Devices and methods for preventing thromboembolism and resection

Abstract

A reversing tube device has a reversing tube (e.g., a knitted tube) configured to roll into a reversing support catheter and capture material from inside a body cavity (such as a blood vessel), wherein the knitted tube is configured to prevent downward locking onto the outside of the reversing support catheter. The reversing support catheter may include an expandable funnel at its distal end having an internal profile adapted to capture and disintegrate rigid material captured by a retractor so that it can be pulled into the reversing support catheter for removal.

Description

[0001] By referencing the merging

[0002] All patent application publications and granted patents specified in this specification are incorporated herein by reference to the extent that each individual publication or patent is specifically and individually indicated to be incorporated by reference. Technical Field

[0003] The devices and methods described herein relate to the mechanical removal of material from inside a body cavity. For example, a mechanical thrombectomy device and method are described herein. Background Technology

[0004] The goal is often to remove tissue from the body in the most minimally invasive way possible, without damaging other tissues. For example, removing tissue (such as blood clots) from inside blood vessels can improve a patient's condition and quality of life.

[0005] Many vascular problems stem from insufficient blood flow through the blood vessels. One cause of insufficient or irregular blood flow is a blockage inside the blood vessels (called a blood clot or thrombus). Blood clots can occur for many reasons, including after trauma (such as surgery) or due to other causes. For example, in the United States, a large percentage of the more than 1.2 million heart attacks are caused by blood clots (thrombi) that form inside the coronary arteries.

[0006] When a blood clot forms, it effectively stops blood flow through the area where the clot forms. If the clot extends across the inner diameter of an artery, it can block blood flow through that artery. If a coronary artery is 100% thrombosed, blood flow in that artery stops, leading to a shortage of oxygen-carrying red blood cells (e.g., the muscle that supplies oxygen to the heart walls). This clot is unnecessary to prevent blood loss but can be undesirably caused by damage to the arterial wall caused by atherosclerotic disease within the artery. Therefore, the underlying atherosclerotic disease does not cause acute hypoxia (ischemia) but can cause acute ischemia via the resulting clot. Similarly, a clot in a carotid artery can cause a stroke due to insufficient oxygen supply to important nerve centers in the head. Hypoxia reduces or prevents muscle activity, causing chest pain (angina) and can lead to myocardial death, permanently disabling the heart. If myocardial cells die extensively, the heart will be unable to pump enough blood to meet the body's life-sustaining needs. The degree of ischemia is influenced by many factors, including the presence of collateral vessels and blood flow, which can provide the necessary oxygen.

[0007] Clinical data suggest that clot removal can be beneficial or even essential for improving treatment outcomes. For example, in peripheral blood vessels, interventional and surgical procedures can reduce the need for amputation by 80%. The ultimate goal of any treatment for these diseases of the arterial or venous system is to rapidly, safely, and most effectively remove the blockage or restore patency. This can be achieved through thrombolysis, fracturing, thrombus aspiration, or a combination of these methods.

[0008] Existing devices for removing materials (including clots) from inside body cavities often face difficulties in removing large quantities of material and / or hard or rigid materials. Mechanical devices used for removing such materials can become clogged or blocked. Furthermore, they can lock up when in use.

[0009] Examples of devices including inverted tubes for removing material from body cavities (e.g., for removing clots from blood vessels, such as thrombectomy devices) are disclosed and described in U.S. Patent No. 10,271,864, and U.S. Patent Application Publications 2019 / 0117214, 2018 / 0042626, and 2018 / 0042624, and U.S. Patent Application Serial No. 16 / 566,393. These devices perform well in removing material from inside blood vessels, but face challenges in some situations when using longer inverted tubes, specifically when using tightly fitted inverted supports. When a knitted inverted tube is placed above a catheter, such as when it is confined within a delivery catheter or in other low-profile situations, the knitted traction portion can become blocked or locked onto the outside of the inverted support catheter during material removal. This problem is particularly pronounced when removing material from tortuous blood vessels. Therefore, there is a need for devices (including thrombectomy devices) that can remove tissue (specifically large and / or rigid materials) from within body cavities without blocking or locking. This document describes devices (devices, systems, and kits) that address the aforementioned needs and problems, as well as methods of using them. Summary of the Invention

[0010] This document describes mechanical devices (equipment, systems, etc.) and methods of using and manufacturing them. For example, a mechanical thrombectomy device is described herein. These devices can be configured to prevent or reduce blockages, especially when removing large amounts of material or hard / rigid materials. The mechanical thrombectomy device described herein includes a reversing tube (also referred to herein as a reversing traction device, traction unit, traction zone, traction section, etc.) comprising a flexible material tube that reverses itself when rolled over a distal opening of an elongated reversing support (also referred to herein as a reversing support catheter). The traction device can be a knitted tube with multiple interlocking loops (e.g., coils). The reversing support typically includes a catheter having a distal opening into which the knitted tube reverses. The flexible knitted tube reverses and rolls backward into itself and can be pulled into the elongated reversing support in a conveyor-like motion; the outward-facing region rolls nearby to become an inward-facing region, for example, within the lumen of the elongated reversing support. Therefore, the rolling motion can pull the clots or other materials inside the body cavity into the slender, reversible support, so that they can be removed from the body cavity.

[0011] In some variations, the methods and apparatus described herein address these problems and prevent the knitted tube from locking onto the outer surface of the reverse support conduit. For example, an apparatus and method for removing material from a body cavity including a knitted tube portion configured such that even when the knitted tube is held close to the outer surface of the reverse support conduit (e.g., within 1 mm, 0.8 mm, 0.5 mm, 0.4 mm, 0.2 mm, etc., on average), it does not change diameter and lock onto the outer surface of the reverse support conduit when pulled (e.g., to roll and reverse into the reverse support conduit). For example, the knitted tube may be configured to span approximately 0.5 mm above the outer surface of the conduit in an unreversed configuration. The knitted tube may be configured such that it stretches (and thus contracts) by more than a predetermined percentage when taut. For example, the knitted tube may be configured such that it elongates by no more than 3% when taut with a force of 2 Newtons. Generally, knitted tubes can be constructed to remain sufficiently flexible without stretching, allowing them to easily roll around on the distal end of the catheter, capture clots, and not get stuck inside the distal opening of the reverse support catheter.

[0012] Therefore, this document describes a specific configuration of the knitting traction device, such as the dimensions of the knitting filaments constituting the knitting tube (e.g., filament width), the number of loops per revolution of the knitting tube, and the dimensions of the reverse support guide tube above which the knitting tube is pulled (e.g., circumference). The material constituting the knitting tube (e.g., stainless steel, nickel-titanium alloy, etc.) can also contribute to the function of the device. In some variations, the dimensions of the loops (e.g., the length of the loops) can also contribute to its function. Without being bound by a specific operating principle, in the methods and devices described herein, the relationship between the number of loops per revolution, the circumference of the reverse support guide tube, and the thickness (e.g., cross-sectional thickness) of the filaments constituting the loops of the knitting tube can define a range of values ​​(as described herein) determined empirically to provide a knitting tube that resists locking onto the reverse support guide tube. Surprisingly, outside of a certain range, the knitting tube can lock onto the reverse support guide tube.

[0013] For example, this document describes an apparatus for removing material from a body cavity, comprising: an elongated reversing support including a conduit having a circumference, a distal end, and a distal opening; a knitted tube extending distally along the outer surface of the conduit in an unreversed configuration, reversing at the distal opening of the conduit, and extending proximally inside the conduit in a reversed configuration, wherein the knitted tube is configured to reverse by rolling at the distal opening of the conduit when a first end of the knitted tube is pulled proximally inside the conduit; further wherein the knitted tube is configured to elongate by less than 3% when pulled with a force of 2 Newtons in a taut state, such that the knitted tube does not lock onto the outer surface of the conduit. In any of these apparatuses, the knitted tube may be configured to be spaced (at rest) about 1 mm or less (on average) from the outer surface of the conduit in an unreversed configuration.

[0014] For example, an apparatus for removing material from a body cavity may include: an elongated reversing support comprising a conduit having a circumference, a distal end, and a distal opening; a knitted tube extending distally along the outer surface of the conduit in an unreversed configuration, reversing at the distal opening of the conduit, and extending proximally inside the conduit in a reversed configuration, wherein the knitted tube is configured to reverse by rolling at the distal opening of the conduit when the first end of the knitted tube is pulled proximally inside the conduit; further wherein the knitted tube has a length of 20 cm or greater and comprises a plurality of N loops per revolution consisting of filaments having a filament diameter, and wherein the knitted tube has a ratio of the square of the N loops per revolution to the filament diameter to the circumference of the conduit (greater than 2.9).

[0015] The number of loops per revolution of the knitting tube can be referred to as the number of stitches that make up the knitting tube, and it refers to the number of loops in the total circumference of the knitting tube.

[0016] In some variations, the knitted tube is configured to elongate by less than 2% when stretched with a force of 2 Newtons. As described above, the knitted tube can be composed of filaments knitted into a number of N loops per revolution, and wherein the knitted tube is configured, based on the number of N loops per revolution and the diameter of the filaments, to elongate by less than 3% when stretched with a force of 2 Newtons in the taut state, such that the knitted tube does not lock onto the outer surface of the catheter. In some variations, the knitted tube has a length of 20 cm or greater and comprises a number of N loops per revolution composed of filaments having a filament diameter, and wherein the ratio of the square of the N loops per revolution multiplied by the filament diameter to the circumference of the catheter is greater than 2.9. For example, the ratio of the square of the N loops per filament diameter per catheter circumference can be greater than 3.0.

[0017] In any of these devices, the knitting tube may have a length of 65 cm or greater (e.g., 70 cm or longer, 75 cm or longer, 80 cm or longer, 85 cm or longer, 90 cm or longer, 100 cm or longer, 110 cm or longer, 120 cm or longer, 130 cm or longer, 140 cm or longer, 150 cm or longer, etc.).

[0018] The filament can be a metal wire and can have any suitable filament diameter, for example, the filament diameter can be between 0.02 mm and 0.07 mm (e.g., between about 0.03 mm and 0.06 mm). In some variations, the conduit can have a circumference between 3 mm and 13 mm, for example, between 4 mm and 12 mm, etc.

[0019] Any device described herein may include a pull rod inside a conduit, wherein a first end of the knitted tube is coupled to the pull rod so that pulling the pull rod proximally can pull the knitted tube proximally inside the conduit and cause the knitted tube to roll and reverse. The elongated pull rod may be, for example, a hyaluronic acid tube having a lumen that is continuous with the knitted tube.

