and resistance to kinking.

[0253] Trackability: In some embodiments, the catheter has excellent tracking performance, enabling it to follow the guidewire through the twists and turns of the vascular system, possessing sufficient flexibility and strength to move along and advance along the guidewire to the target location within the vascular system. A hydrophilic coating, according to some embodiments, helps reduce friction with surrounding luminal tissue.

[0254] Transit Capability: In some embodiments, the catheter has excellent transit capability to traverse occlusions, restrictions, and constrictions within the vascular system, such as at sites of tissue obstruction (e.g., stenosis, etc.) and / or implant obstruction (e.g., stents, balloons, etc.). According to some embodiments, transit capability is enhanced by one or more of the following: (i) the design of the distal tip (e.g., sufficiently sharp to traverse occlusions, etc., and sufficiently blunt to avoid being hooked by occlusions), (ii) material properties (e.g., a balance of rigidity and flexibility, stiffness of different segments, etc.), and / or (iii) dimensional characteristics (e.g., larger dimensions, such as diameter and thickness, increasing column strength). In one embodiment, low stiffness is provided near the distal tip to flexibly traverse tortuous anatomy and obstructions. In one embodiment, a varying or stepped gradient region is provided proximally towards higher stiffness, sufficient to propel the catheter while avoiding kinking. A single stiffness and / or flexibility may remain constant along one or all portions of the device.

[0255] The techniques described herein are used in some embodiments to focus intraluminal images using a rotating single-element ultrasonic transducer by modifying the image (e.g., angular diffraction, phase, amplitude, time shift, synthetic backscatter reflection image), including the techniques described in U.S. Patent No. 63 / 497,962 entitled "Spinning Single Element Ultrasound Transducer and Focusing Methods" (and a PCT application claiming priority, filed April 11, 2024); manual assisted pullback, voice control, and position sensors (e.g., encoders) for spatial alignment measurements, including System and Methods of Manually Assisted Pullback for Spatial Alignment Lengthwise Measurements in Intravascular The technologies described in U.S. Patent No. 63 / 546,058 entitled “Systems and Methods for Intravascular Ultrasound”; and ultrasound imaging systems and components, voice control and artificial intelligence algorithms, including the technologies described in U.S. Patent No. 63 / 546,058 entitled “Systems and Methods for Intravascular Ultrasound”, are all incorporated herein by reference in their entirety.

[0256] Example

[0257] The following examples are non-limiting examples.

[0258] Example 2. Method of filling an IVUS catheter with an acoustic coupling medium

[0259] In the experiment, a method of filling an IVUS catheter with an acoustic coupling medium was performed, using PEG400 as the acoustic coupling medium to fill the internal imaging lumen / cavity of a prototype catheter. A prototype "014 catheter" with a 0.014-inch outer diameter guidewire was configured for peripheral vascular imaging. This prototype features an internal rotating core comprising a coaxial double-layer torque coil drive cable and a module at the end of the drive cable with an analog acoustic transducer sized for high-quality imaging. The catheter sleeve is consistent with commercially available IVUS catheters. For the 014 catheter, the overall length is longer than the existing commercially available 280 cm IVUS catheter. The significantly longer lumen encapsulated with the coupling medium is intentionally designed to challenge encapsulation methods, as longer lumens are more difficult to fill. The prototype catheter was successfully filled with PEG400, and all air bubbles were expelled from the internal imaging lumen. Alternatives to PEG400, such as other low molecular weight grades of polyethylene glycol and other materials, may be used in other embodiments.

[0260] ​

[0261] In another experiment, PEG400 was used as the acoustic coupling medium to fill the internal imaging lumen / cavity of a prototype catheter. A prototype "035 catheter" with a 0.035-inch outer diameter guidewire was configured for peripheral vascular imaging. This prototype features an internal rotating core comprising a coaxial double-layer torque coil drive cable and a module attached to the end of the drive cable of an analog acoustic transducer, sized for high-quality imaging. The catheter sleeve is consistent with commercially available IVUS catheters. For the 035 catheter, the overall length is longer than the existing commercially available 250 cm IVUS catheters. The lumen length encapsulated with the coupling medium is significantly longer than commercially available catheters, intentionally designed to challenge encapsulation methods, as longer lumens are more difficult to fill. The prototype catheter was successfully filled with PEG400, and all air bubbles were expelled from the internal imaging lumen. Alternatives to PEG400, such as other low molecular weight grades of polyethylene glycol and other materials, may also be used in other embodiments.

