Intravascular imaging system and method

Abstract

A system for intravascular imaging includes a first flexible elongated instrument including an imaging transducer configured for rotation within the first flexible elongated instrument, and a sensing element including a sensor configured to detect position information encoding of a second flexible elongate instrument. The sensing element is fixedly engaged with the first flexible elongated instrument to place the sensor at a defined distance from the imaging transducer and enable the sensing element to move together with the first flexible elongated element in a body lumen. A rotational drive device includes a coupling element configured to couple to the first flexible elongated instrument and enable the rotational drive device to drive the imaging transducer in rotation. The rotational drive device is configured to receive imaging signals from the imaging transducer and obtain signals from the sensor when the coupling element is coupled to the first flexible elongated element.

Description

Intravascular Imaging System and MethodRELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 519,921, filed on August 16, 2023. The entire teachings of the above application are incorporated herein by reference.BACKGROUND

[0002] Intracoronary imaging is often used to accurately measure vessel and stenosis dimensions, assess vessel integrity, characterize lesion morphology and aide in body lumen procedures, including percutaneous coronary intervention (PCI) procedures. The frequency of complex percutaneous coronary interventions has steadily increased in recent years due to clinical benefits provided by the interventions, which can increase the life expectancy and quality of life for patients suffering from endovascular neurosurgical, cardiovascular, and peripheral artery diseases. Various diagnostic and therapeutic medical devices (e.g., guidewires, balloons, atherectomy, lithotripsy, stents, imaging and physiology diagnostic modalities, X-ray angiography, and fluoroscopy) enable radiologists, cardiologists, and vascular specialists to visualize a patient’s intra-vasculature to guide treatment decisions and to perform intervention procedures. Often, X-ray fluoroscopy with contrast injection is used to guide physicians to position devices (e.g., stents, guidewires, and balloons) toward targeted lesion locations along a guidewire within the endo-vasculature.

[0003] In a PCI procedure, vascular access is typically gained through an arterial entry point, such as the radial, brachial, or femoral artery, or through a venous puncture. From the entry point, a physician can access the vasculature of organs such as heart, lungs, kidneys, and brain by advancing a guidewire into the patient until a distal end of the guidewire crosses, for example, a lesion to be treated. After the guidewire position is finalized and situated such that it is viewable on an angiographic image, a desired therapeutic and / or diagnostic device is mounted on a proximal end of the guidewire. The therapeutic and / or diagnostic device is then advanced towards the distal end to the feature of interest.

[0004] Depending upon the clinical situation, imaging and / or physiological probes, such as Intravascular Ultrasound (IVUS), Optical coherence tomography (OCT) and Fractional Flow Reserve (FFR) devices, can be used for pre-intervention assessment, such as fordetermining lesion location, lesion dimension, plaque morphology, and coronary pressure at an area of interest. Endoluminal diagnostic modalities, such as IVUS, OCT, and FFR, which can generate more detailed vessel lumen information than that which can be obtained from X- ray imaging alone, are widely used for minimally invasive PCI procedures. Percutaneous coronary IVUS is typically performed with a rotational IVUS catheter or a phased array IVUS catheter.

[0005] Upon diagnostic assessment, interventional devices may then be guided to an area in need of treatment, which can require guidance by fluoroscopic imaging. Positioning of an interventional device at a location identifiable on a diagnostic dataset can be difficult.SUMMARY

[0006] Systems and methods are provided that can enable improved intravascular imaging with precision position detection of one or more flexible elongate instruments disposed within a body lumen, including improved detection of a position within a body lumen at which a diagnostic scan is performed, at which a therapy is delivered, or combinations thereof.

[0007] A system for intravascular imaging includes a first flexible elongated instrument including an imaging transducer configured for rotation within the first flexible elongated instrument. The system includes a sensing element including a sensor configured to detect position information encoding of a second flexible elongate instrument disposed in a body lumen. The sensing element is fixedly engaged with the first flexible elongated instrument to enable the sensing element to move together with the first flexible elongated element in the body lumen and optionally to place the sensor at a defined distance from the imaging transducer. The system includes a rotational drive device including a coupling element. The coupling element is configured to couple to the first flexible elongated instrument and enable the rotational drive device to drive the imaging transducer in rotation. The rotational drive device is configured to receive imaging signals from the imaging transducer and obtain signals from the sensor when the coupling element is coupled to the first flexible elongated element.

[0008] The system can include a controller that is configured to measure relative displacement of the first and second flexible elongate instruments based on the signals obtained from a sensor, such as the sensor of the sensing element. The controller can beconfigured to translate the obtained signals to code characters and determine a position of one of the first and second flexible elongated instruments based on the code characters.

[0009] The rotational drive device can include a motor to drive the imaging transducer in rotation, and the controller can be configured to control the motor.

[0010] The coupling element of the rotational drive device can include a mechanical interface configured to mechanically link to the imaging transducer. The coupling element can include an electronic interface configured to receive identification information from the first flexible elongated element.

[0011] The rotational drive device can include a system connector for transmitting a signal indicative of the detected position information encoding (e.g., location information encoding) to a signal processing and display system. The system connector can include an interface for transmitting identification information of the sensing element to the signal processing and display system. The system connector can include an interface for bidirectional communication with the signal processing and display system. Such interface for bi-directional communication can be a wired interface, a wireless interface, or a combination thereof.

[0012] The sensor of the sensing element can be an optical reader. For example, the signal from the sensor can be an optical signal transmitted through at least one optical fiber.