[0020] Generally, any of these devices can be configured such that the knitting tube is biased and expanded to a diameter greater than the inner diameter of the guide tube in the reverse configuration. The knitting tube may also, or alternatively, be biased to have an inner diameter in the non-reverse configuration that is only slightly larger than the outer diameter of the guide tube (e.g., between 0.1 mm and 3 mm, between 0.1 mm and 2 mm, between 0.1 mm and 1 mm, 1.2 mm or less, 1 mm or less, 0.8 mm or less, 0.6 mm or less, etc.).

[0021] Any of these devices may include a guide wire lumen that extends through the knitting tube and is configured to allow the guide wire to pass through.

[0022] The filament can be any suitable material. For example, the filament may contain one or more of the following materials: steel, polyester, nylon, expanded polytetrafluoroethylene (ePTFE), or nickel-titanium alloy.

[0023] Knitted tubes may include one or more coatings selected from the group consisting of lubricating coatings, metallic coatings, heparin coatings, adhesive coatings, and pharmaceutical coatings.

[0024] This document also describes methods of using any of these devices. For example, methods for removing material from inside a body cavity are described herein, including: positioning a distal end of a catheter comprising an elongated reversing support adjacent to the material; pulling a first end of a knitted tube to move the knitted tube proximally by rolling and reversing it over the distal opening of the catheter along the outer surface of the catheter in a never-reversed configuration, moving it proximally into the catheter, entering a reversing configuration inside the catheter, wherein the knitted tube is configured to elongate less than 3% when pulled with a force of 2 Newtons in a taut state such that the knitted tube does not lock onto the outer surface of the catheter; and capturing the material with the knitted tube and drawing the material into the catheter. As described above, the knitted tube may have a length of 20 cm or greater and may comprise multiple N loops per revolution of filaments having a filament diameter, and wherein the knitted tube has a ratio greater than 2.9 of the square of the circumference of each catheter N loops per revolution multiplied by the filament diameter. In some variations, pulling the first end of the knitted tube includes pulling proximally inside the catheter on a pull rod, wherein the pull rod is attached to the first end of the knitted tube.

[0025] Any of these devices may include an expandable funnel at the end of a reversing support conduit, on which a puller (in some variations, a knitted tube) is wound and reversed. The puller may have a first end coupled to the distal region of a lever (which may be an elongated wire, tube, cannula, etc.), and a flexible tube may be arranged to reverse at the funnel at the distal end of the reversing support conduit, such that as the interior (reversed) of the flexible tube moves into the funnel, the exterior of the flexible tube extends proximally along the reversing support conduit, compressing (e.g., gripped) the clot held by the flexible tube and removing fluid, and pulling the flexible tube into the reversing support conduit until the entire clot is captured, compressed, and drawn into the outer conduit. The configuration of the devices described herein is particularly suitable for gripping and removing clots (specifically large-diameter clots) using a reversing support conduit including an expandable funnel at the distal end. A collapsible / expandable funnel can be configured to operate by applying compressive force through which a flexible tube is pulled into a reversing support conduit, thereby capturing clots. The collapsible / expandable funnel can be configured to exhibit a fully expanded, latching (e.g., "squeezed") configuration when a lateral compressive force is applied to the distal face of the funnel by the flexible tube. Furthermore, the funnel may include openings (described herein as having a porous structure) through which fluid squeezed from the clot can laterally exit the funnel as it moves the clot into the narrower diameter lumen of the reversing support conduit and compresses the clot. For example, openings through the collapsible / expandable funnel (which may be referred to herein simply as an expandable funnel) that allow fluid to laterally exit the funnel wall when the clot is compressed can also prevent clot blockage or clogging.

[0026] The interior of the funnel described herein can be shaped such that material drawn into the funnel is retained within it, allowing the material to disintegrate and be compressed within the funnel without causing jamming of the auger, thus preventing pull in the auger and / or other clots. Therefore, methods and apparatus are described herein in which the distal region of the inverted support conduit is configured as a collapsible and / or expandable funnel. The expandable funnel apparatus described herein may also, or alternatively, be adapted to prevent jamming of the auger in the distal opening of the funnel, including when the apparatus is used to remove large and / or hard clots. In some variations, these funnels may be adapted to include an inner wall within the funnel that divides the funnel into multiple segments, such as small segments (e.g., 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, etc.), the proximal (narrower) end of the funnel having a steeper angle relative to the more distal end. In some variations, the funnel cavity comprises two or more chambers separated by narrowing or constriction zones. These adjustments to the funnel cavity allow harder lumps to be retained inside the funnel as the puller is drawn in and passes through the held lumps, thus aiding in the disintegration of even harder lumps.

[0027] Alternatively or additionally, in some variations, the funnel may be at least partially composed of multiple forks, arms, etc., forming the distal region of the inverted support catheter (e.g., by cutting, etc.), and the wall of the expandable funnel may be formed by a mesh cover. In this variation, the device may be adapted to prevent the forks from puncturing through the distal end of the funnel and getting caught on the traction device, thereby jamming the device. This can be achieved, for example, by forming capturing tabs at the distal end of each fork to hold the connecting filament (e.g., suture) so that it extends between the forks but cannot be displaced laterally. In some variations, the capturing tabs may be cut into tabs on the sides of the forks and bent upwards to lock the filament in place.

[0028] Therefore, generally, what is described herein is a device comprising an expandable funnel at the end of a reversing support conduit, on which a flexible tube (e.g., a traction tube or simply referred to as a puller) is wound and reversed. The flexible tube may be knitted or braided material. The flexible tube generally may have a first end connected at the distal region of a pull rod (which may be an elongated wire, tube, cannula, etc.), and the flexible tube may be arranged such that reversal occurs at the distal end of the reversing support conduit at the funnel, such that as the interior (reversed) of the flexible tube is drawn into the funnel, the exterior of the flexible tube extends proximally above the reversing support conduit, thereby compressing the clot and removing the fluid held (e.g., gripped) by the flexible tube from the clot, and pulling the reversing flexible tube into the reversing support conduit until the entire clot is captured, compressed, and drawn into the outer conduit. The configuration of the device described herein is particularly suitable for gripping and removing clots (especially large-diameter clots) by using a reversing support conduit comprising an expandable funnel at the distal end. The collapsible / expandable funnel can be configured to operate using the compressive force applied when the flexible tube is pulled into the reversing support conduit to reverse its entry into the reversing support conduit, in order to capture the clot. The collapsible / expandable funnel can be configured to present a fully expanded, locked (e.g., “clamped”) configuration when the flexible tube applies a lateral compressive force to the distal face of the funnel. Furthermore, the funnel may include openings (described herein as having a porous structure) through which fluid squeezed from the clot exits laterally from the funnel as the clot is moved into the narrower diameter lumen of the reversing support conduit and compressed. For example, openings through the collapsible / expandable funnel (which may be simply referred to herein as an expandable funnel) that allow fluid to exit laterally from the funnel wall as the clot is compressed also prevent blockage or clogging of the clot.

[0029] Any of these devices can be configured to help break down the captured material inside the funnel. For example, this document describes an apparatus for removing material from a body cavity, comprising: a reversing support including a catheter having a lumen and an elongated and flexible catheter body; an expandable funnel disposed at the distal end of the catheter body and extending along a distal-proximal axis, wherein the distal end of the funnel defines a distal opening communicating with the interior of the funnel and the lumen of the catheter, wherein, in an open configuration, the interior of the funnel has a wall angle of less than 14 degrees relative to the proximal-distal axis over a large portion of the length of the funnel, and includes a first zone (whose wall angle is between 14 and 50 degrees relative to the distal-proximal axis); and a retractor including a flexible tube extending distally along the outer surface of the catheter in an unreversed configuration, reversing at the distal opening, and extending proximally within the lumen of the catheter in a reversed configuration, wherein the flexible tube is configured to reverse by rolling over the distal opening when the first end of the retractor is pulled proximally within the lumen of the catheter.

[0030] As described above, the funnel may include a mesh forming the interior and exterior of the funnel. The funnel may include a second zone inside the funnel, wherein the wall angle relative to the distal-proximal axis is between 14 and 50 degrees, wherein the second zone is separated from the first zone by an intermediate zone, the intermediate zone having a wall angle of less than 14 degrees relative to the distal-proximal axis.

[0031] For example, an apparatus for removing material from a body cavity (e.g., removing clots from a blood vessel) may include: a reversing support comprising a catheter having a catheter lumen and an elongated and flexible catheter body, and an expandable funnel disposed at the distal end of the catheter body and extending along a distal-proximal axis, wherein the distal end of the funnel defines a distal opening communicating with the interior of the funnel and the catheter lumen, respectively, and wherein, in an open configuration, the interior of the funnel includes one or more constriction zones, wherein the interior of the funnel constricts from proximal to distal; and a retractor comprising a flexible tube extending distally along the outer surface of the catheter in an unreversed configuration, reversing above the distal opening, and extending proximally within the catheter lumen in a reversed configuration, wherein the flexible tube is configured to reverse by rolling over the distal opening when a first end of the retractor is pulled proximally within the catheter lumen.

[0032] Any of these devices may include a funnel having one or more contracting portions within its inner cavity. For example, at least a portion of the interior of a funnel having a wall angle of less than 14 degrees relative to the proximal-distal axis has a negative wall angle relative to the distal-proximal axis, such that the interior of the funnel contracts in the proximal-distal direction. Generally, the wall angle inside the funnel is measured between the proximal-distal axis and the wall inside the funnel in the distal direction.

[0033] Generally, the exterior of a funnel may have a wall profile that differs from the interior wall profile. For example, in some variations, the entire exterior of the funnel has a wall angle of less than 14 degrees relative to the proximal-distal axis (in the direction facing distally).

[0034] Any funnel described herein may include an opening that allows the passage of fluid from a material being compressed when it is drawn into the funnel. For example, at least a basal region (base region) of the funnel adjacent to the distal end of the conduit body may include an opening configured to allow fluid to pass through it. In some variations, the funnel includes a circumferentially porous region at the base of the funnel adjacent to the distal end of the conduit body, the porous region being configured to allow fluid to pass through it.

[0035] The funnel may have a converging configuration, wherein the maximum outer diameter of the converging configuration is less than 0.3 times the outer diameter of the catheter body near the proximal side of the funnel. The funnel may also have an open (e.g., expanding) configuration, wherein the minimum outer diameter of the funnel is greater than 1.5 times the outer diameter of the catheter body near the proximal side of the funnel.

[0036] The funnel can be any suitable size for insertion into a body cavity and for opening inside an internal lumen (e.g., a blood vessel). For example, in an open configuration, the funnel can have an outer diameter between 2 and 26 mm.

[0037] As mentioned above, in any of these variations, the flexible tube may include a knitted tube.

[0038] The funnel can be configured to open from a closed (e.g., unexpanded) configuration into an open configuration when the flexible tube is pulled proximally into the lumen of the catheter and an axial compressive force is applied to the distal end of the funnel.

