Intravascular imaging based automatic stent length determination and landing zone selection

Abstract

An apparatus includes a processor configured for communication with an intravascular imaging catheter, and a display. The processor controls the intravascular imaging catheter to obtain intravascular images while the catheter is moved through a blood vessel of a patient. The blood vessel includes a lesion. The processor determines a length of the lesion based on the intravascular images, and determines, based on the length of the lesion, a length for a stent to treat the lesion. The length of the stent and the length of the lesion are distinct from one another. The processor outputs, to the display, a screen display for planning the stent. The screen display includes a visual representation of the blood vessel, and a virtual stent overlaid on the visual representation. The virtual stent includes the length of the stent.

Description

2024PF00152INTRAVASCULAR IMAGING BASED AUTOMATIC STENT LENGTH DETERMINATION AND LANDING ZONE SELECTIONTECHNICAL FIELD

[0001] The present disclosure relates generally to intravascular imaging (e.g., intravascular ultrasound (IVUS), optical coherence tomography (OCT), etc.) using an intravascular imaging catheter for determining length and location for placement of an intravascular stent. In particular, the stent planning system selects a commercially available stent length capable of fully covering a lesion.BACKGROUND

[0002] Intravascular imaging (IVI) (such as intravascular ultrasound (IVUS) or optical coherence tomography (OCT) imaging) is widely used in interventional cardiology as a diagnostic tool for assessing a diseased vessel, such as an artery, within the human body to determine the need for treatment, to guide the intervention, and / or to assess its effectiveness. An IVI device including one or more ultrasound transducers is passed into the vessel and guided to the area to be imaged. The transducers emit ultrasonic energy in order to create an image of the vessel of interest. Ultrasonic waves are partially reflected by discontinuities arising from tissue structures (such as the various layers of the vessel wall), red blood cells, and other features of interest. Echoes from the reflected waves are received by the transducer and passed along to an IVI (e.g., IVUS or OCT) imaging system. The imaging system processes the received ultrasound echoes to produce a cross-sectional image of the vessel where the device is placed.

[0003] Peripheral and coronary vascular procedures, such as stenting, often involve IVI. A stent is a dense (e.g., metallic) object that may be placed in a vessel or lumen to hold the vessel or lumen open to a particular diameter, to counteract the effects of an occlusion, plaque, or compression. Pre-treatment decisions, such as whether and where to place a stent, and selecting the length of the stent, may depend on accurate measurements of the vessel lumen area (and / or other anatomical measurements) across a range of locations within the vessel, made during the procedure itself.

[0004] For example, during the procedure, a physician can use IVI to find diseased segments of the vessel. A physician uses this information to decide what length of stent to place in the vessel to cover the lesion, and where within the vessel to place it. The planned location for stent2024PF00152 placement includes two endpoints: a proximal reference frame or landing zone, and a distal reference frame or landing zone, representing the two ends of the stent.

[0005] Currently, physicians using intravascular imaging must make stenting decisions through a largely manual process of image assessment. This process involves taking inventory of their stent options (e.g. size and length), and matching their available stents to the observed length and morphology of any detected lesions. This can be a lengthy process with a variety of considerations that takes a significant portion of time during a procedure. Additionally, suboptimal or incorrect stent selection and placement can pose significant risk to the health and safety of patients. In short, this is a crucial part of percutaneous coronary intervention (PCI) that can often take significant time and poses significant risk.

[0006] Furthermore, the solutions available do not consider that stent lengths only come in certain length increments (such as 38 mm, 34 mm, 30 mm, 26 mm, etc.) Software may identify a 27.1 mm distance spanning a lesion from one healthy end to another, but there is no 27.1 mm stent; the doctor needs to place a stent that is a real stent length available in the catheterization lab. The user must therefore select locations within the vessel for each landing zone, such that the minimum lumen area occurs between the landing zones, such that the distance between the landing zones is equal to the length of an actual stent currently available in the catheterization lab, and such that the vessel area and / or plaque burden at both landing zones is approximately equal. This places a substantial burden on the user, in the midst of an intravascular procedure, when time is of the essence.

[0007] The information included in this Background section of the specification, including any references cited herein and any description or discussion thereof, is included for technical reference purposes only and is not to be regarded as subject matter by which the scope of the disclosure is to be bound.2024PF00152SUMMARY

[0008] Stent planning systems, devices, and methods are provided for intravascular imaging (e.g., intravascular ultrasound or IVUS, optical coherence tomography or OCT, etc.). Based on intravascular measurements of the vessel diameter or area and lumen diameter or area, the stent planning system identifies the proximal and distal endpoints of a lesion (e.g., the locations of healthy vessel tissue surrounding the lesion), determines an available stent length that is capable of fully covering the lesion, and determines the proximal and distal landing zones for the available stent. The stent planning system has particular but not exclusive utility for intravascular imaging of blood vessels with impeded blood flow (blocked by plaque, compressed by other anatomy, etc.) before stenting, to determine the length of stent to be used and the location where the stent will be placed. Stent length may also be referred to as stent size. The “stent planning system” can also be referred to as a “stent placement determination system”. Stent planning and / or stent placement determination can include a processor automatically determining a commercially available stent length and / or a location for a stent along the blood vessel. The present disclosure thus advantageously provides improved stent planning devices, systems, and methods, that address the concerns noted above.

[0009] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter. A more extensive presentation of features, details, utilities, and advantages of the stent planning system, as defined in the claims, is provided in the following written description of various aspects of the disclosure and illustrated in the accompanying drawings.2024PF00152BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Illustrative aspects of the present disclosure will be described with reference to the accompanying drawings, of which:

[0011] Figure 1 is a diagrammatic schematic view of an intraluminal imaging system, according to aspects of the present disclosure.

[0012] Figure 2 is a schematic diagram of a processor circuit, according to aspects of the present disclosure.

[0013] Figure 3A illustrates a blood vessel incorporating a plaque, according to aspects of the present disclosure.

[0014] Figure 3B illustrates a blood vessel incorporating a plaque and with a stent expanded inside it to restore flow, according to aspects of the present disclosure.

[0015] Figure 4A illustrates a blood vessel incorporating a plaque, according to aspects of the present disclosure.

[0016] Figure 4B illustrates a blood vessel incorporating a plaque and with a stent expanded inside it to restore flow, according to aspects of the present disclosure.

[0017] Figure 5 is a lesion length screen display of an example stent planning system, according to aspects of the present disclosure.

[0018] Figure 6A is a schematic, diagrammatic view, in flow diagram form, of an example stent length determination method, according to aspects of the present disclosure.

[0019] Figure 6B is a schematic, diagrammatic view, in flow diagram form, of an example stent length determination method, according to aspects of the present disclosure.

[0020] Figure 7 is a schematic, diagrammatic representation, in flow diagram form, of an example stent length determination method, according to aspects of the present disclosure.

[0021] Figure 8 is a stent planning screen display of an example stent planning system, according to aspects of the present disclosure.

[0022] Figure 9 is a schematic, diagrammatic representation, in flow diagram form, of an example stent length selection method, according to aspects of the present disclosure.

[0023] Figure 10 is a screen display of an example stent planning system, according to aspects of the present disclosure.

[0024] Figure 11 is a is a screen display of an example stent planning system, according to aspects of the present disclosure.2024PF00152

[0025] Figure 12 is a screen display of an example stent planning system, according to aspects of the present disclosure.

[0026] Figure 13 is a schematic, diagrammatic representation, in flow diagram form, of an example stent placement determination method, according to aspects of the present disclosure.

[0027] Figure 14 is a schematic, diagrammatic representation, in flow diagram form, of a proximal and distal landing zone determination step, according to aspects of the present disclosure.

[0028] Figure 15 is a screen display of an example stent planning system, according to aspects of the present disclosure.

[0029] Figure 16 is a screen display of an example stent planning system, according to aspects of the present disclosure.

[0030] Figure 17 is a screen display of an example stent planning system, according to aspects of the present disclosure.

[0031] Figure 18 is a screen display of an example stent planning system, according to aspects of the present disclosure.

[0032] Figure 19 is a screen display of an example stent planning system, according to aspects of the present disclosure.

[0033] Figure 20 is a screen display of an example stent planning system, according to aspects of the present disclosure.2024PF00152DETAILED DESCRIPTION

[0034] During an intravascular intervention procedure, a physician can use IVI to find diseased segments of the vessel. A physician uses this information to decide what length of stent to place in the vessel to cover the lesion, and where within the vessel to place it. The planned location for stent placement has two landing zones, one for each end of the stent (proximal and distal). Landing zones are typically located in healthy tissue, such as tissue with a plaque burden of less than 50%. However, tissue meeting the landing zone criteria, whether manually or automatically identified, may be separated by a non-integer / non-whole number distance that does not match the length of any commercially available stents.

[0035] In accordance with at least one aspect of the present disclosure, a stent planning system is provided which provides automatic stent length and landing zone adjustment that takes into account the actual lengths of available stents. This enables a user to plan landing zones using real stent lengths available in the lab. This can be deployed as part of automated IVI image interpretation software, or it can work independently of automated image interpretation software.

[0036] Aspects of the present disclosure relate to a processor automatically selecting a commercially available length of the stent during stent planning. Aspects of a processor automatically selecting a location for stent length along the vessel during stent planning are described in, e.g., in Figures 13 and 14, below. The processor automatically selecting a commercially available length and the automatically selecting a location for a stent length can be performed together or independent from one another. Stent planning can also include selecting a diameter of a stent. In some aspects, the diameter of a stent can be determined based on a lumen diameter and / or vessel diameter in an extravascular image of the blood vessel (e.g., an x-ray image of the vessel with contrast). In some aspects, the diameter of a stent can be determined based on a lumen diameter and / or vessel diameter in an intravascular image of the blood vessel (e.g., IVUS or OCT image).

[0037] The stent planning system allows the system and / or the user to place and move a virtual stent in an extraluminal / extravascular view of the vessel (e.g., a 2D image, such as an angiographic x-ray image, a 3D model, etc.) and / or a longitudinal view of the vessel (e.g., an inline digital or image longitudinal display (ILD)).2024PF00152

[0038] Some of the many considerations for stent selection and placement include: location of side branches, location of plaque burden, severity of plaque burden, acuity or diffusion of disease, etc. Stent planning software can help a user identify and measure the lesion and vessel for any given IVUS pullback, helping illuminate many of the above considerations for stenting.

[0039] The present disclosure further streamlines this process can function in example scenarios, including:

[0040] Scenario 1 : The software has identified a lesion and intends to represent this with an automatically generated measurement of an appropriate length (i.e. “a lesion segment” or “disease segment”). To help guide the software-generated length of this lesion, the system can choose from a list of most-common stent lengths and / or a list of user-entered stent lengths (e.g. what the given catheterization lab might have available in their inventory), and round the length of the segment to the closest and most appropriate stent length. This simplifies much of the manual process for adjusting segment length and placement.

[0041] Scenario 2: The user has identified a lesion and intends to create a virtual stent to facilitate stent planning. Instead of forcing the user to create / adjust a stent length from scratch, the system can permit the user to choose from a list of most-common stent lengths and / or a list of user-entered stent lengths.

