Blocking crossing device

Abstract

A catheter system includes a catheter body, the catheter body including an outer shaft and a rotatable inner shaft. The inner shaft may include one or more imaging sensors for collecting images of the exterior of the catheter body. The catheter body may include one or more windows for providing imaging access to the exterior of the catheter body for the imaging sensor. The distal portion of the catheter body may include a selective bending feature for bending the distal portion in a defined direction. The catheter body may include one or more markers that the imaging sensor may detect to determine the relative orientation of the catheter body.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application entitled “OCCLUSION CROSSING DEVICES” filed on November 16, 2018 and U.S. Provisional Patent Application entitled “OCCLUSION CROSSING DEVICES” filed on April 19, 2018, each of which is incorporated herein by reference in its entirety.

[0003] This application may also be related to a U.S. application entitled “OCCLUSION-CROSSING DEVICES” filed on April 16, 2018, which is a continuation of U.S. application No. 14 / 433,786, entitled “OCCLUSION-CROSSING DEVICES,” filed on April 6, 2015, which is a U.S. national phase application under Section 371 of PCT / US2013 / 064346, entitled “OCCLUSION-CROSSING DEVICES,” filed on October 10, 2013, which claims priority to U.S. Provisional Patent Application No. 61 / 712,149, entitled “OCCLUSION-CROSSING DEVICES,” filed on October 10, 2012, and U.S. Provisional Patent Application No. 61 / 799,505, entitled “OCCLUSION-CROSSING DEVICES,” filed on March 15, 2013. U.S. Application No. 14 / 433,786, filed April 6, 2015, and entitled “OCCLUSION-CROSSING DEVICES,” is also a continuation-in-part of U.S. Patent Application No. 13 / 433,049, filed March 28, 2012 (now U.S. Patent No. 8,644,913), and entitled “OCCLUSION-CROSSING DEVICES, IMAGING, AND ATHERECTOMY DEVICES,” which claims U.S. Provisional Patent Application No. 61 / 468,396, filed March 28, 2011, and entitled “OCCLUSION-CROSSING DEVICES, IMAGING, AND ATHERECTOMY DEVICES,” and filed October 17, 2011, and entitled “OCCLUSION-CROSSING DEVICES, IMAGING, AND ATHERECTOMY DEVICES.” ATHERECTOMYDEVICES," each of which is incorporated herein by reference in its entirety.

[0004] This application may be related to U.S. Patent Application No. 15 / 324,325, filed on January 6, 2017, entitled “HIGH SPEED CHRONIC TOTAL OCCLUSION CROSSING DEVICES,” which is a U.S. national phase application under Section 371 of International Patent Application No. PCT / US2015 / 039585, filed on July 8, 2015, entitled “HIGH SPEED CHRONIC TOTAL OCCLUSION CROSSING DEVICES,” which claims U.S. Provisional Application No. 62 / 022,101, filed on July 8, 2014, entitled “HIGH SPEED CHRONIC TOTAL OCCLUSION CROSSING DEVICES,” and U.S. Provisional Application No. 62 / 022,101, filed on October 31, 2014, entitled “HIGH SPEED CHRONIC TOTAL OCCLUSION CROSSING DEVICES.” CROSSING DEVICES"; each of these patent applications is incorporated herein by reference in its entirety.

[0005] Incorporated by Reference

[0006] All publications and patent applications mentioned in this specification are herein incorporated by reference in their entirety to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. Technical Field

[0007] Catheters are described herein, and in particular, catheters that may include a rotating distal tip having both a directional cutting element and an OCT imaging sensor. Background Art

[0008] Peripheral arterial disease (PAD) and coronary artery disease (CAD) affect millions of people in the United States alone. PAD and CAD are silent and dangerous diseases that can have catastrophic consequences if left untreated. CAD is the leading cause of death in the United States, while PAD is the leading cause of amputation in patients over the age of 50 and is responsible for approximately 160,000 amputations in the United States each year.

[0009] Both coronary artery disease (CAD) and peripheral artery disease (PAD) are caused by the gradual narrowing of blood vessels most often caused by atherosclerosis (the buildup of plaque or fatty material along the lining of the artery walls). Over time, this material becomes hard and thick, which can interfere with blood circulation to the arms, legs, stomach, and kidneys. This narrowing forms a blockage that completely or partially restricts blood flow through the arteries. Blood circulation to the brain and heart can be reduced, increasing the risk of stroke and heart attack.

[0010] Interventional treatments for CAD and PAD may include endarterectomy and / or atherectomy. Endarterectomy is the surgical removal of plaque from a blocked artery to restore or improve blood flow. Endovascular therapies such as atherectomy are generally minimally invasive techniques that open or enlarge narrowed or blocked arteries. Other treatments may include angioplasty to open an artery. For example, balloon angioplasty typically involves inserting a catheter into an artery in the leg or arm and positioning the catheter so that a balloon resides within the blockage. The balloon connected to the catheter is expanded to open the artery. The surgeon can then place a wire mesh tube (called a stent) in the area of ​​the blockage to keep the artery open.

[0011] Such minimally invasive techniques (e.g., atherectomy, angioplasty, etc.) typically involve placing a guidewire across the obstruction. Using the guidewire, one or more invasive devices can be positioned to remove or displace the obstruction. Unfortunately, placement of the guidewire, while important for effective treatment, can be difficult. In particular, when placing a guidewire across an obstruction, it can be difficult to pass the guidewire through the obstruction without damaging the artery. For example, it is often difficult to prevent the guidewire from exiting the lumen into the adventitia and surrounding tissue, which is likely to damage the vessel and prevent effective treatment of the obstruction.

[0012] Therefore, obstruction crossing devices have been developed that are intended to assist in passing through an obstruction. However, many devices are not suitable for use with imaging, making guidewire placement cumbersome and difficult. In addition, many obstruction crossing devices are too large to be used in small diameter peripheral arteries or in coronary arteries. Furthermore, it has been proven difficult to pass the device through an obstruction because the head end of the device, particularly the head end of a rotating device, can deflect away from the obstruction and in some cases enter the wall of the vessel lumen, such as the adventitia. Generally, it is desirable to avoid penetrating the vessel lumen.

[0013] Accordingly, described herein are occluded transcatheter devices that are intended to address some of these related issues. Summary of the invention

[0014] The present invention relates to occlusion crossing devices (e.g., apparatus, systems, etc.) having an outer shaft and an inner shaft that can move within the outer shaft and can rotate relative to the outer shaft to rotate a distal tip region that includes an OCT imaging sensor. These devices can be configured as catheters that include both the inner shaft and the outer shaft; the inner shaft can be removed from the outer shaft to keep the lumen of the outer shaft open so that other elements such as a guidewire or guide catheter can be inserted through the outer shaft.

[0015] Thus, in general, these devices may include an outer shaft having a central channel or cavity extending along the length of the shaft body that opens distally, into which the inner shaft may be inserted so that the head end region of the inner shaft may extend from the distal end of the outer shaft. The inner shaft and the outer shaft may be configured to limit the distal movement of the inner shaft relative to the outer shaft to prevent the outer shaft from extending beyond a predetermined distance from the distal opening of the outer shaft. In general, the devices described herein may be configured as: (1) a guidewire support / placement device (e.g., a catheter); (2) a support / placement imaging device (e.g., a catheter); (3) an occlusion crossing device (e.g., a catheter); or (4) an occlusion crossing imaging device (e.g., a catheter). Any of these devices may include one or more of the elements described herein, and any variation of these devices may be used to treat disease, particularly peripheral arterial disease. A system may include an outer shaft and an inner shaft. In some variations, the device may also include one or more other elements, such as a driver (e.g., for rotating the inner shaft and / or bending the outer shaft or the inner shaft, and / or advancing the inner shaft and / or the outer shaft). For convenience, in the following description, these devices may be referred to as occlusion crossing devices or occlusion crossing catheters.

[0016] In general, the devices described herein may include a flexible, elongated outer shaft, a proximal handle (or handle region), and a flexible, elongated outer shaft having a distal rotating head. The distal rotating head may have a corkscrew-shaped rotating head with a distal central extension configured to guide the head into an obstruction (e.g., to prevent the head from deflecting). The device may also or alternatively include a laterally offset distal-most head (pointed or rounded) on the outer shaft (e.g., on one side of the outer shaft, e.g., at an area of ​​the distal opening of the outer shaft).

[0017] Any device described herein may include one or more tissue separation cutting edges on a rotating distal head; these edges may be formed by a threaded (e.g., grooved) distal region. In some variations, the leading edge of the catheter includes one or more spiral edges, which may be referred to as a wedge. The spiral edge may be arranged at the distal end of the device. The edge may have a small diameter, especially compared to the final diameter of the device. In one embodiment, the rotatable distal head includes a spiral groove that terminates at a distal cutting surface. The distal cutting surface may converge at a tip configured to cut through tissue. The rotatable distal head may also include a distal protruding end having a diameter smaller than that of a more proximal region, which is cylindrical and can help the head end center around the obstruction. Other head designs are also possible. For example, the head end may include a grinding edge and / or a paddle.

[0018] Any device variant described herein may include, for example, a central cavity through an outer shaft, which can be used after removing the inner shaft (e.g., by withdrawing proximally) to place a guide wire through the central cavity to cross the obstruction. The central cavity usually extends to the distal end of the catheter from the region distal to the proximal end or proximal end along the length of the outer shaft. Therefore, the device may include the distal opening mentioned. The opening may be inclined, and / or may be beveled inwardly, which may help visualization (providing a reference on the periphery of the outer shaft) and for centering the outer shaft, so that the entire device is centered in the blood vessel to prevent it from piercing the cavity wall. The central cavity of the outer shaft may be referred to as a guide wire cavity. In some variations, the device is configured to pass through a lesion or obstruction (or one or more obstruction areas of a blood vessel) to position the device to exceed the obstruction before the guide wire passes through the outer shaft. The cavity may be any biological vascular cavity, such as, an artery, a vein, or a delivery tube, such as a peripheral artery, a vein, or a bile duct.

[0019] The device described herein can be configured to apply optical coherence tomography (OCT) to image tissue. Therefore, the device described herein can include an imaging sensor, such as an OCT imaging sensor. The OCT imaging sensor can include the distal end of an optical fiber and a lens for directing light into / out of the optical fiber. The optical fiber can be attached to a distal head structure. The imaging sensor can be oriented to image blood vessels in front of the device, perpendicular to the device, and / or behind the head of the device. A lens or reflector can be used to guide the light path entering and leaving the end of the optical fiber to fix the imaging direction of the device. For example, the optical fiber and the lens can be fixed to the rotating distal head region and can be embedded in a transparent or translucent medium (including transparent glue or other fixatives).

[0020] For example, this document describes a congestion-traversal device, such as a congestion-traversal system. Any of these systems may include any of the following: an outer shaft defining a cavity and a distal opening, the distal opening being inclined relative to the central axis of the outer shaft to form a distal-most tip, and a first engagement region within the cavity; and an inner shaft extending within the cavity and configured to rotate relative to the outer shaft, the inner shaft comprising: a distal end having a grooved tip, the grooved tip being configured to extend through the distal opening; a lateral optical imaging window (e.g., for any imaging technique, such as coherence tomography, OCT) on the side of the inner shaft at the distal region of the inner shaft; and a second engagement region on the outer surface of the inner shaft, the second engagement region being configured to engage with the first engagement region to limit distal movement of the inner shaft within the outer shaft; wherein the distal-most tip of the distal opening is configured to block the OCT imaging window at a defined rotational position when the inner shaft rotates relative to the outer shaft while the first engagement region engages with the second engagement region to provide an alignment mark for OCT imaging.

[0021] In some variations, an occlusion traversal system may include: an outer shaft defining a lumen and a distal opening, the distal opening being inclined relative to a central axis of the outer shaft to form a distal-most tip, a first engagement region within the lumen, and a spine region at a distal portion of the outer shaft, the spine region being configured to offset a lateral bend of the distal portion in a plane including a midline of the central axis and also including the distal-most tip; and an inner shaft extending within the lumen and configured to rotate relative to the outer shaft, the inner shaft comprising: a distal end having a grooved tip, the grooved tip being configured to extend through the distal end opening; a lateral optical coherence tomography (OCT) imaging window on the side of the inner shaft at the distal region of the inner shaft; and a second engagement region on the outer surface of the inner shaft, the second engagement region being configured to engage with the first engagement region to limit the distal movement of the inner shaft within the outer shaft; wherein the distal-most tip of the distal opening is configured to block the OCT imaging window at a defined rotational position when the inner shaft is rotated relative to the outer shaft while the first engagement region is engaged with the second engagement region to provide an alignment mark for OCT imaging indicating the bending direction.

[0022] Any of the devices described herein can be bendable, for example, can include a bend or offset region as part of the outer shaft and / or the inner shaft. For example, any of these devices can include an outer shaft having a spine region at a distal portion of the outer shaft, the spine region being configured to offset a lateral bend of the distal portion. In some variations, the offset direction can be fixed relative to the distal-most head end of the outer shaft. For example, the device can be configured to bend in a plane that includes a midline of the central axis and the distal-most head end.