[0262] Changes and modifications can be made to the embodiments described herein without departing from the principles of this disclosure. Each disclosed aspect and example can be considered alone or in combination with other aspects, examples, and variations of this disclosure. Furthermore, unless otherwise stated, any step of the method of this disclosure is not limited to any particular order of execution.

[0263] While various modifications and alternatives may exist for the methods and apparatus described herein, specific examples have been shown in the accompanying drawings and described in detail herein. Embodiments are not limited to the specific forms or methods disclosed, but are intended to cover modifications, equivalents, and alternatives falling within the spirit and scope of the various examples and embodiments described herein and / or the appended claims. Furthermore, the disclosure of any particular feature, aspect, method, characteristic, feature, quality, attribute, element, etc., related to the examples herein may be applied to all other examples described herein. No method disclosed herein need to be performed in the stated order. Unless otherwise expressly stated or understood in the context, sequential or chronological language, such as “then,” “next,” “after,” “following,” etc., is used generally to promote fluency of text rather than to restrict the order of operations. Thus, some examples may be performed using the sequence of operations described herein, while others may be performed in a different sequence of operations.

[0264] Unless otherwise expressly stated or understood in the context in which they are used, conditional language used herein, such as in particular “may,” “can,” “may,” “for example,” etc., is generally intended to express that certain examples include certain features, elements, and / or states, while other examples do not include these features, elements, and / or states. Therefore, such conditional language is not generally intended to imply that a feature, element, block, and / or state is necessary in any way for one or more examples, or that one or more examples necessarily contain logic for determining whether such features, elements, and / or states are included in a particular example or whether they are performed in any particular example—whether entered or prompted by the author. When an apparatus or method “comprises” or “contains” (the two are interchangeable) certain features or steps, such an apparatus or method may also “consist substantially of these features or steps” if so defined in the claims. When an apparatus or method “comprises” or “contains” (the two are interchangeable) certain features or steps, such an apparatus or method may also “consist of” such features or steps if so identified in the claims.

[0265] The methods disclosed herein may include certain actions taken by practitioners; however, these methods may also include any user or third-party instructions, whether explicit or implicit, regarding those actions. For example, an action such as “locating the device” includes “instructing the device to be located.”

[0266] The scope disclosed herein also covers any and all overlapping, subranges, and combinations thereof. Terms such as “up to,” “at least,” “greater than,” “less than,” “between,” etc., encompass the stated numerical values. Numerical values ​​beginning with terms such as “about” or “approximately” encompass the stated numerical values ​​and should be interpreted on a case-by-case basis (e.g., as reasonably accurate as possible in the case, such as ±5%, ±10%, ±15%, etc.). For example, “about 4 inches” encompasses “4 inches.” Phrases beginning with terms such as “basic” encompass the stated phrase and should be interpreted on a case-by-case basis (e.g., as reasonably accurate as possible in the case). For example, “basically linear” encompasses “linear.” Unless otherwise stated, all measurements are performed under standard conditions, including temperature and pressure. The phrase “at least one” is intended to require at least one item in the following list, rather than a type of each item in each of the following lists. For example, “at least one of A, B, and C” can include A; B; C; A and B; A and C; B and C; or A, B, and C.