[0042] Thus, once the clinician uses intravascular imaging to collect data about diseased vessel, the stent planning system can assess the data to identify regions of disease in the vessel, and then generates a measurement (e.g., a “lesion segment” or “disease segment”) to represent an identified region of disease. Instead of creating a segment that does not correspond to a real stent length, thereby forcing the user to spend time modifying the segment, the system would create the segment by selecting from: a list of real stent lengths that were previously entered by the user which represent what they have available in their catheterization lab for treatment a list of real stent lengths that were generated by the system which represent the most commonly available stents lengths found in cath labs.

[0043] This tool can be incorporated directly into IVUS software, but could also apply other intravascular imaging, to instantaneous free wave ratio (iFR) or other physiology measurement modality, or even to non-invasive PCI planning tools, such as computer tomography (CT).2024PF00152

[0044] If a user wants to see both landing zones for a certain stent being planned (a virtual stent), the virtual stent can thus represent a real, available stent length. Current IVI software requires the user to manually adjust the proximal and distal landing zones separately.

[0045] Data is collected about the diseased vessel by means that are available today (e.g. IVUS, iFR, OCT, CT). Before or during review of the data, the system automatically chooses, or the user chooses, a stent length that is a real stent length that can potentially be used to cover the lesion.

[0046] The stent planning system can then automatically find the optimal landing zones for that stent, and display the virtual stent in that location so that the user can visualize the relevant data at that location. In one non-limiting example, the user could see what both landing zones look like with IVUS or OCT. In another example, the user can see the landing zones of the virtual stent relative to physiology readings such as iFR “dots” or other physiological measurement dots that represent a measured drop in pressure across the lesion. In still another example, the user can see the locations of the ends of the stent (or a visualization of the entire stent) on external imaging such as angiography or CT.

[0047] Parameters or criteria for optimizing both landing zones (some of which may be used in combination) include but are not limited to:

[0048] (1) Making both landing zones have equal plaque burden. For example, for a 38mm stent, find the two IVUS frames that are 38mm apart, proximal and distal to the lesion, that have equal plaque burden (e.g., within a threshold amount of one another). (2) Making sure both ends of the virtual stent are a sufficient distance from significant disease. For example, it must be at least x mm from the minimum lumen area, x number of mm from a certain plaque burden percentage (e.g., 75%), or x mm from locations in an iFR pullback with multiple dots (representing a significant pressure drop). (3) Maximizing the amount of plaque covered by the stent. (4) Maximizing the average plaque burden percentage covered by the stent. This is different from maximizing the amount of plaque because the vessel may not be uniform in diameter but rather tapered along its length. Two locations can have the same plaque burden but different amounts of plaque. (5) Minimizing the combined (e.g., summed) plaque burden at the landing zones. In some cases, by moving the virtual stent more proximal or more distal, it may be possible to significantly reduce the plaque burden at one of the landing zones with a less significant impact to the other landing zone. For example, a 38 mm virtual stent might be able to2024PF00152 have landing zones with equal plaque burden, 41% at each landing zone, or that same 38 mm virtual stent might be able to be placed in a slightly different location with 42% plaque burden at one landing zone and 30% plaque burden at the other. (6) Prioritizing additional stent length on the end that is closest to severe disease. In some cases, there may be a localized minimum plaque burden on one end. (7) Avoiding landing zones that partially cover side branches of the blood vessel. Depending on the implementation, the system may employ two or more of these criteria simultaneously (e.g., criterion 1 and criterion 7), or may prioritize the criteria such that, for example, if criterion 1 cannot be met, criterion 2 is used instead, etc., or may select the criteria based on a user input.

[0049] The stent planning system is well-suited to be part of any IVI interpretation software where two ends of a segment can be manipulated independently. The stent planning system includes software that ties the two ends of a segment together with a fixed length that matches the length of an available stent in the real world.

[0050] The devices, systems, and methods described herein can include one or more features described in U.S. Provisional App. No. , filed , and titled “Intravascular Imaging-Based Comparison of Stent Length And Location Options” (Atty Dkt. No. 2023PF00151 / 44755.2424PV01) and U.S. Provisional App. No. 63 / 550,709, filed February 7, 2024, and titled “Stent Placement Planning With Intravascular Imaging And Associated Systems, Devices, And Methods”, each of which is hereby incorporated by reference in its entirety as though fully set forth herein.

[0051] The devices, systems, and methods described herein can include one or more features described in U.S. Provisional App. No. 62 / 750,983, filed 26 October 2018, U.S. Provisional App. No. 62 / 751,268, filed 26 October 2018, U.S. Provisional App. No. 62 / 751,289, filed 26 October 2018, U.S. Provisional App. No. 62 / 750,996, filed 26 October 2018, U.S. Provisional App. No. 62 / 751,167, filed 26 October 2018, and U.S. Provisional App. No. 62 / 751,185, filed 26 October 2018, each of which is hereby incorporated by reference in its entirety as though fully set forth herein.

[0052] The devices, systems, and methods described herein can also include one or more features described in U.S. Provisional App. No. 62 / 642,847, filed March 14, 2018, U.S. Provisional App. No. 62 / 712,009, filed July 30, 2018, U.S. Provisional App. No. 62 / 711,927,2024PF00152 filed July 30, 2018, and U.S. Provisional App. No. 62 / 643,366, filed March 15, 2018, each of which is hereby incorporated by reference in its entirety as though fully set forth herein.

[0053] The stent planning system has particular but not exclusive utility for ultrasound imaging of occluded blood vessels before stenting, to determine the length of stent to be used and the location where the stent will be placed.

[0054] The present disclosure aids substantially in the real-time planning of stent placement during an interventional intravascular procedure, by automatically creating or allowing the user to create and move a virtual stent with a length matched to a real-world stent. The system may also automatically determine the proximal and distal landing zones for the virtual stent. Implemented on an IVI console in communication with an IVI catheter or IVI guidewire in communication with a processor such as a patient interface module (PIM), the stent planning system disclosed herein provides practical improvements in the treatment of vascular diseases. This improved stent placement planning technique transforms a largely manual process that is dependent on expertise, dexterity, and time into one that can be performed repeatably at high speed, without the normally routine need for extensive training of clinicians. This unconventional approach improves the functioning of the ultrasound imaging system, by streamlining the process by which stent lengths and landing zones are determined.

[0055] The stent planning system may be implemented as a process at least partially viewable on a display, and operated by a control process executing on a processor that accepts user inputs from a keyboard, mouse, touchscreen interface, or other user interface, and that is in communication with an intraluminal (e.g., intravascular) imaging device. In that regard, the control process performs certain specific operations in response to different inputs or selections made at different times. Certain outputs of the stent planning system may be printed, shown on a display, or otherwise communicated to human operators. Certain structures, functions, and operations of the processor, display, sensors, and user input systems are known in the art, while others are recited herein to enable novel features or aspects of the present disclosure with particularity.

[0056] These descriptions are provided for exemplary purposes only, and should not be considered to limit the scope of the stent planning system. Certain features may be added, removed, or modified without departing from the spirit of the claimed subject matter.2024PF00152

[0057] For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be made to the aspects illustrated in the drawings, and specific language will be used to describe the same. It is nevertheless understood that no limitation to the scope of the disclosure is intended. Any alterations and further modifications to the described devices, systems, and methods, and any further application of the principles of the present disclosure are fully contemplated and included within the present disclosure as would normally occur to one skilled in the art to which the disclosure relates. In particular, it is fully contemplated that the features, components, and / or steps described with respect to one aspect may be combined with the features, components, and / or steps described with respect to other aspects of the present disclosure. For the sake of brevity, however, the numerous iterations of these combinations will not be described separately.

[0058] Figure 1 is a diagrammatic schematic view of an intraluminal imaging system, according to aspects of the present disclosure. The intraluminal imaging system 100 can be an intravascular ultrasound (IVUS) imaging system in some aspects. The intraluminal imaging system 100 may include an intraluminal device 102, a patient interface module (PIM) 104, a console or processing system 106, a monitor 108, and an external imaging system 132 which may include angiography, ultrasound, X-ray, computed tomography (CT), magnetic resonance imaging (MRI), or other imaging technologies, equipment, and methods. The intraluminal device 102 is sized and shaped, and / or otherwise structurally arranged to be positioned within a body lumen of a patient. For example, the intraluminal device 102 can be a catheter, guide wire, guide catheter, pressure wire, and / or flow wire in various aspects. In some circumstances, the system 100 may include additional elements and / or may be implemented without one or more of the elements illustrated in Figure 1. For example, the system 100 may omit the external imaging system 132.

[0059] The intraluminal imaging system 100 (or intravascular imaging system) can be any type of imaging system suitable for use in the lumens or vasculature of a patient. In some aspects, the intraluminal imaging system 100 is an intravascular ultrasound (IVUS) imaging system. In other aspects, the intraluminal imaging system 100 may include systems configured for forward looking intravascular ultrasound (FL-IVUS) imaging, intravascular photoacoustic (IVPA) imaging, intracardiac echocardiography (ICE), transesophageal echocardiography (TEE), and / or other suitable imaging modalities.2024PF00152

[0060] It is understood that the system 100 and / or device 102 can be configured to obtain any suitable intraluminal imaging data. In some aspects, the device 102 may include an imaging component of any suitable imaging modality, such as optical imaging, optical coherence tomography (OCT), etc. In some aspects, the device 102 may include any suitable imaging or non-imaging component, including a pressure sensor, a flow sensor, a temperature sensor, an optical fiber, a reflector, a mirror, a prism, an ablation element, a radio frequency (RF) electrode, a conductor, or combinations thereof. Generally, the device 102 can include an imaging element to obtain intraluminal imaging data associated with the lumen 120. The device 102 may be sized and shaped (and / or configured) for insertion into a vessel or lumen 120 of the patient.

[0061] The system 100 may be deployed in a catheterization laboratory having a control room. The processing system 106 may be located in the control room. Optionally, the processing system 106 may be located elsewhere, such as in the catheterization laboratory itself. The catheterization laboratory may include a sterile field while its associated control room may or may not be sterile depending on the procedure to be performed and / or on the health care facility. The catheterization laboratory and control room may be used to perform any number of medical imaging procedures such as angiography, fluoroscopy, CT, IVUS, virtual histology (VH), forward looking IVUS (FL-IVUS), intraluminal photoacoustic (IVPA) imaging, a fractional flow reserve (FFR) determination, a coronary flow reserve (CFR) determination, optical coherence tomography (OCT), computed tomography, intracardiac echocardiography (ICE), forward-looking ICE (FLICE), intraluminal palpography, transesophageal ultrasound, fluoroscopy, and other medical imaging modalities, or combinations thereof. In some aspects, device 102 may be controlled from a remote location such as the control room, such than an operator is not required to be in close proximity to the patient.