[0023] As described, the distal opening can be beveled in the circumferential direction. For example, the distal opening can be beveled toward the lumen at an angle with the outside of the outer shaft (e.g., at an angle between about 5 and 80 degrees, about 10 and 70 degrees, about 12 and 60 degrees, about 15 and 50 degrees, etc.).

[0024] In any of these variations, the inner shaft can be configured to be removed proximally from the outer shaft, which leaves an open lumen through the outer shaft. At least on the proximal portion of the outer shaft (excluding the joining area on the inner and outer shafts), the inner shaft outer diameter is generally smaller than the outer shaft outer diameter.

[0025] In general, the inner shaft can be configured so that the distal movement from the distal opening of the outer shaft to the outside is limited. The distal movement can be limited by engaging the first engagement area on the inner wall of the outer shaft with the second engagement area on the outer surface of the inner member. For example, the second engagement area can be a ring, for example, a circular ring with a circular shape. In any of these devices, the distal region of the outer member can have an inner diameter narrower than the more proximal end of the device. The interior and / or the outer member can have a lip or edge (annular belt, annular lip, boss, ramp, etc.), which is wider than the outer diameter of the distal region of the inner shaft (for example, the region of the inner shaft at its distal end), and is also wider than the inner diameter of the distal region of the outer member in diameter, so that the first engagement area on the outer shaft (the region where the inner diameter narrows) engages with the second engagement area on the inner shaft (the region where the outer diameter becomes larger). The first engagement area and the second engagement area are configured so that the inner shaft can be against the outer shaft (for example, can rotate along the outer shaft) with very little friction. For example, one or both surfaces of the engagement region may be configured to reduce friction and / or may be lubricated or may include a lubricant. In some variations, the engagement region (one or both) may include a diamond-like carbon (DLC) coating that forms a hard and smooth chitin layer.

[0026] Additionally, pushing the inner shaft distally so that the second engagement surface is driven distally against the first engagement surface of the outer shaft can bend the distal end of the device in a predetermined direction established by the spinal region, as described in greater detail below.

[0027] Any of the devices described herein may include visualization integrated into the device. For example, any of these devices may include an imaging window (which may include an imaging sensor or an optical fiber connected to an imaging sensor) on one side of the distal region of the inner shaft. In some variations, the lateral imaging window is a lateral optical coherence tomography (OCT) imaging window. For example, any of these devices may include an inner shaft that includes an optical fiber coupled to the OCT imaging window and extending proximally through the inner shaft.

[0028] As described above, any of these devices may include a proximal attachment configured to couple the internal member to the rotational drive and the imaging subsystem. The proximal attachment may be a handle or a base. The proximal attachment may include a drive for driving the rotational movement of the inner shaft; the proximal attachment may alternatively or additionally be coupled to an imaging window (e.g., coupled to an optical fiber) for process imaging.

[0029] Imaging (e.g., OCT imaging) using equipment can be configured to image blood vessels laterally and / or in some variations distally (or laterally and distally) in the distal region of the inner shaft. Because the imaging window can rotate with the head end (e.g., drill bit or grooved head end) of the inner shaft, imaging can provide a panoramic view of the wall of the cavity. In any of these variations, the distalmost head end of the outer shaft can protrude into the visual field of the rotating imaging window when the inner shaft is pushed distally (to the stop position where the first engagement area and the second engagement area are engaged or are about to engage). This protrusion can block a small part of the visual field of the rotating inner shaft (e.g., between about 0.5 degrees and 20 degrees, between about 1 degree and 15 degrees, less than 15 degrees, less than 12 degrees, less than 10 degrees, etc.). The outer shaft can therefore provide a reference (e.g., benchmark) mark on the imaging relative to the blocking of the inner shaft to show the relative position of the outer shaft. This reference frame may be more important when the device is configured (eg, by driving an inner member distally) to bend in a predetermined direction relative to a fiducial (eg, toward or away from a fiducial marker), which may help steer the device.

[0030] Thus, the imaging window (e.g., OCT imaging window) can be a lateral imaging window at or near the distal end of the inner shaft. For example, the lateral imaging window can be adjacent to the grooved tip. In some variations, the lateral (e.g., OCT) imaging window overlaps the grooved tip.

[0031] As described, the distal region of the device (eg, the distal region of the outer shaft) can be configured to bend in a predetermined direction when the second engagement region of the inner member is driven distally against the first engagement region of the outer member.

[0032] Any device described herein can be configured to prevent the device from deflecting away from the obstruction (and possibly entering the cavity wall), and can be particularly configured to allow the distal end of the inner shaft and / or outer shaft to remain centered relative to the target (e.g., obstruction) passed through. At least two of the features briefly described above can be included (together or individually). For example, the distal-most facing head on the outer shaft can help prevent the outer shaft or the outer shaft and the inner shaft from deflecting. In any one of these variations, the distal opening (inclined or perpendicular to the long axis of the outer member) can be circumferentially inwardly beveled from the outer surface of the outer shaft, as described above. This circumferential bevel extending from the outer surface of the outer shaft can also help prevent the deflection of the outer member and / or prevent the outer member from entering the adventitia layer of the vascular cavity. When the outer shaft has the distal-most head as described above, the bevel can be particularly effective.

[0033] Alternatively or additionally, any of these devices can include a protrusion on the threaded distal end of the inner shaft that extends beyond the threaded and / or grooved distal end. The protrusion can extend sufficiently distally (e.g., between about 0.1 mm and about 7 mm, between 0.2 mm and about 5 mm, between about 0.5 mm and about 3 mm, greater than 0.1 mm, greater than about 0.2 mm, greater than about 0.3 mm, greater than about 0.4 mm, greater than about 0.5 mm, greater than about 0.6 mm, greater than about 0.7 mm, greater than about 0.8 mm, greater than about 0.9 mm, etc.). The diameter of the protrusion (over a majority of the protrusion length) can be less than about 75% (e.g., less than about 60%, less than about 50%, less than about 40%, less than about 30%, less than about 25%, less than about 20%, less than about 15%, etc.) of the diameter of the threaded and / or grooved area proximal to the protrusion.

[0034] For example, an occlusion traversal system is described herein, comprising: an outer shaft defining a lumen and a distal opening, and a first engagement region within the lumen; and an inner shaft extending within the lumen and configured to rotate relative to the outer shaft, the inner shaft comprising: a distal end having a first grooved head region configured to extend through the distal opening, wherein the first grooved head region has a first diameter, a second head region extending from the first grooved head region, wherein the diameter of the second head region is less than 60% of the diameter of the first diameter. Any of these systems may also include: a lateral optical coherence tomography (OCT) imaging window on the side of the inner shaft at the distal region of the inner shaft; and a second engagement region on the outer surface of the inner shaft, which is configured to limit distal movement of the inner shaft within the outer shaft.

[0035] A blocking traversal system may include: an outer shaft defining a cavity and a distal opening inclined relative to a central axis of the outer shaft to form a distal-most tip end, and a first engagement region within the cavity; and an inner shaft extending within the cavity and configured to rotate relative to the outer shaft, the inner shaft comprising: a distal end having a first grooved tip end region configured to extend through the distal opening, wherein the first grooved tip end region has a first diameter; a second tip end region extending from the first grooved tip end region, wherein the diameter of the second tip end region is less than 60% of the diameter of the first diameter; a lateral optical coherence tomography (OCT) imaging window on a side of the inner shaft at the distal region of the inner shaft; and a second engagement region on an outer surface of the inner shaft configured to limit distal movement of the inner shaft within the outer shaft; wherein the distal-most tip end of the distal opening is configured to block the OCT imaging window at a defined rotational position when the inner shaft rotates relative to the outer shaft while the first engagement region is engaged with the second engagement region to provide an alignment mark for OCT imaging.

[0036] The first diameter may be substantially the same as the diameter of the inner shaft in a region proximal to the grooved head end region. The second head end region may be grooved and / or threaded and may be formed with grooves or threads of a different pitch, direction or width (groove width) than the first head end region.

[0037] Any of these devices can be configured to bend as described above; for example, the outer shaft can include a spine region at a distal portion of the outer shaft that is configured to bias lateral bending of the distal portion. The distal region of the outer shaft can be configured to bend in a predetermined direction when the second engagement region of the inner member is driven distally against the first engagement region of the outer member.

[0038] The distal opening may be circumferentially beveled as described above.The inner shaft may be configured to be proximally removed from the outer shaft.

[0039] In any variation of the devices including OCT imaging as described herein, the inner shaft can include an optical fiber coupled to the OCT imaging window and extending proximally through the inner shaft. As described, any of these devices can include a proximal attachment configured to couple the inner member to the rotational drive and imaging subsystem, such as coupling the optical fiber to an OCT processing subsystem for OCT imaging. The lateral OCT imaging window can be adjacent to the grooved tip and / or can overlap the grooved tip.

[0040] An occlusion crossing device may include: an outer shaft defining a cavity and a distal opening, the distal opening being inclined relative to a central axis of the outer shaft to form a distal-most tip, wherein the distal opening is beveled circumferentially inward from an outer surface of the outer shaft, and wherein a distal portion of the outer shaft includes a spine extending longitudinally along at least a portion of the outer shaft, wherein the spine is configured to offset a lateral bend of the distal portion; an inner shaft extending within the cavity and configured to rotate relative to the outer shaft, the inner shaft including a distal end having a drill bit configured to extend through the distal opening.

[0041] Any of these devices may include an imaging element coupled to the inner shaft and configured to rotate with the inner shaft. The imaging element may include an optical coherence tomography (OCT) imaging window, or a direct imaging element, such as an imaging sensor (e.g., CCD, etc.). The imaging element may include an optical fiber extending in the inner shaft and substantially along the central axis of the inner shaft.

[0042] As described above, the distal-most tip may be configured to pass in front of the imaging element as the imaging element rotates, forming an alignment mark.The device also includes a handle attached to the inner shaft and the outer shaft and configured to rotate the inner shaft.

[0043] The handle (eg, the proximal attachment, which may be configured as a handle) may be configured to rotate the inner shaft, and thereby the drill bit (eg, the fluted or threaded distal end), at a speed greater than 500 rpm.

[0044] The spine may be part of a selectively flexural support of the outer shaft that at least partially surrounds the flexible tube of the outer shaft.

[0045] Generally speaking, the outer shaft and / or the inner shaft may comprise a braided material. In particular, the flexible tube may comprise a braided material. The braided material may be made of a metallic material surrounded by a polymeric laminate.

[0046] The outer shaft may include a circumferential cut extending at least partially through the thickness of the outer shaft, wherein the spine is between the circumferential cut. The outer shaft may include a plurality of spines. The inner shaft may be removably coupled to the outer shaft.

[0047] For example, an obstruction crossing device may include: an outer shaft comprising: a flexible tube, and a selectively bendable support member at least partially surrounding a distal end of the flexible tube, the selectively bendable support member including a spine extending longitudinally along a portion of the flexible tube, wherein the spine is configured to bias a lateral bend of the distal end of the outer shaft in one direction; and an inner shaft extending within the outer shaft and configured to rotate relative to the outer shaft, the inner shaft having a drill bit extending through an opening at the distal end of the outer shaft. The selectively bendable support member may include a plurality of ribs connected to the spine and surrounding the flexible tube. For example, the selectively bendable support member may include three or more ribs. The flexible tube may include a braided metal material, such as a braided metal material wrapped in a laminate material to make the flexible tube substantially impermeable to fluids.

[0048] Any of these devices may include an optical fiber extending within and coupled to the inner shaft.The optical fiber may include an image sensor configured to sense image data from outside the blockage crossing device.

[0049] In any of these devices, the drill bit may include a window to provide an imaging channel for an image sensor to access the exterior of the blockage crossing device. The inner shaft may be removably coupled to the outer shaft via a connector. In some variations, when a force is applied to the inner shaft in a longitudinal direction, the inner shaft moves longitudinally relative to the outer shaft to cause the distal end of the device to bend in a direction toward the spine.

[0050] In any of the apparatus described herein, at least a portion of the selectively bendable support may radially overlap at least a portion of the drill bit.

[0051] Methods of using any of these devices are also described herein. For example, methods of traversing an obstruction in a blood vessel are described herein. In some variations, the method may include: inserting a catheter into a blood vessel, the catheter comprising an outer shaft and an inner shaft, the outer shaft having a distal opening that is inclined relative to a central axis of the outer shaft to form a distal-most head end, wherein the distal opening is beveled circumferentially inward from an outer surface of the outer shaft, and the inner shaft having a drill bit at the distal end of the catheter; bending the distal portion of the catheter in a transverse direction relative to the central axis of the catheter, wherein the transverse direction is defined by a spine that extends longitudinally along at least a portion of the outer shaft; rotating the inner shaft relative to the outer shaft; moving the catheter distally to traverse an obstruction in a blood vessel; and removing the inner shaft from the outer shaft while the outer shaft remains in the blood vessel.

[0052] Any of these methods may include inserting a guide wire into the outer shaft after removing the inner shaft; these methods may also include using the guide wire to perform an atherectomy procedure.

[0053] Any of these atherectomy procedures may include the use of one or more of balloons, stents, tubes, and medications.