Claims

1. A no-flush intravascular ultrasound (IVUS) catheter, comprising: an imaging core comprising a rotating ultrasound transducer connected to a drive shaft, wherein the drive shaft comprises a coil, a flexible elongated member comprising a sealed internal lumen, wherein the sealed internal lumen is an imaging lumen, wherein the sealed internal lumen is configured to receive the imaging core with the rotating ultrasound transducer and an acoustic coupling medium, wherein the sealed internal lumen comprises a proximal end, a distal end, and a flexible wall extending a length between the proximal end and the distal end, a rigid connector hub comprising an internal chamber, an acoustic coupling medium fill port, a distal interface, a proximal interface, and a flexible seal, wherein the acoustic coupling medium fill port is configured for insertion of an acoustic coupling medium into the rigid connector hub to fill the sealed internal lumen, wherein the distal interface is configured to connect to the proximal end of the sealed internal lumen, wherein the proximal end of the sealed internal lumen is configured to attach to the rigid connector hub, wherein the proximal interface is configured for connection to a catheter interface module, wherein the catheter interface module comprises a motor and is configured to electrically connect with a control console, wherein the control console is configured for controlling rotational actuation of the drive shaft, wherein the flexible seal is connected distally to a sealed housing that connects with the proximal interface, wherein the flexible seal is connected proximally to the internal chamber of the rigid connector hub; wherein the drive shaft extends distally through the flexible seal, wherein the sealed internal lumen is configured for sealed acoustic coupling medium communication with the flexible seal and the internal chamber.

2. The no-flush IVUS catheter of claim 1, wherein the sealed housing is bonded to the rigid connector hub.

3. The no-flush IVUS catheter of claim 1, wherein the sealed housing is bonded to the rigid connector hub through a sealed port.

4. The no-flush IVUS catheter of claim 1, further comprising a second sealed housing, wherein the second sealed housing is attached to the proximal interface.

5. The no-flush IVUS catheter of claim 1, wherein the proximal end of the sealed internal lumen comprises a proximal connector strain relief configured to connect to the rigid connector hub.

6. The no-flush IVUS catheter of any of claims 1-5, wherein the drive shaft is rotationally actuated by an actuator proximal to the proximal interface.

7. The no-flush IVUS catheter of any of claims 1-5, wherein the acoustic coupling medium fill port is configured to seal after delivery of the acoustic coupling medium.

8. The no-flush IVUS catheter of any of claims 1-5, wherein the distal end of the sealed internal lumen comprises a distal port.

9. The no-flush IVUS catheter of claim 8, wherein the distal port is sealed after an acoustic coupling medium fill procedure, wherein the distal port is configured as an exit port to allow the acoustic coupling medium and air bubbles to exit the sealed internal lumen.

10. The no-flush IVUS catheter of claim 8, wherein the distal port is sealed by heat.

11. The no-flush IVUS catheter of claim 8, wherein the distal port is sealed by adhesive.

12. The no-flush IVUS catheter of any one of claims 1-5, for use in combination with at least one of: an X-ray device and an external ultrasound device.

13. The no-flush IVUS catheter of any one of claims 1-5, for use in performing edge-based machine learning computations related to images or image analysis using artificial intelligence algorithms to identify one or more of tissue borders, plaque, calcium, thrombus, dissections, and / or stent apposition.

14. A no-flush intravascular ultrasound (IVUS) catheter, comprising: an imaging core comprising a rotating ultrasound transducer connected to a drive shaft, an elongated member comprising an imaging lumen, wherein the imaging lumen is configured to receive the imaging core with the rotating ultrasound transducer and an acoustic coupling medium, wherein the imaging lumen comprises a proximal end, a distal end, and a wall extending a length between the proximal end and the distal end, a rigid connector hub comprising an internal chamber, an acoustic coupling medium fill port, a distal interface, a proximal interface, and a flexible seal, wherein the acoustic coupling medium fill port is configured for insertion of acoustic coupling medium into the rigid connector hub to fill the imaging lumen; wherein the distal interface is configured for connection to the proximal end of the imaging lumen; wherein the proximal end of the imaging lumen is configured to attach to the rigid connector hub; wherein the proximal interface is configured for connection to an interface module, wherein the interface module comprises a motor, wherein the flexible seal is connected to a sealed housing connected to the proximal interface, wherein the flexible seal is connected to the internal chamber of the rigid connector hub; wherein the drive shaft extends distally through the flexible seal.