[0039] In any of these devices and methods, the funnel can be held in a jammed state (in the open configuration) when the flexible tube is pulled proximally into the lumen of the catheter. Therefore, by pulling the traction device into the distal opening of the funnel, the funnel can be opened and locked (jammed) in a high-column-strength jammed state. The funnel in the jammed state can have greater column strength compared to an unopened funnel and / or a funnel in the unjammed state. For example, the funnel can be configured to withstand compressive forces greater than 5 Newtons (e.g., 7 Newtons or more, 8 Newtons or more, 10 Newtons or more, 11 Newtons or more, 12 Newtons or more, 13 Newtons or more, 14 Newtons or more, 15 Newtons or more, 18 Newtons or more, 20 Newtons or more, etc.) without collapsing in the jammed state.

[0040] In any of these devices, the funnel may include a plurality of longitudinal branches (tines) continuous with the catheter body proximal to the funnel. Alternatively or additionally, the funnel may include a mesh reversed over itself, forming an inner and outer wall of the funnel, with the plurality of longitudinal branches located between the inner and outer walls of the funnel. In some variations, the device (e.g., the funnel) may include filaments connecting the ends of the branches; these filaments may be locked at the distal end of the branches to prevent the branches from protruding through the covering mesh (e.g., a knitted or woven mesh) during operation of the device, the branches hooking onto the retractor when it is pulled into the distal opening.

[0041] As described above, any of these devices may include a pull rod disposed inside the lumen of the catheter, wherein a first end of the traction device is connected to the pull rod.

[0042] This document also describes a method for removing material from a body cavity, comprising: advancing a reversing traction device through the body cavity until the distal end of the device is located near the material, wherein the reversing traction device includes a reversing support (which includes a catheter having a catheter body and an inner catheter lumen) and an expandable funnel disposed at the distal end of the catheter body and extending along a distal-proximal axis, wherein the distal end of the funnel defines a distal opening communicating with the interior of the funnel and the inner catheter lumen, respectively; the reversing traction device further includes a traction device including a flexible tube extending distally along the outer surface of the catheter in an unreversed configuration. The process involves: pulling the first end of a retractor proximally within the catheter lumen, causing the retractor to reverse above the distal opening; applying axial compression to the distal end of the funnel proximally and opening it from a closed to an open state; and pulling material into a first distal region of the funnel, having a wall angle of less than 14 degrees relative to the proximal-distal axis of the funnel, followed by pulling the material into a second, more proximal region of the funnel, having a wall angle between 14 and 50 degrees relative to the distal-proximal axis, thereby compressing and forcing the material into the catheter lumen. Any of these methods can be used to remove blood clots (thrombi) from a blood vessel.

[0043] For example, a method for removing material from a body cavity may include: advancing a reversing traction device through the body cavity until the distal end of the device is located near the material, wherein the reversing traction device includes a reversing support (which includes a catheter having a catheter body and a catheter lumen) and an expandable funnel disposed at the distal end of the catheter body and extending in a distal-proximal axis, wherein the distal end of the funnel defines a distal opening communicating with the interior of the funnel and the catheter lumen, respectively, and the reversing traction device also includes a tractioner comprising, in an unreversed configuration, a tractioner facing along the outer surface of the catheter. A distally extending flexible tube; a first end of a retractor is pulled proximally within the lumen of the catheter, causing the retractor to reverse above the distal opening, wherein the first end of the retractor is pulled proximally, applying an axial compressive force to the distal end of the funnel and causing the funnel to open from a closed state to an open state; and material is pulled into a first distal region within the funnel, and then into a second more proximal region within the funnel, wherein the first and second regions are separated by a contraction that narrows the inner diameter of the funnel, thereby compressing and squeezing the material into the lumen of the catheter.

[0044] In any of these methods and devices, the elongated reversing support portion of the device described herein can be or may include (specifically at its distal end) any suitable catheter, such as a flexible tube that can be inserted into a body vasculature (e.g., a blood vessel), into which a more flexible traction portion of the elongated reversing support can be aspirated. In some variations, the elongated reversing support may also be referred to as an external catheter (e.g., when the lever for the retractor is referred to as an internal catheter) and / or a reversing catheter and / or a supporting catheter, as it supports the reversal of the retractor. The elongated reversing support (which includes the catheter constituting the elongated reversing support) may include braided or woven portions, spiral or coiled portions, etc. (e.g., having a braided shaft), may have a single layer or multiple layers, and may be made of biocompatible materials, including polymers, metals, etc. (e.g., polytetrafluoroethylene (PTFE)). Examples of vascular catheters that can constitute the elongated reversing support include microcatheters.

[0045] As described above, the device described herein can be a mechanical thrombectomy device and may include a traction unit and / or an elongated reversing support configured to prevent locking onto the outside of the reversing support while still being able to efficiently "grab" the clot from inside the body cavity. For example, the mechanical thrombectomy device described herein may be configured to grasp or hold the clot and / or soften the clot to remove it when it is mechanically aspirated into the device. Although aspiration may be applied in addition to mechanical grasping of the clot, it is not used in some variations.

[0046] The traction zone described herein may include protrusions that extend specifically or exclusively from the traction zone when it bends in the vicinity (e.g., at the distal end of the device) during reversal. These protrusions may remain straight or non-extended when the traction device is held parallel to the elongated reversal support. Alternatively, the protrusions may always extend. Generally, the traction device may be constructed of a braided material, a knitted material, or a laser-cut sheet of material. Knitted and / or braided materials may be fibrous materials (including natural fibers, synthetic fibers, etc.), polymeric materials, etc. For example, the material constituting the braided or knitted material (e.g., strands) may be one or more of the following: monofilament polymers, multifilament polymers, NiTi filaments, NiTi tubes with a radiopaque metal center, cobalt-chromium alloy filaments, cobalt-chromium alloy tubes with a radiopaque metal center, nylon, polyester, polyethylene terephthalate, and polypropylene. The sheet of material being shaped into the traction zone (e.g., a solid sheet of material) can be one or more of the following: polymeric materials (e.g., PTFE), silicone materials, polyurethanes, shape memory alloys, stainless steel, etc. These sheets can be extruded, glued, etc. These sheets can be cut to form holes and / or protrusions. For example, these sheets may include one or more laser-cut protrusions. Any of these devices can be coated with a hydrophilic and / or hydrophobic coating and / or may include holes. The traction device may have a porosity greater than >60% (greater than 70%, greater than 75%, greater than 80%, greater than 85%, etc., between 60-95%, 65-95%, 70-95%, etc.).

[0047] For example, this document describes a clot-grabbing mechanical thrombectomy device that includes a traction zone. The traction zone may include a plurality of clot-grabbing protrusions extending from one face of the traction device. In some variations, the clot-grabbing protrusions may be configured such that when the traction zone bends, for example, around the distal end of a catheter of an elongated reversing support, they move and extend (e.g., from the plane of the traction device) in reverse.

[0048] The traction device can be configured (e.g., by heat setting, shape setting, etc.) to hold this portion of the traction device inside the catheter in an inverted configuration such that it is close to the inner diameter of the catheter; for example, the inner diameter of the portion of the traction device inside the catheter can be greater than 50%, greater than 55%, greater than 60%, greater than 65%, greater than 70%, greater than 75%, etc. of the inner diameter of the catheter.

[0049] Furthermore, in any of the devices described herein, the traction device in the non-reverse configuration maintains an outer diameter slightly larger than the outer diameter of the reverse support catheter. The traction device may be biased to keep its outer diameter (OD) within approximately 2 mm, approximately 1.5 mm, approximately 1 mm, approximately 0.8 mm, approximately 0.7 mm, approximately 0.6 mm, and approximately 0.5 mm of the outer diameter (OD) of the reverse support catheter.

[0050] Any device described herein may include a traction device having one or more coatings selected from the group consisting of lubricating coatings, metallic coatings, heparin coatings, adhesive coatings, and pharmaceutical coatings. Attached Figure Description

[0051] A better understanding of the features and advantages of the disclosed apparatus and methods of using them will be obtained by referring to the following detailed description, when read in conjunction with the accompanying drawings, wherein:

[0052] Figures 1A-1D The illustration shows an example of a device for mechanically removing objects (such as clots) from a body area. Figure 1A An example of a device including an elongated reversing support (including a conduit) is shown. For example, at least the distal end of the elongated reversing support may be configured as a conduit. The device also includes a flexible tube configured as a traction device that can be pulled into the lumen of the reversing support. Figure 1B This illustrates a location within an interior lumen (e.g., a blood vessel) and adjacent to the material to be removed (e.g., a clot). Figure 1A The device. Figure 1C It shows being actuated to remove material Figure 1A Device. Figure 1D As shown Figures 1A-1C One possible failure mode of the device shown is that a traction device, which may be configured to exist near the outer surface of the reversing support (in the relaxed configuration), can be suppressed onto the reversing support, thereby preventing the operation of the device.

[0053] Figures 2A-2B The illustrations separately depict a traction device made of knitted material, such as... Figures 1A-1D The end perspective view and side view of the device shown are illustrated in the figure.

[0054] Figure 3A The illustration depicts an example of a tortuous anatomical region shown as an Ilioa-Caval arc through which a device (e.g., a reversing tube device) as described herein is guided.

[0055] Figure 3B An example of a prototype device including a cuff that surrounds a portion of the distal region of a traction device on the outside of a reversing support is shown.

[0056] Figure 4A An enlarged view of an example of a knitted traction zone is shown, illustrating a loop that is typically teardrop-shaped.

[0057] Figure 4B and Figure 4C Examples of knitting traction devices with 22 needles (e.g., 22 loops per revolution) and 34 needles (e.g., 34 loops per revolution) are shown.

[0058] Figure 5 Table 1 illustrates examples of traction devices with different parameters examined based on the force applied before the device is locked onto the outer diameter of the reverse support conduit. The different parameters illustrated in this table include the number of loops per revolution, the size of the conduit on which the traction device is used, the thickness of the filament (“wire”) used to form the knitted traction device, and the locking force used to lock the traction device onto the reverse support conduit. In these experiments, longer traction devices (e.g., formed from knitted filaments with the indicated thickness and number of loops) formed in the manner described in the figure were examined by pulling the traction device onto a reverse support conduit of the indicated size until the traction device was locked onto the reverse support conduit.

[0059] Figure 6 Similar to those in large blood vessels Figure 1A One example of the reversing tube device shown has a clot with a diameter greater than twice the inner diameter of the reversing support conduit. Although the clot can be taken in and removed by a reversing tube device with a narrower diameter reversing support conduit, the reversal efficiency is low, especially when the clot is made of a hard (e.g., partially calcified) material.