[0054] Generally speaking, the devices described herein are configured so that the inner shaft can be rotated to rotate the grooved head end; the head end can be rotated clockwise or counterclockwise, and depending on the direction and configuration of the grooves or threads in the head end area, can cut into the tissue (blockage) or can push against the tissue (without necessarily cutting). This can be helpful for positioning the device and / or preventing it from penetrating the vessel wall. For example, any method described herein can include rotating the inner shaft in a first direction to penetrate the blockage while advancing, and rotating the inner shaft in a second direction to advance without cutting.

[0055] For example, a method for traversing an obstruction in a blood vessel may include: advancing an outer shaft distally into the blood vessel so that the distal-most tip of the outer shaft is driven distally within the lumen of the blood vessel, the distal-most tip of the outer shaft being formed by an opening of the outer shaft that is inclined relative to a central axis of the outer shaft, wherein the distal opening is beveled circumferentially inward from an outer surface of the outer shaft; advancing an inner shaft distally into the outer shaft until the grooved distal end of the inner shaft extends beyond the distal-most tip to a stop position, at which the inner shaft is restricted from further distal extension from the outer shaft; rotating the inner shaft in a first direction relative to the outer shaft to cut the obstructed tissue; and advancing the outer shaft and the inner shaft distally together to traverse the obstruction.

[0056] For example, a method of traversing an obstruction in a blood vessel may include: advancing an outer shaft distally into the blood vessel so that a distal-most tip of the outer shaft is driven distally within the lumen of the blood vessel, the distal-most tip of the outer shaft being formed by an opening of the outer shaft that is inclined relative to a central axis of the outer shaft, wherein the distal opening is beveled circumferentially inwardly from an outer surface of the outer shaft; advancing an inner shaft distally into the outer shaft until a grooved distal end of the inner shaft extends beyond the distal-most tip to a stop position, at which the inner shaft is restricted from further distal extension from the outer shaft, wherein the grooved distal end of the inner shaft comprises a first grooved head region having a first diameter, and a second grooved head region extending distally from the first grooved head region, the second grooved head region having a second diameter less than 60% of the first diameter; rotating the inner shaft in a first direction relative to the outer shaft to cut the obstructed tissue; rotating the inner shaft in a second direction relative to the outer shaft to engage less of the wall of the blood vessel without cutting; and advancing the outer shaft and the inner shaft together distally to traverse the obstruction while rotating the inner shaft in the first direction. Generally speaking, rotating the inner shaft relative to the outer shaft to cut the obstructed tissue may include advancing the second grooved head region into the obstruction before the remainder of the inner shaft advances into the obstruction to prevent the inner shaft from deflecting as it advances.

[0057] A method for traversing an obstruction in a blood vessel may include: advancing an outer shaft distally into the blood vessel such that a distal-most tip of the outer shaft is driven distally within the lumen of the blood vessel, the distal-most tip of the outer shaft being formed by an opening of the outer shaft that is inclined relative to a central axis of the outer shaft, wherein the distal opening is beveled circumferentially inward from an outer surface of the outer shaft; advancing an inner shaft distally into the outer shaft until a grooved distal end of the inner shaft extends beyond the distal-most tip to a stop position, at which the inner shaft is restricted from further distal extension from the outer shaft; imaging the lumen of the blood vessel through an imaging window on a side of the inner shaft while rotating the inner shaft in a first direction relative to the outer shaft, such that the distal-most tip of the distal opening blocks the imaging window at a defined rotational position when the inner shaft is rotated relative to the outer shaft to provide an alignment mark for imaging; and advancing the outer shaft and inner shaft distally together while rotating the inner shaft in the first direction to traverse the obstruction. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1A-Figure 3B An obstruction crossing device having a selective bending feature is shown.

[0059] Figures 4A-5C A blocking traversal device having separable inner and outer shafts is shown.

[0060] Fig. 6A and Figure 6B is an exemplary block diagram of a drive system for a catheter described herein.

[0061] Figure 7A-7B An exemplary method for detecting the position of a drive shaft of a catheter is shown.

[0062] Figure 8A-B Articulation of an occlusion crossing device with selective bending features and separable inner and outer shafts is shown.

[0063] Fig. 9A and Fig. 9B Shown positioned inside the outer shaft for cutting and imaging Figure 8A-B The inner shaft of the blocking crossing device.

[0064] Fig.10 Shown with the inner shaft removed Figure 8A-B The blocking passes through the outer axis of the device.

[0065] Fig.11A and Fig. 11B Shown with Figure 8A-B An exemplary handle for use with a block crossing device.

[0066] Fig.12 and Fig.13 Shown with Figure 8A-B Another exemplary handle for use with a block crossing device.

[0067] Figure 14A-Figure 14C A distal portion of another embodiment of an occlusion crossing device is shown.

[0068] Fig.15 Shown with a single-track guidewire lumen Figure 1A-Figure 3B The blocking crossing device.

[0069] Fig.16 An exemplary head end for use with a blockage crossing device is shown.

[0070] Fig.17 Another exemplary head end for use with a blockage crossing device is shown.

[0071] Fig.18 Another exemplary head end for use with a blockage crossing device is shown.

[0072] Figures 19A-19D Another exemplary head end for use with a blockage crossing device is shown.

[0073] Figure 20A-20B Another exemplary head end for use with a blockage crossing device is shown.

[0074] Figure 21A-21B Another exemplary head end for use with a blockage crossing device is shown.

[0075] Figure 22A-22C Another exemplary blocked crossing device having selectively bendable supports is shown. Fig.22A Showing a side view, Fig. 22B Shows an exploded perspective view, Fig. 22C A longitudinal cross-section of the blocking crossing device is shown.

[0076] Figure 23A-23C Another exemplary blocked crossing device having selectively bendable supports is shown. Fig.23A Showing a side view, Fig. 23B Shows an exploded perspective view, Fig.23C A longitudinal cross-section of the blocking crossing device is shown.

[0077] Figure 24A-24C Another exemplary blocked crossing device having selectively bendable supports is shown. Fig.24A Showing a side view, Fig. 24B Shows an exploded perspective view, Fig.24C A longitudinal cross-section of the blocking crossing device is shown.

[0078] Fig.25A and Fig.25B Show that it can be replaced Figure 24A-24C Different views of an exemplary collar of a collar of a blocking crossing device are shown.

[0079] Figure 26A-26C Another exemplary obstruction crossing device having an angled outer shaft tip is shown. Fig.26A Showing a side view, Fig.26B Shows an exploded perspective view, Fig.26C A longitudinal cross-section of the blocking crossing device is shown.

[0080] Fig. 27 Imaging using an occlusion crossing device is shown.

[0081] Fig.28A and Fig.28B A perspective view showing an exemplary selectively bendable support member of a block crossing device.

[0082] Fig.29A and Fig.29B A perspective view of another exemplary selectively bendable support member of a block crossing device is shown.

[0083] Fig. 30A and Fig. 30B A perspective view showing an exemplary selectively bendable support member of a block crossing device.

[0084] Fig.31A and Fig.31B An example of a blocked crossing device is shown; Fig.31A A side perspective view showing a blocked crossing device in a curved configuration; Fig.31B Shown by Fig.31A A central cross section of the device.

[0085] Fig.32A Shown without balloon ( Fig.32A ) and balloon use ( Fig.32B ) is an example of an occlusive crossing device, where the balloon can help center the device and / or prevent blood from flowing around the device.

[0086] Figures 33A-33C An example of a blockage crossing device is shown illustrating deflection of the distal end of the device; Fig.33A is slightly deflected, and Fig.33B and Fig.33C Each of them is increasingly deflected.

[0087] Figure 34A-Figure 34D Left, rear, right, and front views, respectively, show the distal end of one example of a device (blocking crossing device) in which an inner shaft extends distally to engage an outer shaft.

[0088] Fig.35 is a cross-sectional view through one example of a blocking traversal device (system), showing an inner shaft having a grooved distal end, and an outer shaft, wherein the inner shaft and the outer shaft are engaged.

[0089] Fig.36 is with Fig.35 An exploded view of the distal portion of one example of a similar occlusion crossing device is shown, illustrating the spine portion of the outer shaft, the distal region of the outer shaft, the OCT imaging window, and the distal end of the inner shaft.

[0090] Figure 37A-Figure 37D The front, right, back, and left views, respectively, illustrate one example of a distal region of an outer shaft showing a distal opening that is tilted relative to a central axis of the outer shaft to form a distal-most tip.

[0091] Fig.37E Showing looking down Figure 37A-Figure 37D Top view of the distal region of the outer shaft of the blocking crossing device.

[0092] Figure 38A-Figure 38D A right side view, a rear view, a left side view, and a front view, respectively, illustrate one example of a distal end region of an inner shaft.

[0093] Fig.38E yes Figure 38A-Figure 38D A rear perspective view of the distal region of the inner shaft.

[0094] Figure 39A-Figure 39DRear, right, front, and left views, respectively, show one example of a grooved distal tip region of an inner shaft.

[0095] Fig.39E Look down Figure 39A-Figure 39D Top view of the grooved distal tip region of the inner shaft. DETAILED DESCRIPTION

[0096] Described herein are occlusion crossing devices (e.g., systems and apparatus) having a low profile that can be used for small diameter arteries and coronary arteries (e.g., through a 5 French catheter or smaller). In general, the devices described herein can have onboard imaging, such as optical coherence tomography (OCT) imaging. The optical fiber used for OCT imaging can extend substantially along the central axis of the device, thereby reducing the profile of the device and allowing rotation at high speeds. The device can also include a rotatable tip to allow forward drilling. In some embodiments, the device can include an articulated distal end to enable steering of the device.

[0097] For convenience, these devices may generally be referred to as catheters or occlusion crossing catheters.It will be appreciated that these catheters may include an outer shaft and a concentrically arranged (and removable) inner shaft.

[0098] Reference Figure 1A-Figure 3BIn one embodiment, an exemplary catheter 100 includes an outer shaft 122 connected to a distal drill bit 103 (also referred to herein as a head end body) and an inner shaft 131 (also referred to as an inner drive shaft). The inner shaft 131 can be configured to be rotatable relative to the outer shaft 122 to rotate the drill bit 103. The elongated outer shaft 122 can be hollow and can have an inner diameter of about 1 mm and an outer diameter of about 1.5 mm. In some embodiments, at least a portion of the outer shaft 122 is flexible. For example, a portion of the outer shaft 122 can include a flexible tube. In some embodiments, at least a portion of the outer shaft 122 can have a coiled configuration, whereby each coil is coiled by twisting one coil on another coil. For example, the outer shaft 122 can include at least two coil layers. In addition, the coil layers can be reversely coiled, such that one coil layer (e.g., an inner coil layer) has a left-hand twist, while another layer (e.g., an outer coil layer) has a right-hand twist. The coils can provide torque in the direction of tightening the outer layer, buckling the inner layer downward. A third counter-wound coil can be added to generate torque in both directions. In another embodiment, at least a portion of the outer shaft 122 is made of a braided material (e.g., a wire or mesh). In yet another embodiment, at least a portion of the outer shaft 122 can be a laser cut tube. In some embodiments, the flexible portion is made of a variety of materials. For example, the flexible portion can include a metal support structure at least partially surrounded by a polymeric material. The support structure (e.g., coiled, braided and / or laser cut material) can be at least partially laminated with the polymeric material (e.g., fused with it). For example, the support structure (e.g., coiled, braided and / or laser cut material) can be embedded in the laminate (e.g., substantially covered by the laminate). In some embodiments, the laminate (e.g., substantially) completely covers all surfaces of the support structure, making the flexible portion of the outer shaft (e.g., substantially) impermeable to fluids. In some embodiments, the outer shaft 122 includes a polymer lining within the braided portion of the outer shaft to reduce friction with the rotating inner shaft 131. The outer shaft 122 can also include one or more imaging windows 144 at its distal end, which will be described in further detail herein.

[0099] The bushing 124 (see Figure 1D ) is attached to the outer shaft 122, such as by a tongue and slot mechanism 148. The bushing 124 can serve as a bearing surface relative to the inner shaft or drill bit 103. In addition, the bushing 124 can include edges or lips 151, 152 on both sides that are configured to interact with the inner drive shaft 131 or drill bit 103, as will be discussed further below.

[0100] The drill bit 103 can be configured to separate, dissect or cut tissue, for example. In some embodiments, the drill bit 103 can include a sharp spiral groove 113 that reaches a point in the center of the device. In addition, the grooves 113 can be tilted so that they have sharper edges when rotated in one direction than when rotated in another direction. As a result, the drill bit 103 with the grooves 113 can have active and passive modes depending on the direction of rotation of the drill bit 103. In the passive mode, the drill bit 103 with the grooves 113 can be less powerful, providing blunt dissection of tissue. In the active mode, the drill bit 103 with the grooves 113 can be more powerful, providing cutting and drilling to pass through harder materials.

[0101] Inner drive shaft 131 (see Figure 1D ) can be connected to the distal drill bit 103 and can extend along the center of the outer shaft 122. The inner drive shaft 131 can be configured to rotate in a single direction or in both clockwise and counterclockwise directions to rotate the drill bit 103 relative to the shaft 122 (around the bushing 124) in a single direction or in both clockwise and counterclockwise directions. Rings 174, 172 can be positioned around the distal portion of the inner drive shaft 131 and / or the drill bit 103. Rings 174, 172 can be positioned against edges 151, 152 of the bushing 124. The annular bushing 124 can allow rotation of the inner drive shaft 131 relative to the bushing 124 while preventing axial movement (and in some embodiments allowing articulation, as further described below). In some embodiments, the inner shaft 131 is configured to rotate in only a single direction. In some embodiments, the inner shaft 131 is configured to rotate in two directions. In some cases, the catheter device includes a control button (or other type of switch) to control the direction of rotation of the inner shaft. In some embodiments, the control button is on the handle.