15. The no-flush IVUS catheter of claim 14, wherein the distal end of the imaging lumen comprises a distal plug.

16. The no-flush IVUS catheter of claim 15, wherein the distal plug is configured to be inserted into the proximal end of the imaging lumen and pulled to the distal end of the imaging lumen by a detachable wire.

17. The no-flush IVUS catheter of claim 15, wherein the distal plug is configured to bond to a portion of the flexible wall proximate to the distal end.

18. The no-flush IVUS catheter of claim 15, wherein the distal plug is a polymer.

19. The no-flush IVUS catheter of claim 15, wherein the distal plug is bonded to a distal port.

20. The no-flush IVUS catheter of claim 15, wherein the distal port is configured to be sealed with the distal plug.

21. The no-flush IVUS catheter of any one of claims 14-20, wherein the acoustic coupling medium is selected from the group consisting of polyethylene glycol (PEG), water, saline, glycerol, and oil.

22. The no-flush IVUS catheter of any of claims 14-20, wherein the motor is configured to be electrically connected with a control console, wherein the control console comprises a processor, wherein the processor is configured to: instruct the motor to rotate the imaging core; instruct the rotating transducer to generate ultrasound signals; receive backscatter signals from the rotating transducer; and generate an ultrasound image based on the backscatter signals.

23. The no-flush IVUS catheter of any of claims 14-20, wherein the imaging core is in mechanical communication with the drive shaft through the catheter interface module.

24. The no-flush IVUS catheter of claim 23, wherein the interface module comprises an actuator configured to rotate the drive shaft.

25. The no-flush IVUS catheter of claim 23, wherein the interface module comprises a transceiver configured to transmit and receive ultrasound pulses.

26. The no-flush IVUS catheter of any of claims 1-5 and 14-20, wherein the IVUS catheter further comprises one or more strain relief components configured to prevent kinking and excessive localized strain in the IVUS catheter.

27. The flush-free IVUS catheter of any of claims 1-5 and 14-20, wherein, the IVUS catheter further comprises a fill port cover configured to seal the acoustic coupling medium into the sealed imaging lumen at the acoustic coupling medium fill port.

28. The no-flush IVUS catheter of any of claims 1-5 and 14-20, wherein the IVUS catheter further comprises a fill port valve cover, wherein the fill port valve cover comprises an open configuration for filling the acoustic coupling medium, and wherein the fill port valve cover comprises sealing the acoustic coupling medium into the sealed imaging lumen at the acoustic coupling medium fill port.

29. The flush-free IVUS catheter of any of claims 1-5 and 14-20, wherein, the IVUS catheter further comprises a fill port cover configured to insert and seal a fill port cap or fill port valve cover.

30. The no-flush IVUS catheter of any of claims 1-5 and 14-20, wherein the rigid connector hub further comprises a drive bushing disposed about the drive shaft.

31. The no-flush IVUS catheter of any of claims 1-5 and 14-20, further comprising one or more apertures disposed on the drive shaft, the one or more apertures configured to allow the acoustic coupling medium and air bubbles to flow through the drive shaft.

32. The no-flush IVUS catheter of any of claims 1-5 and 14-20, wherein a portion of the sealed inner lumen comprises a substantially uniform wall thickness forming an acoustic window about the rotating ultrasound transducer.