[0060] Figures 7A-7B An example of a reversing tube device as described herein is shown, which is suitable for dehydrating (e.g., removing liquid) a material (e.g., agglomerate) upon ingestion to improve reversing efficiency, wherein the funnel includes inner zones with different wall angles that help break up and compress harder agglomerates. Figure 7A The image shows the reversing tube device in an unplaced state inside an intermediate (e.g., delivery) conduit; the reversing support conduit includes an expandable funnel at the distal end of a flexible tube that reverses thereon. The flexible tube is attached to the distal region of the pull rod, allowing the pull rod to extend distally. Figure 7B In the middle, it is displayed Figure 7A The reversing tube device is in a placed state, with at least the distal end extending from the intermediate conduit; the expandable funnel at the distal end of the reversing support conduit is in an open configuration.

[0061] Figures 8A-8B The illustration shows another example of a reversible tube device comprising an expandable funnel with different inner wall angles, wherein a flexible tube (e.g., a knitted tube) is attached to the distal end of a pull rod. Figure 8B The placement configuration is shown. Figure 8A A reversing tube device in which an intermediate (e.g., delivery) conduit is retracted proximally so that an expandable funnel at the distal end of the reversing support conduit can expand, and a flexible tube can expand.

[0062] Figure 8C It is similar to Figures 8A-8C An image of a prototype of the inverting tube device shown.

[0063] Figures 9A-9B An example of a reversing tube device is shown, which includes a funnel at the distal end of a reversing support conduit over which a knitted flexible tube is rolled up and reversed. Figure 9A It is a top-down perspective view and Figure 9B It is a side view.

[0064] Figures 10A-10C The illustration shows an example of an inverted support conduit with an expandable funnel at its distal end.

[0065] Figure 11A Figure 11D illustrates an example of a reverse support conduit with an expandable funnel. Figure 11A This is a schematic diagram of a reversing support conduit including a funnel, the funnel comprising a support frame formed by the distal region of an elongated reversing support conduit. Figure 11B It shows that it was cut and formed in Figure 11A An example of a reverse support conduit for a support member is shown schematically. Figure 11C It is attached to the frame (such as Figure 11B An example of a distal funnel of a reverse support conduit made of woven material (as shown in the frame). Figure 11D yes Figure 11C The end view of the funnel shown.

[0066] Figure 12 This is an example of a funnel constructed as a reverse-support conduit with axial compressive strength sufficient to prevent folding when an axial compressive force greater than 500g (e.g., greater than 1kg, greater than 1.2kg, greater than 1.5kg, etc.) is applied. In this example, the axial compressive force applied by a flexible tube that is pulled proximally (e.g., pulled) and rolled over the distal end of the funnel can also open the funnel to accommodate it.

[0067] Figure 13 This is an example of an expandable funnel of a reverse-supported conduit in a relaxed state. Figure 14 This is another example of an expandable funnel with reverse support conduit.

[0068] Figure 15AThis is an example of the distal end of a reversing support member, including an expandable distal funnel, illustrated in an expanded state. In this embodiment, the funnel includes small (e.g., less than 14 degrees) wall angles on both the outer and inner walls.

[0069] Figure 15B Another example is shown, illustrated in an expanded state, of the distal end of a reversing support including an expandable distal funnel.

[0070] Figures 16A-16D The illustration shows an example of a schematic cross-section through the distal end of a reversing support including an expandable distal funnel, showing the internal cavity region at different wall angles. Figure 16A The cavity includes a first zone with a wall angle of approximately 10 degrees (maximum) and a second zone with a wall angle of approximately 14 degrees (maximum). Figure 16B The cavity is shown to include a first zone with a wall angle of approximately 10 degrees (maximum) and a second zone with a wall angle of approximately 30 degrees (maximum). Figure 16C The cavity is shown to include a first zone with a wall angle of approximately 7 degrees (maximum) and a second zone with a wall angle of approximately 50 degrees (maximum). Figure 16D An example of the inner cavity of a funnel with three different wall angles is shown, the inner cavity including a first zone with a wall angle of 10 degrees or less, a second zone with a wall angle of 14 degrees (e.g., between 14 and 50 degrees), and a third zone with a wall angle of 10 degrees or less.

[0071] Figure 17 Another example of a prototype of a reversing support is shown, which includes a distal end of a funnel configured to have one or more contraction zones inside an inner cavity (which helps trap hard materials).

[0072] Figures 18A-18B The diagram illustrates a process similar to Figure 17 An example of the cross-section of the funnel of the inverted support shown (which has two contraction zones).

[0073] Figure 19 It is an example of a prototype funnel, in which the branch supporting the funnel protrudes beyond the distal covering that constitutes the outer surface of the funnel.

[0074] Figures 20A-20B An example of a set of forks is shown, which forms a funnel of inverted support including bridging elements (illustrated in this example as sutures (constraint filaments)).

[0075] Figures 21A-21D The illustration shows the formation of a global proximal constraint for the constraint filament formed by the bifurcation of the funnel.

[0076] Figures 22A-22BSide and end perspective views of a bifurcation, including a proximal constraint integrally formed by the bifurcation, as described herein, are shown respectively. This bifurcation may be part of a funnel. Detailed Implementation

[0077] Generally, this document describes devices with a reversing traction device configured to roll (retract) into a reversing support catheter and capture material from within the blood vessel. Specifically, this document describes methods and devices configured to capture material using a reversing traction device, wherein the traction device is a knitted traction device configured to prevent locking on the lateral side of a reversing support (e.g., a reversing support catheter). This document also describes devices in which the reversing support catheter includes an expandable funnel at its distal end having an inner profile adapted to capture and break up hard material captured by the traction device so that it can be pulled into the reversing support catheter for removal.

[0078] For example, these devices may include knitted retractors configured such that even longer retractors (e.g., greater than 20 cm) adhering to the outer side of the reverse support member (e.g., within 2 mm of the outer diameter of the reverse support catheter) when pulled into the reverse support catheter at the distal opening will not lock onto the outer side of the reverse support member. The retractor may have a knitted tube configured to elongate by less than 3% when pulled with a force of 2 Newtons in a taut state. For example, in some variations, the retractor may include a braided device consisting of several N loops per revolution made of filaments having a filament diameter, wherein the ratio of the square of the circumference of each catheter multiplied by the N loops per revolution to the filament diameter is greater than 2.9 (e.g., greater than 3.0, etc.). The range of fabric sizes and the number of loops per revolution can be selected in a manner described herein to prevent elongation of longer retractors while maintaining the flexibility of the retractor and its ability to capture material from the blood vessel without increasing the force required to pull the retractor into the reverse support catheter.

[0079] The devices described herein are generally configured to include a fabric retractor designed to prevent entrapment (including locking onto a reversing support catheter). The devices described herein typically include an elongated reversing support with a supporting ring, the retractor being reversed distally above the ring. The retractor may include a flexible (e.g., knitted) tube that is folded backward (e.g., reversed) at the distal end of the elongated reversing support (e.g., catheter) such that it extends into the annular opening of the elongated reversing support. In some variations, an inner pull rod may be coupled to one end of the retractor so that the retractor can be pulled proximally to reverse above the distal opening (ring) of the elongated reversing support to coil and capture material within the blood vessel. The device may include a guidewire lumen extending through the elongated reversing support and / or a retraction rod configured to allow the guidewire to pass through.

[0080] The methods and apparatus described herein prevent knitted tubes from locking onto the outer surface of a reverse support catheter. For example, the apparatus and method described herein are for removing material from a blood vessel including a traction unit configured such that even when the traction tube is held close to the outer surface of the reverse support catheter (e.g., within 1.5 mm, 1 mm, 0.8 mm, 0.5 mm, 0.4 mm, 0.2 mm, etc., on average in some variations), even longer lengths of knitted tubes will not become stuck and locked onto the outer surface of the reverse support catheter when pulled into it. For example, the traction unit may be configured such that when pulled in a taut state, it elongates (and therefore contracts) by no more than a predetermined percentage. The traction unit may be configured such that when pulled in a taut state with a force of 2 Newtons, it elongates by no more than 3%. Generally, the puller can be configured to not elongate while still maintaining sufficient flexibility to easily roll over and capture clots on the distal end of the catheter without getting stuck in the distal opening of the reverse support catheter.

[0081] Therefore, this document describes specific configurations of a knitting puller, such as the dimensions of the knitting filaments constituting the puller (e.g., filament width), the number of loops per revolution of the knitting puller, and the dimensions (e.g., circumference) of the reverse support guide tube above which the puller tube is pulled. The materials constituting the knitting puller (e.g., stainless steel, nickel-titanium alloy, etc.) can also contribute to device performance, as the dimensions of the loops (e.g., length) can also contribute to performance. Without being constrained by a specific operating principle, this document describes methods and apparatuses in which the relationship between the number of loops per revolution of the knitting puller, the circumference of the reverse support guide tube, and the thickness of the filaments constituting the loops (e.g., cross-sectional thickness) can define a series of values ​​(as described herein) that have been empirically discovered to provide a knitting puller that resists locking onto the reverse support guide tube. Surprisingly, outside of these defined ranges, the knitting tube locks onto the reverse support guide tube.

[0082] Any device described herein may also include coatings (e.g., hydrophilic, lubricating coatings, etc.) to enhance the sliding and reversing of the retractor over the distal end. Furthermore, any of these devices may include one or more protrusions configured to enhance clot gripping and / or softening. Clot gripping can be particularly useful, but not exclusively, when the retractor is smooth. While a smooth retractor prevents jamming and requires less force to operate (e.g., reversing over the distal end of a catheter), it is more difficult to initially grip or hold the clot when the retractor is smoother. Also particularly useful are protrusions that are retracted along the length of the retractor adjacent to an elongated reversing support (e.g., a catheter), for example, when the device is positioned inside the blood vessel, but extend outward from the retractor when rolled and reversed to grip the clot.

[0083] Generally, a device for removing material from a blood vessel can be a system, component, or apparatus that includes an elongated reversing support having distal and distal rings, and a flexible traction assembly that is at least partially reversed and configured to roll and reverse over the distal ring of the elongated reversing support.

[0084] In many of the examples described herein, the elongated reversing support is a catheter (or a portion of the catheter at its distal end) and the loop is formed by the distal opening of the catheter; the retractor extends inside the catheter and above the distal end of the catheter, extending posteriorly over the outer diameter of the catheter, although it may extend proximally to any suitable distance (including greater than 20 cm, e.g., greater than 30 cm, between 20 and 200 cm, greater than 40 cm, 50 cm, 60 cm, 70 cm, 80 cm, 90 cm, 100 cm, 110 cm, 120 cm, 130 cm, 140 cm, 150 cm, 160 cm, 170 cm, 180 cm, 200 cm, etc.). The end of the retractor inside the catheter may be coupled to a lever (e.g., in the region closest to the distal or inner end of the retractor). The tubular retractor and lever may include an elongated lumen configured to allow the guidewire to pass through. A tubular retractor can also cause the catheter to slide and reverse along its long axis inside the catheter lumen above the distal opening when the proximal region is pulled proximally. In this text, the retractor may be referred to as the retractor assembly, traction section, retractor tube, or simply the retractor, and is typically located inside the catheter and can slide longitudinally within the catheter, and is arranged such that a portion of the retractor (sometimes referred to as the “distal retractor zone” or “distal-facing” retractor zone) folds backward on itself.