[0013] The first flexible elongated instrument can include a guide rail to guide movement of the first flexible elongated instrument. For example, the guide rail can have two parts, a distal part positioned between the imaging transducer and a distal end of the first flexible elongated instrument, and a proximal part positioned between the imaging transducer and a proximal end of the first flexible elongated instrument.

[0014] The second flexible elongated instrument can be a guidewire having position encoding markers.

[0015] The system can include a localization sensor or marker for spatial alignment of at least a subset of the position encoding markers to a position defined in both a coordinate frame of reference of the system and a coordinate frame of reference of another modality. For example, the localization marker can include at least one imaging marker, such as a radiopaque imaging marker. The at least one imaging marker can include at least one radiopaque marker positioned at the guidewire at a defined distance from the position encoding markers of the guidewire. In addition, the sensor of the sensing element can be placed at a defined distance from the imaging transducer.

[0016] A method of intravascular imaging includes receiving imaging signals from an imaging transducer configured for rotation within a first flexible elongated instrument. While moving the first flexible elongated instrument relative to a second flexible elongated instrument disposed in a body lumen, relative displacement between the first and second flexible elongated instruments can be determined using a sensing element. The sensing element can be fixedly engaged with the first flexible elongated instrument and include a sensor configured to detect position information encoding, e.g., position information encoding of the second flexible elongated instrument. The sensor can be positioned at a defined distance from the imaging transducer.

[0017] The method can include driving rotational motion of the imaging transducer with a rotational drive device, which can include a motor drive.

[0018] The method can further include, with the sensor, reading encoding markers on the second flexible elongated instrument.

[0019] The method can include guiding movement of the first flexible elongated instrument relative to the second flexible elongated instrument using a guide rail having two parts, a distal part positioned between the imaging transducer and a distal end of the first flexible elongated instrument, and a proximal part positioned between the imaging transducer and a proximal end of the first flexible elongated instrument.

[0020] The method can further include coupling a coupling element of a rotational drive device to the first flexible elongated instrument, the coupling element enabling the rotational drive device to drive the imaging transducer in rotation. The rotational drive device can be configured to receive imaging signals from the imaging transducer and obtain signals from the sensor when the coupling element is coupled to the first flexible elongated element.

[0021] The coupling element can include a mechanical interface configured to mechanically link to the imaging transducer, an electronic interface configured to receive identification information from the first flexible elongated element, or both a mechanical interface and an electronic interface.BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The foregoing will be apparent from the following more particular description of example embodiments, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments.

[0023] FIG. 1 A illustrates an example Intravascular Ultrasound (IVUS) image obtained using a phased array IVUS imaging catheter.

[0024] FIG. IB illustrates an example IVUS image obtained using a rotational IVUS imaging catheter.

[0025] FIG. 2 is a schematic diagram illustrating intravascular imaging using an automatic pullback system.

[0026] FIG. 3 A is a schematic diagram illustrating an intravascular imaging system for manual translation / pullback according to an example embodiment of the invention.

[0027] FIG. 3B illustrates coupling of a rotational drive device to an imaging catheter hub according to an example embodiment of the invention.

[0028] FIG. 4 is a schematic diagram illustrating an intravascular imaging system including an imaging catheter, a position sensing element, and a rotational drive device according to an example embodiment of the invention.

[0029] FIG. 5 is a schematic diagram illustrating an intravascular imaging system according to another example embodiment of the invention.

[0030] FIG. 6 is a block diagram of a co-location system and communication overview.

[0031] FIG. 7 is a schematic diagram illustrating example position data being coregistered (correlated) with imaging modalities via a reference integration system.

[0032] FIG. 8 is a diagram illustrating example coordinate frames of reference and registration of a device location within the coordinate frames utilizing an imaging-visible marker.

[0033] FIG. 9 illustrates an example pin configuration for use with a rotational drive connector.DETAILED DESCRIPTION

[0034] A description of example embodiments follows.

[0035] Examples of systems and methods providing for position detection of endoluminal instruments are described in International Application No. PCT / US2021 / 072780, titled “Methods and Systems for Body Lumen Medical Device Location,” published as International Publication No. WO 2022 / 126101 A2, the entire teachings of which are incorporated herein by reference.

[0036] Examples of systems, devices, and methods for measuring relative displacement between at least two flexible elongate instruments within a body lumen are described inIntemational Application No. PCT / US2023 / 064168, titled “Devices and Methods for Endoluminal Position Detection” published as International Publication No. WO 2023 / 173108 Al, the entire teachings of which are incorporated herein by reference. The provided systems, devices, and methods can use two detectors (e.g., encoding sensors) and can enable improved position detection, including orientation and direction detection, of flexible elongate instruments disposed within a body lumen.

[0037] Examples of systems and methods for improved detection of a position within a body lumen at which a therapy is delivered and improved labelling of patent data sets of treatment delivery locations with respect to anatomical date are described in International Application No. PCT / US2023 / 067851, titled “Systems and Methods for Endoluminal Tracking with Therapeutic Delivery Sensing” published as International Publication No. WO 2023 / 235854 Al, the entire teachings of which are incorporated herein by reference.

[0038] The example devices, systems and methods described herein are generally described within the context of percutaneous coronary intervention (PCI) procedures; however, the provided devices and systems can be applied to or used within the context of other types of endoluminal procedures, such as gastrointestinal procedures.