33. A no-flush intravascular ultrasound (IVUS) catheter, comprising: an imaging core comprising a rotating ultrasound transducer connected to a drive shaft, a flexible elongate member comprising a sealed imaging lumen, wherein the sealed imaging lumen is configured to receive the imaging core with the rotating ultrasound transducer and an acoustic coupling medium, wherein the sealed imaging lumen comprises a proximal end, a distal end, and a flexible wall extending a length between the proximal end and the distal end, wherein the distal end comprises a distal port and a distal plug; a rigid connector hub comprising an internal chamber, an acoustic coupling medium fill port, a distal interface, a proximal interface, and a flexible seal, wherein the acoustic coupling medium fill port is configured for insertion of the acoustic coupling medium into the rigid connector hub to fill the sealed imaging lumen; wherein the distal interface is configured for connection to the proximal end of the sealed imaging lumen; wherein the proximal interface is configured for connection to a catheter interface module, wherein the catheter interface module comprises a motor and is configured for electrical connection to a control console, wherein the control console is configured for controlling rotational actuation of the drive shaft, wherein the flexible seal is connected distally to a sealed housing connected to the proximal interface, wherein the flexible seal is connected proximally to the internal chamber of the rigid connector hub; wherein the drive shaft extends distally through the flexible seal, wherein the sealed imaging lumen is in sealed acoustic coupling medium communication with the flexible seal, the internal chamber, and the distal plug.

34. The no-flush IVUS catheter of claim 33, wherein the acoustic coupling medium is selected from the group consisting of: polyethylene glycol (PEG), water, saline, and glycerol.

35. The no-flush IVUS catheter of claim 33, wherein the control console comprises a processor, wherein the processor is configured to: instruct the actuator to rotate the imaging core; instruct the rotational transducer to generate ultrasound signals; receive backscatter signals from the rotational transducer; and generate an ultrasound image based on the backscatter signals.

36. The no-flush IVUS catheter of claim 33, wherein the imaging core is in mechanical communication with the drive shaft through the catheter interface module.

37. The no-flush IVUS catheter of claim 33, wherein the catheter interface module comprises an actuator configured to rotate the drive shaft.

38. The no-flush IVUS catheter of claim 33, wherein the catheter interface module comprises a transceiver configured to transmit and receive ultrasound pulses.

39. The no-flush IVUS catheter of any one of claims 33-38, wherein the IVUS catheter further comprises one or more strain relief components configured to prevent kinking and excessive localized strain in the IVUS catheter.

40. The no-flush IVUS catheter of any one of claims 33-38, wherein the IVUS catheter further comprises a fill port cap configured to seal the acoustic coupling medium into the sealed imaging lumen at the acoustic coupling medium fill port.

41. The no-flush IVUS catheter of any of claims 33-38, wherein the IVUS catheter further comprises a fill port valve cover, wherein the fill port valve cover comprises an open configuration for filling the acoustic coupling medium, and wherein the fill port valve cover comprises sealing the acoustic coupling medium into the sealed imaging lumen at the acoustic coupling medium fill port.

42. The no-flush IVUS catheter of any of claims 33-38, wherein the IVUS catheter further comprises a fill port cap configured to be inserted and seal the fill port cover or fill port valve cover.

43. The flush-free IVUS catheter of any of claims 33-38, wherein, The rigid connector hub further comprises a drive bushing disposed about the drive shaft.

44. The no-flush IVUS catheter of any of claims 33-38, further comprising one or more apertures disposed on the drive shaft, the one or more apertures configured to allow the acoustic coupling medium and air bubbles to flow through the drive shaft.

45. The no-flush IVUS catheter of any of claims 33-38, wherein a portion of the sealed imaging lumen comprises a substantially uniform wall thickness forming an acoustic window about the rotating ultrasound transducer.

46. An intravascular ultrasound (IVUS) catheter, comprising: an ultrasound transducer connected to a drive shaft, wherein the drive shaft comprises a coil, an elongated member comprising a sealed lumen, wherein the sealed lumen is configured to receive the ultrasound transducer and an acoustic coupling medium, wherein the sealed lumen comprises a proximal end, a distal end, and a wall extending a length between the proximal end and the distal end, a rigid connector hub comprising an internal chamber, an acoustic coupling medium fill port, a distal interface, a proximal interface, and a seal, wherein the acoustic coupling medium fill port is configured for insertion of the acoustic coupling medium into the rigid connector hub to fill the sealed lumen; wherein the distal interface is configured for connection to the sealed lumen; wherein the proximal interface is configured for connection to a catheter interface module, wherein the catheter interface module is configured for rotating the drive shaft by an actuator, wherein the catheter interface module comprises a transceiver configured to transmit and receive ultrasound pulses, wherein the seal is connected distally to a sealed housing connected with the proximal interface, wherein the seal is connected proximally to the internal chamber of the rigid connector hub; wherein the drive shaft extends distally through the seal, wherein the sealed lumen is in sealed acoustic coupling medium communication with the seal, the internal chamber, and the distal end.