[0102] The obstruction crossing device described herein may include at least one bendable portion to allow the obstruction crossing device to be manipulated within the blood vessel before, during and / or after crossing the obstruction. For example, the distal end of the obstruction crossing device can be configured to bend laterally in a controlled manner to guide the drill bit to a desired position within the blood vessel. In some cases, the bending is achieved by an articulated feature including a spine. The spine can be a relatively inflexible portion along the length of the device that biases the deflection of the device in one or more lateral directions. In some cases, the spine can be a continuous rib that spans at least a portion of the length of the device. In some cases, the spine is part of an outer shaft. The device may include one spine or multiple spines. In some designs, two or more spines can provide greater lateral stability than one spine.

[0103] exist Figure 1A-Figure 3BIn an example of the present invention, the catheter 100 may include a selective bending feature 145 at a distal portion of the outer shaft 122 selective bending feature. The selective bending feature 145 can be configured to control lateral bending of the distal portion of the outer shaft. The selective bending feature 145 can be coupled to a flexible portion (e.g., a braided or coiled portion) of the outer shaft, which can include a support structure (e.g., a coiled, braided, and / or laser cut material) as described herein. Figure 1A and Figure 1B As shown, the selective bending feature 145 may include one or more spines 245a, 245b and a series of circumferential cuts 247. The circumferential cuts may extend circumferentially partially around the outer shaft between the one or more spines. In some embodiments, the circumferential cuts may be formed by laser cutting. In some cases, the circumferential cuts extend through the thickness of the outer shaft. In some cases, the circumferential cuts extend partially through the thickness of the outer shaft. When force is applied longitudinally and distally to the inner shaft 131, the one or more spines 245a, 245b may cause the outer shaft to preferentially bend laterally toward the spines 245a, 245b. One or more spines may be positioned only on one side of the catheter (e.g., with a span of less than 180 degrees, less than 150 degrees, or less than 90 degrees). In some embodiments, as Figure 1A As shown, a series of small circumferential cutouts 295 may extend between the two spines 245a, 245b to provide increased flexibility during bending. The circumferential cutouts 247, 295 may be configured as an incomplete ring or spiral around the outer shaft 122. Figure 1B In some embodiments, the circumferential ring 247 may include one or more interruptions 297a, 297b therein designed to provide additional tensile strength and compressive resistance to the selective flex feature 145.

[0104] The selective bending feature 145 can be attached to the inner shaft 131 so that movement of the drive shaft 131 can activate the selective bending feature. In addition, in some embodiments, the handle 200 (see Figure 1C , Figure 2B and Figure 3B ) activates movement of inner drive shaft 131. In some embodiments, handle 200 includes one or more activators (e.g., buttons, levers, switches) for controlling the speed and / or direction of inner drive shaft 131. In some cases, handle 200 includes one or more activators (e.g., buttons, levers, switches) for controlling distal and proximal movement of inner drive shaft 131 relative to outer shaft 122.

[0105] Reference Figure 2A-2B As the drive shaft 131 is pushed distally, the ring 172 can be moved around the bushing 124 (see Figure 1D) is pushed distally on the proximal lip 152 of the circumferential cutout 247, causing the circumferential cutout 247 to expand or open while the spines 245a, 245b maintain their length (and the circumferential cutouts 295 close together). As a result, the selective bending feature 145 can bend toward the spines 245a, 245b. Figure 2B As shown, the bending mechanism can be activated on the handle 200, for example, by moving the ring 303 distally and / or pushing or moving a button or lever.

[0106] Similarly, refer to Figure 3A-3B As the drive shaft 131 is pulled proximally, the ring 174 can impact the distal lip 151 of the bushing 124. As the drive shaft 131 applies more distal force, the circumferential cutouts 247 can begin to move closer together and / or the material between the cutouts 247 can overlap while the spines 245a, 245b maintain their lengths (and the cutouts 295 move further apart). As a result, the selective bending feature 145 can bend toward the circumferential cutouts 247 and away from the spines 245a, 245b. Figure 3B As shown, the bending mechanism can be activated on the handle 200, for example, by moving the ring 303 proximally and / or pushing or moving a button or lever.

[0107] The bending motion of the selective bending feature 145 can advantageously allow the device 100 to be turned when used in a blood vessel, such as for reentry in the event that a drill bit is extended out of an obstruction or cavity. In some embodiments, the catheter 100 can be configured to bend in only one direction by pushing or pulling on the drive shaft 131, and return to the desired position by movement of the drive shaft 131 in the opposite direction. Figure 1A Straight configuration shown.

[0108] The catheter 100 may also include an imaging element 199 attached to the drive shaft 131 and configured to rotate therewith. The imaging element 199 may include one or more sensors for collecting image data (e.g., light). The imaging element 199 may be the distal end of an OCT fiber 119 extending along the center of the drive shaft 131. The imaging element 199 may provide imaging (through the window 144) when the catheter 100 is used in a blood vessel, thereby assisting in traversing an obstruction.

[0109] Reference Fig.15, in some embodiments, a single-track guidewire lumen 1505 can extend along the outer shaft 122. The guidewire lumen 1505 can, for example, travel between two spines 245a, 245b to not add additional rigidity to the flexible region with circumferential cutouts 247. In some embodiments, the outer shaft includes more than one guidewire lumen. Therefore, the outer shaft can define at least two cavities: a main lumen for the inner shaft and one or more guidewire cavities for the guidewire. These configurations can allow the inner shaft to remain in the main lumen of the outer shaft 122 while the guidewire (and any invasive device, such as a balloon, stent, tube, medicament, and / or other angioplasty device) uses the guidewire lumen. In some cases, the inner shaft can still be removed from the outer shaft so that the main lumen can also be used for the guidewire.

[0110] In some embodiments, the catheter 100 can be used with a sheath. The sheath can be hollow and include a hemostatic valve attached to the proximal end with a flushing port on the side to facilitate flushing through the sheath. The sheath can also facilitate placement of a guidewire to a target site, particularly for embodiments of the catheter 100 that do not include a single-track guidewire lumen. That is, the catheter 100 can be used to traverse an obstruction, the sheath can be placed above it, the device removed and subsequently the guidewire can be introduced.

[0111] In some embodiments, the catheter devices described herein can be used for procedures other than occlusion crossing. For example, the catheter device can be used for other plaque removal procedures, such as for the placement of balloons, stents, tubes and / or agents. In some cases, the catheter device can be used as an imaging device. For example, a blunt tip (i.e., not designed for occlusion crossing) can be used instead of a drill bit. In some cases, a guide wire or other invasive device is used instead of an inner shaft.

[0112] Alternative drill bit designs for catheter 100 are also possible. In some embodiments, as will be described below with reference to Fig.14A and Fig. 14B As described above, the distal drill bit 103 may have a smooth inclined surface without grooves.

[0113] Fig. 30A and Fig. 30BAn alternative selective bending feature 3045 is shown according to some embodiments. The selective bending feature 3045 can include a proximal end 3007, a distal end 3008, and a cavity 3020 for receiving an inner shaft (e.g., 113). The selective bending feature 3045 is similar to the selective bending feature 145 in that the selective bending feature 3045 can be biased to bend toward the spine 3055. That is, when a compressive load is placed on the selective bending feature 3045, the selective bending feature 3045 bends toward the straight spine 3055. In contrast to the selective bending feature 145, the selective bending feature 3045 can include one spine 3055. The selective bending feature 3045 can also include a cut 3047 (e.g., a laser cut) having a splicing pattern defining tongue elements 3065a, 3065b, 3065c opposite the spine 3055. In some embodiments, the stitching pattern includes a hole 3075 where the cutout 3047 terminates at the spine 3055. The tongue elements 3065a, 3065b, 3065c can have a tapered structure that is configured to dictate the amount of deflection of the selective bending feature 3045 in two directions. For example, the tongue elements 3065a, 3065b, 3065c can force the selective bending features 3045 to lock relative to each other, thereby maintaining the alignment of the selective bending features 3045 and resisting twisting under torsion when deflected. This can also prevent the selective bending feature 3045 from over-bending. Fig. 30A and Fig. 30B As shown, the inner diameter of the selective bending feature 3045 can include an annular boss 3060 that is configured to mate with the end of the flexible portion of the outer shaft. The selective bending feature 3045 can be coupled to the flexible portion of the outer shaft using, for example, welding, adhesives, (multiple) fasteners, or a combination thereof.

[0114] In addition, refer to Fig.16In some embodiments, a distal drill bit 1603 (e.g., for use in place of drill bit 103) can include a tapered body 1660 having a sharp central extension 1616 extending distally from the drill bit 1603. The central extension 1616 can be positioned at the center of the drill bit 1603 (e.g., along the central longitudinal axis of the tip 1603) and can be used to create a pilot hole in the obstruction to guide the remainder of the tip 1603 therethrough. The diameter of the central extension 1616 can be substantially smaller than the diameter of the remainder of the drill bit 1603. For example, the diameter of the central extension 1616 can be 10%-30%, such as 15%-25%, of the diameter of the remainder of the drill bit 1603. Similarly, the length of the central extension 1616 can be approximately 10%-30% (e.g., 15%-35%) of the total length L of the tapered drill bit 1603. Central extension 1616 can be substantially cylindrical with a pointed drill bit thereon. The angle of the pointed tip can extend between 15 and 75 degrees relative to the central longitudinal axis of drill bit 1603, e.g., between 20 and 60 degrees, e.g., between 30 and 45 degrees. In some embodiments, having a minimum angle of 30 degrees at the pointed drill bit ensures that drill bit 1616 does not cut into the side wall of the lumen when traveling through sharp curves (e.g., at the aortic bifurcation). Conversely, in some embodiments, having a maximum angle of 45 degrees ensures that extension 1616 is able to drill into the obstruction (e.g., without being deflected away from the obstruction as would occur with a blunt tip). Fig.16 As shown, drill bit 1603 may also include two or more axially extending grooves 1662 along cone 1660 to create additional cutting edges when drill bit 1603 is rotated through an obstruction. The grooves may continue into extension 1616 to create side grooves therein.

[0115] Fig.17 Another exemplary distal drill bit 1703 is shown, which is similar to the distal drill bit 1603 except that the body 1760 is substantially bullet-shaped (or circular, semicircular). In addition, the central extension 1716 can have a continuous taper from the distal tip to the body 1760, rather than having a cylindrical portion.

[0116] Fig.18 Another exemplary distal drill bit 1803 is shown that is similar to distal tip 1703 except that body 1860 includes one or more helical grooves 1882 extending along body 1760 and extension 1816 .

[0117] The drill bit 103, 1603, 1703, 1803 may have a diameter of, for example, between 4 French and 8 French (between 1 1 / 3 mm and 2 2 / 3 mm).

[0118] Reference Figures 4A-5C In another embodiment, the exemplary catheter 300 includes an inner shaft 311, an outer shaft 322, and a distal drill bit 303 connected to the inner shaft 311. In addition, the outer shaft 322 can be separated from the inner shaft 311. For example, the inner shaft 311 can include one or more connectors that allow the outer shaft 322 to be removed from the inner shaft 311. In some embodiments, the connector is a Luer connector, and other connectors such as valve connectors, connector fittings and / or gasket connectors can certainly be used. The connector can be located anywhere along the catheter. In some embodiments, the connector is near the proximal end, allowing the connector on the proximal end of the outer shaft 322 to be attached or detached from it relative to the handle 900 as described below.

[0119] In some embodiments, the distal portion 313 of the outer shaft 322 can be clear or transparent, for example, made of a clear or transparent plastic, to allow imaging therethrough. In some embodiments, the outer shaft 322 can also include a preformed bend 329 therein to aid in device orientation or steering. Markings 315 (e.g., metal markings) can extend within the distal portion 313 to indicate the relative orientation of the catheter 300 during use. For example, as shown in FIG. Figure 4B As shown, the innermost portion of the bend 329 can be aligned with the marking 315.

[0120] Furthermore, in some embodiments, the inner shaft 311 can be longitudinally moved within the hollow outer shaft 322 by sliding a ring on a handle (e.g., handle 200) connected to the catheter 300 to allow the inner shaft 311 to be exposed (e.g., Figure 4A-4B ) or completely covered (as shown Figure 5A-5C ). In use, the inner shaft 311 can thus extend beyond the outer shaft to aid in drilling through an obstruction and be pulled in when no dissection is required (or when only blunt dissection is required). In some embodiments, the inner shaft 311 can be configured to be fixed at various points relative to the outer shaft 322 to vary the amount of the drill bit 103 that is exposed. In addition, the shaft 311 can be completely removed from the outer shaft 322 to allow a guide wire to be placed therethrough.

[0121] Additionally, the device 300 can include an imaging element 399 similar to that described above with respect to the device 100. The catheter 300 can be configured to utilize the imaging element 399 for imaging both when the inner shaft 311 is extending distally from the outer shaft 322 and when the inner shaft 311 is positioned within the outer shaft 322 (via the transparent distal portion 313).