[0062] The intraluminal device 102, PIM 104, monitor 108, and external imaging system 132 may be communicatively coupled directly or indirectly to the processing system 106. These elements may be communicatively coupled to the medical processing system 106 via a wired connection such as a standard copper link or a fiber optic link and / or via wireless connections using IEEE 802.11 Wi-Fi standards, Ultra Wide-Band (UWB) standards, wireless FireWire, wireless USB, or another high-speed wireless networking standard. The processing system 106 may be communicatively coupled to one or more data networks, e.g., a TCP / IP-based local area network (LAN). In other aspects, different protocols may be utilized such as Synchronous2024PF00152Optical Networking (SONET). In some cases, the processing system 106 may be communicatively coupled to a wide area network (WAN). The processing system 106 may utilize network connectivity to access various resources. For example, the processing system 106 may communicate with a Digital Imaging and Communications in Medicine (DICOM) system, a Picture Archiving and Communication System (PACS), and / or a Hospital Information System (HIS) via a network connection.

[0063] At a high level, an ultrasound imaging intraluminal device 102 emits ultrasonic energy from a transducer array 124 included in scanner assembly 110 mounted near a distal end of the intraluminal device 102. The ultrasonic energy is reflected by tissue structures in the medium (such as a lumen 120) surrounding the scanner assembly 110, and the ultrasound echo signals are received by the transducer array 124. The scanner assembly 110 generates electrical signal(s) representative of the ultrasound echoes. The scanner assembly 110 can include one or more single ultrasound transducers and / or a transducer array 124 in any suitable configuration, such as a planar array, a curved array, a circumferential array, an annular array, etc. For example, the scanner assembly 110 can be a one-dimensional array or a two-dimensional array in some instances. In some instances, the scanner assembly 110 can be a rotational ultrasound device. The active area of the scanner assembly 110 can include one or more transducer materials and / or one or more segments of ultrasound elements (e.g., one or more rows, one or more columns, and / or one or more orientations) that can be uniformly or independently controlled and activated. The active area of the scanner assembly 110 can be patterned or structured in various basic or complex geometries. The scanner assembly 110 can be disposed in a side-looking orientation (e.g., ultrasonic energy emitted perpendicular and / or orthogonal to the longitudinal axis of the intraluminal device 102) and / or a forward-looking looking orientation (e.g., ultrasonic energy emitted parallel to and / or along the longitudinal axis). In some instances, the scanner assembly 110 is structurally arranged to emit and / or receive ultrasonic energy at an oblique angle relative to the longitudinal axis, in a proximal or distal direction. In some aspects, ultrasonic energy emission can be electronically steered by selective triggering of one or more transducer elements of the scanner assembly 110.

[0064] The ultrasound transducer(s) of the scanner assembly 110 can be a piezoelectric micromachined ultrasound transducer (PMUT), capacitive micromachined ultrasonic transducer (CMUT), single crystal, lead zirconate titanate (PZT), PZT composite, other suitable transducer2024PF00152 type, and / or combinations thereof. In an aspect the ultrasound transducer array 124 can include any suitable number of individual transducer elements or acoustic elements between 1 acoustic element and 1000 acoustic elements, including values such as 2 acoustic elements, 4 acoustic elements, 36 acoustic elements, 64 acoustic elements, 128 acoustic elements, 500 acoustic elements, 812 acoustic elements, and / or other values both larger and smaller.

[0065] The PIM 104 transfers the received echo signals to the processing system 106 where the ultrasound image (including the flow information) is reconstructed and displayed on the monitor 108. The console or processing system 106 can include a processor and a memory. The processing system 106 may be operable to facilitate the features of the intraluminal imaging system 100 described herein. For example, the processor can execute computer readable instructions stored on the non-transitory tangible computer readable medium.

[0066] The PIM 104 facilitates communication of signals between the processing system 106 and the scanner assembly 110 included in the intraluminal device 102. This communication may include providing commands to integrated circuit controller chip(s) within the intraluminal device 102, selecting particular element(s) on the transducer array 124 to be used for transmit and receive, providing the transmit trigger signals to the integrated circuit controller chip(s) to activate the transmitter circuitry to generate an electrical pulse to excite the selected transducer array element(s), and / or accepting amplified echo signals received from the selected transducer array element(s) via amplifiers included on the integrated circuit controller chip(s). In some aspects, the PIM 104 performs preliminary processing of the echo data prior to relaying the data to the processing system 106. In examples of such aspects, the PIM 104 performs amplification, filtering, and / or aggregating of the data. In an aspect, the PIM 104 also supplies high- and low- voltage DC power to support operation of the intraluminal device 102 including circuitry within the scanner assembly 110.

[0067] The processing system 106 receives echo data from the scanner assembly 110 by way of the PIM 104 and processes the data to reconstruct an image of the tissue structures in the medium surrounding the scanner assembly 110. Generally, the device 102 can be utilized within any suitable anatomy and / or body lumen of the patient. The processing system 106 outputs image data such that an image of the vessel or lumen 120, such as a cross-sectional IVUS image of the lumen 120, is displayed on the monitor 108. Lumen 120 may represent fluid filled or fluid-surrounded structures, both natural and man-made. Lumen 120 may be within a body of a2024PF00152 patient. Lumen 120 may be a blood vessel, such as an artery or a vein of a patient’s vascular system, including cardiac vasculature, peripheral vasculature, neural vasculature, renal vasculature, and / or or any other suitable lumen inside the body. For example, the device 102 may be used to examine any number of anatomical locations and tissue types, including without limitation, organs including the liver, heart, kidneys, gall bladder, pancreas, lungs; ducts; intestines; nervous system structures including the brain, dural sac, spinal cord and peripheral nerves; the urinary tract; as well as valves within the blood, chambers or other parts of the heart, and / or other systems of the body. In addition to natural structures, the device 102 may be used to examine man-made structures such as, but without limitation, heart valves, stents, shunts, filters and other devices.

[0068] The controller or processing system 106 may include a processing circuit having one or more processors in communication with memory and / or other suitable tangible computer readable storage media. The controller or processing system 106 may be configured to carry out one or more aspects of the present disclosure. In some aspects, the processing system 106 and the monitor 108 are separate components. In other aspects, the processing system 106 and the monitor 108 are integrated in a single component. For example, the system 100 can include a touch screen device, including a housing having a touch screen display and a processor. The system 100 can include any suitable input device, such as a touch sensitive pad or touch screen display, keyboard / mouse, joystick, button, etc., for a user to select options shown on the monitor 108. The processing system 106, the monitor 108, the input device, and / or combinations thereof can be referenced as a controller of the system 100. The controller can be in communication with the device 102, the PIM 104, the processing system 106, the monitor 108, the input device, and / or other components of the system 100.

[0069] In some aspects, the intraluminal device 102 includes some features similar to traditional solid-state IVUS catheters, such those disclosed in U.S. Patent No. 7,846,101, hereby incorporated by reference in its entirety. For example, the intraluminal device 102 may include the scanner assembly 110 near a distal end of the intraluminal device 102 and a transmission line bundle 112 extending along the longitudinal body of the intraluminal device 102. The cable or transmission line bundle 112 can include a plurality of conductors, including one, two, three, four, five, six, seven, or more conductors.2024PF00152

[0070] The transmission line bundle 112 terminates in a PIM connector 114 at a proximal end of the intraluminal device 102. The PIM connector 114 electrically couples the transmission line bundle 112 to the PIM 104 and physically couples the intraluminal device 102 to the PIM 104. In an aspect, the intraluminal device 102 further includes a guidewire exit port 116. Accordingly, in some instances the intraluminal device 102 is a rapid-exchange catheter. The guidewire exit port 116 allows a guidewire 118 to be inserted towards the distal end in order to direct the intraluminal device 102 through the lumen 120.

[0071] The monitor 108 may be a display device such as a computer monitor or other type of screen. The monitor 108 may be used to display selectable prompts, instructions, and visualizations of imaging data to a user. In some aspects, the monitor 108 may be used to provide a procedure-specific workflow to a user to complete an intraluminal imaging procedure. This workflow may include performing a pre-stent plan to determine the state of a lumen and potential for a stent, as well as a post-stent inspection to determine the status of a stent that has been positioned in a lumen.

[0072] The external imaging system 132 can be configured to obtain x-ray, radiographic, angiographic / venographic (e.g., with contrast), and / or fluoroscopic (e.g., without contrast) images of the body of a patient (including the vessel 120). External imaging system 132 may also be configured to obtain computed tomography images of the body of the patient (including the vessel 120). The external imaging system 132 may include an external ultrasound probe configured to obtain ultrasound images of the body of the patient (including the vessel 120) while positioned outside the body. In some aspects, the system 100 includes other imaging modality systems (e.g., MRI) to obtain images of the body of the patient (including the vessel 120). The processing system 106 can utilize the images of the body of the patient in conjunction with the intraluminal images obtained by the intraluminal device 102.

[0073] Figure 2 is a schematic diagram of a processor circuit 250, according to aspects of the present disclosure. The processor circuit 250 may be implemented in the intraluminal imaging system 100, or other devices or workstations (e.g., third-party workstations, network routers, etc.), or on a cloud processor or other remote processing unit, as necessary to implement the method. As shown, the processor circuit 250 may include a processor 260, a memory 264, and a communication module 268. These elements may be in direct or indirect communication with each other, for example via one or more buses.2024PF00152

[0074] The processor 260 may include a central processing unit (CPU), a digital signal processor (DSP), an ASIC, a controller, or any combination of general-purpose computing devices, reduced instruction set computing (RISC) devices, application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or other related logic devices, including mechanical and quantum computers. The processor 260 may also comprise another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein. The processor 260 may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0075] The memory 264 may include a cache memory (e.g., a cache memory of the processor 260), random access memory (RAM), magnetoresistive RAM (MRAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM), flash memory, solid state memory device, hard disk drives, other forms of volatile and non-volatile memory, or a combination of different types of memory. In an aspect, the memory 264 includes a non-transitory computer-readable medium. The memory 264 may store instructions 266. The instructions 266 may include instructions that, when executed by the processor 260, cause the processor 260 to perform the operations described herein. Instructions 266 may also be referred to as code. The terms “instructions” and “code” should be interpreted broadly to include any type of computer-readable statement(s). For example, the terms “instructions” and “code” may refer to one or more programs, routines, sub-routines, functions, procedures, etc. “Instructions” and “code” may include a single computer-readable statement or many computer-readable statements.

[0076] The communication module 268 can include any electronic circuitry and / or logic circuitry to facilitate direct or indirect communication of data between the processor circuit 250, and other processors or devices. In that regard, the communication module 268 can be an input / output (I / O) device. In some instances, the communication module 268 facilitates direct or indirect communication between various elements of the processor circuit 250 and / or the intraluminal imaging system 100. The communication module 268 may communicate within the processor circuit 250 through numerous methods or protocols. Serial communication protocols2024PF00152 may include but are not limited to United States Serial Protocol Interface (US SPI), Inter- Integrated Circuit (I2C), Recommended Standard 232 (RS-232), RS-485, Controller Area Network (CAN), Ethernet, Aeronautical Radio, Incorporated 429 (ARINC 429), MODBUS, Military Standard 1553 (MIL-STD-1553), or any other suitable method or protocol. Parallel protocols include but are not limited to Industry Standard Architecture (ISA), Advanced Technology Attachment (ATA), Small Computer System Interface (SCSI), Peripheral Component Interconnect (PCI), Institute of Electrical and Electronics Engineers 488 (IEEE-488), IEEE- 1284, and other suitable protocols. Where appropriate, serial and parallel communications may be bridged by a Universal Asynchronous Receiver Transmitter (UART), Universal Synchronous Receiver Transmitter (US ART), or other appropriate subsystem.