47. A catheter, comprising: an ultrasound transducer connected to a drive cable, an elongated member comprising a lumen, wherein the lumen is configured to receive the ultrasound transducer and an acoustic coupling medium, wherein the lumen comprises a proximal end, a distal end, and a wall extending a length between the proximal end and the distal end, a rigid connector hub comprising an internal chamber, a distal interface, a proximal interface, and a seal, wherein the distal interface is configured for connection to the lumen; wherein the seal is connected distally to a sealed housing connected with the proximal interface, wherein the seal is proximally connected to an internal chamber of the rigid connector hub; wherein the drive cable extends distally through the seal, wherein the lumen is in sealed acoustic coupling medium communication with the seal, the internal chamber, and the distal end.

48. A method of filling an intravascular ultrasound (IVUS) catheter with an acoustic coupling medium, the method comprising: connecting a source of acoustic coupling medium to an intravascular ultrasound (IVUS) catheter, wherein the IVUS catheter comprises a flexible elongate member and a rigid connector hub, wherein the rigid connector hub comprises an inlet port and an internal chamber, wherein the flexible elongate member comprises an internal lumen, an ultrasound imaging core, and an outlet port; filling the internal lumen with the acoustic coupling medium through the inlet port; expressing a portion of the acoustic coupling medium through the outlet port; sealing the outlet port; and sealing the inlet port.

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

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

51. The method of claim 48, wherein, filling the internal lumen with the acoustic coupling medium comprises pushing the acoustic coupling medium into the internal lumen with positive pressure at the inlet port.

52. The method of claim 48, wherein a pump is configured to push the acoustic coupling medium into the internal lumen with positive pressure at the inlet port.

53. The method of claim 48, wherein filling the internal lumen with the acoustic coupling medium comprises pulling the acoustic coupling medium into the internal lumen with vacuum pressure at the outlet port.

54. The method of claim 48, wherein, the ultrasound imaging core is located in the internal lumen of the flexible elongate member, wherein the ultrasound imaging core comprises a rotating ultrasound transducer connected to a distal end of a drive shaft, wherein the outlet port is located at a distal end of the internal lumen, wherein the rigid connector hub further comprises a distal interface connected to a proximal end of the internal lumen.

55. The method of claim 48, wherein sealing the outlet port comprises heating a plug at the outlet port.

56. The method of claim 48, wherein sealing the outlet port comprises adhering a plug at the outlet port.

57. The method of any of claims 48-56, wherein, the rigid connector hub further comprises a proximal interface having a flexible seal, wherein the flexible seal is configured to seal a portion of a drive shaft extending therethrough, wherein the proximal interface is configured to connect to a control console, wherein the control console is configured for rotational actuation of the drive shaft.

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

59. The method of any of claims 48-56, wherein the acoustic coupling medium is selected from the group consisting of: polyethylene glycol (PEG), water, saline, glycerol, and oil.

60. The method of any of claims 48-56, further comprising adding a colorant to the acoustic coupling medium.

61. The method of any of claims 48-56, further comprising mechanically agitating the ultrasound imaging core of the IVUS catheter.

62. The method of claim 61, wherein, Mechanically agitating the ultrasound imaging core comprises rotating the ultrasound imaging core.

63. The method of any of claims 48-56, further comprising orienting the IVUS catheter to a horizontal superior positive angle.

64. The method of any of claims 48-56, wherein the sealing the exit port comprises sealing a polymer plug at the exit port.

65. A method of filling a catheter with an acoustic coupling medium, the method comprising: providing a catheter, wherein the catheter comprises a flexible elongate member and a rigid connector hub, wherein the rigid connector hub comprises an entry port and an internal chamber, wherein the flexible elongate member comprises an internal lumen, an ultrasound imaging core, and an exit port; filling the internal lumen with an acoustic coupling medium through the entry port; expressing a portion of the acoustic coupling medium through the exit port; sealing the exit port with a plug; and sealing the entry port.