[0085] For example, Figure 1AA variation of the device 100 is shown, which includes a conduit with an elongated inverted support. In this example, the elongated inverted support includes a conduit 107 having a distal region 113 including a distal opening 115. This distal region may have a gradually increasing softness (measured with a hardness tester, such as a Shore hardness tester), except that the softness of the extremely distal region (distal 115, including the distal opening) decreases significantly compared to the region immediately adjacent to it. Therefore, although the distal tip region of the catheter (e.g., the distal x-linear dimension, where x is 10cm, 7cm, 5cm, 4cm, 3cm, 2cm, 1cm, 9mm, 8mm, 7mm, 6mm, 5mm, 4mm, 3mm) has increased softness / decreased hardness as it extends from the proximal to the distal end, the extremely distal region (e.g., measured as the distal z-linear dimension, where z is 1cm, 9mm, 8mm, 7mm, 6mm, 5mm, 4mm, 3mm, 2mm, 1mm, 0.8mm, 0.5mm, 0.3mm, 0.2mm, etc., and z is always at least three times smaller than x) is harder than the proximal region immediately adjacent to it, and can be as hard as or harder than the nearest region of the distal tip region.

[0086] exist Figure 1A In this context, the elongated reversing support is an elongated hollow catheter with sufficient column strength to prevent buckling when the catheter is pulled on the distal annulus (distal opening). Therefore, for neurovascular applications, the elongated reversing support can be configured such that it does not fold (e.g., bend) when a compressive force of 500g or less (e.g., at least about 700g, 600g, 500g, 400g, 300g, etc.) is applied. For peripheral vascular applications, the elongated reversing support can be selectively or configured to withstand a compressive force of at least 1500g (e.g., at least about 200g, 1900g, 1800g, 1700g, 1600g, 1500g, 1400g, etc.). Generally, any device described herein may include an elongated reversing support that is not a full-length catheter but may include a portion of the catheter, typically connected distally to a rod, wire, hypotube, etc., or may be cut. In some variations, the distal end 115 of the elongated reversing support is modified so that the puller 103 can slide or roll and reverse over the distal end of the catheter without being captured (bound, stuck) or with significant friction.

[0087] Figure 1AThe illustrated device also includes a pull rod 101 connected at or near its distal end to a retractor 103. In some variations, the retractor may be attached to a slightly proximal region of the pull rod such that the distal end of the pull rod extends forward in front of the pull rod as it extends distally from the reversing support conduit. Thus, the retractor can be wound over the distal opening 111 of the reversing support conduit. In this example, the retractor 103 is configured to span over the outer diameter of the reversing support member so that it is within, for example, about 1 mm or less (e.g., 0.5 mm or less) of the outer diameter of the reversing support conduit.

[0088] Figure 1B This illustrates the interior of a body lumen (e.g., a blood vessel) where the clot 109 is located. Figure 1A The device. The proximal end of the device may be located adjacent to the clot. In some variations, the delivery catheter (not shown) may be located inside the blood vessel and the inverted support catheter and retractor (and in some variations, a pull rod) may be driven, for example above the guidewire, through the delivery catheter so that it is adjacent to the clot. Figure 1C An example of a flexible traction device 103 coupled to a pull rod 101 is shown. In this example, the traction device 103 is integrated with the pull rod 101, thus forming an assembly. Figure 1C In this design, the traction device is a tube of a flexible and elongated (longer than 20 cm) material (e.g., knitted). The traction device has a relaxed inner diameter, which is slightly larger than the outer diameter of the conduit into which the traction device will be pulled. The flexible and tubular traction device 103 can be sufficiently soft and flexible (e.g., with low folding strength) to be easily rolled and folded over the distal hole of the elongated reverse support. The pull rod 101 can be, for example, a thiocyanate tube. In some variations, the pull rod is not necessary, and the inner end of the traction device can extend proximally and be pulled directly.

[0089] exist Figure 1C In this configuration, the traction device 103 is provided, for example, by shaping (heat shaping, etc.) in a relaxed inverted configuration (when inverted inside the inverted support conduit) and expands to a radial diameter that, when unconstrained, is at least 60% of the inner diameter of the inverted support conduit (e.g., at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, etc., for example between 0.7 and 4 times, between 0.8 and 4 times, between 0.7 and 2 times, etc.). This prevents the inverted traction device from collapsing onto itself in the inverted configuration, even when pulled proximally into the conduit. This can also be used for an outwardly flared shape when it is inverted into the distal opening of the conduit.

[0090] Figure 1C It shows Figures 1A-1BThe device is operated to draw clotted material into a reverse support conduit. In this example, the pull rod 101 is pulled proximally (arrow 135) while the reverse support conduit is held steady or traveled distally; thereby pulling the knitting traction device 103 at (along the distal opening of the reverse support conduit) causes it to wind 113 and reverse into the reverse support conduit, thereby drawing clotted material.

[0091] Generally, longer traction devices have been found, specifically longer knitting traction devices (such as those longer than approximately 20 cm (e.g., approximately 25 cm or longer, approximately 30 cm or longer, approximately 35 cm or longer, approximately 40 cm or longer, approximately 45 cm or longer, approximately 50 cm or longer, approximately 60 cm or longer, approximately 70 cm or longer, approximately 80 cm or longer, approximately 100 cm or longer, approximately 110 cm or longer, approximately 140 cm or longer, approximately 150 cm or longer, etc.). These knitting traction devices can lock due to friction between the traction device and the outside of the reverse support tube, as in... Figure 1D As shown. In Figure 1D In the image, arrow 160 shows the traction device stuck downwards onto the outside of the reversing support conduit 107. This is particularly problematic when the inner diameter of the traction device in the relaxation configuration is within a few centimeters of the outer diameter of the reversing support conduit (e.g., within about 2 mm, within about 1.5 mm, within about 1 mm, within about 0.8 mm, etc.). Figures 2A-2B The illustration shows an example of a knitting traction device 203 extending on the outside of a reverse support conduit 207.

[0092] For various reasons, the retractor can lock onto the lateral side of the reverse-support catheter. For example, in some variations, the retractor (specifically, a knitted retractor) experiences increased friction on the lateral side of the catheter when navigating tortuous areas of the vessel. For example, as... Figure 3A As shown, when passing through the Ilioa-Caval arc 344, this causes the diameter of the reverse support conduit to become elliptical, which can lead to clamping of the traction device in this area. In some variations, the end of the traction device may include a cuff 330, as... Figure 3A As shown, this problem can arise when it adheres to the outer diameter of the catheter, such as Figure 3B As shown in the diagram. These problems can be partially mitigated by lubricating the cuff area (or using a smooth material) and / or by widening the sleeve or avoiding areas with high curvature. However, a more general solution is also described in this paper.

[0093] Specifically, this paper describes a traction device in which the knitting tube is configured to reduce elongation under tension. For example, the traction device described herein has been shown to reduce or prevent downward locking to the outside of the reverse support tube when the knitting traction device is configured to reduce elongation by less than 3% when pulled with a force of 2 Newtons under tension (e.g., configured to reduce elongation by less than 2% when pulled with a force of 2 Newtons under tension). Although the knitting traction device (as in...) Figures 2A-2B (As shown) is typically highly stretchable because the connection is usually an interlocking oval or circular connection made of filaments from stainless steel, nickel-titanium alloy, or polymer materials. The percentage of stretch can be limited by controlling the number of loops per revolution (e.g., one circumference of the knitted traction device) and the filament diameter relative to the circumference of the reverse support conduit. For example, a knitted tube made of filaments knitted into N loops per revolution can be constructed based on the number of N loops per revolution and the diameter of the filaments to stretch less than 3% when pulled with a force of 2 Newtons in the tensioned state. Other factors (such as the length of the loops and the filament material) also play a role, but the number of loops and the cross-sectional diameter of the filaments have the greatest effect on the stretching and thus on the stretching of the traction device in the tensioned state, thereby preventing the traction device from locking onto the outside of the reverse support conduit.

[0094] It should be noted that other methods may exist to modify and / or reduce the stretch of the knitting traction device, including stiffening the traction device (e.g., by adding or incorporating material such as a sleeve into the traction device). However, stiffening the traction device is disadvantageous, and particularly detrimental to the ability of the traction device to be easily reversed at the distal opening of the reverse support conduit.

[0095] Generally, any of the devices described herein can also be configured such that they are biased (e.g., shape-setting, heat-setting, etc.) to prevent a significant reduction in the inner diameter of the traction device in the unreversed configuration when pulled in a taut state. Furthermore, any of these devices may contain a smooth material between the outer surface of the reversing support conduit and the traction device. While such adjustment would be advantageous, it has been found that limiting elongation per revolution by adjusting the number of filaments per revolution, for example, based at least in part on the filament diameter and the outer circumference of the conduit, optimally allows for highly flexible, low-friction movement of the traction device while optimally capturing material in the knitting device.

[0096] As shown in Figure 4, the knitting traction device may include teardrop-shaped loops, each loop having a length of 400 and a width of 406. The ratio of the length to the width of each loop may be greater than 6 (e.g., the length may be more than six times the width), or in some variations greater than 7 times the length (e.g., greater than 8 times, 9 times, 10 times, etc.).

[0097] Generally, the diameter and stiffness of the filaments can be controlled to prevent stretching. For example, the larger the wire diameter, the better the knitted retractor resists locking onto the outside of the catheter. However, larger diameter filaments can increase the stiffness of the retractor, which can pose a risk of damaging the blood vessel, especially when reversing the retractor into the catheter. Greater stiffness also increases the force required to reverse the retractor, which is also undesirable.

[0098] In some variations of inverted catheter devices (e.g., thrombectomy devices), the knitted traction device can be shaped to have an inner diameter much larger than the outer diameter of the inverted support catheter. See, for example, U.S. Patent Application Publication No. 2019 / 0336148. However, in some variations, it is preferable that the knitted traction device has an inner diameter closer to the outer diameter of the catheter, especially where a narrower profile device is required. These devices can also have lower pulling friction (e.g., requiring lower tension) due to reduced friction within the catheter.