[0039] The accompanying figures illustrate, and the associated description set forth improvements to the systems, devices, and methods provided in WO 2022 / 126101 A2.

[0040] Intravascular ultrasound (IVUS) is typically performed with either phased array or rotational imaging catheters. Illustrated in FIG. 1 A is an example IVUS image 102 obtained using a phased array IVUS imaging catheter. Illustrated in FIG. IB is an example IVUS image 104 obtained using a rotational IVUS imaging catheter. The image quality is markedly superior with high-definition rotational catheters, as is evident from the images 102 and 104 in FIGS. 1 A and IB, respectively. In addition, rotational IVUS typically provides precise distance information. Yet phased array constitutes 80% of the US market for IVUS catheters because phased array catheters are easy to use, allow for manual advancement and pullback, and require no moving parts or flushing.

[0041] In contrast, rotational IVUS requires an electro-mechanical device called a motor drive which needs to be covered with a sterile bag and attached to a large pullback sled during a PCI procedure. The catheter is then inserted into the motor drive connector and flushed. The motor drive is moved to the most forward position until the catheter’s telescope is fully retrieved, and then the pullback button is pressed to start imaging. Motorizedpullback typically occurs at speeds of 0.5 mm / s to 1.0 mm / s, requiring 90-180 seconds to image the entire vessel. Faster pullback speeds, e.g., up to 40mm / s, may be used.

[0042] A motor drive is an electromechanical device that interfaces with rotational imaging catheters. It provides two types of controlled motion for intravascular imaging devices / transducers such as IVUS, OCT, and NIRS: The motor drive (1) rotates the catheter imaging transducer at certain rotational speeds, and (2) provides the catheter imaging transducer pullback via a mechanical pullback device commonly known as a ‘sled.’ The motor drive’s electronics transmit ultrasound pulses and receive ultrasound echoes. It can acquire the imaging transducer rotational data and identify the imaging catheter parameters. It also contains electronics associated with the control of the pullback sled motor and user interface circuitry.

[0043] The typical range of linear movement speed for the pullback sled can include speeds of, for example, 0.5 mm / s, 1.0 mm / s, 2.0mm / s, . . ., 20mm / s, and 40mm / s. A user typically selects the speed via the motor drive or the system console.

[0044] FIG. 2 is a schematic diagram illustrating an automatic pullback system 200 for intravascular imaging, which includes an automatic pullback motor drive 204, also referred to as a motor drive unit (MDU). The pullback drive device 204 connects to the imaging catheter 202, for example, via a connector socket 206. A rotational transformer 208 provides patient isolation 210 from the rotating motor 212 that drives the imaging transducer 203 of the catheter 202 via connector socket 206. The drive device 204 includes transmitter / receiver (Tx / Rx) electronics 214 which communicate with the rotating motor 212 and, via elements 206, 208, and 210, also with the imaging transducer 203, to receive imaging information from the imaging transducer 203. Connector 216 allows the drive device 204 to couple to and communicate with an external system 226 for processing and displaying imaging data from IVUS, OCT, and other imaging modalities. The connector 216 also communicates with signal control electronics 222, which in turn communicate with encoder 220 that communicates with pullback motor 218. The connector 216 also communicates with auto pullback device 224 of pullback drive device 204.

[0045] Typical IVUS imaging catheter devices that use a rotational imaging sensor include a telescope device or telescope portion, which is fixed to an automatic pullback drive device, such as the pullback device 204 illustrated schematically in FIG. 2. The telescope portion is attached to the sled of the pullback drive device, which remains stationary. The motor drive of the pullback drive device 204 is mechanically connected to the imaging core(not shown in FIG. 2) positioned within the imaging catheter 202. A pullback motor 218 of the drive device 204 pulls the imaging core back, thereby pulling back (e.g., translating) the imaging sensor (e.g., imaging transducer) 203 within the catheter. The imaging sensor 203 is also rotating while imaging the vessel, the rotating motion being provided by a rotation motor 212 of the drive device. The motor is typically mechanically coupled to the imaging core that carries the imaging sensor at its distal end.

[0046] In use, the automatic pullback motor drive device 204 must be enclosed in a bag, e.g., to maintain a sterile operating field. The bag, however, is cumbersome to apply and can cause problems, as it can get caught in gears that provide translation of the motor drive device relative to the sled. In the present approach, there is no need for translation of a motor drive relative to a sled. Furthermore, devices according to the present approach can be made smaller, which reduces the size of any bag that may be needed, possibly even removing the need for a bag altogether. This can also make the device more reliable and easier to use.

[0047] Typically, the telescope portion and the catheter must be flushed, including during an imaging procedure, to eliminate air bubbles along the path of the translating and rotating imaging sensor within the catheter, as any air bubbles could otherwise degrade image quality. The telescope portion, however, which typically includes several layers (e.g., three layers) of material, is difficult to flush.

[0048] Devices, systems, and methods according to the present approach eliminate the need for a telescope portion, thereby improving ease of use over current rotating sensor IVUS devices. In fact, the ease of use is similar to that experienced when using phased array type imaging sensor device, which do not need flushing. The image quality of devices according to the present approach is expected to be that of existing rotating imaging sensor devices, which provide image quality that is typically better than that of phased array sensors.

[0049] Certain IVUS imaging catheter devices include two guide rails to allow the catheter to be pushed with sufficient force through vessel blockages. These devices do not include a telescope and the imaging sensor does not move axially within the catheter. Also, since there is no pullback mechanism to pull the imaging sensor proximally withing the catheter, no relative displacement or distance information is available to a user. Unlike the current approach, these devices do not have a position sensor at the catheter.