66. A method of filling an ultrasound device with an acoustic coupling medium, the method comprising: connecting a source of acoustic coupling medium to the ultrasound device, wherein the ultrasound device comprises a flexible elongate member and a rigid connector hub, wherein the rigid connector hub comprises an entry port and an internal chamber, wherein the flexible elongate member comprises an internal lumen and an ultrasound imaging core; filling the internal lumen with an acoustic coupling medium through the entry port; and sealing the entry port.

67. The method of any of claims 65-66, further comprising maintaining the acoustic coupling medium in a surrounding environment for a first period of time.

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

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

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

71. The method of claim 70, wherein the second period of time is between about 30 minutes and about 120 minutes.

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

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

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

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

76. The method of claim 65, further comprising placing the catheter on a catheter warming plate.

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

78. The method of any one of claims 65-66, further comprising placing the acoustic coupling medium in a syringe and inserting the acoustic coupling medium into the internal lumen via a syringe pump device.

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

80. The method of claim 79, wherein the target delivery rate is between 0.1 mL / min and 1.0 mL / min.

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

82. The method of claim 81, wherein the target temperature is between 35 °C and 80 °C.

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

84. The method of any one of claims 78-82, wherein, the syringe pump device further comprises a rotary motor configured to rotate the imaging mandrel to agitate and remove air from the sealed internal imaging lumen.

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

86. The method of claim 85, wherein the target speed is based on one or more of: an internal pressure of the syringe pump device and an internal pressure of the sealed internal lumen.

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

88. The method of claim 87, wherein the pressure threshold is between 50 psi and 150 psi.

89. The method of claim 85, wherein the target speed is between 900-1100 rpm.

90. A degassing system, comprising: 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 reservoir configured to receive a degassed acoustic coupling medium, wherein the acoustic coupling medium is maintained in the container at ambient environment for a first period of time, wherein the vacuum pump is arranged to be in fluid communication with the container and configured to maintain the container at a vacuum pressure for a second period of time to transform the acoustic coupling medium into a degassed acoustic coupling medium.

91. The degassing system of claim 90, wherein the first period of time is between 30 minutes and 300 minutes.

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

93. The degassing system of claim 90, wherein the second period of time is between 30 minutes and 120 minutes. ​ 94. The degassing system of claim 90, wherein the second time period continues until the acoustic coupling medium reaches a desaturation threshold.

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

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

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

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

99. The degassing system of claim 98, wherein during one or more of the first time period and the second time period, the magnetic stir bar is placed in the acoustic coupling medium, and wherein the magnetic stirring mechanism is configured to generate a magnetic field to spin the magnetic stir bar, stirring the acoustic coupling medium.

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

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

102. A system for filling an IVUS catheter, the system comprising: a catheter hot plate configured to receive the IVUS catheter therein and heat the IVUS catheter to a target catheter temperature; a syringe pump configured to: receive at least one syringe containing an acoustic coupling medium; expel the acoustic coupling medium from the at least one syringe at a target delivery rate; a syringe heating assembly configured to maintain the at least one syringe at a target syringe temperature; a rotation motor configured to rotate an imaging core to agitate and remove air from an imaging lumen of the IVUS catheter.

103. The system of claim 102, wherein the target catheter temperature is between 35 °C and 80 °C.

104. The system of claim 102, wherein the target delivery rate is between 0.1 mL / min and 1.0 mL / min.

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

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

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

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

109. The system of claim 108, wherein the pressure threshold is between 40 psi and 120 psi.

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

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

112. A catheter heating apparatus, comprising: an insulation layer; a heating layer disposed above the insulation layer, the heating layer configured to heat an IVUS catheter to a target temperature; a catheter receiving layer disposed above the heating element, the catheter receiving layer comprising a catheter cutout configured to receive the IVUS catheter; and a cover layer disposed above the catheter receiving layer.