[0122] The device 300 may include a drill bit 103 similar to any of the drill bits described above with respect to the device 100. However, the drill bit used with the device 300 may have a smaller diameter to fit through the outer shaft 322. For example, the diameter of the drill bit may be less than or equal to 7 French (less than or equal to 2 1 / 3 mm), such as between 1 mm and 2 1 / 3 mm in diameter.

[0123] Figures 19A-19D 19 is an exemplary drill bit 1903 for use with device 300. Drill bit 1903 is similar to drill bit 1803, except that body 1960 is not continuously tapered but includes a proximal cylindrical portion 1965 and a central tapered section 1967. A groove 1982 extends through cylindrical portion 1965, central tapered section 1967, and central extension 1916.

[0124] Figure 20A-20B Another drill bit 2003 is shown. Drill bit 2003 is similar to drill bit 1903, except that it does not include any grooves. Instead, drill bit 2003 includes a cylindrical body 2060 from which a central extension 2016 extends.

[0125] Figure 21A-21B Another drill bit 2103 is shown. Drill bit 2103 is similar to drill bit 1603 except that body 2160 is not continuously tapered but includes a proximal cylindrical portion 2165 and a central tapered recess section 2067. Additionally, extension 2116 is continuously tapered.

[0126] Device 300 may also or alternatively include any of the features, materials, and / or dimensions described above with respect to device 100 .

[0127] Reference Figure 8A-Figure 10 In another embodiment, the exemplary catheter 800 may include a separable inner shaft 811 and outer shaft 822 and a selective bending feature 845 on the distal end of the outer shaft 822 .

[0128] Reference Figure 8A-B , the selective bending feature 845 may include a spine 945 and a series of circumferential cutouts 947. In addition, as Fig. 9AAs shown, the outer shaft 822 may include a collar 860, which may be attached to the selective bending feature 845 of the outer shaft 822. The collar 860 may provide a shape that helps to manipulate the catheter in the blood vessel to the distal end of the outer shaft 822. For example, the collar 860 may have a tapered and / or curved outer surface. The collar may be considered as an extension of the outer shaft 822. For example, the collar may be considered as the distal end of the outer shaft, wherein the distal end (e.g., the collar) may include an aperture for the drill bit 803 to extend through. The collar may be a part of the outer shaft (e.g., formed integrally with the outer shaft) or may be a separate part. In some embodiments, the collar is fixedly coupled to the outer shaft (e.g., by welding, (multiple) fasteners and / or adhesives). In some embodiments, the collar is removably coupled to the outer shaft. In some embodiments, the collar engages with the outer shaft. In some cases, a portion of the collar radially overlaps another portion of the periphery (e.g., fits within it). For example, the inner boss 862 of the collar 860 can fit within a distal portion of the selective bending feature of the outer shaft 822 .

[0129] As described herein, the outer shaft can cooperate with the inner shaft to provide an offset bend in the distal end of the catheter. Figure 8A-Figure 10 In the example of , the inner shaft 811 can be configured to move longitudinally relative to the outer shaft 822. The outer shaft 822 can include an inner boss 862 configured to extend radially inward relative to the outer shaft 822. Similarly, the inner shaft 811 can include an annular member 872, such as a plastic bearing, which has a larger diameter than the rest of the inner shaft 811. Therefore, when the inner shaft 811 is pushed distally, the annular member 872 of the inner shaft 811 can push against the inner boss 862 of the outer shaft 822 (e.g., the collar 860). As a result, the outer shaft 822 can bend toward the spine 945 at the cutout 947 (e.g., Fig. 9A For example, the force applied to the inner shaft 862 can cause the cutout 947 to expand, so that the outer shaft 811 preferentially bends toward the spine 945. This is because the spine 945 is relatively rigid compared to the side of the outer shaft 811 having the cutout 947. If the outer shaft includes multiple spines (e.g., Figure 1A-Figure 3B ), the outer axis will preferentially bend toward the side of the outer axis that has the spine.

[0130] like Fig.10As shown, the inner shaft 811 can be completely removed from the outer shaft 822 and the collar 860 by pulling the inner shaft 811 proximally. In this way, the outer shaft 822 can be used as a sheath, for example, for placing a guide wire. For example, when the inner shaft 811 with the drill bit 803 is used to pass through (e.g., drill through) the obstruction, it can be removed from the outer shaft 811 by pulling the inner shaft 811 (with the drill bit 803) proximally. The guide wire can then be placed in the cavity of the outer shaft 811 where the inner shaft 811 was once located (e.g., pushed through). In this way, the guide wire can be placed through the obstruction. If the guide wire has any interventional device (e.g., a balloon, a stent, a tube, a medicament, and / or other angioplasty device), the interventional device can be used to treat the blocked area of ​​the blood vessel. In some cases, the first intervention is performed using the first guide wire, and the second intervention is performed using the second guide wire. In a specific example, the first guide wire can include a balloon that widens the blood vessel; the first guide wire can then be removed and replaced with the second guide wire to insert the stent.

[0131] In addition, the inner shaft 811 can include an imaging element 877 similar to that described above with respect to the devices 100 and 300 that can rotate with the inner shaft 811. The imaging element 877 can be imaged through the imaging window 866 in the collar 860. In addition, the inner boss 862 can also be used to properly align the imaging element 877 with the imaging window 866 when the inner shaft 811 is within the outer shaft 822.

[0132] Inner shaft 811 may include a rotatable distal drill 803 similar to that described above with respect to devices 100 and 300 (e.g., may include any distal drill design described with respect to devices 100 and 300). Likewise, device 800 may alternatively or additionally include any of the materials and dimensions described above with respect to devices 100 and 300.

[0133] The obstruction crossing device described herein may include a number of features. Figure 11A-11B, the handle 900 can be used to operate the device 800. The handle 900 may include a connector 883 configured to longitudinally connect and lock the inner shaft 811 and the outer shaft 822 together. In some embodiments, the connector 883 is a Luer lock, a valve connector, a joint fitting, or a gasket joint. The connector 883 may be configured to provide a certain relative longitudinal movement between the outer shaft 822 and the inner shaft 811, so that the inner shaft 811 can still move a small distance such as between .125 inches and 0.2 inches to activate the selective bending feature 845. For example, the inner shaft 811 may include an accordion pleat or an elastomeric segment to provide additional relative movement. The actual displacement distance depends on the diameter of the outer shaft of the catheter, the desired curvature, and the elongation / compression of the outer shaft and the inner shaft respectively. The larger the outer shaft diameter, the greater the desired curvature, and the greater the compression / elongation of the shaft, the greater the required displacement amount. In addition, the connector 883 can be configured to allow the inner shaft 811 to rotate freely within the outer shaft to provide rotation of the sharp distal drill bit 803 connected to the inner shaft 811. The connector 883 can be configured so that the outer shaft can rotate relative to the position of the handle. By having the shaft in an articulated position, rotating the outer shaft in use will guide the catheter around or toward an obstacle. If the connector 883 is disconnected, such as Fig. 11B As shown, the inner shaft 811 can be pulled out from the outer shaft 822 by the handle to keep the outer shaft 822 in a proper position, such as for guidewire placement.

[0134] The handle 900 may also include a lever 885 or ring configured to control the axial movement of the inner shaft 811 (and thus the articulation of the device 800). In some embodiments, the lever 885 may include a locking mechanism that allows the device 800 to remain bent at a set angle. The handle 900 may also include a rotation element 893 attached to the outer shaft 822 and configured to rotate the outer shaft 822 (e.g., 360 degrees) to position the bend of the device 800 in a desired orientation.

[0135] Figure 12-13 Another exemplary handle 1000 is shown. Handle 1000 can include many of the features of handle 900. A slide button 1085 can be used to control the axial movement of the inner shaft. Rotation element 1093 can be configured to rotate outer shaft 822.

[0136] In addition, in some embodiments, the connection between the outer shaft and the inner shaft in the handle can be configured so that the two shafts snap together, axially fixing the proximal ends together, but allowing them to rotate independently. In other embodiments, a third element can be used to key, link or nail the two shafts together.

[0137] The features of handles 900 , 1000 , although described as being used with catheter 800 , may likewise be used with any of the catheters described herein.

[0138] Figure 14A-14B The distal end of another embodiment of a catheter 1400 is shown. The catheter 1400 is similar to the catheters 100, 300, 800 except that it includes a smooth distal drill bit 103 and a molded distal portion 1410. Thus, the distal tip 103 can have smooth angled surfaces 1413 that are not grooved and converge at a slightly convex distal tip 1415 (i.e., the drill bit can be frustoconical). Fig.14A , Fig. 14B The distal drill bit 103 may advantageously provide less force to drill through an obstruction. Fig.14A and Fig. 14B The distal drill bit 103 of the present invention can be used to replace any distal drill bit described with respect to catheters 100, 300, and 800. Similarly, catheter 1400 can include a molded distal portion 1422. The molded distal portion 1412 can be similar to the distal end of catheter 300 and can include a sleeve 1424 of the outer shaft, a transparent section 1422, and a selective bending support 1452 (also referred to as a shelf or base). The selective bending support 1452 can be positioned above at least a portion of the flexible portion of the outer shaft (e.g., a braided or coiled portion). In addition, the imaging fiber 1499 can extend along the central axis of the device, as described above with respect to other embodiments. In addition to or in place of the features described with respect to catheter 1400, any features of catheters 100, 300, and 800 can also be used. Similarly, catheter 1400 can be used with a handle having some or all of the features of handles 200, 900, or 1000.

[0139] In some embodiments, all or a portion of the outer shaft of the catheter described herein can be clear to allow imaging therethrough. In addition, in some embodiments, the catheter described herein can include a balloon for occlusion for better imaging. The balloon can be a clear balloon to allow imaging therethrough.

[0140] In some embodiments, the selective bending feature of the outer shaft has the form of a selective bending support that fits over and at least partially surrounds the flexible portion (e.g., a flexible tube) of the outer shaft. That is, at least a portion of the selective bending support can radially overlap the flexible portion of the outer shaft. This configuration is another way to provide a balance between providing flexibility (e.g., bendability) while allowing biased bending of the distal end of the catheter.

[0141] Figure 22A-22CAn exemplary catheter 2200 having a selective bending support 2206 is shown. The catheter 2200, like other catheters described herein, may include an outer shaft having a flexible portion 2204 (e.g., a flexible tube), an inner shaft 2205 configured to be removable from the outer shaft, and a head end body 2210 coupled to the inner shaft 2205. The selective bending support 2206 may extend longitudinally along a portion of the length of the flexible portion 2204 of the outer shaft. In some embodiments, the selective bending support 2206 (and other selective bending supports described herein) may have a length L in a range from about 0.125 inches to about 3 inches. The selective bending support 2206 may be configured to provide selective stiffness to the flexible portion 2204 of the outer shaft at the distal end of the catheter. The selective bending support 2206 may include a proximal portion 2207 and a distal portion 2208 coupled to each other via a spine 2209. The proximal portion 2207 and the distal portion 2208 of the selectively curved support 2206 can each have a shape (e.g., cylindrical) that defines an opening through which a portion of the flexible portion 2204 of the outer shaft fits. That is, the proximal portion 2207 and the distal portion 2208 can surround or enclose at least a portion of the periphery of the flexible portion 2204. The proximal portion 2207 and the distal portion 2208 can be referred to as a rib. The proximal portion 2207 and the distal portion 2208 can be spaced apart from each other so that the flexible portion 2204 of the outer shaft between the proximal portion 2207 and the distal portion 2208 is not covered by the selectively curved support 2206, thereby allowing the side of the outer shaft opposite to the spine 2209 to have greater flexibility for expansion. In some cases, the spine 2209 has a surface shape corresponding to the outer surface of the flexible portion 2204 of the outer shaft. For example, the spine 2209 may have a curved inner surface corresponding to the cylindrical flexible portion 2204 .

[0142] In addition, the spine 2209 can be configured to bias the lateral bending of the catheter 2200. That is, as described with respect to other embodiments herein, the removable inner shaft 2205 can be used to control the bending of the catheter 2200. For example, the head end body 2210 can include an annular lip 2282 that extends radially outward more than any component on the head end 2210 distal to the annular lip 2282. When the inner shaft 2205 is inserted into the outer shaft 2204, the annular lip 2282 can dock with the proximal edge 2284 of the collar 2202. Pushing the inner shaft 2205 further distally can cause the catheter 2200 to bend preferentially in the direction of the spine 2209, because the flexible portion of the outer shaft 2204 can be more flexible and / or retractable than the spine 2209. That is, the spine 2209 provides greater resistance to bending than the flexible portion of the outer shaft between the proximal portion 2207 and the distal portion 2208.

[0143] As with other embodiments described herein, the head end body 2210 can include one or more grooves 2212 (eg, helical grooves) that can help drive the head end body 2210 at least partially through an obstruction as the inner shaft 2205 and the head end body 2210 rotate.