[0077] External communication (including but not limited to software updates, firmware updates, preset sharing between the processor and central server, or readings from the annular ultrasound imaging array) may be accomplished using any suitable wireless or wired communication technology, such as a cable interface such as a universal serial bus (USB), micro USB, Lightning, or FireWire interface, Bluetooth, Wi-Fi, ZigBee, Li-Fi, or cellular data connections such as 2G / GSM (global system for mobiles) , 3G / UMTS (universal mobile telecommunications system), 4G, long term evolution (LTE), WiMax, or 5G. For example, a Bluetooth Low Energy (BLE) radio can be used to establish connectivity with a cloud service, for transmission of data, and for receipt of software patches. The controller may be configured to communicate with a remote server, or a local device such as a laptop, tablet, or handheld device, or may include a display capable of showing status variables and other information. Information may also be transferred on physical media such as a USB flash drive or memory stick.

[0078] It will also be understood that one or more of the steps of the methods described above can be performed by one or more components of an ultrasound imaging system, such as the processing system, a multiplexer, a beamformer, a signal processing unit, an image processing unit, or any other suitable component of the system. For example, activating the scan sequences may be carried out by a processor in communication with a multiplexer configured to select or activate one or more elements of an ultrasound transducer array. In some aspects, generating the ultrasound images may include beamforming incoming signals from the ultrasound imaging device and processing the beamformed signals by an image processor. The2024PF00152 processing components of the system can be integrated within the ultrasound imaging device, contained within an external console, or may be a separate component.

[0079] Figure 3A illustrates a blood vessel 300 incorporating a plaque 330, according to aspects of the present disclosure. The plaque 330 occurs within the vessel walls 310 and may restrict the flow of blood 320 by reducing the area of the vessel lumen 315. The lumen 315 is defined by the lumen border, and the vessel well 310 is defined by the lumen border 360 and the vessel border 370.

[0080] In the example shown in Figure 3, the blood vessel includes relatively healthy segments 340 and a diseased segment 350. A distal reference frame or landing zone 344 is located in the healthy region 340 distal of the plaque 330, and has a lumen diameter 316 and a vessel diameter 372. A proximal reference frame or landing zone 346 is located in the healthy region 340 proximal of the plaque 330, and has a lumen diameter 318 and a vessel diameter 376. In between the proximal reference frame 346 and the distal reference frame 344 is a target frame 380, which may for example be the frame at which the minimum lumen area (MLA) occurs. The target frame 380 has a lumen diameter 317 and a vessel diameter 374.

[0081] At any given location along the vessel 300, the lumen has a cross-sectional area associated with the lumen diameter, and the vessel has a cross-sectional area associated with the vessel diameter. Each frame or location also has a plaque burden defined as:(Vessel Area - Lumen Area) / Vessel Area (EQN. 1)

[0082] In some cases, the definition of a diseased segment of a vessel may be any segment of the vessel in which the plaque burden exceeds 50% along the entire length of the segment. Thus, generally speaking, for a diseased vessel, the target frame will have a plaque burden of greater than 50% (and often greater than 70%), whereas the proximal and distal reference frames are selected (e.g., by an automated system) such that they have a plaque burden less than 50%, and may for example be the closest proximal and distal frames to the MLA that meet this criterion.

[0083] In the simplified vessel shown Figure 3, the vessel diameter 372, 374, 376 is the same along the length of the blood vessel. However, it is understood that the vessel diameter can vary along the length of the blood vessel. There can be a different vessel diameter 372 at the distal2024PF00152 reference / landing zone 344, diameter 374 at the target frame 380, and diameter 376 at the proximal reference / landing zone 346.

[0084] Figure 3B illustrates a blood vessel 300 incorporating a plaque 330 and with a stent 440 expanded inside it to restore flow, according to aspects of the present disclosure. The stent 440 displaces and arrests the plaque 330 by pushing the lumen border 360 and vessel border 370 outward, thus reducing the restriction of the blood flow 320. Other treatment options for alleviating a plaque or other occlusion may include but are not limited to thrombectomy, ablation, angioplasty, and pharmaceuticals.

[0085] The stent 440 has a diameter 415. The stent also has a proximal edge 446 that has been placed to coincide with the proximal landing zone 346, and a distal edge 444 that has been placed to coincide with the distal landing zone 344. Along the length of the stent 440, the vessel 300 conforms to the stent such that the lumen diameter is equal to the stent diameter 415 at the proximal landing zone 346, the target frame 380, and the distal reference frame 344, as well as at locations in between these points. Notably, the vessel diameters 472 and 476 at the distal and proximal references, respectively, may be larger than the vessel diameters 372 and 376 of Figure 3, and the vessel diameter 474 at the target frame (or former MLA) may be substantially larger than the vessel diameter 374 of Figure 3. In some cases, the stent may be tapered, such that its diameter 346 at the proximal landing zone 476 may be larger than its diameter 472 at the distal landing zone 344.

[0086] Figure 4A illustrates a blood vessel 300 incorporating a plaque 330, according to aspects of the present disclosure. Visible are the vessel wall 310, vessel lumen 315, blood flow 320, plaque 330, lumen border 360, and target frame or target location 380. In the example shown in Figure 4A, a lesion segment 410, which is the length of vessel where an occlusion value (e.g., plaque burden, percent stenosis, which are different from one another, such as calculated differently) is greater than a threshold value, indicating disease. For example, the lesion segment may include locations along the vessel where the plaque burden is greater than 50% (e.g., an example threshold value). The length of the lesion segment is typically a decimal value, e.g., a non-integer, non-whole number value.

[0087] The lesion segment 410 is defined by a distal end 404 and a proximal end 406, which may for example be locations along the vessel 300 at or between locations with occlusions values less than the threshold value and values greater than threshold value. For example, the2024PF00152 distal end 404 and proximal end 406 of the lesion segment 410 may be locations at or between locations with plaque burden greater than 50% and less than 50% (e.g., locations where plaque burden transitions from 50% to 49%. )

[0088] The distal landing zone 420 represents healthy tissue, and can fall at or distal of the distal end 404 of the lesion segment 410. Similarly, the proximal landing zone 430 represents healthy tissue, and can fall at or proximal of the proximal end 406 of the lesion segment 410. The distal landing zone 420 and proximal landing zone 430 may be locations different or distinct from the lesion segment 410, e.g., healthy locations spaced from the proximal and distal ends of the lesion segment 410, and may each represent a potential location or locations (e.g., a region) where the proximal and distal stent edges can be positioned when a stent is deployed.

[0089] The target frame or target location 380 is a location along the vessel 300 that has the maximum occlusion value, and falls between the distal end 404 and proximal end 406 of the lesion segment 410.

[0090] A virtual stent 400 is movable along the length of the vessel 300, and includes a distal end 414 which falls within the range of distal landing zones 420, and a proximal end 416 which falls within the range of proximal landing zones 430. The virtual stent 400 can be different or distinct from the lesion segment 410, and represents the planned length of the stent (e.g., at least as long as, or longer than, the lesion segment), and the planned location of the stent along the vessel 300. As described herein, the planned length of vessel can be an integer or whole number value, because real stents (e.g., commercially available stents) are typically in integer or whole number lengths (e.g., 5 mm, 6 mm, etc.).

[0091] Figure 4B illustrates a blood vessel 300 incorporating a plaque 330 and with a stent 440 expanded inside it to restore flow, according to aspects of the present disclosure. Visible are the blood flow 320, lumen border 360, and target frame or target location 380. In the example shown in Figure 4B, a stent 440 has been placed such that its distal end 444 is within the range of distal landing zones 420 (e.g., at or distal of the distal end 404 of the lesion segment 410), and its proximal end 446 is within the range of proximal landing zones 430 (e.g., at or proximal of the proximal end 406 of the lesion segment 410).

[0092] The length of the stent 440 can be different or distinct from the length of the lesion segment 410. The length of the stent 440 extends over the entire lesion segment 410 (e.g., expanding the diameter of the lesion segment 410, to increase or restore blood flow 320 through2024PF00152 the length of the vessel 300 with the lesion segment 410). The length of the stent (at least as long as or longer than lesion segment) can be an integer or whole number value, because real stents (e.g., commercially available stents) are typically in integer or whole number lengths. The distal end 444 of the stent 440 can be different from the distal end 404 of the lesion segment 410 (e.g., spaced from the distal end 404 of the lesion segment 410), with a location somewhere within the range of distal landing zones 420. The proximal end 446 of the stent 440 can be different from the proximal end 406 of the lesion segment 410 (e.g., spaced from the proximal end of the lesion segment), with a location somewhere within the range of proximal landing zones 430.

[0093] Figure 5 is a lesion length screen display 500 of an example traditional stent planning system 510, according to aspects of the present disclosure. The screen display 500 may for example be generated by an IVI (e.g., IVUS or OCT) image analysis system configured to detect a diseased segment 520 within a vessel, and to automatically select the distal reference frame 544, target frame 580, and proximal reference frame 546 that define the diseased segment.

[0094] The lesion length screen display 500 includes a co-registered angiographic image 530, a graphical image longitudinal display (ILD) 540, and a tomographic image display area 550.

[0095] The angiographic image 530 shows an X-ray image of the blood vessel 300, annotated with a co-registered view of the diseased segment 520, along with its length 560. The angiographic image 530 may for example be captured by the external imaging system 132 (see Figure 1) after a contrast agent has been injected into the patient’s bloodstream. The angiographic image 530 includes a marker indicating target frame 580.

[0096] The ILD 540 includes a stylized graphical view of the blood vessel 300, including a graphical representation of the lumen diameter or area and the vessel diameter or area of the blood vessel 300 at each location along the blood vessel 300. Locations of the distal reference frame 544, target frame 580, and proximal reference frame 546 are marked on the ILD 540, as is the length 560 of the diseased segment 520.

[0097] The tomographic image display area 550 includes tomographic or cross-sectional IVI (e.g., IVUS or OCT) images 554, 555, and 556 and numerical statistics 574, 575, and 576 of the distal reference frame 544, target frame 580, and proximal reference frame 546, respectively.2024PF00152

[0098] The screen display 500 is configured to show, at a glance, multiple types of information helpful for a clinician in understanding the length, position, and severity of the diseased segment 520 within the blood vessel 300. In the example shown in Figure 5, the length 560 of the diseased segment 520 is 10.9 millimeters, which may not correspond to the length of any available stent.

[0099] Figure 6A is a schematic, diagrammatic view, in flow diagram form, of an example stent length determination method 600, according to aspects of the present disclosure. It is understood that the steps of method 600 may be performed in a different order than shown in Figure 6, additional steps can be provided before, during, and after the steps, and / or some of the steps described can be replaced or eliminated in other aspects. One or more of steps of the method 600 can be carried by one or more devices and / or systems described herein, such as components of the system 100, processing system 106, and / or processor circuit 250.