113. The catheter heating apparatus of claim 112, wherein the target temperature is between at least about 35 °C and at least about 80 °C.

114. The catheter heating apparatus of claim 112, wherein the shape of the catheter cutout is one of an "S" shape, a spiral shape, or a straight shape.

115. The catheter heating apparatus of claim 112, wherein the shape of the catheter cutout is based on one or more properties of the IVUS catheter.

116. The catheter heating apparatus of any 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 apparatus of any of claims 112 to 115, wherein, the catheter receiving layer comprises aluminum.

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

119. A no-rinse intravascular ultrasound (IVUS) catheter, comprising: an imaging core comprising a rotating ultrasound transducer disposed within a transducer housing, the transducer housing connected to a distal end of a drive shaft by a coupler, a flexible elongate member comprising a sealed imaging lumen, wherein the sealed imaging lumen is configured to receive the rotating ultrasound transducer and an acoustic coupling medium, wherein the sealed imaging lumen comprises a proximal end, a distal end, and a flexible wall extending a length between the proximal end and the distal end, wherein the distal end comprises a distal port and a distal plug; a rigid connector hub comprising an internal chamber, an acoustic coupling medium fill port, a distal interface, a proximal interface, and a flexible seal, one or more apertures disposed on one or more of the transducer housing, the coupler, and the drive shaft, the one or more apertures configured to allow the acoustic coupling medium and gas bubbles to flow through one or more of the transducer housing, the coupler, and the drive shaft; wherein the acoustic coupling medium fill port is configured for insertion of the acoustic coupling medium into the rigid connector hub to fill the sealed imaging lumen; wherein the proximal interface is configured to connect to a console, wherein the console is configured to control rotational actuation of the drive shaft, wherein the proximal interface is configured for connection to a catheter interface module, wherein the catheter interface module is configured for rotating the drive shaft by an actuator, wherein the catheter interface module comprises a transceiver configured for transmitting and receiving ultrasound pulses, wherein the flexible seal is connected distally to a seal housing connected to the proximal interface, wherein the flexible seal is connected proximally to the internal chamber of the rigid connector hub; wherein the drive shaft extends distally through the flexible seal, wherein the sealed imaging lumen is in sealed acoustic coupling medium communication with the flexible seal, the internal chamber, and the distal plug.

120. A kit comprising one or more of the catheter, hub, seal, plug described herein and instructions for use.

121. Using any of the devices, systems and methods of any of the preceding claims for imaging without any therapy.

122. Using any of the devices, systems and methods of any of the preceding claims for imaging before, after and / or simultaneously with ultrasound as therapy on the same or different system.

123. Using any of the devices, systems and methods of any of the preceding claims wherein the term "IVUS catheter" is replaced with an ultrasound imaging device and such device is used for imaging non-vascular lumens, cavities or organs.

124. Using any of the devices, systems and methods of any of the preceding claims such that the processor performs edge-based machine learning calculations related to the images.

125. Using any of the devices, systems and methods of any of the preceding claims configured for image analysis using artificial intelligence algorithms to identify one or more of tissue borders, plaque, calcium, thrombus, dissection and / or stent apposition.

126. Using any of the devices, systems and methods of any of the preceding claims for imaging before, after and / or simultaneously with non-ultrasound techniques as therapy, wherein the non-ultrasound techniques include mechanical thrombectomy and / or interventional coronary procedures.

127. Using any of the devices, systems and methods of any of the preceding claims for minimally invasive imaging.

128. Using any of the devices, systems and methods of any of the preceding claims for imaging intravascular tissue to identify irregularities, disease and / or lesions for medical treatment.

129. Using any of the devices, systems and methods of any of the preceding claims to identify lesions, plaque, thrombus, calcium buildup, dissections and to measure these abnormalities.

130. An ultrasound transducer having one or more features described in the foregoing description.

131. A method of ultrasound imaging having one or more features described in the foregoing description.

132. A method of manufacturing devices and systems having one or more features described in the foregoing description.

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