[0099] The number of loops per revolution of the traction device can be controlled, for example, by increasing or decreasing the number of needles used to form the knitting traction device tube. For example, Figure 4B The illustration shows an example of a traction tube formed with 22 needles per revolution (e.g., with 22 loops per revolution), while Figure 4C An example is shown of the same filament formed with the same inner diameter having 34 needles per revolution (e.g., 34 loops per revolution). In this example, the filament is a 0.0012-inch (e.g., 0.03048 mm) diameter nickel-titanium alloy wire, configured for use on a 5French reverse support catheter (e.g., for insertion into the body via a 6F tube), and the relaxation inner diameter of the traction tube may differ from the outer diameter of the reverse support catheter by less than about 1 mm.

[0100] Various factors (including filament material, filament diameter, number of loops per revolution, loop length, filament material, and circumference of the reversing support catheter) vary in several longer (e.g., greater than 20 cm) pullers and are examined to determine the locking force (e.g., the amount of force applied in the taut state) required to lock the puller onto the outer diameter of various sizes of reversing support catheters. When stationary, the puller can be assumed to be within 1.5 mm of the outer diameter of the reversing support catheter. Other criteria include the general force required to pull (and reverse) the device.

[0101] Figure 5 Table 1 shows some of these results, upon which multiparameter analysis was performed. Figure 5 The diagram shows the number of turns per revolution for various wire thicknesses (in both inches and millimeters) and various inverted support conduit outer diameters (shown in French units and inverted support circumference). Figure 5The data shown are for nickel-titanium alloy filaments. Similar results were found for other filament materials (e.g., stainless steel, polyester, nylon, expanded polytetrafluoroethylene (ePTFE)). For these various embodiments, the locking force was assessed quantitatively (in grams) or qualitatively (a is acceptable, or u is unacceptable).

[0102] Surprisingly, the number of loops was identified as the key variable, as was the diameter of the knitted wire. Less important were the loop size (e.g., the length-to-diameter ratio) and the wire material. For some of these examples, besides... Figure 5 In addition to the data shown, the percentage of elongation was measured when a force of 2 Newtons was applied during tension (as a standard), and this result was used to determine the minimum amount of elongation produced by the knitted tube to prevent or minimize the puller from locking onto the outside of the conduit (reverse support conduit) when the puller tube is long (e.g., 20 cm or longer), where the inner diameter of the puller is close to (e.g., within 2 mm, 1.5 mm, 1 mm, etc.) the outer diameter of the reverse support conduit. Specifically, in most cases, elongation of less than 3% when pulled with a force of 2 N in the tensioned state avoids locking of pullers longer than 20 cm, while still allowing the puller to remain sufficiently flexible. This majority can be increased, for example, to 2.9%, without making the puller excessively stiff.

[0103] In some cases, the elongation profile of the knitting traction device can therefore depend on the factors mentioned above (e.g., the number of loops per revolution, the circumference of the reverse support tube on which the traction device is used, the diameter of the filaments forming the loops, etc.). Figure 5 As shown, the relationship between the number of loops per revolution, the circumference of the support conduit (and thus the circumference of the traction tube configured to tightly span the reverse support conduit), and the thickness of the filament braided into the loop was confirmed, and a threshold was determined. Empirically, the square of the number of loops per revolution multiplied by the diameter of the filament, divided by the circumference of the reverse support conduit, provides a dimensionless quantity that can be used to determine whether a particular traction device is suitable for a relatively long (e.g., 20 cm or longer) device in which the knitted traction device tightly spans the reverse support conduit in a relaxed state.

[0104] like Figure 5 As shown, this cutoff value is approximately 2.9 (e.g., greater than 2.9, greater than 3.0, etc.). For these same devices, the ratio of ring length to ring width can be 6 or greater (e.g., 7 or greater, 8 or greater, 9 or greater, etc.). Below this cutoff value, the locking force would be too low to allow the device to be used, and it would jam against the outer surface of the catheter and prevent it from slipping.

[0105] Therefore, the relationship that can be called the choke ratio is:

[0106] Restriction ratio = N2 ×D 长丝 / C 导管

[0107] Where N is the number of rings / revolution of the traction device, and D... 长丝 It is the diameter of the filament (e.g., metal wire) that makes up the ring, and C 导管 It is the circumference of the reverse support catheter on which the traction device is used.

[0108] The drag ratio is a dimensionless value and can be rearranged to provide various loop / turn counts for specific filaments and reverse support guides. For example, this drag ratio can be used to solve for the minimum number of loops / turns in a device where the traction device tightly spans the reverse support guide and is composed of filaments with a specific diameter. Surprisingly, this relationship shows that increasing the number of loops / turns increases the resistance of the knitting traction device to collapse (shrinkage) and lock onto the guide OD under tension. Increasing the number of loops has also been shown to have almost no effect on overall stiffness or tensile friction, while increasing tensile strength.

[0109] For example, a knitted traction device for a 5French (5F) reverse support catheter, which can be introduced via a 6French (6F) tube, can be constructed of 0.0012” (nickel-titanium alloy) filaments with 28-34 loops per turn to avoid locking when pulled (e.g., with a force of up to 200g). The traction device tube is longer than 20cm (e.g., it can be 140cm or longer) and can have a loop length / diameter ratio greater than 7, and can ride (straddle) within 1mm of the outer diameter of the reverse support catheter in a relaxed configuration.

[0110] In another example, a knitted traction device for a 9French (9F) reverse support catheter, which can be inserted through a 10French (10F) tube, can be constructed of 0.0022” (nickel-titanium alloy) filaments with 24-32 loops per revolution to avoid locking when pulled (e.g., with a force up to 200g). The traction device tube is longer than 20cm (e.g., it can be 140cm or longer) and can have a loop length / diameter ratio greater than 7, and can ride within 1mm of the outer diameter of the reverse support catheter in a relaxed configuration.

[0111] Device configured to ingest hard materials

[0112] This article also describes a device that includes an expandable funnel at the end of a reversing support conduit, wherein the puller is wound and reversed on the reversing support conduit, and these funnels can be modified or configured to facilitate the removal of hard materials (e.g., clots), which prevents the puller from retracting the hard material into the conduit.

[0113] This device is applicable to any type of traction device (not limited to knitted traction devices), including other braided traction devices, laser-cut traction device tubes, etc. The traction device is typically arranged to reverse at an expandable funnel at the distal end of the reversing support conduit, such that as the interior (reversed) of the traction device is drawn into the funnel, the exterior of the traction device extends proximally along the reversing support conduit, thereby compressing the material, such as clots, and removing fluid held (e.g., gripped) by the traction device from the material, and pulling the reversing traction device into the reversing support conduit until the entire clot is captured. While the use of a funnel at the end of the reversing support conduit is particularly useful for removing large (e.g., larger diameter) clots, in some cases, especially with harder materials, the internal shape of the funnel has unexpectedly been found important in the device's ability to compress and draw material into the reversing support conduit.

[0114] This document describes an apparatus comprising a reversible support conduit with a funnel, which is particularly well-suited for grasping and removing clots (specifically large-diameter clots) by using a reversible support conduit including an expandable funnel at its distal end. The collapsible / expandable funnel can be configured to operate with a compressive force applied by pulling a flexible tube into the reversible support conduit, causing it to reverse into the reversible support conduit, thereby capturing the clot. The collapsible / expandable funnel can be configured to present a fully expanded, latching (e.g., “locked”) configuration when a lateral compressive force is applied to the distal end face of the funnel by the flexible tube. Furthermore, the funnel may include openings (described herein as having a porous structure) through which fluid squeezed out of the clot as it is moved into the narrower diameter lumen of the reversible support conduit and compressed can exit the funnel laterally. For example, openings in a collapsible / expandable funnel (which may simply be referred to herein as an expandable funnel) that allow fluid to exit laterally from the funnel wall when the clot is compressed can also prevent clot blockage or clogging.

[0115] The interior of the funnel described herein can be shaped such that material drawn into the funnel is retained within it, allowing it to disintegrate and be compressed within the funnel without causing jamming of the aspirator, thus preventing the aspirator from pulling and / or other clots within the aspirator. Therefore, in the methods and apparatus described herein, the distal region of the inverted support conduit is configured as a collapsible and / or expandable funnel. The expandable funnel apparatus described herein may also, or alternatively, be adapted to prevent jamming of the aspirator in the distal opening of the funnel, including when the apparatus is used to remove large and / or hard clots. In some variations, these funnels may be adapted to include an inner wall within the funnel that divides the funnel into sections, such as smaller sections at the proximal (i.e., narrower) end of the funnel (e.g., 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, etc.), which may have a steeper angle relative to the more distal end. In some variations, the funnel cavity comprises two or more chambers separated by narrowing or contraction zones. These adjustments to the funnel cavity allow harder lumps to remain inside the funnel as the puller is drawn in and through the clogged lumps, thus aiding in the breaking up of the harder lumps.

[0116] Any device described herein can be a device for removing material from a blood vessel, including a reversing support (which includes a catheter having a catheter lumen and an elongated and flexible catheter body) and an expandable funnel disposed at the distal end of the catheter body. The funnel extends along a distal-proximal axis, wherein the distal end of the funnel defines a distal opening communicating with the interior of both the funnel and the catheter lumen.

[0117] A funnel that helps break up and compress harder materials may include two or more regions within the funnel cavity. For example, in some variations, the open configuration within the funnel may have a wall angle of less than 14 degrees relative to the proximal-distal axis over most (e.g., >50%, or in some variations >55%, >60%, >65%, >70%, >75%, >80%, etc.) of the funnel length, and may include a first region with a wall angle between 14 and 50 degrees relative to the proximal-distal axis. The device also typically includes a retractor comprising a flexible tube extending distally along the outer surface of the catheter in an unreversed configuration, which inverts at the distal opening and extends proximally within the catheter lumen in a reversed configuration. The flexible tube may be configured to invert by rolling (winding) over the distal opening (winding along the distal opening) when the first end of the retractor is pulled proximally within the catheter lumen.

[0118] Figure 6 The diagram illustrates something similar to... Figure 1AAn example of the inverted tube device 601 is shown. In this example, the inverted tube device is located in a large blood vessel with a clot having a diameter greater than twice (2×) the inner diameter of the support catheter. Although the clot can be taken in and removed by the inverted tube device 601 with an inverted support catheter of a narrower diameter, the inversion is inefficient, for example, requiring a flexible tube many times longer than the length of the clot tube to capture the entire clot. Capture is even more complicated if the clot is or includes a hard material (including calcified materials, etc.). Figure 6 The illustration depicts a problem solved by the apparatus described herein; specifically, how to efficiently feed large-diameter and / or hard clots into a relatively small-diameter inversion tube apparatus. In this example, while clots of 10 mm or larger diameter can be drawn into the 3 mm diameter (e.g., 8 French) inversion support conduit of the inversion tube apparatus, efficiency would be low because the length of flexible tube required to capture the clot along its entire length would be very long. In some cases, if the clot contains a hard, incompressible material, it may not be able to be fully engulfed. The inversion tube apparatus described herein addresses and improves the efficiency of this operation in several ways.