[0144] In some embodiments, the imaging element support 2216 is used to support and / or position the imaging element within the catheter 2200. In some cases, the imaging element support 2216 (which may also be referred to as a "molded lens") has a first surface 2220 that is (e.g., substantially) orthogonal to the axis of rotation of the tip body 2210 and a second surface 2218 that is not orthogonal to the axis of rotation of the tip body 2210. The first surface 2220 can be elongated to support, for example, an optical fiber. The second surface 2218 can be configured to support the distal end of the optical fiber near the window 2214 of the tip body 2210 and deflect the OCT signal into the tissue. An example of such a molded lens is described in Application No. PCT / US2016 / 042152, filed on July 13, 2016, entitled "MICRO-MOLDED ANAMORPHIC REFLECTOR LENS FOR IMAGEGUIDED THERAPETUIC / DIAGNOSTIC CATHETERS," the entire contents of which are incorporated herein by reference.

[0145] exist Figure 22A-22C In the exemplary catheter 2200 of the present invention, the collar 2202 can have a rounded (i.e., convex) and tapered distal outer surface 2222 to give the collar 2202 a bullet-like shape. In some applications, the rounded and tapered shape can allow the collar 2202 and the catheter 2200 to move more easily through an obstruction (e.g., compared to a non-circular and / or non-tapered collar). The degree to which the collar 2202 tapers can be varied in part as required by the application. In one embodiment, the collar 2202 can taper at an angle between 15 degrees and 120 degrees. In addition, the head end can include a radius or a compound form such as an ellipse to produce a tapered element without sharp corners.

[0146] In some embodiments, the head end body 2210 may include a window 2214 that is configured to allow imaging elements (e.g., one or more optical fibers) to approach the outside of the catheter 220 and enter the blood vessel for imaging. The window 2214 may correspond to an opening in the wall of the head end body 2210, which may be open or filled with a signal transmission (e.g., optically transparent) material. The head end body 2210 may be configured to fit within the internal cavity (lumen) of the collar 2202 so that the window 2214 is axially aligned with one or more windows 2223 (e.g., three windows) in the selective bending support 2206. The one or more windows 2223 may be further separated by one or more markers 2224 (e.g., three markers). The inner shaft 2205 may be configured to rotate the head end body 2210 relative to the selective bending support 2206 and the collar 2202 so that the marker 2224 periodically passes in front of the imaging element and is detected by the imaging element. The imaging element can be operatively coupled to a computer (eg, a controller) that is configured to determine the relative orientation of the catheter 2200 using periodic detection of the markers 2224 when in use.

[0147] The distance along the length of the catheter 2200 between the tip 2211 of the tip body 2212 and the center of the window 2214 can be measured as distance D. The distance D can be, for example, 2.5 mm.

[0148] In some embodiments, the catheter includes features that allow the imaging device to be closer to the tip of the tip body (ie, so that Fig.23C The distance D shown is smaller). For illustration, Figure 23A-23C An exemplary catheter 2300 is shown, which is similar to catheter 2200 (including an outer shaft 2304, a removable inner shaft 2305, a rotatable distal body 2310, and a selectively bendable support 2306), except that at least a portion of the shaft ring 2302 is made of a material that allows a signal (e.g., an OCT signal) to be at least partially transmitted therethrough.

[0149] In some embodiments, the collar 2302 is at least partially transparent (optically transparent) to visible light wavelengths. In some embodiments, the collar 2302 is configured to allow at least partial transmission of signals having a wavelength of approximately 1310 nanometers. In some embodiments, the collar 2302 (or a portion thereof) is made of a signal transmitting polymeric material. The signal transmitting collar 2302 can allow an imaging element to be at least partially covered by (overlapping with) the collar 2302 while still being able to detect signals from outside the catheter 2300. For example, referring to Fig.23C, at least a portion of the collar 2302 can axially overlap the distal end of the imaging element support 2316 (e.g., having the imaging element) and overlap the imaging window 2314. Such a configuration can place the imaging element closer to the rotating drill bit 2311 than a configuration in which the imaging element is positioned more proximally. For example, referring to Fig.23C , the distance D between the drill bit 2311 and the center of the window 2314 of the tip body 2310 along the length of the catheter 2300 can be reduced. In some cases, the distance D is reduced by up to or at least about 1 millimeter compared to a configuration in which the imaging element does not overlap the collar axially. In some cases, the distance D is reduced by up to or at least one-third compared to a configuration in which the imaging element does not overlap the collar radially. For example, the distance D can be less than 2 mm. In this example, the drill bit includes a proximal grooved region that extends distally and has a first diameter that is larger than the diameter of a second region 2313, which extends distally from the proximal region and has a smaller diameter; the second region can be pointed and can be used to prevent the end of the drill bit from deflecting from a harder (e.g., calcified) obstruction.

[0150] In some embodiments, the collar 2302 includes a proximal collar portion 2302a and a distal collar portion 2302b. The proximal collar portion 2302a can be configured to prevent light transmission (e.g., opaque), while the distal collar portion 2302b can be configured to allow light to be transmitted therethrough (e.g., transparent). In addition, the proximal portion 2302a can include a tongue 2324 that is radially arranged around the central axis of the proximal collar portion 2302a and is configured to extend within the second collar portion 2302b. In some embodiments, the distal collar portion 2302b and the tongue 2324 can be axially aligned with the imaging element so that the tongue 2324 can be used as a mark when the imaging element is rotated. With reference to the above Figure 22A-22B Like the markings 2224 on the selectively bendable support 2206 described above, the markings 2324 on the collar 2302 can be configured to periodically pass in front of the imaging element as the imaging element rotates to provide information about the relative orientation of the catheter 2300.

[0151] In any occlusion crossing device described herein, the distal end of the outer shaft can include an asymmetrically tapered inclined head end. The asymmetry can be relative to the central axis of the device, such as the central axis of the outer shaft. The asymmetric shape can provide a smoother entry and / or navigation of the device in a blood vessel. The asymmetric shape can also allow the head end to be used as a marker for an optical sensor (e.g., an OCT imaging sensor). The inclined head end can be a part of the outer shaft, or a component of the outer shaft. In some embodiments, the inclined head end is on the collar of the device.

[0152] Figure 26A-26CAn exemplary catheter 2600 is shown in which the collar has an asymmetrical shape. Catheter 2600 is similar to catheter 2200 (including having an outer shaft 2604, a removable inner shaft 2605, a rotatable distal tip body 2610, and selectively bendable supports 2606), except that the distal end 2624 of the collar 2602 is asymmetrically tapered to create an inclined surface of the distal end 2624 of the collar 2602. In some applications, the asymmetrically tapered distal end 2624 can be used as a wedge or bucket configured to help push through an obstruction. In some cases, the asymmetrically tapered distal end 2624 is configured to be used as a marker to help determine the relative orientation of the catheter 2600 during use. For example, as shown in FIG. Fig.26C As shown, a first edge 2680 of the distal end 2624 of the collar 2602 can be configured to axially overlap with the imaging element (in the imaging element support 2316) and / or extend distally beyond the imaging element, while a second edge 2682 of the distal end 2624 of the collar 2602 can be configured not to axially overlap with the imaging element (i.e., be positioned proximal to the imaging element). When the imaging element rotates relative to the collar 2602, the first edge 2680 of the distal end 2624 of the collar 2602 can periodically pass in front of the imaging element, thereby serving as a marker to provide information about the relative orientation of the catheter 2600. One of the advantages of the collar configuration of the catheter 2600 can be that the imaging element can be positioned closer to the tip 2611 of the tip body 2610 compared to other embodiments. In some embodiments, the distance D (between the tip 2611 and the center of the imaging element and / or window 2614) can be less than 1.5 mm (e.g., approximately 1 mm). In some embodiments, the outer surface of the collar 2602 does not have an outer groove. Additionally, in some embodiments, the collar 2602 is not optically clear.As described above in Figures 23 and 24, the distal tip of the drill region may include a region 2613 of smaller diameter that helps prevent the tip from deflecting away from the more rigid blocking material.

[0153] Fig.28A and Fig.28B An alternative selectively curved support member 2806 is shown according to some embodiments. The selectively curved support member 2806 is similar to the selectively curved support member 2206 ( Figure 22A-22C) Similarities may be that the selective bending support 2806 is configured to provide an offset bend of the distal end of the catheter. The selective bending support 2806 includes a spine 2809 connected to a plurality of ribs: a proximal portion 2807, a distal portion 2808, and one or more intermediate ribs 2850. In some embodiments, the distal portion 2808 includes an engagement feature 2820 for engaging with, for example, a collar of an outer shaft. The intermediate rib 2850 may provide torsional strength. For example, the intermediate rib 2850 may provide lateral stability to the selective bending support 2806 (and the distal end of the catheter), thereby providing resistance to torsional forces when the catheter is winding through a blood vessel. Since the ribs are separated, the selective bending support 2806 may still be flexible enough to bend laterally in the direction of the spine 2809. The number, thickness, and spacing between the ribs may vary to achieve a desired compromise between flexibility and torsional strength. In some cases, the spacing between the ribs is determined by the diameter of the shaft flexible portion (e.g., the braided portion) of the outer shaft.

[0154] Fig.29A and Fig.29B Another selectively flexed support 2906 is shown having similar features to selectively flexed support 2806, except that selectively flexed support 2906 has a different configuration of intermediate ribs. For example, intermediate ribs 2950 are thinner than intermediate ribs 2850. In addition, some of intermediate ribs 2950 are connected by connectors 2960. In some embodiments, connectors 2960 can be oriented parallel to spine 2909.

[0155] Any of the catheter variations described herein may include a guidewire lumen as part of or attached to the outer shaft to accommodate a guidewire therein. For example, any of the catheter variations described herein may include a balloon as part of or attached to the outer shaft.

[0156] Fig. 27 2700 can collect image data. As an imaging element (e.g., an OCT fiber) rotates along a central axis of rotation, light can radiate from a distal region of the device 2700 in a circular path 2702. A first portion 2704 of the light can exit the device 2700, while a second portion 2706 of the light can be blocked by one or more markers of the device 2700. Because the markers can be stationary relative to the device 2700 (including the head end body 2708), the markers can be used as a reference regarding the position of the device 2700 (including the head end body 2708).

[0157] In any of the occlusion crossing devices described herein, the imaging element can be configured to image a forward image (in the distal direction). This configuration can be used instead of, or in addition to, a lateral image.

[0158] In some embodiments, the collar can be configured to rotate with the head body. Figure 24A-24C A catheter 2400 is shown, which is similar to catheter 2200 (including an outer shaft 2404, a removable inner shaft 2405, a rotatable distal body 2410, and a selectively bendable support 2406), except that the collar 2402 includes grooves 2442 configured to rotate with the tip body 2410. The grooves 2442 can have substantially the same pitch as the grooves 2412 of the tip body 2410 to provide a substantially continuous cut when the tip body 2410 and the collar 2402 rotate.

[0159] The collar 2402 can be engaged with the head end body 2410 using a locking mechanism, for example. The locking mechanism can be of any type, such as a mechanical lock, a friction lock, or other coupling mechanism. For example, the head end body 2410 can include a first keying member 2430 that is configured to align and engage with a corresponding second keying member 2432 of the collar 2402. In some embodiments, the first keying member 2430 and the second keying member 2432 correspond to tongue and slot features, stepped features, and / or groove and tongue features. The first keying member 2430 and the second keying member 2432 can be positioned at any position on the head end body 2410 and the collar 2402. In some cases, the first keying member 2430 and the second keying member 2432 are on the outer surface (e.g., outer wall) and / or inner surface (e.g., inner wall) of the head end body 2410 and / or the collar 2402. For example, the first keying member 2430 may correspond to a groove or recess on the outer surface of the head end body 2410, and the second keying member 2432 may correspond to a protrusion of the collar 2402 having a shape configured to align with and cooperate with the first keying member 2430 so that the inner surface of the second keying member 2432 engages with the outer surface of the head end body 2410. The rotational movement of the head end body 2410 may lock the collar 2402 with the head end body 2410, thereby causing the collar 2402 to rotate as well. When the head end body 2410 rotates and travels in the forward direction, the resulting pressure between the head end body 2410 and the collar 2402 may further strengthen the engagement of the first keying member 2430 and the second keying member 2432.

[0160] In addition, the collar 2402 can include one or more windows 2434 configured to axially align with the one or more windows 2414 of the tip body 2410 when engaged with the tip body 2410 to provide signaling access to an imaging element external to the catheter 2400. In some cases, the user can be automatically informed when the tip body 2410 and the collar 2402 are not properly aligned and engaged. For example, if the collar 2402 becomes mismatched with the tip body 2410 (i.e., if the tip 2411 is inadvertently pushed proximally relative to the outer shaft 2404), the window 2434 of the collar 2402 will become misaligned with the window 2414 of the tip body 2410, which signal can be detected by the imaging element and sent to one or more controllers as feedback. The distal tip includes a region 2413 having a smaller diameter than the rest of the grooved distal tip.

[0161] In some embodiments, the selectively bendable support 2408 can also include distally extending markers 2424 configured to be axially aligned with the imaging windows 2414 , 2434 to provide information regarding the relative orientation of the catheter 2400 .

[0162] Additionally, in some embodiments, the collar 2402 may be light transmissive (similar to Figure 23A-23C The shaft ring 2302).