[0050] FIGS. 3 A-3B illustrate an example of a new approach that eliminates the need for bulky motorized pullback devices that are standard with rotational intravascular ultrasound or optical coherence tomography catheters. Using guidewire encoding and sensing,unprecedented distance measurement accuracy is possible with plug and play simplicity, enabling current the combination of high-resolution imaging with the simplicity and speed of manual pullback that operators prefer.

[0051] As illustrated in FIG. 3 A, a system 300 for intravascular imaging includes a first flexible elongated instrument 302 (e.g., an IVUS imaging catheter) which includes an imaging transducer 303 configured for rotation within the first flexible elongated instrument 302. The system includes a sensing element comprising a sensor (e.g., an optical sensor; not shown in FIG. 3A, but see FIG. 4) configured to detect position information encoding (e.g., markers encoding displacement, position, and / or orientation) of a second flexible elongate instrument (e.g., a guidewire; not shown in FIG. 3A, but see FIG. 4) disposed in a body lumen. The sensing element is fixedly engaged with the first flexible elongated instrument 302 to enable the sensing element to move together with the first flexible elongated element in the body lumen. The sensing element can be configured to place the sensor at a defined distance from the imaging transducer 303 (see, e.g., FIG. 4).

[0052] The system 300 includes a rotational drive device 304 that includes a coupling element 306 (e.g., a motor drive connector or connector socket). The coupling element 306 is configured to couple to the first flexible elongated instrument 302 (e.g., the imaging catheter) and enable the rotational drive device 304 to drive the imaging transducer 303 in rotation. The rotational drive device 304 is configured to receive imaging signals from the imaging transducer 303 and obtain signals from the sensor when the rotational drive device 304 is coupled to the first flexible elongated element 302. The system 300 includes, e.g., in the rotational drive device 304, a motor 312 configured to drive the imaging transducer 303 in rotation, e.g., via a mechanical link provided by the coupling element 306. The system 300 also provides for patient isolation 310, e.g., electrical isolation between the catheter 302 and the rotating motor 312 and / or electronics 314 of the drive device 304.

[0053] FIG. 3B illustrates coupling of rotational drive device 304 to a hub 301 of imaging catheter 302. The coupling element 306 of the rotational drive device 304 includes a mechanical interface configured to mechanically link to the imaging transducer 303. The coupling element 306 also includes an electronic interface configured to receive identification information (e.g., a catheter ID) from the first flexible elongated element 302 (e.g., imaging catheter). Typically, the imaging catheter hub includes a flushing port, which is not illustrated here for simplicity.

[0054] As shown in FIG. 3A, the rotational drive device 304 includes a system connector 316 for coupling the device to an external device or system and for transmitting and / or receiving data. The connector 316 can, for example, transmit a signal indicative of the detected position information encoding (e.g., location information encoding) to a signal processing and display system 326. The connector 316 can include an interface 336 for transmitting identification information of the sensing element to the signal processing and display system 326. The interface 336 can allow for bi-directional communication with the signal processing and display system 326. Such interface for bi-directional communication can be a wired interface, a wireless interface, or a combination thereof.

[0055] As further illustrated in FIG. 3A, the drive device 304 includes optical transmitter / receiver electronics 332 to transmit to and receive signals from the catheter 302. Signal control electronics 334 process the signals, which can be communicated to / from system 326 via connector 316 and interface 336. The drive device 304 can include a catheter ID module 330 configured to receive identification information from the imaging catheter 302, which can be processed, for example, by electronics 332, and communicated system 326 via connector 316 and / or interface 336.

[0056] FIG. 4 is a schematic illustration of an example intravascular imaging system. System 400 includes a first flexible elongated instrument 402 (e.g., an IVUS imaging catheter) which includes an imaging transducer 403 configured for rotation within the first flexible elongated instrument 402. The system includes a sensing element 442 (e.g., positioning sensing unit) comprising a sensor (e.g., an optical sensor) configured to detect position information encoding 452 (e.g., markers encoding displacement, position, and / or orientation) of a second flexible elongate instrument 450 (e.g., a guidewire). The sensing element 442 is fixedly engaged with the first flexible elongated instrument 402 to place the sensor at a defined distance DI from the imaging transducer 403. The fixed engagement enables the sensing element 442 to move together with the first flexible elongated element 402 when inserted in a body lumen.

[0057] As illustrated in FIG. 4, system 400 includes a rotational drive device 404 that includes a coupling element 406 (e.g., a motor drive connector). The coupling element 406 is configured to couple to the first flexible elongated instrument 402 (e.g., the imaging catheter) and enable the rotational drive device 404 to drive the imaging transducer 403 in rotation. The rotational drive device 404 is configured to receive imaging signals from the imaging transducer 403 and obtain signals from the sensor when the rotational drive device 404 iscoupled to the first flexible elongated element 402. The rotational drive device 404 includes a motor 412 configured to drive the imaging transducer 403 in rotation via a mechanical link provided by the coupling element 406 and imaging core 405. Patient isolation, e.g., electrical isolation, is provided via a rotating transformer 408 between the connector 406 to catheter 402 and the rotating motor 412 and / or electronics 414 of the drive device 404. The transformer 408 further allows for electrical signal transmission between the elements of the device 404 and elements of the catheter 402 while allowing for the motor 412 to drive the imaging transducer 403 in rotation.