[0100] The method can include: receiving extravascular image and / or controlling extravascular imaging device to obtain extravascular image; co-registration between intravascular image data and extravascular image (as described for example in U.S. Application No. 11 / 473,974, filed June 23, 2006); generating a longitudinal view of the vessel using intravascular image data (as described for example in U.S. Publication No. 2023 / 0181140, filed December 6, 2022, U.S. Provisional Application No. 63 / 288,553, filed December 11, 2021, U.S. Provisional Application No. 63 / 292,529 filed December 22, 2021, International Publication No. WO 2023 / 104541, filed December 7, 2022, International Publication No. WO 2024 / 120659, filed March 28, 2023, and U.S. Application No. 16 / 663,020, filed October 24, 2019, each of which is hereby incorporated by reference as though fully set forth herein); and generating a visual representation of a suitable and available commercial stent size, including a visual representation of a virtual stent overlaid on the longitudinal view and / or on the extravascular image.

[0101] In step 610, the method 600 includes controlling the intravascular imaging catheter to obtain intravascular images (e.g., radial or tomographic image frames) along the blood vessel while the intravascular imaging catheter is moved (e.g., pulled back) through the blood vessel. Execution then proceeds to step 620.

[0102] In step 620, the method 600 includes automatically identifying the lumen border and / or the vessel border in the radial / tomographic IVI image frames. In that regard, aspects of2024PF00152 the present disclosure can include features described in U.S. Publication No. 2007 / 0201736, U.S. Patent No. 11,272,845, U.S. Patent No. 7,463,759, U.S. Patent No. 9,295,447, U.S. Patent No. 11,744,527, U.S. Publication No. 2020 / 0029932, U.S. Publication No. 2019 / 0282211, each of which is hereby incorporated by reference as though fully set forth herein. Execution then proceeds to step 630.

[0103] In step 630, the method 600 includes determining vessel metrics (e.g., vessel diameter(s) or cross sectional area) and / or lumen metrics (e.g., lumen diameter(s) or cross- sectional area) based on the vessel border and / or lumen border. Execution then proceeds to step 640.

[0104] In step 640, the method 600 includes identifying a diseased segment of the blood vessel (e.g., a segment containing a plaque or other lesion), by identifying a proximal reference frame, target frame, distal reference frame, and non-integer / non-whole number length based on the vessel metrics and / or lumen metrics. Execution then proceeds to step 670. As noted by step 645, the method 600 does not include outputting visual representation(s) of the non-integer / non- whole number length to the display, as such information may not be directly useful to the clinician.

[0105] In step 670, the method 600 includes comparing the non-integer / non-whole number length value of the lesion segment to available stent sizes (e.g., stent lengths). The available stent lengths may come from a list 650 that is maintained by the IVI hardware or software manufacturer, and that lists all known commercially available stent lengths, or from a user- maintained list 660 that includes only those commercially available stent lengths that are actually stored in the catheterization laboratory and are thus available for the current procedure. Execution then proceeds to step 680.

[0106] In step 680, the method 600 includes automatically selecting, based on the comparison, an available commercial stent length that is suitable for the lesion segment (e.g., that is capable of completely covering the lesion segment). In some aspects, the selected length will be the smallest available length that is capable of completely covering the lesion segment. Execution then proceeds to step 690.

[0107] In some aspects, steps 670 and 680 are replaced with the processor rounding the non- integer / non-whole number length value of the lesion segment to an integer / whole number. For example, the integer / whole number can be the next / nearest integer / whole number to the non-2024PF00152 integer / non-whole number length value of the lesion segment or one, two, or more millimeters longer than the next / nearest integer / whole number. This integer / whole number can be determined as the value (e.g., stent length) to be outputted to the user in step 690. For example, if the non-integer / non- whole number length value of the lesion segment is 12.4 mm, then the processor can round up this value to 13 mm, such that 13 mm is outputted as the stent length to the user. In other example, if the non-integer / non-whole number length value of the lesion segment is 12.4 mm, then the processor can round up this value to 14 mm, 15 mm, etc. such that 14 mm, 15 mm, etc. mm is outputted as the stent length to the user. In some aspects, this determination that the integer / whole number is the stent length is performed only by rounding up, without comparison to a database / list of commercially available stent lengths generally and / or commercially stent sizes available at the cath lab. This can be advantageous because it is a relatively easier implementation that does not require configuration and / or maintenance of the database / list of commercially stent sizes (by staff at the cath lab and / or the manufacturer of the intravascular imaging software and / or hardware). Outputting the integer / whole number value as the stent length, even if the value is not a commercially available stent length, can still be preferrable for a user (e.g., physician) who is planning to the stent deployment. This is because providing the user (e.g., physician) with an integer / whole number gets closer to the commercially available stent length (which will be an integer / whole number) than providing the user with a non-integer / non-whole number length value of the lesion segment.

[0108] In step 690, the method 600 includes outputting, to a display, a visual representation of the suitable and available stent length. This representation may for example be overlaid on the screen display of Figure 5, to yield the screen display of Figure 8. The method 600 is now complete.

[0109] It is noted that flow diagrams are provided herein for exemplary purposes; a person of ordinary skill in the art will recognize myriad variations that nonetheless fall within the scope of the present disclosure. For example, the logic of flow diagrams may be shown as sequential. However, similar logic could be parallel, massively parallel, object oriented, real-time, event- driven, cellular automaton, or otherwise, while accomplishing the same or similar functions. In order to perform the methods described herein, a processor may divide each of the steps described herein into a plurality of machine instructions, and may execute these instructions at the rate of several hundred, several thousand, several million, or several billion per second, in a2024PF00152 single processor or across a plurality of processors. Such rapid execution may be necessary in order to execute the method in real time or near-real time as described herein. For example, moving the virtual stent in real time, in response to user inputs and with no perception of lag, may require updating the position of the virtual stent on the screen display at a frequency of at least 10 Hz, 20 Hz, 30 Hz, 40 Hz, 60 Hz, 120 Hz, and / or other values both larger and smaller.

[0110] Figure 6B is a schematic, diagrammatic view, in flow diagram form, of an example stent length determination method 601, according to aspects of the present disclosure. It is understood that the steps of method 601 may be performed in a different order than shown in Figure 6, additional steps can be provided before, during, and after the steps, and / or some of the steps described can be replaced or eliminated in other aspects. One or more of steps of the method 601 can be carried by one or more devices and / or systems described herein, such as components of the system 100, processing system 106, and / or processor circuit 250.

[0111] In step 610, the method 601 includes controlling the intravascular imaging catheter to obtain intravascular images (e.g., radial or tomographic image frames) along the blood vessel while the intravascular imaging catheter is moved (e.g., pulled back) through the blood vessel. Execution then proceeds to step 620.

[0112] In step 620, the method 601 includes automatically identifying the lumen border and / or the vessel border in the radial / tomographic IVI image frames. Execution then proceeds to step 630.

[0113] In step 630, the method 601 includes determining vessel metrics (e.g., vessel diameter(s) or cross sectional area) and / or lumen metrics (e.g., lumen diameter(s) or cross- sectional area) based on the vessel border and / or lumen border. Execution then proceeds to step 640.

[0114] In step 640, the method 601 includes identifying a diseased segment of the blood vessel (e.g., a segment containing a plaque or other lesion), by identifying a proximal reference frame, target frame, distal reference frame, and non-integer / non-whole number length based on the vessel metrics and / or lumen metrics. Execution then proceeds to step 670.

[0115] In step 670, the method 601 includes comparing the non-integer / non-whole number length value of the lesion segment to available stent sizes (e.g., stent lengths). The available stent lengths may come from a list 650 that is maintained by the IVI hardware or software manufacturer, and that lists all known commercially available stent lengths, or from a user-2024PF00152 maintained list 660 that includes only those commercially available stent lengths that are actually stored in the catheterization laboratory and are thus available for the current procedure.Execution then proceeds to step 680, and may (depending on the implementation) also proceed to step 695.

[0116] In step 680, the method 601 includes automatically selecting, based on the comparison, an available commercial stent length that is suitable for the lesion segment (e.g., that is capable of completely covering the lesion segment). In some aspects, the selected length will be the smallest available length that is capable of completely covering the lesion segment. Execution then proceeds to step 690.

[0117] In some aspects, steps 670 and 680 are replaced with the processor rounding the non- integer / non-whole number length value of the lesion segment to an integer / whole number. For example, the integer / whole number can be the next / nearest integer / whole number to the non- integer / non-whole number length value of the lesion segment or one, two, or more millimeters longer than the next / nearest integer / whole number. This integer / whole number can be determined as the value (e.g., stent length) to be outputted to the user in step 690. For example, if the non-integer / non- whole number length value of the lesion segment is 12.4 mm, then the processor can round up this value to 13 mm, such that 13 mm is outputted as the stent length to the user. In other example, if the non-integer / non-whole number length value of the lesion segment is 12.4 mm, then the processor can round up this value to 14 mm, 15 mm, etc. such that 14 mm, 15 mm, etc. mm is outputted as the stent length to the user. In some aspects, this determination that the integer / whole number is the stent length is performed only by rounding up, without comparison to a database / list of commercially available stent lengths generally and / or commercially stent sizes available at the cath lab. This can be advantageous because it is a relatively easier implementation that does not require configuration and / or maintenance of the database / list of commercially stent sizes (by staff at the cath lab and / or the manufacturer of the intravascular imaging software and / or hardware). Outputting the integer / whole number value as the stent length, even if the value is not a commercially available stent length, can still be preferrable for a user (e.g., physician) who is planning to the stent deployment. This is because providing the user (e.g., physician) with an integer / whole number gets closer to the commercially available stent length (which will be an integer / whole number) than providing the user with a non-integer / non-whole number length value of the lesion segment.2024PF00152

[0118] In step 690, the method 601 includes outputting, to a display, a visual representation of the suitable and available stent length. This representation may for example be overlaid on the screen display of Figure 5, to yield the screen display of Figure 8. Execution then proceeds to step 695.

[0119] In step 695, the method 601 includes receiving a user input to see the non-integer value length of lesion segment. Execution then proceeds to step 697.

[0120] In step 697, the method 601 includes outputting, to the display, a visual representation or representations of the non-integer value length of lesion segment, to display only in response to the user input. The method 601 is now complete.

[0121] Figure 7 is a schematic, diagrammatic representation, in flow diagram form, of an example stent length determination method 700, according to aspects of the present disclosure. In step 720 the method 700 includes comparing the non-integer / non-whole number lesion segment length (e.g., 10.9 mm) against the list 650 of commercially available stent lengths and / or the list 660 of locally available stent lengths (e.g., a subset of list 650), to select a suitable and available stent length 730 (e.g., 15 mm). The values of the commercially available stent lengths in lists 650 and 660 are exemplary. Other values of commercially available stent length (e.g., other integer / whole number values) smaller, larger, and / or in between are contemplated. In many cases the suitable and available commercial stent length 730 will be the smallest available stent that is capable of completely covering the lesion. For example, the non- integer / non-whole number lesion segment length (e.g., 10.9 mm) can be rounded up to value of the next commercially available stent length (e.g., 15 mm). In these aspects, there can be integer / whole number values between the lesion length and the stent length (e.g., 11 mm, 12 mm, 13 mm, and 14 mm are between 10.9 mm and 15 mm).