[0163] In some embodiments, the head end body and the collar can be configured to weaken the rotation of the head end body in response to a resistance force applied to the head end body. Fig.25A and Fig.25BA collar 2502 is shown that can replace the collar 2402 of the catheter 2400. The collar 2502 can be similar to the collar 2402, except that the second keying member 2532 of the collar 2502 can have a different geometry than the second keying member 2432 of the collar 2402. The second keying member 2532 can have an inclined wall 2590 that is configured to allow the collar 2502 to give when subjected to rotational resistance above a certain amount. For example, an edge (or lip) 2495 of the head end body 2410 can slide along one of the inclined walls 2590 of the collar 2502, so that the first keying member 2430 can be moved out of the first keying member 2430 of the head end body 2410, causing the second keying member 2532 to disengage from the first keying member 2430 (e.g., in some cases slightly moving the collar 2502 laterally relative to the head end body 2410). In this way, when the rotating head body 2410 and the collar 2502 reach the resistance limit, the locking mechanism will be broken, thereby allowing the head body 2410 to rotate without the collar 2502. In some applications, this can advantageously prevent the bunching of tissue that may occur, for example, in the adventitia layer. In some embodiments, the user can determine that the collar 2502 is not rotating and can use it to inform the action (e.g., stop the rotation of the head body 2410 to readjust the catheter 2400 positioning).

[0164] As described above, any catheter described herein may include an imaging element. The imaging element may include an optical fiber, such as an optical coherence tomography (OCT) imaging fiber. The optical fiber may extend within the drive shaft or inner shaft to extend substantially along the central axis of the catheter over the entire length of the optical fiber. The optical fiber may be attached to the distal end and / or distal drill bit of the drive shaft or inner shaft, but may also be freely floating within the drive shaft in other ways. The imaging fiber may transmit OCT signals for imaging the blood vessel in which the device is placed. In some embodiments, the imaging fiber may have a polyimide coating around it within the length of the drive shaft to support and protect the optical fiber as it spins within the drive shaft. In addition, the handle described herein may be configured to accommodate a certain amount of optical fiber slack to facilitate telescoping of the drive shaft relative to the hollow shaft.

[0165] The imaging element may also include a lens oriented at an angle relative to the central axis of the optical fiber (e.g., an angle of 30-60 degrees, such as 45 degrees) so that light emitted from the optical fiber will be reflected from the lens and enter adjacent tissue. An adhesive may be used to hold the distal end of the optical fiber in place. The adhesive may have a refractive index configured to appropriately mismatch the refractive index of the optical fiber, as described in the following documents: U.S. Patent Application No. 12 / 790,703, entitled "OPTICAL COHERENCE TOMOGRAPHY FOR BIOLOGICAL IMAGING", filed on May 28, 2010, and published as US-2010-0305452-A1; and International Patent Application No. PCT / US2013 / 031951, entitled "OPTICAL COHERENCE TOMOGRAPHY WITH GRADED INDEX FIBER FOR BIOLOGICAL IMAGING", filed on March 15, 2013, which are all incorporated herein by reference in their entirety. Additionally, the adhesive can have a meniscus shape along its outer edge, as described in International Patent Application No. PCT / US2013 / 031951, filed on March 15, 2013, entitled "OPTICAL COHERENCE TOMOGRAPHY WITH GRADED INDEX FIBER FOR BIOLOGICAL IMAGING," which is incorporated herein by reference in its entirety. The meniscus shape can advantageously ensure that much less light is reflected from the adhesive surface and back into the optical fiber than would be referenced.

[0166] The drive shaft or inner shaft (and therefore, the imaging element or optical fiber) can be configured to continuously rotate at a high speed in one or both directions, such as greater than 500 rpm, greater than 600 rpm, greater than 700 rpm, greater than 800 rpm, greater than 900 rpm, or greater than 1,000 rpm, such as between 500-1,000 rpm, to provide OCT imaging around the inner circumference of a blood vessel. Such high speed rotation in a single direction or in different directions selected by the user (as opposed to the need to alternately rotate in two directions to manage the optical fiber) allows for more rapid acquisition of image data, thereby providing more accurate and up-to-date images during use of the device 100. For example, images can be generated at a rate greater than 6 frames per second (fps), such as greater than or equal to 8 fps, or greater than or equal to 10 fps, such as approximately 16.67 fps. In an exemplary embodiment, a laser scan rate such as approximately 20 KHz can be configured to keep up with a rate of 16.67 frames per second, approximately 1200 lines per frame.

[0167] Advantageously, because the optical fiber passes through the center of the catheter described herein, the diameter of the catheter can be very small. For example, the outer diameter of the catheter described herein can be less than 0.10", such as less than 0.08", such as less than 0.07", less than 0.06", or less than 0.05". Therefore, the catheter described herein can be advantageously used in small diameter peripheral arteries and cannular arteries.

[0168] In some embodiments, the catheter described herein can be configured to be attached to a drive system. The drive system can include a rotating optical junction configured to rotate an optical fiber. Exemplary drive systems that can be used in conjunction with the devices herein are described in the following documents: U.S. Patent Application No. 13 / 654,357, entitled "ATHERECTOMY CATHETERS AND NON-CONTACT ACTUATION MECHANISM FOR CATHETERS", filed on October 17, 2012, and International Patent Application No. PCT / US2013 / 032089, entitled "ATHERECTOMY CATHETER DRIVE ASSEMBLIES", filed on March 15, 2013, each of which is incorporated herein by reference in its entirety.

[0169] In some embodiments, the drive system can communicate with the control system via a communication bus, which in some embodiments can be a CAN bus 2.0B. This communication can be used to transmit status, such as direction, speed, operating status, and other information to the control system or console. It can also be used to send control information to the drive system, such as operating commands, speed, direction, and settings for parameters used to compensate for the mechanical characteristics of the catheter. Fig. 6A , in one embodiment, a drive processor 1601 is used as the primary control element of the drive system. The drive processor 1601 controls the motor 1603 through a motor controller 1602, which receives commands and returns status from / to the drive processor 1601. The drive processor 1601 can also implement algorithms to optimize catheter performance in addition to simple speed and direction control. The drive processor 1601 communicates with the control system (e.g., the control console of the device) via a CAN controller 1604 to send and receive commands and status. In addition, in this embodiment, a switch 1605 on the housing of the drive processor 1601 allows local control of the operating state. The switch 1605 can be replaced by an alternative hardware input such as a button, a toggle key, or a knob.

[0170] Furthermore, in some embodiments, the drive system can communicate with the catheter via NFC or RFID to obtain information about the catheter. As an example, this information may include catheter type, optimal rotation speed and direction, serial number, among many possible parameters. Figure 6B , the drive system communicates with the catheter via the NFC / RFID reader 1606 and the NFC / RFID tag 1607 in the catheter to obtain the information stored in the tag.

[0171] The drive system can be configured to allow the drive shaft and cutter to continuously rotate clockwise or counterclockwise according to user preference. Therefore, in some embodiments, the drive system can include a user-accessible switch such as a toggle key to set the desired direction.

[0172] Additionally, in some embodiments, the drive system may include a mechanism to determine the amount of rotation of the drive shaft in a clockwise or counterclockwise direction. Fig. 6A and Figure 6B In one embodiment, for example, the drive system can provide information about the direction of the motor. The speed and direction can be sensed by the control system (or console) through the data lines in the temporary cable (which can be dedicated lines or multiplexed signals). The dedicated lines can carry analog or digital signals. In one embodiment, the dedicated voltage lines carry six discrete speeds (vector speed+direction) that are interpreted by the control system or console to infer the speed and direction of the catheter.

[0173] Reference Figure 7A-7B In one embodiment, the markers in the drive system may include an asymmetric design or asymmetric positioning of the markers around the motor (see Fig. 7A ). The controller can then sense the motor direction by detecting different sequences of marker spacing and / or width, e.g. Figure 7B shown.

[0174] Furthermore, in some embodiments, the drive system may be configured to rotate the drive shaft at a number of discrete rates and / or include a knob to allow a user to select a continuously variable speed.

[0175] Any of the catheters described herein may be shaped, or include shape-setting features to enhance trackability and navigability.

[0176] As used herein, an imaging element may include an OCT fiber (such as the distal end of the fiber) as well as a lens and an adhesive for holding the lens and fiber in place.

[0177] As described above, the catheters described herein may include optical coherence tomography imaging, such as common path OCT. Such OCT systems are described in the following documents: U.S. Patent Application No. 12 / 829,267, filed on July 1, 2010, entitled "CATHETER-BASED OFF-AXISOPTICAL COHERENCE TOMOGRAPHY IMAGING SYSTEM," Publication No. US-2010-0021926-A1; U.S. Patent Application No. 12 / 790,703, filed on May 28, 2010, entitled "OPTICAL COHERENCE TOMOGRAPHY FOR BIOLOGICAL IMAGING," Publication No. US-2010-0305452-A1; and U.S. Patent Application No. 12 / 136,694, filed on March 15, 2013, entitled "OPTICAL COHERENCE TOMOGRAPHY WITH GRADED INDEXFIBER FOR BIOLOGICAL IMAGING." IMAGING”, the entire contents of which are incorporated by reference in their entirety. Alternatively, other types of imaging can be used with the catheters described herein. For example, the devices described herein can be configured to work with infrared spectrometers or ultrasound.

[0178] The catheters described herein can be used to traverse obstructions within a blood vessel. Advantageously, the devices can advantageously provide increased trackability during these traversals through bends / turns and high imaging speeds.

[0179] Although the features of the catheters described herein are shown with respect to specific examples, it will be understood that some or all of the features of the catheters herein may be combined with some or all of the features of one or more other catheters described herein. For example, any drill bit described herein with respect to one embodiment may replace any drill bit described with respect to another embodiment. Additionally, any feature described with respect to one catheter may be combined with or replace any feature described with respect to another catheter.

[0180] Example

[0181] Figure 31A-Figure 31B An example of a blockage crossing device (e.g., a blockage crossing system) incorporating some of the above features is shown. Fig.31A In the embodiment, the blocking traversal system 3100 includes an outer shaft 3101, and the outer shaft 3101 includes an inner cavity 3107 (in Fig.31B31). The outer shaft also includes a distal opening 3109, which is inclined relative to the central axis of the outer shaft 3111 to form a distal-most head end 3113. The device also includes an inner shaft 3103, which extends within the cavity and is configured to rotate relative to the outer shaft. The inner shaft includes a distal end having a grooved head end 3133, which is configured to extend through the distal opening. The distal end of the inner shaft also includes a lateral optical coherence tomography (OCT) imaging window 3135 on the side of the inner shaft at the distal region of the inner shaft.

[0182] The distal-most tip of the distal opening is configured to block the OCT imaging window at a defined rotational position to provide an alignment mark for OCT imaging when the inner shaft rotates relative to the outer shaft while the first engagement region is engaged with the second engagement region.

[0183] exist Fig.31B In the cross-section through the centerline of the device, Fig.31A The proximal end of the device is not shown, but may include a proximal attachment configured to couple the internal member to a rotational drive and an imaging subsystem (eg, for OCT imaging).

[0184] The outer shaft in this example also includes a spine region 3141 at the distal portion of the outer shaft configured to bias the lateral curvature of the distal portion. The bias can be in a plane including the midline of the central axis and the distal-most tip; Fig.31B In , the plane is the plane of the cross section (e.g., the midline that bisects the distal tip and passes through the central axis 3111). Fig.31A and Fig.31B , the distal end of the device is shown as curved. In some variations, the distal region of the outer shaft can be configured to bend in a predetermined direction when the inner member is driven distally beyond a stop position relative to the outer member. Alternatively, the outer member and / or the inner member can be biased to bend in a relaxed configuration and can be controllably straightened, for example, by driving the inner member distally.

[0185] The distal opening of the distal end of the outer shaft is beveled circumferentially, as will be described in greater detail below, such that it appears as a frustoconical region (cut at an angle to the midline of the central axis to form a distal-most tip).

[0186] In this example, the inner shaft is configured to be removed proximally from the outer shaft (not shown), for example, by withdrawing the inner shaft proximally to pull it out of the outer shaft. The inner shaft is prevented from extending too far from the outer shaft by engagement between a region of the outer shaft (the first engagement region) and a region of the inner shaft (the second engagement region), as will be shown in more detail below.

[0187] Fig.32A and Fig.32BAnother example of a blocking crossing device (eg, blocking crossing system) is shown, which is Figure 31A-Figure 31B The device shown is similar, but may also include a balloon 3215. The balloon may be attached to the exterior of the outer shaft (e.g., over all or a portion of the spinal region 3241). Fig.32A In the middle, the balloon is not inflated; Fig.32B An inflated balloon is shown. The balloon may be oversized to occlude the vessel (prevent or restrict blood flow) and may be inflated by saline from the proximal end (not shown).

[0188] Figure 33A-Figure 33C Shown with Figure 31A-Figure 31B The inner shaft 3305 and the outer shaft 3303 can both bend together. In this example, the inner shaft can flexibly follow the bending of the outer shaft, and the outer shaft includes a spine region 3317 (at Fig.33B ), which can guide the bending in a defined plane (in this example, the paper plane).