[0058] The rotational drive device 404 includes a connector 416 for coupling the device to an external device or system and for transmitting and / or receiving data. The connector 416 can, for example, transmit a signal indicative of the detected position information encoding (e.g., location information encoding) to a signal processing and display system (e.g., system 326 of FIG. 3 A). The connector 416 can include an interface 436 for transmitting identification information of the sensing element 442 to the signal processing and display system. The interface 436 can allow for bi-directional communication with the signal processing and display system.

[0059] The system 400 includes a controller 448 that is operationally coupled to various elements of drive device 404, including motor 412, transmitter / receiver electronics 414, signal control electronics 434, optical transmitter / receiver electronics 432, timing generator 435, and instrument interface 436. The controller 438 can be configured to measure relative displacement of the first and second flexible elongate instruments, e.g., imaging catheter 402 and guidewire 450, based on the signals obtained from the sensor of the sensing element 442. The controller 448 can be configured to translate the obtained signals to code characters and determine a position of one of the first and second flexible elongated instruments based on the code characters. The controller 448 can be configured to control the motor 412 to drive the imaging transducer 403 in rotation via rotating transformer 408.

[0060] The coupling element 406 of the rotational drive device can include a mechanical interface configured to mechanically link, e.g., via a drive shaft of imaging core 405, to the imaging transducer 403. The coupling element 406 can include an electronic interface configured to receive identification information from the imaging catheter 402, which can be processed by catheter ID module 430.

[0061] The system 400 can include a localization sensor or marker (448, 454) for spatial alignment of at least a subset of the position encoding markers 452 to a position defined inboth a coordinate frame of reference of the system and a coordinate frame of reference of another modality. The localization marker (448, 454) can include at least one imaging marker, such as a radiopaque imaging marker. In the example illustrated in FIG. 4, the localization marker 448 is an imaging marker positioned at a distal end of the imaging catheter 402. As illustrated, the localization marker 454 is an imaging marker of the guidewire 450 and positioned at a defined distance D2 from the position encoding markers 452.

[0062] As illustrated in FIG. 4, the imaging catheter 402 according to the current approach includes a guide rail comprising two parts 444, 446. For example, a distal part 446 of the two-part guide rail is positioned between the imaging transducer 403 and a distal end of the imaging catheter 402, and a proximal part 444 of the two-part guide rail is positioned between the imaging transducer 403 and a proximal end of the imaging catheter 402. An advantage of including a two-part guide rail is that such an arrangement can allow the catheter to be pushed with sufficient force through vessel blockages.

[0063] In the example illustrated in FIG. 4, the positioning sensor unit 442 is part of the catheter 402. As shown, the sensor unit 442 includes an annular sensor within guide rail 444. The imaging device 403 (such as IVUS transducer or OCT transducer) and the sensor of sensor unit 442 move with the catheter 402. Here, the sensor is an optical reader that can detect position encoding 452 of guidewire 450. The signal from the sensor is an optical signal transmitted through at least one optical fiber 440. The position detection principle of the optical reader / sensor can be the same as described, for example, in WO 2022 / 126101 A2 or in WO 2023 / 173108 Al.

[0064] The connector 406 interfaces with the new IVUS catheter 402 and rotational drive device 404. The connector can carry two sets of signals: imaging sensor signals and location sensor signals. The connection mechanism and the (optional) catheter ID feature can be the same as, or similar to, those described elsewhere herein.

[0065] As illustrated in FIG. 5, an example system for intravascular imaging 500 includes an imaging catheter 502, e.g., first flexible elongated instrument, which includes an imaging transducer 503, such as a rotational IVUS transducer that is configured for rotation within the catheter. A sensing element at the catheter 502 comprises a precision positioning sensor 542 (e.g., an optical sensor), which is configured to detect position information encoding (e.g., markers encoding displacement, position, and / or orientation) of a second flexible elongated instrument (e.g., a guidewire; not shown in FIG. 5). The positioning sensor 542 can befixedly engaged with the catheter 502 and, optionally, places the sensor at a defined distance from the imaging transducer 503. Such an arrangement enables the sensor 542 to move together with the catheter 502 when disposed in a body lumen.

[0066] The system 500 includes a rotational drive device 504 that includes an imaging catheter connector 506, e.g., a coupling element, which is configured to couple to the catheter 502, to provide a mechanical and / or electrical link. When coupled, a rotational imaging core motor 512 can drive the imaging transducer 503 in rotation via rotational transformer 508 and rotational imaging core 505. The rotational drive device 504 can be configured to receive imaging signals from the imaging transducer 503 and obtain signals from the sensor 542 when the rotational drive device 504 is coupled to the catheter 502. The imaging signals from catheter 502 pass to a patient isolated transmitter / receiver circuitry 514 which provides image data 515. Positioning sensor data from catheter 502 pass to optical transmitter / receiver circuitry 532 and then to analog conditioning 534. Optionally, catheter identification information 531 passes to catheter ID element 530. A system interface 536, which may include a system connector 516, receives the image data 515, positioning data from analog conditioning 534, data from rotational motor 512, and optional catheter ID data 530. The system interface 526 can be configured for communication with external systems, such as imaging system 526 and reference integration system 527, as further described herein.

[0067] As shown in the example configurations in FIGS. 4 and 5, an imaging catheter can be provided with a position sensing element or reader (e.g., readers as shown in the example devices of FIGS. 12, 13, 14, 15, 32, 35, 36 of Inti. Pub. No. WO 2022 / 126101 A2), which can detect position encoding of another flexible elongate instrument disposed in a body lumen (e.g., a guidewire).