[0122] Figure 8 is a stent planning screen display 800 of an example stent planning system 810, according to aspects of the present disclosure. In the example shown in Figure 8, the proximal target frame or landing zone 546 has been automatically moved to the right as compared with the proximal target frame or landing zone 546 of Figure 5, in order to change the length 560 of the segment to an integer / whole number (e.g., 15 mm) that corresponds with the length of an available stent. In other aspects, in order to round the stent length up to the next available length, the distal landing zone 544 is moved to be more distal, and the proximal landing zone 546 is not moved. In still other aspects, both the proximal and distal landing zones may be2024PF00152 moved outward (e.g., such that they are centered around the target frame 580, or based on other criteria).

[0123] This automatic selection of stent length and position may, in some cases, be overridden by the user. This may be done for example by typing a new length value into the text box 805, or by grabbing the proximal handle 820 of the ILD or co-registered angiographic image and dragging it in a proximal direction. Similarly, dragging the proximal handle 820 in a distal direction can shorten the segment. There is also a distal handle 630 in both the ILD and the angiographic image that can be used to lengthen or shorten the segment by moving the distal reference frame or landing zone 544 in a proximal or distal direction. The angiographic image 530 includes a marker indicating target frame 580. The proximal image 556 and the corresponding statistics 576 change from Fig. 5 to Fig. 8 because of the change from the length of lesion / diseased segment 520 in Fig. 5 to the length of the virtual stent 560 in Fig. 8.Once the length of the segment 520 has been adjusted to match the length of an available stent, the segment 520 may be considered a virtual stent 860. It is noted that in the example shown in Figure 8, the 15 mm virtual stent is in a good placement, as the distal landing zone plaque burden 840 is similar to the proximal landing zone plaque burden 850, and because the proximal landing zone plaque burden 850 is less than 50%. Thus, a user may not want to move the virtual stent 860 to a different location.

[0124] The shape of the markers indicating the target frame 580 and / or proximal and distal handles 820, 830 in the ILD or the angiographic image are exemplary. The shapes can be lines, rectangles, circles, dotted, solid, etc., and / or combinations thereof. The shapes can be positioned over and / or across the vessel (e.g., transversely). The shapes of the markers indicating the target frame 580 and / or proximal and distal handles 820, 830 can be the same as one another or different from one another. In some aspects, for information purposes, hovering a pointer over the text box 805 will show the non-integer / non-whole number length of the disease segment.

[0125] Figure 9 is a schematic, diagrammatic representation, in flow diagram form, of an example stent length selection method 900, according to aspects of the present disclosure.

[0126] In step 910, the method 900 includes receiving a user input to add a virtual stent to the current screen display. Execution then proceeds to step 920.

[0127] In step 920, the method 900 includes retrieving a list of commercial stent lengths. Depending on the implementation and / or on one or more user inputs, this may be the2024PF00152 manufacturer-maintained list 650 of commercially available stent lengths, or the user-maintained list 660 of locally available stent lengths. Execution then proceeds to step 930.

[0128] In step 930, the method 900 includes outputting the list of commercial stent lengths to the display. This may for example take the form of a pull-down menu or other menu. Execution then proceeds to step 940.

[0129] In step 940, the method 900 includes receiving a user input selecting one of the available commercial stent lengths from the list. Execution then proceeds to step 950.

[0130] In some aspects, steps 920-940 are replaced with the processor receiving a user input identifying an integer / whole number value (e.g., stent length). For example, the integer / whole number value can be identified without reference to a database / list of commercially available stent lengths generally and / or commercially stent sizes available at the cath lab. This can be advantageous because it is a relatively easier implementation that does not require configuration and / or maintenance of the database / list of commercially stent sizes (by staff at the cath lab and / or the manufacturer of the intravascular imaging software and / or hardware). In some aspects, the user input of the stent length can be received in response to the processor outputting a list of integer / whole number values (e.g., similar to Figures 10 and 11, but with more or all integer / whole number values, instead of only commercially available stent length). The user input can be a selection from the list. In some aspects, the user input of the stent length can be received via the user manually entering the integer / whole number value (e.g., as similarly shown in Figure 17) via keyboard, number pad, mouse, touchscreen display, and / or other suitable user input device. In some aspects, the user input of the stent length can be received via length add / increase and / or length subtract / decrease keys (similar to plus button 1830 and / or minus button 1850 in Figures 18 and 20). The integer / whole number value may or may not be a commercially available stent length. Outputting the integer / whole number value as the stent length, even if the value is not a commercially available stent length, can still be preferrable for a user (e.g., physician) who is planning to the stent deployment. This is because providing the user (e.g., physician) with an integer / whole number gets closer to the commercially available stent length (which will be an integer / whole number) than providing the user with a non-integer / non- whole number length value of the lesion segment.

[0131] In step 950, the method 900 includes positioning a virtual stent around the target frame. This placement may for example be symmetric, such that the proximal and distal landing2024PF00152 zones are equidistant from the target frame, or may be based on other criteria as described below. Execution then proceeds to step 960.

[0132] In step 960, the method 900 includes outputting, to a display, a visual representation of the virtual stent having the user-selected available stent length. The method 900 is now complete.

[0133] Figure 10 is a screen display 1000 of an example stent planning system 810, according to aspects of the present disclosure. In the example shown in Figure 10, the user has dragged a scrubber 1005 to a manually selected target frame located inside the diseased vessel segment 520. As the scrubber moves proximally or distally, the frame number 1010 and tomographic image 1020 change to represent different frames in the IVI pullback sequence, and the target frame indicator 580 also moves within the angiographic image. This can be useful for example so that a clinician can examine the entire length of a diseased segment to obtain a better understanding of the vessel geometry, and may be used to manually set a target frame. Also visible are a pointer 1030, a list 1040 of available stent lengths, and an “add length”, “add segment”, or “add stent” button 1050, which may for example be used to bring up the list 1040.

[0134] Figure 11 is a is a screen display 1000 of an example stent planning system 810, according to aspects of the present disclosure. In the example shown in Figure 11, the pointer 1030 has been moved over the list 1040 of available stent lengths, in order to select a particular stent length 1150. This step bypasses the display of a non-integer / non-whole number length for a diseased vessel segment or virtual stent, and instead allows the user (e.g., a clinician) to directly select only stent lengths that are actually available.

[0135] Figure 12 is a screen display 1200 of an example stent planning system 810, according to aspects of the present disclosure. In the example shown in Figure 12, the user has selected a stent length 560 of 15 mm. The system 810 has responded by, in the screen display 1200, placing the target frame 580 at the location of the scrubber, and selecting a proximal landing zone 546 and distal landing zone 544 that are equidistant from the target frame 580 (e.g., each of them located 7.5 mm from the target frame, or half of the length of the virtual stent). Tomographic images 554, 555, and 556 of the distal, target, and proximal frames are shown in the tomographic frame display area 550. The user is now free to reposition the virtual stent to achieve more favorable metrics 574, 574, and 576. For example, it is noted that the proximal landing zone 546 has a plaque burden of 72.8%, which is both (a) higher than 50% (and may2024PF00152 thus not represent healthy tissue), and (b) significantly different than the plaque burden of 45.3% for the distal landing zone 544 (and may thus not provide a symmetric plaque burden, as may be desired by the clinician). Thus, the clinician may wish to reposition the virtual stent, e.g., by using the pointer to grab the handles 820 or 830 (see Figure 8) or the entire virtual stent 860.

[0136] Figure 13 is a schematic, diagrammatic representation, in flow diagram form, of an example stent placement determination method 1300, according to aspects of the present disclosure.

[0137] In step 1310, the method 1300 includes controlling the intravascular imaging catheter to obtain intravascular image data (e.g., radial / tomographic image frames) during movement (e.g., pullback) through the blood vessel. Execution then proceeds to step 1320.

[0138] In step 1320, the method 1300 includes automatically identifying the vessel border and / or the lumen border in the radial / tomographic image frames. Execution then proceeds to step 1330.

[0139] In step 1330, the method 1300 includes determining (e.g., based on the vessel border and / or lumen border), the vessel metric(s) or lumen metric(s). Vessel metrics may for example include vessel diameter(s) and / or vessel cross-sectional area. Lumen metric(s) may for example include the lumen diameter(s) and / or lumen cross-sectional area. Execution then proceeds to step 1340.

[0140] In step 1340, the method 1300 includes determining the distal end and proximal end of the lesion segment of the vessel (e.g., the true, non-integer / non- whole number value length of the lesion segment) based on the vessel metric(s) and / or lumen metric(s). Execution then proceeds to step 1350.

[0141] In step 1350, the method 1300 involves obtaining an available commercial stent length that is suitable for treating the lesion segment. This may be done manually or automatically, as described above.

[0142] In step 1360, the method 1300 involves determining the proximal and distal landing zones for the suitable and commercially available stent. This determination can be made automatically, as described below in Figures 14-15. Execution then proceeds to step 1370.

[0143] In step 1370, the method 1300 includes outputting, to a display, a visual representation of the suitable and commercially available stent length at the determined proximal2024PF00152 and distal landing zones. This may for example be a virtual stent that can be moved by the user if desired, as described above.

[0144] Figure 14 is a schematic, diagrammatic representation, in flow diagram form, of a proximal and distal landing zone determination step 1360, according to aspects of the present disclosure. Inputs to a comparison process include the vessel metrics and / or lumen metrics 1410 (e.g., vessel / lumen diameter(s) or cross-sectional area), as well as the distal and proximal ends 1430 of the diseased segment based on the metrics 1410. In an example, the proximal and distal landing zone determination step 1360 may choose only landing zones that are at or outside of the distal and proximal ends 1430 of the diseased segment.

[0145] Other inputs include the plaque burden 1420 (see Eqn. 1). In an example, the proximal and distal landing zone determination step 1360 may choose only landing zones with a plaque burden of less than 50%,

[0146] Other inputs include a desired landing zone parameter A, 1440, which may for example be to choose proximal and distal landing zones whose plaque burdens are approximately equal to one another (e.g., within a threshold value of one another (e.g., within 2.5% of one another)).

[0147] Other inputs may include a desired landing zone parameter B, 1450, which may for example be to choose proximal and distal landing zones that maximize the average plaque burden covered by the stent. It is noted that parameters 1440 and 1450 may conflict with one another, and may thus be selected in a hierarchical fashion, such as applying parameter B, 1450, unless it conflicts with parameter A, 1440, in which case parameter A is used instead. It is understood that parameter A, 1440 and parameter B, 1450, can be calculated based on any combination of inputs 1410, 1420, and / or 1430.

[0148] Other inputs may include landing zone parameter C, 1460, which may be applied regardless of other parameters. In a non-limiting example, parameter C, 1450, may specify that the selected landing zones cannot partially cover one or more side branches of the vessel.