[0119] Specifically, the methods and reversing tube devices described herein dehydrate the clot (when it is drawn into the reversing tube device). The clot (including even hard or partially calcified clots) may contain a large amount of fluid that can be compressed and removed by the reversing tube device described herein. For example, the flexible tube is typically porous and may be, for example, a braided and / or knitted material. Additionally, in some variations, the distal region of the reversing support tube may be configured to be specifically porous in the distal region (e.g., distal 5 mm, distal 4 mm, distal 3 mm, distal 2 mm, distal 1 mm, distal 0.9 mm, distal 0.8 mm, distal 0.75 mm, distal 0.7 mm, distal 0.6 mm, distal 0.5 mm, distal 0.4 mm, etc.) to allow fluid from the clot to leak laterally from the reversing support tube when the clot is drawn into the elongated reversing support tube, allowing the clot to be compressed efficiently rather than stretched or elongated. Specifically, the apparatus and method described herein include a funnel-shaped distal end on a reversing support conduit, which may be porous (specifically in the region near the base of the funnel) to allow compression of the clot material and fluid from the clot to be laterally discharged / removed from the side of the reversing support conduit when the clot is drawn proximally into the reversing support conduit by a flexible tube (e.g., a puller). The funnel may be expandable (also referred to herein as collapsible) and may be integral with or attached to the distal end of the reversing support conduit. The funnel may be collapsible and guided through a sleeve / guide tube (e.g., an intermediate conduit) such that it can be fitted in a collapsible state into a 6-French, 8-French, 10-French, 12-French, 14-French, 16-French, 28-French, 20-French, and / or 24-French sleeve. The expandable funnel may be self-expanding. Alternatively or additionally, the expandable funnel at the distal end of the reversing support conduit can be expanded by actuation of a flexible tube; for example, pulling the flexible tube proximally into the reversing support conduit to cause the flexible tube to roll on the distal end of the reversing support conduit can apply a proximal compressive force that pulls and expands the expandable funnel. The maximum outer diameter of the funnel can be greater than twice the maximum outer diameter of the converging configuration (e.g., greater than 2.5 times, greater than 3 times, greater than 3.5 times, greater than 4 times, greater than 4.5 times, greater than 5 times, etc.); the maximum outer diameter of the funnel in the converging configuration can be approximately the same as or slightly larger than the maximum outer diameter of the main body region of the reversing support conduit (e.g., 1 time, 1.0 time, 1.1 time, 1.2 time, etc., of the proximal outer diameter of the reversing support conduit). In some variations, the funnel has an outer diameter between 2 and 26 mm.

[0120] In any of these variations, the flexible tubing can also be adapted to better engulf and compress large-diameter clots. For example, a flexible tubing in a non-inverted configuration, positioned outside an inverted support catheter (e.g., in a blood vessel), can have an outer diameter that is approximately the same as or larger than the maximum outer diameter of the open configuration of the funnel. An expandable funnel allows the flexible tubing (e.g., a braided traction device) to grip the clot at the edge of its cross-section rather than at the center, enabling more efficient clot intake. However, in some variations, funnels, and specifically funnels with low wall angles (e.g., 14 degrees or less), may struggle to handle hard materials (e.g., calcified materials).

[0121] In the flexible tube variations described herein (e.g., tractioner variations), it is advantageous to heat-shape the non-reversing outer diameter of the expanded flexible tube (e.g., the portion of the flexible tube on the outside of the reversing support catheter before being pulled into the catheter and reversed) to a diameter (OD) larger than the maximum outer diameter of the expansion funnel, and preferably as large as possible relative to the clot OD. A larger OD flexible tube can have higher efficiency in gripping and compressing the clot. This is independent of the presence of a funnel at the distal end of the reversing support catheter. For example, with respect to flexible tubes made of braided material (e.g., tractioners), the OD of the reversing flexible tube can be selected to be at least 1 / 3 of the clot OD (or vessel ID), for example, an expanded non-reversing flexible tube can have an OD greater than or equal to about 50%, 60%, 70%, 80%, 90%, 100%, or 110% of the clot OD (or vessel ID).

[0122] The distal end of the inverted support conduit, specifically the expandable funnel at the distal end, can be porous. The ability to allow fluid from the compressed clot to exit through the sidewalls of the funnel's inner diameter (e.g., laterally to the walls of the inverted support conduit, rather than just from the distal and proximal ends) provides a place for the fluid removed from the clot to reach and improves the efficiency of the device, allowing the removal of clots of similar length with a much shorter, flexible tube. If lateral leakage of the clot is not allowed (e.g., when using a non-porous funnel), the removed fluid will accumulate at the base of the funnel and reduce clot efficiency. Therefore, in some variations, the funnel is porous, or at least locally porous, for example, near the base of the funnel (where the clot's compressibility is highest).

[0123] In any of the variations described herein, the inverted support tube can be relatively large, such that the clot does not necessarily have to be compressed as much as possible. In peripheral vessels, for example, the inverted support catheter can have an outer diameter greater than 1 mm, such as greater than 1 mm, 1.2 mm, 1.4 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc.

[0124] In general, any device described herein can also improve the efficiency of a device for removing clots by reducing the force required to remove them. For example, the methods and devices described herein may include a smooth material at the distal end of the inverted support conduit (e.g., a funnel). For example, in any of these devices, the funnel may be lined with a smooth material (e.g., a PTFE lining that produces lower ingestion pull and / or reduces ingestion efficiency). A smooth funnel allows clots to be drawn into the opening of the funnel rather than pulled into the conduit.

[0125] In some variations, the funnel may be configured with a specific shape (e.g., conical), which may also help improve the efficiency of compression and / or dehydration of the clot and may help reduce the force required. For example, in some variations, a longer funnel may have a lower intake force and better clot intake efficiency compared to a shorter funnel with the same maximum OD / minimum ID. Examples of funnels may have maximum ODs of, for example, 3 mm, 5 mm, 6 mm, 8 mm, 10 mm, 12 mm, 15 mm, 20 mm, 25 mm, etc. Exemplary funnel lengths may be, for example, 5 cm, 10 cm, 15 cm, 20 cm, 25 cm, 30 cm, 40 cm, 50 cm, 100 cm, etc. The main body of the slender, flexible, inverted catheter can be a catheter of, for example, 3French(F), 4F, 5F, 6F, 7F, 8F, 9F, 10F, 11F, 12F, 14F, 16F, 18F, 20F, 25F, etc.

[0126] Regarding variations in which the flexible tube incorporates braided material, a thicker braid can result in increased efficiency. For example, a greater number of braided "finger-like structures" (e.g., loops) (per braid circumference) in the transverse direction of the tube can lead to greater clot ingestion efficiency. For instance, the number of gripping fingers could be at least 10, 20, 30, 40, 50, 60, 100, etc., per circumference of the tubular braid.

[0127] Generally, the reversing tube devices described herein can be highly flexible before actuation and during operation. For example, a flexible tube (e.g., a retractor) may not significantly increase the stiffness / flexibility of the conduit (specifically, the distal region of the conduit) of the elongated reversing support to avoid affecting operability. The flexible retractor tube section described herein increases the stiffness of the last y cm of the conduit (e.g., the distal 20 cm, 18 cm, 15 cm, 12 cm, 10 cm, 9 cm, 8 cm, 7 cm, 6 cm, 5 cm, 4 cm, 3 cm, 2 cm, 1 cm, etc.) by less than a predetermined percentage (e.g., less than 10%, 12%, 15%, 18%, 20%, 25%, 30%, etc.). For example, the flexible retractor tube section described herein, which extends beyond the conduit and reverses backward at the distal end of the conduit, increases the stiffness of the distal 5 cm of the conduit by less than 15% compared to the case where no flexible tube extends through it and folds backward in the distal direction of the conduit.

[0128] As described above, the flexible tube (e.g., the retractor) can be a woven, braided, and / or knitted material. With regard to woven and braided materials (which may include multiple fibers woven or braided to form a reversing tube), these structures can be adjusted to prevent jamming and / or reduce the force required to pull the retractor and to allow reversal above the catheter tip. For example, a mechanical plaque removal device may include a knitted or braided flexible tube that can roll freely near the catheter tip, even in tortuous anatomical structures, and when gripping clots by adjusting one or more braided structures; thereby minimizing the braid angle; including a hydrophilic coating on the distal aspect of the catheter's outer diameter (OD) or on the inner diameter (ID) of the braid (e.g., the retractor); thereby including arcuate walls on the catheter; and / or increasing the stiffness of the distal tip region relative to the adjacent proximal region. Alternatively, it is advantageous to have a hydrophilic coating on the distal ID at 1, 3, 5, 10, or 15 cm, or even on the entire catheter ID.

[0129] As described above, the flexible tubing (e.g., the retractor) can be braided, woven, knitted, etc., and can be configured to converge as small as possible into the inner diameter (ID) of the catheter. The retractor can converge to a value greater than, equal to, or within 90%, 85%, 75%, 70%, 65%, 60%, or 50% of the catheter inner diameter (ID) / catheter tip OD, because this ID is based on the elongated body region of the reverse-supporting catheter, which can create axial tension on the retractor (e.g., braided, knitted, etc.) when the retractor is pulled around the catheter tip, which can inadvertently and undesirably cause the retractor to become stuck on the catheter tip. When the retractor is pulled around the catheter tip, the retractor can be pulled in an axial direction, thus creating axial tension in the retractor structure as the retractor is pulled through the catheter ID. By engaging the retractor element at 90%, 85%, 75%, 70%, 65%, 60%, or 50% of the catheter ID (or, in some variations, OD), the retractor is less likely to grip / synchronize downwards onto the catheter tip when radially tightened, thus helping the braid to roll around the catheter tip with a smaller axial force applied by the user. If the user requires a smaller axial force to pull the retractor along the tip, the catheter tip is less likely to bend or deflect when the retractor is retracted. Minimizing the likelihood of the catheter tip bending is advantageous. The retractor can be adjusted to "lock" at a specific ID by controlling any of the following variables, and any combination thereof: selecting a specific number of braided ends; selecting the size / diameter of the braided ends; selecting the braiding material (e.g., multifilament or monofilament); heat-setting the twill on the braid (e.g., braid diameter); and selecting the braiding pattern, such as 1×2, 1×1, or any other pattern.

[0130] This minimizes the braid angle to prevent the puller from locking (sticking) at the catheter tip opening. Generally, the lower the braid angle (e.g., 45 degrees or less, 40 degrees or less, 35 degrees or less, 30 degrees or less, 25 degrees or less, 20 degrees or less, etc.), the less likely it is to have a braided cross at the capture point on the catheter tip.