[0068] Flexible elongate instruments can include one or more sensors to detect encoding on other flexible elongate instrument to provide for position information during an endoluminal procedure. A system for intravascular imaging can include a controller that is configured to measure relative displacement of first and second flexible elongate instruments based on signals obtained from a sensor. The controller can be configured to translate the obtained signals to code characters and determine a position of one of the first and second flexible elongated instruments based on the code characters.

[0069] As described in WO 2022 / 126101 A2, absolute position encoding typically uses sequences of code lines of different widths, which are unique for different positions. For example, for a common binary position code, four code characters are needed for a codesequence that represents a position: a digit separator character, a “0” character, a “1” character, and a position segment separator character. For constant speed motion, time duration can be used as a substitute for a digit separator. For a pseudorandom sequence binary position code, a position segment separator character may not be needed because the sequence change from each additional digit can represent a new position. In short, for absolution position encoding as performed with existing methods, at least three code characters are needed.

[0070] FIGS. 3 A-3B, 4, and 5 illustrate example implementations of a new approach for intravascular imaging that eliminates the need for bulky motorized pullback systems that are standard with rotational IVUS or OCT catheters. Using guidewire encoding and sensing, unprecedented distance measurement accuracy is possible with plug and play simplicity, enabling the combination of high-resolution imaging with the simplicity and speed of manual pullback that operators prefer. Catheter ID is an optional feature. Connection to IVUS sensor and to position sensor can be via a single connector, as illustrated, but need not be.

[0071] FIG. 6 illustrates an example system diagram, which is a modified version of a system illustrated in FIG. 29 of WO 2022 / 126101 A2. The Reference Integration System 3105 can include several subsystems, as illustrated in FIG. 6: (1) Communication and Storage subsystem 31230; (2) Data Processing and Position Correlation subsystem 31240; and (3) User Interface and Display 31250. In addition, the modified system of FIG. 6 includes an Imaging System 3106 that is configured to process Imaging Data 3120 and Device Position Data 31220.

[0072] The Communication and Storage subsystem 31230 can interface with external data streams 3110, 3145, 3115, 3125, 3121, store raw data on system memory banks, and provide an internal data stream 31235, allowing the Data Processing and Position Correlation subsystem 31240 to access different streams of data, save the processed data in the system memory bank, and interface with external storage as needed.

[0073] The Device Position Data interface 3110 can interface with a guidewire, therapeutic device and / or diagnostic device to obtain position information input 31220 and store corresponding data in the system memory bank for processing by a Data Processing and Position Correlation subsystem 31240.

[0074] The Computer Network System interface 3145 can transmit and / or receive data from local and / or external network storage systems containing information for signal processing in subsystems 31240 and 31250. The data can be real-time or about real-time andcan be acquired from different procedures and / or steps such as but not limited to ECG (Electrocardiogram), Doppler, FFR (Fractional flow reserve), FFR-CT (Fractional flow reserve-computed tomography), IVUS (intravascular ultrasound), and OCT (Optical coherence tomography). The Computer Network System interface 3145 can provide for saving raw data and final processed data from memory banks to local and / or external storage systems for further data processing from other therapeutic and / or diagnostic systems.

[0075] The Angiogram Data Storage interface 3115 can interface with the Angiogram Data Storage 3108 to obtain real time and / or about real time Angiogram data and store the data in the system memory banks processing by the Data Processing and Position Correlation subsystem 31240.

[0076] The Diagnostic and / or Therapeutic System Data interface 3125 can access diagnostic and therapeutic information before, during, and after procedures from a Diagnostic and / or Therapeutic system 3130, such as but not limited to ECG (Electrocardiogram), Doppler, FFR (Fractional flow reserve), FFR-CT (Fractional flow reserve-computed tomography), IVUS (intravascular ultrasound), and OCT (Optical coherence tomography). The Diagnostic and / or Therapeutic System Data interface 3125 can also access the therapeutic and / or diagnostic device Position Data or portion thereof that is unique to the configuration of the diagnostic and therapeutic systems and devices, such as but not limited to catheter pullback distance (z.e., as obtained at the proximal end of the catheter via an apparatus as part of the diagnostic / therapeutic system).

[0077] The Data Processing / Position Correlation subsystem 31240 can serve several functions. From the angiographic information 3115, including images of the radiopaque markers, the subsystem can establish 2D and / or 3D models of the flexible elongate instrument inside the lumen with dimension information and relative position to the lumen. The subsystem 31240 can receive position and / or displacement information pertaining to the therapeutic and / or diagnostic device in real-time or about real-time from any of: the Device Position Data 31220, the Diagnostic and / or Therapeutic System Data 3130, and the Communication & Storage 31230 via the interface 31235. The subsystem 31240 can integrate the position data with 2D and / or 3D models of the flexible elongate instrument and generating real-time or about real-time device position illustrations, including superimposition of the illustration with the 2D and / or 3D models. The subsystem 31240 can also generate position correlation display data via real-time or about real-time data integration among the 2D / 3D model, simulated device illustration(s), diagnostic and therapeutic systemdata, and Angiogram data. The subsystem 31240 can also provide for input and processing of operator / physician-selected viewing options, such as 2D / 3D, a projection of interest, viewing angles with device signals at any location, and / or other execution requests via the User Interface and Display subsystem 31250.