[0149] Possible landing zone parameters, which may be applied in parallel, in hierarchy, or one at a time, include but are not limited to:1) Making both landing zones have equal plaque burden. For example, for a 38mm stent, find the two IVUS frames that are 38mm apart, proximal and distal to the lesion, that have equal plaque burden.2024PF001522) Making sure both ends of the virtual stent are a sufficient distance from significant disease. For example, it must be at least x mm from the minimum lumen area, x number of mm from a certain plaque burden percentage, or x mm from locations in an iFR pullback with multiple dots (representing significant pressure drop).3) Maximizing the amount of plaque covered by the stent.4) Maximizing the average plaque burden percentage covered by the stent. This is different from maximizing the amount of plaque covered, because the vessel may not be uniform in diameter, but tapered. Two locations can have the same plaque burden but different amounts of plaque.5) Minimizing the combined plaque burden at the landing zones. By moving the virtual stent more proximal or more distal, it might be possible to significantly reduce the plaque burden at one of the landing zones with a less significant impact to the other landing zone. For example, a 38 mm virtual stent might be able to have landing zones with equal plaque burden, 41% at each landing zone. Or that same 38 mm virtual stent might be able to be placed in a slightly different location with 42% plaque burden at one landing zone and 30% plaque burden at the other.6) Prioritizing additional stent length on the end that is closest to severe disease. In some cases, there may be a localized minimum plaque burden on one end. For example, the minimum plaque burden that a certain stent length can reach might be.7) Avoiding landing zones that partially cover side branches.It is understood that still other parameters may be selected, without departing from the spirit of the present disclosure.

[0150] Based on the inputs 1410, 1420, 1430, 1440, 1450, and 1460, or others as described above, step 1470 computes the proximal and distal landing zones for the suitable and available stent length.

[0151] It is noted that in some cases, due to the length and / or location of the diseased vessel segment, the suitable and available stent length selected above cannot meet the specific landing zone parameters. In such a case, the length of the stent may be increased to the next available stent length, and the proximal and distal landing zone determination step 1360 may be repeated.

[0152] Figure 15 is a screen display 1200 of an example stent planning system 810, according to aspects of the present disclosure. In the example shown in Figure 15, the system has automatically selected a stent length 560 of 15 mm, or a user has selected this stent length, stent planning system 810 by, in the screen display 1500, placing the scrubber 1005 at the2024PF00152 location of the automatically computed target frame 580, and selecting a proximal landing zone 546 and distal landing zone 544 based on the inputs and criteria described in Figure 14. Unlike Figure 8, where the proximal and distal plaque burdens are quite different from one another, the proximal and distal plaque burdens in Figure 15 are quite similar. Tomographic images 554, 555, and 556 of the distal, target, and proximal frames are shown in the tomographic frame display area 550. The user is now free to reposition the virtual stent 860, although this may be both unnecessary and inadvisable, given the criteria used for automatic selection of the landing zones 544, 546.

[0153] Figure 16 is a screen display 1600 of an example stent planning system 810, according to aspects of the present disclosure. In the example shown in Figure 16, the coregistered angiographic image 530 has been annotated with dots 1610, wherein each dot 1610 along the length of the vessel represents a change of 0.01 in the value of the instantaneous free wave ratio (iFR) at that location. Reductions in iFR are generally correlated with constrictions in the blood vessel, so a target frame (e.g., the location of maximum constriction) 580 can be selected at the location with the greatest number of iFR dots, and the stent length 560 can be selected based on the number of iFR dots the clinician wishes to correct. In the example shown in Figure 16, the total drop in iFR across the length of the vessel 300 is 0.2 (nondimensional), of which 0.09 occurs within the diseased segment 520. The selected stent length 560 of 15.0 mm is sufficient to cover the diseased segment, and thus to cover (and thus eliminate) 9 iFR dots, thus leaving the vessel with a total iFR reduction of 0.11.

[0154] Pressing an “Add Length”, “Add Segment”, or “Add Stent” button 1620 creates the virtual stent 860. The clinician has the option of moving the virtual stent 860 (e.g., by grabbing and dragging it with a pointer), or of resizing it to the next larger or smaller available stent length, either by dragging one of the handles 820 or 830, or by typing a new value into text box 560, or by pressing a “plus” sign 1630 or “minus” sign 1640. This may be done for example to increase or decrease the number of iFR dots the stent is capable of covering. Also visible are the distal iFR value 1630 of the vessel (e.g., the value measured at the distalmost portion of the pullback), the estimated distal iFR 1640 after treatment with the stent, and a graph 1650 showing the changes in iFR over the length of the pullback.

[0155] In some aspects, iFR dots or other physiological measurement dots may be considered a type of vessel metric or lumen metric. Depending on the implementation, the2024PF00152 clinician may have the option of switching back and forth between the iFR mode of Figure 16 and the plaque burden mode or vessel measurements mode of Figure 8.

[0156] Figure 17 is a screen display 1700 of an example stent planning system 810, according to aspects of the present disclosure. In the example shown in Figure 17, the user has dragged a scrubber 1005 to a manually selected target frame located inside the diseased vessel segment 520. Also visible are a pointer 1730, a keypad 1740 of available stent lengths, and a text entry window 1770. In an example, the user moves and clicks the pointer 1730 on the keypad 1740 to enter numerals that are displayed in the text entry screen 1770, in order to manually enter an available stent length. The keypad 1740 can be a touch screen, a physical number pad (e.g., as part of a keyboard), or a virtual keypad operated by a mouse or trackball.

[0157] Figure 18 is a screen display 1700 of an example stent planning system 810, according to aspects of the present disclosure. In the example shown in Figure 18, the user has dragged a scrubber 1005 to a manually selected target frame located inside the diseased vessel segment 520. Also visible are a pointer 1830, stent length indicator 1840, minus button 1850, and plus button 1860. Pressing the plus button 1860 (e.g., by clicking with the pointer 1830) will increase or add length to the stent length indicated by the stent length indicator 1840, while pressing the minus button 1850 will decrease or subtract length from the stent length indicated by the stent length indicator 1840. Typically, when user presses a plus or minus button, the stent length value is incremented or decremented by a decimal amount (e.g., 0.1 mm) each time the button is pressed. This may not be helpful for stent planning, because stents are generally available in whole number increments (e.g., 10 mm, 15 mm, etc.). As described in 18 and 19, pressing the plus or minus buttons changes the stent length value in a whole number amount, either by bumping it up or down to the next commercially available or locally available length, or to the next whole number.

[0158] Figure 19 is a screen display 1900 of an example stent planning system 810, according to aspects of the present disclosure. In the example shown in Figure 19, the user has clicked the plus button 1860, thus instructing the stent planning system to increase the stent length 1840 to the next available length (e.g., from 10 mm to 15 mm, if that is the next available length on the list of available stent lengths). Similarly, if the user clicks on the minus button 1850, the stent planning system will go to the next smaller available length (e.g., from 10 mm to 8 mm, if that is the next available length on the list of available stent lengths).2024PF00152

[0159] Figure 20 is a screen display 2000 of an example stent planning system 810, according to aspects of the present disclosure. In the example shown in Figure 20, the user has clicked the plus button 1860, thus instructing the stent planning system to increase the stent length 1840 to the next whole number (e.g., from 10 mm to 11 mm, if that is the next larger whole number). Similarly, if the user clicks on the minus button 1850, the stent planning system will go to the next smaller available length (e.g., from 10 mm to 9 mm, if that is the next smaller whole number).

[0160] Accordingly, it can be seen that the stent planning system advantageously permits the users of intraluminal imaging systems to determine the appropriate length and landing zones for a stent, with enhanced speed, accuracy, and repeatability. This technology can be applied to other types of ultrasound devices besides IVUS, including but not limited to 2D or 3D external ultrasound, trans-esophageal echography (TEE), or intracardiac echography (ICE), as well as optoacoustic or photoacoustic imaging technologies such as optical coherence tomography (OCT). The technology can be used in either or both of veins and arteries, including coronary arteries. The stent planning system’s workflow with the GUI interface may be highly visible. This technology could be applied to percutaneous coronary intervention or peripheral endovascular intervention, and may be useful not only for stent planning but for planning and deployment of other therapies used in these types of interventional procedures. For example, any type of angioplasty device, atherectomy device, or drug delivery device of a known length could potentially benefit from this type of IVI planning software.

[0161] A system of one or more computers can be configured to perform particular operations or actions by virtue of having software, firmware, hardware, or a combination of them installed on the system that in operation causes or cause the system to perform the actions. One or more computer programs can be configured to perform particular operations or actions by virtue of including instructions that, when executed by data processing apparatus, cause the apparatus to perform the actions. One general aspect includes an apparatus that includes a processor configured for communication with an intravascular imaging catheter and a display, where the processor is configured to: control the intravascular imaging catheter to obtain a plurality of intravascular images while the intravascular imaging catheter is moved through a blood vessel of a patient, where the blood vessel may include a lesion; determine a length of the lesion based on the plurality of intravascular images; determine, based on the length of the2024PF00152 lesion, a length for a stent to provide treatment for the lesion, where the length of the stent is a whole number such that the length of the stent and the length of the lesion are distinct from one another, output, to the display, a screen display for planning the stent, where the screen display may include: a visual representation of the blood vessel; and a virtual stent overlaid on the visual representation, where the virtual stent may include the length of the stent. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to perform the actions of the methods.

[0162] Implementations may include one or more of the following features. In some aspects, the length of the stent is a whole number value and the length of the lesion is a non-whole number value. In some aspects, the length of the lesion is not provided in the screen display. In some aspects, the length of the stent is displayed before the length of the lesion is displayed. In some aspects, while the length of the stent is displayed, the processor is configured to receive a user input to display the length of the lesion, where the length of the lesion is displayed only after the user input is received. In some aspects, to determine the length of the stent, the processor is configured to retrieve a list of commercially available stent lengths stored in a memory in communication with the processor. In some aspects, to determine the length of the stent, the processor is configured to: compare the length of the lesion to the list of commercially available stent lengths; and select the length of the stent based on the comparison. In some aspects, the processor is further configured to obtain a location for the stent, where the virtual stent is overlaid at the location on the visual representation. In some aspects, the location for the stent, the processor is configured to receive a user input representative of a manually-identified location. In some aspects, to obtain the location for the stent, the processor is configured to automatically determine the location for the stent based on at least one of a plurality of vessel metrics or a plurality of lumen metrics for the plurality of intravascular images. In some aspects, the location may include a proximal landing zone and a distal landing zone, where a criterion is associated with at least one of the proximal landing zone or the distal landing zone, where the criterion may include at least one of: a plaque burden of the proximal landing zone being within a threshold value of a plaque burden of the distal landing zone; or both the proximal landing zone and the distal landing zone being at least a threshold distance from significant disease; or an amount of plaque covered by the stent being maximized; or an average plaque burden percentage covered by the stent being maximized; or a combined plaque burden at the proximal and distal2024PF00152 landing zones being minimized; or prioritizing additional stent length on the landing zone that is closest to severe disease; or neither the proximal landing zone nor the distal landing zone partially covering a side branch of the blood vessel. Implementations of the described techniques may include hardware, a method or process, or computer software on a computer- accessible medium.