[0189] Figure 34A-Figure 34D Shown above Figure 31A-Figure 31B 34 is an enlarged view of a similar blocking crossing device shown. In this example, the distal end of the outer shaft is formed by a rigid collar 3406, which includes an opening at the distal end, and a grooved distal end of an inner shaft 3608 (e.g., a drill bit of an inner member) extends out of the opening. The grooved distal end extends from the distal opening until the internal stop is engaged. The distal opening of the distal end of the outer shaft (e.g., formed by the rigid collar) is beveled inwardly at an angle α toward the inner cavity, as shown in FIG. Fig.34A As shown (for example, the outer member is beveled in the circumferential direction). Figure 34A-Figure 34D The same in the embodiment, but can be different in the perimeter. In this example, the angle is between about 25-35 degrees (e.g., 30 degrees).

[0190] The threaded or grooved distal end 3410 of the inner shaft surrounds a region having a first diameter D1, and a second distal region 3412 having a second diameter D2 extends from the first region. Fig.32A shown. Figure 34B-Figure 34D Shows views from different sides of the same distal tip. Fig.34B , the rear view shows the distal-most tip end 3422 of the distal opening of the outer shaft.

[0191] Fig.34DAn example of a lateral optical coherence tomography (OCT) imaging window 3432 is shown. As shown in this example, the imaging window is below the height of the distal-most end 3422 of the outer shaft. In operation, the inner shaft rotates while imaging through the lateral window; therefore, for each rotation, the imaging window will be temporarily blocked by the distal-most end of the outer shaft. As described above, this provides an indication of the orientation of the device relative to the image (the lumen of the vessel). This can be used for raw image viewing, but can also be used when processing images to reduce noise or drift.

[0192] In general, the inner shaft can be rotated relative to the outer shaft at any suitable speed and in either a clockwise or counterclockwise direction. The direction of rotation can advantageously be used to position the distal end of the device, because the grooved distal end of the inner shaft can be rotated in a first direction (e.g., counterclockwise) to engage the sharp wedge of the groove to cut tissue, or can be rotated in a second (e.g., clockwise) direction that is less cutting / less traumatic. Since imaging (e.g., OCT imaging) can occur while rotating, it may be desirable in some cases to rotate the grooved distal tip for imaging even if cutting of tissue is not desired.

[0193] Fig.35 The distal end of the device (e.g., Figure 34A-Figure 34D An example of a cross section of the distal end shown in FIG. Fig.35 As shown, the inner shaft 3505 can advance distally within the outer shaft 3503 so that the grooved distal end 3508 extends from the distal opening of the outer shaft. The inner shaft can advance until the engagement area of ​​the inner shaft 3519 (which is shown as an annular area having a larger outer diameter than the rest of the inner shaft) engages against the engagement area 3521 on the inner cavity of the outer shaft (shown here as an area of ​​narrowed diameter near the distal end of the outer shaft). In this example, the engagement area of ​​the inner shaft can rotate against the engagement area of ​​the outer shaft so that the inner shaft can rotate freely relative to the outer shaft. The area may include a lubricant and / or may be coated with a lubricating material or formed with a lubricating material. In some variations, one or both of these two surfaces may include small channels or cut-out areas that form a fluid bearing. Although Fig.35 The engagement area of ​​the inner shaft is shown as a circular ring, but other configurations may be used, such as multiple discrete areas rather than a continuous ring. Fig.35 In the embodiment, the inner shaft also includes an optical fiber line 3526 extending along the length of the inner shaft, which is distally connected to the OCT imaging window 3536 and can form a part of the imaging window.

[0194] Fig.36 Show Figure 34A-Figure 34D, which includes: a spinal region of the outer shaft 3603, a distal region 3604 of the outer shaft including the distal-most tip, an OCT imaging window 3617, and a grooved distal region 3603 of the inner shaft. The distal region of the inner shaft also includes an annular engagement region 3619.

[0195] Figure 37A-Figure 37D A rotated view of the distal end of the outer shaft is shown formed as a rigid collar 3706 including an opening at the distal end 3708 as described above and a circumferential ramp 3716. The distal end of the outer shaft also includes a distal-most tip 3719.

[0196] Figure 38A-Figure 38D An example of a distal region of an inner shaft is shown, showing a grooved head end region 3844 configured to extend through a distal opening of an outer shaft. The grooved head end region has a first grooved head end portion 3847 having a first diameter D1, and a second head end region 3845 extending from the first grooved head end region. The diameter D2 of the second head end region is less than 60% of the diameter of the first diameter (in this example, it is less than 40% of D1). The distal end of the inner shaft may also include a lateral optical coherence tomography (OCT) imaging window 3814 on the side of the inner shaft at the distal region of the inner shaft. The imaging window can be positioned distally, for example, adjacent to the grooved region or overlapping the grooved region, as shown. In the figure, Figure 38A-Figure 38D In the embodiment, the distal region of the inner shaft also includes an annular engagement region 3824 on the outer surface of the inner shaft, which can limit the distal movement of the inner shaft within the outer shaft when it is engaged with the inner engagement region of the outer shaft, as described above in Fig.35 As described in. Fig.38E Shows Figure 38A-Figure 38D A posterior perspective view of the same distal region shown in FIG.

[0197] Figure 39A-Figure 39D Additional details on the grooved distal region of the inner shaft are shown, with Figure 38A-Figure 38D The illustrated embodiment is similar, including a more proximal grooved region and a distal protrusion having a smaller diameter and in this example becoming a point. Fig.39E Shown is a top view looking down at the grooved distal end of the inner shaft. Fig.39E The top view shows the relative diameter D1 3953 of the first grooved area and the relative diameter D2 3951 of the second grooved area.

[0198] As used herein in the specification and claims, including in the examples, unless expressly stated otherwise, all numbers may be read as if preceded by the word "about" or "approximately", even if the word does not explicitly appear. When describing an amplitude and / or position, the words "about" or "approximately" may be used to indicate that the value and / or position described is within a reasonable expected range of values ​​and / or positions. For example, a numerical value may have a value that is + / -0.1% of a specified value (or range of values), + / -1% of a specified value (or range of values), + / -2% of a specified value (or range of values), + / -5% of a specified value (or range of values), + / -10% of a specified value (or range of values), etc. Any numerical range described herein is intended to include all subranges contained therein.

[0199] Other details related to the present invention, including materials and manufacturing techniques, can be used within the level of a person skilled in the relevant art. This also applies to the method-based aspects of the present invention in terms of additional actions that are usually or logically adopted. Moreover, it is contemplated that any optional features of the described invention variations can be independently proposed or claimed, or combined with any one or more of the features described herein. Similarly, when referring to singular items, the possibility of multiple identical items is included. More specifically, as used herein and in the appended claims, the singular forms "one", "an", "said" and "the" include plural concepts unless the context clearly dictates otherwise. It should be further noted that the claims can be written to exclude any optional elements. Therefore, this statement is intended to serve as a prior basis for the use of exclusive terms such as "solely", "only" and the like related to the recording of the claims or the use of "negative" limitations. Unless otherwise defined herein, all technical and scientific terms used herein have the same meaning as those generally understood by ordinary technicians in the field to which the invention belongs. In the technical field to which the present invention aspires, the breadth of the present invention is not limited by the examples described herein, but only by the simple meaning of the claim terms used.

Claims

1. A blocking crossing system, comprising: an outer shaft defining a lumen and a distal opening angled relative to a central axis of the outer shaft to form a distal-most tip, and a first engagement region within the lumen; as well as an inner shaft extending within the lumen and configured to rotate relative to the outer shaft, the inner shaft comprising: a distal end having a grooved tip, the grooved tip configured to extend through the distal opening; a lateral optical coherence tomography (OCT) imaging window on a side of the inner shaft at a distal region of the inner shaft; and a second engagement region on an outer surface of the inner shaft, the second engagement region configured to engage with the first engagement region to limit distal movement of the inner shaft within the outer shaft; Wherein, the distal-most head end of the distal opening is configured to be able to: block the lateral optical coherence tomography imaging window at a defined rotational position when the inner shaft rotates relative to the outer shaft while the first engagement region is engaged with the second engagement region, so as to provide an alignment mark for lateral optical coherence tomography imaging.

2. The system according to claim 1, wherein: The outer shaft includes a spine region at a distal portion of the outer shaft, the spine region configured to bias lateral curvature of the distal portion in a plane including a midline of the central axis and the distal-most tip.

3. The system according to claim 1, wherein: The distal opening is beveled in the circumferential direction.

4. The system according to claim 1, wherein: The inner shaft is configured to be proximally removable from the outer shaft.

5. The system according to claim 1, wherein: The second engagement region comprises a ring having a circular outer shape.

6. The system according to claim 1, wherein: The inner shaft includes an optical fiber coupled to the lateral OCT imaging window and extending proximally through the inner shaft.

7. The system of claim 1 further comprising a proximal attachment configured to couple the internal member to the rotary drive and the imaging subsystem.

8. The system according to claim 1, wherein: The lateral optical coherence tomography imaging window is adjacent to the grooved head end.

9. The system according to claim 1, wherein: The lateral optical coherence tomography imaging window overlaps the grooved head end.

10. The system according to claim 1, wherein: The distal end region of the outer shaft is configured to bend in a predetermined direction when the second engagement region of the inner member is driven distally against the first engagement region of the outer member.

11. The system according to claim 1, wherein: The first engagement region includes an annular lip.

12. A blocking crossing system, comprising: an outer shaft defining a lumen and a distal opening, the distal opening being angled relative to a central axis of the outer shaft to form a distal-most tip end, a first engagement region within the lumen, and a spine region at a distal region of the outer shaft, the spine region being configured to bias lateral curvature of the distal portion in a plane including a midline of the central axis and also including the distal-most tip end; as well as an inner shaft extending within the lumen and configured to rotate relative to the outer shaft, the inner shaft comprising: a distal end having a grooved tip, the grooved tip configured to extend through the distal opening; a lateral optical coherence tomography (OCT) imaging window on a side of the inner shaft at a distal region of the inner shaft; and a second engagement region on an outer surface of the inner shaft, the second engagement region configured to engage with the first engagement region to limit distal movement of the inner shaft within the outer shaft; Wherein, the distal-most head end of the distal opening is configured to be able to: block the lateral optical coherence tomography imaging window at a defined rotational position when the inner shaft rotates relative to the outer shaft while the first engagement area is engaged with the second engagement area, so as to provide an alignment mark for the lateral optical coherence tomography imaging indicating the bending direction.

13. A blocking crossing system, comprising: an outer shaft defining a lumen and a distal opening, and a first engagement region within the lumen; as well as an inner shaft extending within the cavity and configured to be rotatable relative to the outer shaft, the inner shaft comprising: a distal end having a first grooved head region configured to extend through the distal opening, wherein the first grooved head region has a first diameter, a second head end region extending from the first grooved head end region, wherein a diameter of the second head end region is less than 60% of a diameter of the first diameter, a lateral optical coherence tomography (OCT) imaging window on a side of the inner shaft at a distal region of the inner shaft, and A second engagement region is provided on an outer surface of the inner shaft, the second engagement region being configured to limit distal movement of the inner shaft within the outer shaft.

14. The system according to claim 13, wherein: The first diameter is the same as a diameter of the inner shaft in a region proximal to the grooved head end region.

15. The system of claim 13, wherein: The second head end region is grooved.

16. The system of claim 13, wherein: The second head end region extends to a point.

17. The system of claim 13, wherein: The outer shaft includes a spine region at a distal portion of the outer shaft, the spine region being configured to bias lateral curvature of the distal portion.

18. The system of claim 13, wherein: The distal opening is beveled in the circumferential direction.

19. The system of claim 13, wherein: The inner shaft is configured to be proximally removable from the outer shaft.

20. The system of claim 13, wherein: The second engagement region comprises a ring having a circular outer shape.

21. The system of claim 13, wherein: The inner shaft includes an optical fiber coupled to the lateral OCT imaging window and extending proximally through the inner shaft.

22. The system of claim 13, further comprising a proximal attachment configured to couple the internal member to the rotary drive and the imaging subsystem.

23. The system of claim 13, wherein: The lateral optical coherence tomography imaging window is adjacent to the grooved head end.

24. The system of claim 13, wherein: The lateral optical coherence tomography imaging window overlaps the grooved head end.

25. The system of claim 13, wherein: The distal end region of the outer shaft is configured to bend in a predetermined direction when the second engagement region of the inner member is driven distally against the first engagement region of the outer member.

26. A blocking crossing system, the system comprising: an outer shaft defining a lumen and a distal opening angled relative to a central axis of the outer shaft to form a distal-most tip, and a first engagement region within the lumen; as well as an inner shaft extending within the cavity and configured to be rotatable relative to the outer shaft, the inner shaft comprising: a distal end having a first grooved head region configured to extend through the distal opening, wherein the first grooved head region has a first diameter, a second head end region extending from the first grooved head end region, wherein a diameter of the second head end region is less than 60% of a diameter of the first diameter, a lateral optical coherence tomography (OCT) imaging window on a side of the inner shaft at a distal region of the inner shaft, and a second engagement region on an outer surface of the inner shaft, the second engagement region being configured to limit distal movement of the inner shaft within the outer shaft; Wherein, the distal-most head end of the distal opening is configured to be able to: block the lateral optical coherence tomography imaging window at a defined rotational position when the inner shaft rotates relative to the outer shaft while the first engagement region is engaged with the second engagement region, so as to provide an alignment mark for lateral optical coherence tomography imaging.

Images