[0078] The internal data interface 31235 can serve as an interface between the Communication and Storage subsystem 31230 and the Data Processing / Position Correlation subsystem 31240. Raw data, which can include data from the Device Position Data interface 3110, Computer Network System interface 3145, Angiogram Data Storage interface 3115, Diagnostic and / or Therapeutic System Data interface 3125, and Imaging Date interface 3121, can reside in local memory bank within the subsystem 31230.

[0079] The Data Processing / Position Correlation subsystem 31240 can access raw data through the interface 31235. Processed data from the subsystem 31240 can be stored in the memory banks in subsystem 31230 through interface 31235.

[0080] The User Interface and Display subsystem 31250 can place the processed data 31245 from the Data Processing / Position Correlation subsystem 31240 in a proper format 3150 for display by the Display system 3107, such as in a graphical representation based upon User Interface data inputs 31211 from User Interface devices 31210. Operator / physician interface inputs can be embedded into the display data 3150 to display system 3107 or can be embedded into the operator / physician interface data 31211 to the User Interface 31210 as a separated display and control.

[0081] The provided systems and methods can be applied to any interventional procedure for a body lumen. Optionally, a GUI can be rendered on the Reference Integration System 3105 with components or controls to allow an operator to interact with the Reference Integration System 3105 via command control for execution, including providing for interfacing a lumen position correlation display with third-party diagnostic and therapeutic systems. A form of the visualization display system (e.g., display 3107) can vary and can be or include, for example, a monitor, mobile device, wearable device, and AR / VR head mounted device. The inputs from an operator / physician at an operator / physician interface 31210 can be executed via an electronic device, such as a computer, a server with a monitor, a host workstation, a controller with a monitor, and a third-party system operator / physician interface. An I / O can include a keyboardjoystick, mouse, touch display, project device, microphone, any consumer and / or wearable electronics, such as mobile phone, AR headwear, pointing device, and audio feedback, for communicating with the Reference IntegrationSystem 3105 for procedure control, data rendering and visual display, data storage, and basic data process functions. Such a connection mechanism can provide ease of use workflow with adequate customization flexibility on real-time or about real-time lumen position correlation and associated data processing steps for users throughout a guided procedure. The interface connections 3110, 3145, 3125, 31211, 3150, 3115, and 3121 with the Reference Integration System 3105 as shown in FIG. 6 can be established via various connection mechanisms such as cables, cell networks (4G, 5G), local and or wide area network (LAN and WAN), Bluetooth network or wireless.

[0082] As illustrated in FIG. 7, target position data can be co-registered (correlated) with imaging modalities via the reference integration system. Imaging data and positioning data are obtained from catheter 302 coupled to drive device 304, as described herein, and provided to imaging system 726 and reference integration system 727. System timing 729 can be established and / or communicated between systems 726 and 727. As illustrated, IVUS with pullback imaging data 760 or OCT with pullback imaging data 762 can be processed by imaging system 726 and displayed. Reference integration system 727 can implement positioning data processing, image acquisition, and overlay processing to produce a coregistered image 764, which can include overlayed information from several imaging modalities. For example, in addition to the imaging and / or positioning information from catheter 302, angiogram image data 766 can be acquired and provided to reference integration system 727.

[0083] The system configuration illustrated in FIG. 7 can use position encoding and imaging marker(s) as described in WO 2022 / 126101 A2. Furthermore, the configuration can be stand-alone or integrated with a third-party system.

[0084] As illustrated in FIG. 8, the system can optionally include a localization sensor or marker 800 (e.g., an imaging-visible marker) that can enable registration of a system coordinate frame of reference with a coordinate frame of reference of another modality. For example, localization markers / sensors 802, 804 can be included in the first and second flexible elongate instruments, each of which can be a marker 800 capable of appearing in an imaging modality, or one of which can be a marker 800 and the other of which can be detector capable of detecting the marker 800. Here, an encoded guidewire is disposed within the guidewire lumen of a catheter. In one example, the position (spatial) encoding markers (or a position of the device as detected from the position encoding markers) can be spatially aligned with respect to one or more imaging-visible markers of the system. The spatialalignment can provide for registration (e.g., automatic registration, co-regi strati on) of a coordinate frame of reference of the system with an imaging frame of reference. In another example, the position encoding markers of the system (or a position of the device as detected from the position encoding markers) can be spatially aligned with a localization marker visible or otherwise detectable in another modality, as illustrated in FIG. 7. The alignment can be performed such that at least one of the first and second flexible elongate instruments is placed in a defined position and / or orientation in a complementary coordinate system, such as a coordinate system used in electromagnetic tracking / localization, ultrasound-based localization, or optical-shape-sensing-based localization. Upon alignment and registration of a portion of the device in both coordinate systems, position and orientation determinations by the system can be used to verify, refine, or augment spatial measurements obtained by the other modality.

[0085] Example techniques for establishing a reference coordinate system based on a plurality of imaging markers, receiving imaging information (e.g., diagnostic scan information) at a plurality of locations of the first or second flexible elongate instrument, and correlating the information with the imaging markers are described in WO 2022 / 126101 A2. Additional examples are described in WO 2023 / 173108 Al.

[0086] FIG. 9 illustrates an example of a pin configuration 900 for a rotational drive connector. Depending upon the wire type, various pins are assigned to establish two-way communications among microcontrollers and carry IVUS image information. In the example illustrated, pins A and B are assigned for CAN bus communication signals CANH and CANL, pins L and C are assigned for IVUS image signal transmission, and pins H, J, K for identification. Additional pins are used for power (G, M) and for control signals, such as reset signal (D), frame synchronization signal (E), and ready signal (F).