[0163] One general aspect includes an apparatus that includes a processor configured for communication with an intravascular imaging catheter and a display, where the processor is configured to: control the intravascular imaging catheter to obtain a plurality of intravascular images while the intravascular imaging catheter is moved through a blood vessel of a patient, where the blood vessel may include a lesion; automatically determine a location for a stent to provide treatment for the lesion, where the location is determined based on satisfying a criterion associated with at least one of a plurality of vessel metrics or a plurality of lumen metrics for the plurality of intravascular images; and output, to the display, a screen display for planning the stent, where the screen display may include: a visual representation of the blood vessel; and a virtual stent overlaid at the location on the visual representation. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to perform the actions of the methods.

[0164] Implementations may include one or more of the following features. In some aspects, the location may include a proximal landing zone and a distal landing zone, where a criterion is associated with at least one of the proximal landing zone or the distal landing zone. In some aspects, the criterion may include at least one of: a plaque burden of the proximal landing zone being within a threshold value of a plaque burden of the distal landing zone; or both the proximal landing zone and the distal landing zone being at least a threshold distance from a plaque burden exceeding the threshold value; or an amount of plaque covered by the stent being maximized; or an average plaque burden percentage covered by the stent being maximized; or a combined plaque burden at the proximal and distal landing zones being minimized; or prioritizing additional stent length on the landing zone that is closest to a location within the lesion that has the greatest plaque burden; or neither the proximal landing zone nor the distal landing zone partially covering a side branch of the blood vessel. In some aspects, the processor is further configured to obtain a length for the stent, and the virtual stent may include the length of the stent. In some aspects, to obtain the length of the stent, the processor is configured to receive a2024PF00152 user input representative of a manually-identified length. In some aspects, to obtain the length of the stent, the processor is further configured to automatically determine, based on the plurality of intravascular images, the length of the stent, where the length of the stent and a length of the lesion are distinct from one another. In some aspects, the length of the stent is a whole number value and the length of the lesion is a non-whole number value.

[0165] One general aspect includes a system that includes a processor circuit configured for communication with an intravascular catheter or guidewire, where the processor circuit is configured to: control the intravascular catheter or guidewire obtain a plurality of intravascular images, intravascular pressure measurements, or intravascular flow measurements while the intravascular catheter or guidewire is moved through a blood vessel of a patient, where the blood vessel may include a lesion; select a stent length from a list of available stent lengths; output a screen display for planning a stent to provide treatment for the lesion, where the screen display may include: a visual representation of the blood vessel; and a virtual stent of the selected length overlaid in a first position on the visual representation. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to perform the actions of the methods.

[0166] Implementations may include one or more of the following features. In some aspects, the list of available stent lengths is a manufacturer-maintained list or a user-maintained list. In some aspects, selecting the stent length from the list of available stent lengths involves receiving a user input. . In some aspects, a vessel metric or a lumen metric of the blood vessel is maximized or minimized; or a user input has selected the target frame, placing a center of the virtual stent at the target frame. In some aspects, selecting the stent length from the list of available stent lengths involves: based on the plurality of intravascular images or physiological measurements, generating vessel metrics or lumen metrics for the blood vessel; based on the vessel metrics or lumen metrics, identifying a proximal landing zone and a distal landing zone of a diseased segment of the blood vessel; identifying a distance between the proximal landing zone and the distal landing zone; and selecting, from the list of available stent lengths, a first stent length that is larger than the distance. In some aspects, the system may include: based on at least one criterion, adjusting the proximal landing zone or the distal landing zone such that the distance between the proximal landing zone and the distal landing zone is equal to the selected stent length. In some aspects, the at least one criterion may include at least one of: a plaque2024PF00152 burden of the proximal landing zone being within a threshold value of a plaque burden of the distal landing zone; or both the proximal landing zone and the distal landing zone being at least a threshold distance from significant disease; or an amount of plaque covered by the stent being maximized; or an average plaque burden percentage covered by the stent being maximized; or a combined plaque burden at the proximal and distal landing zones being minimized; or prioritizing additional stent length on the landing zone that is closest to severe disease; or the stent covering at least a threshold number of physiological measurement dots; or neither the proximal landing zone nor the distal landing zone partially covering a side branch of the blood vessel. In some aspects, the screen display further may include an intravascular image, vessel metric, lumen metric, or physiology measurement corresponding to the proximal landing zone and an intravascular image, vessel metric, lumen metric, or physiology measurement corresponding to the distal landing zone. In some aspects, the screen display further may include a plurality of physiological measurement dots positioned along the visual representation of the blood vessel. Implementations of the described techniques may include hardware, a method or process, or computer software on a computer-accessible medium.

[0167] The logical operations making up the aspects of the technology described herein are referred to variously as operations, steps, objects, elements, components, modules, etc. Furthermore, it should be understood that these may occur or be performed or arranged in any order, unless explicitly claimed otherwise or a specific order is inherently necessitated by the claim language.

[0168] All directional references e.g., upper, lower, inner, outer, upward, downward, left, right, lateral, front, back, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise, proximal, and distal are only used for identification purposes to aid the reader’s understanding of the claimed subject matter, and do not create limitations, particularly as to the position, orientation, or use of the stent planning system. Connection references, e.g., attached, coupled, connected, joined, or “in communication with” are to be construed broadly and may include intermediate members between a collection of elements and relative movement between elements unless otherwise indicated. As such, connection references do not necessarily imply that two elements are directly connected and in fixed relation to each other. The term “or” shall be interpreted to mean “and / or” rather than “exclusive or.” The word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a2024PF00152 plurality. Unless otherwise noted in the claims, stated values shall be interpreted as illustrative only and shall not be taken to be limiting.

[0169] The above specification, examples and data provide a complete description of the structure and use of exemplary aspects of the stent planning system as defined in the claims. Although various aspects of the claimed subject matter have been described above with a certain degree of particularity, or with reference to one or more individual aspects, those skilled in the art could make numerous alterations to the disclosed aspects without departing from the spirit or scope of the claimed subject matter.

[0170] Still other aspects are contemplated. It is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative only of particular aspects and not limiting. Changes in detail or structure may be made without departing from the basic elements of the subject matter as defined in the following claims.

Claims

2024PF00152CLAIMSWhat is claimed is:

1. An apparatus, comprising: a processor configured for communication with an intravascular imaging catheter and a display, wherein the processor is configured to: control the intravascular imaging catheter to obtain a plurality of intravascular images while the intravascular imaging catheter is moved through a blood vessel of a patient, wherein the blood vessel comprises a lesion; determine a length of the lesion based on the plurality of intravascular images; determine, based on the length of the lesion, a length for a stent to provide treatment for the lesion, wherein the length of the stent and the length of the lesion are distinct from one another, output, to the display, a screen display for planning the stent, wherein the screen display comprises: a visual representation of the blood vessel; and a virtual stent overlaid on the visual representation, wherein the virtual stent comprises the length of the stent.

2. The apparatus of claim 1, wherein the length of the stent is a whole number value and the length of the lesion is a non-whole number value.

3. The apparatus of claim 1, wherein the length of the lesion is not provided in the screen display.

4. The apparatus of claim 1, wherein the length of the stent is displayed before the length of the lesion is displayed.

5. The apparatus of claim 4,2024PF00152 wherein, while the length of the stent is displayed, the processor is configured to receive a user input to display the length of the lesion, wherein the length of the lesion is displayed only after the user input is received.

6. The apparatus of claim 1, wherein, to determine the length of the stent, the processor is configured to retrieve a list of commercially available stent lengths stored in a memory in communication with the processor.

7. The apparatus of claim 6, wherein, to determine the length of the stent, the processor is configured to: compare the length of the lesion to the list of commercially available stent lengths; and select the length of the stent based on the comparison.

8. The apparatus of claim 1, wherein the processor is further configured to obtain a location for the stent, wherein the virtual stent is overlaid at the location on the visual representation.

9. The apparatus of claim 8, wherein, to obtain the location for the stent, the processor is configured to receive a user input representative of a manually-identified location.

10. The apparatus of claim 8, wherein, to obtain the location for the stent, the processor is configured to automatically determine the location for the stent based on at least one of a plurality of vessel metrics or a plurality of lumen metrics for the plurality of intravascular images.

11. The apparatus of claim 10, wherein the location comprises a proximal landing zone and a distal landing zone, wherein a criterion is associated with at least one of the proximal landing zone or the distal landing zone, wherein the criterion comprises at least one of:2024PF00152 a plaque burden of the proximal landing zone being within a threshold value of a plaque burden of the distal landing zone; or both the proximal landing zone and the distal landing zone being at least a threshold distance from significant disease; or an amount of plaque covered by the stent being maximized; or an average plaque burden percentage covered by the stent being maximized; or a combined plaque burden at the proximal and distal landing zones being minimized; or prioritizing additional stent length on the landing zone that is closest to severe disease; or neither the proximal landing zone nor the distal landing zone partially covering a side branch of the blood vessel.

12. An apparatus, comprising: a processor configured for communication with an intravascular imaging catheter and a display, wherein the processor is configured to: control the intravascular imaging catheter to obtain a plurality of intravascular images while the intravascular imaging catheter is moved through a blood vessel of a patient, wherein the blood vessel comprises a lesion; automatically determine a location for a stent to provide treatment for the lesion, wherein the location is determined based on satisfying a criterion associated with at least one of a plurality of vessel metrics or a plurality of lumen metrics for the plurality of intravascular images; and output, to the display, a screen display for planning the stent, wherein the screen display comprises: a visual representation of the blood vessel; and a virtual stent overlaid at the location on the visual representation.

13. The apparatus of claim 12, wherein the location comprises a proximal landing zone and a distal landing zone,2024PF00152 wherein the criterion is associated with at least one of the proximal landing zone or the distal landing zone.

14. The apparatus of claim 13, wherein the criterion comprises at least one of: a plaque burden of the proximal landing zone being within a threshold value of a plaque burden of the distal landing zone; or both the proximal landing zone and the distal landing zone being at least a threshold distance from a plaque burden exceeding the threshold value; or an amount of plaque covered by the stent being maximized; or an average plaque burden percentage covered by the stent being maximized; or a combined plaque burden at the proximal and distal landing zones being minimized; or prioritizing additional stent length on the landing zone that is closest to a location within the lesion that has the greatest plaque burden; or neither the proximal landing zone nor the distal landing zone partially covering a side branch of the blood vessel.

15. The apparatus of claim 12, wherein the processor is further configured to obtain a length for the stent, and wherein the virtual stent comprises the length of the stent.

16. The apparatus of claim 15, wherein, to obtain the length of the stent, the processor is configured to receive a user input representative of a manually-identified length.

17. The apparatus of claim 15, wherein, to obtain the length of the stent, the processor is further configured to automatically determine, based on the plurality of intravascular images, the length of the stent, wherein the length of the stent and a length of the lesion are distinct from one another.

18. The apparatus of claim 17, wherein the length of the stent is a whole number value and the length of the lesion is a non-whole number value.

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