[0087] Advantageously, systems, device, and methods according to the present approach allow an operator to move (e.g., manually retract or advance) the imaging catheter within the body lumen while obtaining imaging data from the rotating imaging transducer and obtaining precise displacement (e.g., position) information from the position sensing element. This makes the operation simpler and more intuitive.

[0088] The teachings of all patents, published applications and references cited herein are incorporated by reference in their entirety.

[0089] While example embodiments have been particularly shown and described, it will be understood by those skilled in the art that various changes in form and details may bemade therein without departing from the scope of the embodiments encompassed by the appended claims.

Claims

CLAIMSWhat is claimed is:

1. A system for intravascular imaging, the system comprising: a first flexible elongated instrument comprising an imaging transducer configured for rotation within the first flexible elongated instrument; a sensing element comprising a sensor configured to detect position information encoding of a second flexible elongate instrument disposed in a body lumen, the sensing element fixedly engaged with the first flexible elongated instrument to enable the sensing element to move together with the first flexible elongated element in the body lumen; and a rotational drive device comprising a coupling element, the coupling element configured to couple to the first flexible elongated instrument and enable the rotational drive device to drive the imaging transducer in rotation, the rotational drive device configured to receive imaging signals from the imaging transducer and obtain signals from the sensor when the coupling element is coupled to the first flexible elongated element.

2. The system of claim 1, further including a controller configured to measure relative displacement of the first and second flexible elongate instruments based on the signals obtained from the sensor.

3. The system of claim 2, wherein the controller is further configured to translate the obtained signals to code characters and determine a position of one of the first and second flexible elongated instruments based on the code characters.

4. The system of claim 2, wherein the rotational drive device includes a motor to drive the imaging transducer in rotation, the controller further configured to control the motor.

5. The system of any one of claims 1-4, wherein the coupling element comprises a mechanical interface configured to mechanically link to the imaging transducer.

6. The system of any one of claims 1-5, wherein the coupling element comprises an electronic interface configured to receive identification information from the first flexible elongated element.

7. The system of any one of claims 1-6, wherein the rotational drive device further comprises a system connector for transmitting a signal indicative of the detected position information encoding to a signal processing and display system.

8. The system of claim 7, wherein the system connector further comprises an interface for transmitting identification information of the sensing element to the signal processing and display system.

9. The system of claim 7, wherein the system connector further comprises an interface for bi-directional communication with the signal processing and display system, the interface being a wired interface, a wireless interface, or a combination thereof.

10. The system of any one of claims 1-9, wherein the sensor is an optical reader and wherein the signal from the sensor is an optical signal transmitted through at least one optical fiber.

11. The system of any one of claims 1-10, wherein the first flexible elongated instrument comprises a guide rail to guide movement of the first flexible elongated instrument, the guide rail having two parts, a distal part positioned between the imaging transducer and a distal end of the first flexible elongated instrument, and a proximal part positioned between the imaging transducer and a proximal end of the first flexible elongated instrument.

12. The system of any one of claims 1-11, wherein the second flexible elongated instrument is a guidewire having position encoding markers.

13. The system of claim 12, further comprising a localization sensor or marker for spatial alignment of at least a subset of the position encoding markers to a position defined in both a coordinate frame of reference of the system and a coordinate frame of reference of another modality.

14. The system of claim 13, wherein the localization marker includes at least one imaging marker.

15. The system of claim 14, wherein the at least one imaging marker includes at least one radiopaque marker positioned at the guidewire at a defined distance from the position encoding markers of the guidewire.

16. The system of any one of claims 1-15, wherein the sensor is placed at a defined distance from the imaging transducer.

17. A method of intravascular imaging, the method comprising: receiving imaging signals from an imaging transducer configured for rotation within a first flexible elongated instrument; while moving the first flexible elongated instrument relative to a second flexible elongated instrument disposed in a body lumen, determining relative displacement between the first and second flexible elongated instruments using a sensing element, the sensing element fixedly engaged with the first flexible elongated instrument and including a sensor configured to detect position encoding information of the second flexible elongated instrument.

18. The method of claim 17, further comprising driving rotational motion of the imaging transducer with a rotational drive device.

19. The method of claim 17 or 18, further comprising, with the sensor, reading encoding markers on the second flexible elongated instrument.

20. The method of any one of claims 17 - 19, further comprising guiding movement of the first flexible elongated instrument relative to the second flexible elongated instrument using a guide rail having two parts, a distal part positioned between the imaging transducer and a distal end of the first flexible elongated instrument, and a proximal part positioned between the imaging transducer and a proximal end of the first flexible elongated instrument.

21. The method of any one of claims 17 - 20, further comprising coupling a coupling element of a rotational drive device to the first flexible elongated instrument, the coupling element enabling the rotational drive device to drive the imaging transducerin rotation, the rotational drive device configured to receive imaging signals from the imaging transducer and obtain signals from the sensor when the coupling element is coupled to the first flexible elongated element.

22. The method of claim 21, wherein the coupling element comprises a mechanical interface configured to mechanically link to the imaging transducer.

23. The method of claim 21 or 22, wherein the coupling element comprises an electronic interface configured to receive identification information from the first flexible elongated element.

24. The method of any one of claims 17 - 23, wherein the sensor is positioned at a defined distance from the imaging transducer.

Images