[0131] In any of the variations described herein, the surfaces of the catheter and / or retractor may be coated to enhance swirling over the distal region of the catheter. It is useful to have a hydrophilic coating on the distal side of the catheter OD or on the ID of the retractor, allowing the retractor to glide more easily over the distal end of the catheter and near the tip when pulled through the interior of the catheter.

[0132] The distal stiffness of the elongated reversible support catheter can be sufficiently rigid to prevent folding when the retractor is pulled; it can also be smooth (e.g., using a coating or material property). The distal portion of the elongated reversible support catheter tip (e.g., the last 5 mm) can be made of a material that is both sufficiently rigid and sufficiently smooth so that the distal tip of the catheter does not fold inward or bend when the braided structure is rolling near the tip. Therefore, the distal tip can have greater stiffness than the more proximal region of the distal end of the catheter.

[0133] Figures 7A-7B and Figures 8A-8B The illustrations depict examples of reversing tube devices, each comprising a funnel region at the distal end of a reversing support conduit. In this example, the funnel comprises two regions: a first region 350 with a wall angle of less than 14 degrees (which includes >60% of the inner wall of the funnel), and a second, more proximal region 351 with a wall angle of >15 degrees (extending to approximately 30% of the inner wall of the funnel). Therefore, Figure 7A A first variation of the reversing tube device 300 is shown, which includes an elongated, flexible reversing support conduit 307 having an expandable funnel 308 at its distal end. Figure 7A The diagram shows a converging configuration, located inside the central (e.g., delivery) conduit 309, and... Figure 7B The diagram shows the funnel in an open configuration after being released from the intermediate conduit. The funnel can be made of a woven material and can be porous, specifically porous in the base region 313, where the funnel extends from the elongated body of the inverted support conduit. A flexible tube 305 extends over the distal end of the inverted support conduit (including the funnel) and inverts at the distal opening of the funnel. The flexible tube can be, for example, a knitted material and can be biased in the open configuration to expand to an outer diameter (OD) greater than the outer diameter of the funnel 308. The flexible tube is attached to the distal region of the pull rod 303. Figures 7A-7B In the example shown, the pull rod extends further distally 315 compared to the distal end of the funnel, as illustrated. Although a flexible tube (e.g., a puller) is attached to the distal region of the pull rod, in this example, the end of the flexible tube is attached to the proximal side of the distal end of the device.

[0134] exist Figures 8A-8B In the example of the reversing tube device 400 shown, the flexible tube 405 is attached to the distal region of the pull rod 403 closer to or located at the distal end of the pull rod. Figure 8AA reversing tube device 400 is shown inside an intermediate conduit (e.g., a delivery conduit) 409, having a funnel 408 located in a converging configuration at the distal end of a reversing support conduit 407 and within the intermediate conduit. This funnel may include one or more (e.g., multiple circumferentially arranged) openings or holes in the base 413 region to allow fluid to exit the reversing support conduit from the clump when the clump is pulled into the reversing support conduit by rolling a flexible tube 405 (e.g., a traction zone). Figure 8B A device is shown that allows placement at least partially from an intermediate conduit 409, wherein an expandable funnel 408 is expanded. (As shown in...) Figure 7A and Figure 7B , Figures 8A-8B The funnel in the middle consists of two regions with different wall angles.

[0135] Figure 8C This is another example of a device 400', in which the inverted support conduit 407' includes an expandable funnel 408' (illustrated as expanding) having multiple regions (with different wall angles) within the funnel cavity. As in Figures 8A-8B In this device, when used as a thrombectomy apparatus, the flexible traction device 405' can be rolled and reversed to capture clot material. Figure 8C The flexible tube can be a knitted tube, thus forming multiple loops or fingers at the distal end of the device, thereby helping to capture clumped material. This is in Figure 9A and Figure 9B A more detailed illustration is shown below. In this example, the traction device is configured (as described above) to fit more closely to the outside of the inverted support conduit, as shown in the figure.

[0136] exist Figure 9A and Figure 9B An example of a porous funnel 508 constituting the distal end of the reversing support conduit 507 is illustrated, having a knitted flexible tube 505 that is shown to reverse direction and enter the funnel when the flexible tube is pulled proximally into the funnel. As described herein, the interior of the funnel (funnel cavity) may be configured with different wall angles and / or may include one or more contraction zones. The inner wall angle of the funnel may differ from the outer wall angle of the funnel.

[0137] Any suitable expandable funnel-shaped distal end can be used. For example, Figures 10A-10C The illustrations depict different variations of the funnel-shaped distal end with different outer surface shapes. Figure 10A In this process, the funnel 1013 may be solid, or may include openings for allowing fluid (e.g., it may be porous) to pass through, and may be porous over its entire surface or a portion thereof. Figure 10B This illustrates an example where only a portion of the expandable funnel is porous. Figure 10BIn the middle, the base region 1023 is porous and has multiple openings arranged circumferentially around the base region of the funnel 1013.

[0138] Figure 10C The expandable funnel 1013 variant illustrated in the middle is porous along its entire length and is depicted as being made of a woven material (e.g., metal or polymer fiber) that can fold itself to form a funnel shape, and includes a flexible reversible support conduit 1007.

[0139] Figures 11A-11D The illustration shows an example of the distal end of a reversal support conduit including a funnel. In this example, the funnel is integrally formed with the body of the reversal support conduit. (As shown in...) Figure 11A As shown in the schematic diagram, the funnel shape includes a frame composed of multiple fingers or struts 1111, formed, for example, by cutting (e.g., laser cutting) the distal end of the body of the inverted support conduit 1107. Figure 11A In the middle, the woven or machine-woven funnel body 1118 is attached to the support rod; the machine-woven body 1105 is attached at one end to the body of the reverse support guide tube, and at the other end 1109 it is locked in place on the support rod. Figure 11B An example of the body of an elongated support conduit is shown, which has been cut into multiple struts or fingers thereon to support the funnel body, such as... Figure 11C As shown in the diagram, the distal end of the funnel 1131 is open and can extend beyond the support rod and be locked to form an open configuration with high compressive strength, even without the support rod or fingers below. Figure 11D An example of the open distal end of the funnel of the device is shown.

[0140] Figure 12 yes Figure 11C The diagram shows an enlarged view of the distal end of the funnel, illustrating the application of an axial compressive force that causes the distal end of the device to "jam" and form a larger weave angle at that distal end compared to the uncompressed, more proximal end. This compressive force helps to open (and keep open) the expandable funnel.

[0141] Figures 13-14 The illustration depicts a funnel 2200 formed by adding braided wall material to the distal bifurcation of a reverse support conduit. The inner and outer walls of the braided material constituting this funnel can be jointly sutured with sutures 2221 arranged radially around the funnel, thus limiting its further expansion, as described above. These bifurcations can slide axially relative to the inner and outer walls. In any funnel described herein, the mesh material constituting the inner and outer walls can extend further distally than the distal end of the bifurcation. In the relaxed configuration, the braid length distal to the distal end of the bifurcation 2214 is illustrated as a distance x 1 mm. Figure 14 The diagram shows a funnel formed by the compression of the braided fabric 2213, as would occur when a puller (e.g., a flexible tube) is loaded over the funnel and pulled axially along its proximal length into a reversing support conduit. In this configuration, the axial length of the braided wall extends beyond the tip of the bifurcation by up to x2 mm.

[0142] In some variations, it is advantageous to limit the axial length of the braided wall extending beyond the tip of the bifurcation in a fully expanded (e.g., extruded) configuration. This prevents instability, specifically lateral instability. For example, it is advantageous to limit the axial length of the braided wall extending beyond the tip of the bifurcation in a fully expanded (e.g., extruded) configuration to 10 mm or less (e.g., 8 mm or less, 7 mm or less, 6 mm or less, 5 mm or less, 4 mm or less, 3 mm or less, 2 mm or less, for example, between 1 mm and 10 mm, between 1 mm and 8 mm, between 1 mm and 7 mm, between 1 mm and 6 mm, between 1 mm and 5 mm, between 1 mm and 4 mm, etc.). Specifically, it is advantageous to limit it to 5 mm or less.

[0143] Any of the devices described herein can be modified to make the funnel more easily compress hard materials. For example, in some variations, the device may be configured such that the funnel includes a bulge or a larger diameter region near the proximal end of the funnel (e.g., a region with a larger wall angle, such as a region between 15 and 50 degrees). This can be formed, for example, by modifying the stitching of the mesh that forms the inner wall of the funnel. In some variations, the funnel may have a length between 15 and 40 mm (e.g., between 15 and 35, between 15 and 30, between 15 and 25, between 15 and 20, etc.). In some variations, the funnel may be configured to reduce the cross-section inside all or a region of the funnel cavity. In some variations, one or more protrusions that may help break up harder materials (e.g., clots) may be present in the funnel. These protrusions may be configured to project into the inner cavity of the funnel but may allow a tractor to move over and / or around the protrusions.

[0144] Figures 15A-15B The illustration shows an example of a funnel, displaying its external view. Figure 15A The funnel shown has a very narrow outer profile (e.g., 7 degrees or less, with a maximum outer wall angle of α1505). Figure 15B One example shown has an initial (proximal) outer wall angle α21509 of approximately 15 degrees for the first 25% of the length of the expanding funnel, followed by an outer wall angle α11507 of less than 10 degrees for the remaining length of the expanding funnel.

[0145] Figures 16A-16D An example is shown of the profile of a funnel having two or more regions with different inner wall angles. For example, in Figure 16A In this device, the device includes an initial proximal region of the funnel cavity, a wall angle β1613 of approximately 14 degrees (or greater) on this initial region 1605, and a more distal region 1607 with a wall angle (1611) of 10 degrees or less. For example, in Figure 16A In the distal-proximal axis, the region of the funnel cavity 1604 with a wall angle of less than 14 degrees (α1611) accounts for approximately 65%, while the region with a wall angle of 14 degrees or greater (β1613) accounts for approximately 35% of the funnel length. The outer side of the funnel is continuous and may have a different profile than the funnel cavity; for example, the outer wall angle may be less than 14 degrees over the entire length, as shown in the figure.

[0146] Similarly, in Figure 16B In this device, the initial proximal region of the funnel cavity (which has a wall angle (β1613') of approximately 30 degrees above this initial region 1615) and a more distal region 1617 with a wall angle 1611' of 10 degrees or less. For example, in Figure 16B In the distal-proximal axis direction, the region of the funnel cavity 1604' with a wall angle of less than 14 degrees (α1611') is approximately 75% of the funnel length, while the region with a wall angle of 30 degrees (β1613') is approximately 25% of the funnel length. The outer side of the funnel is continuous and may have a different profile than the funnel cavity; for example, the outer wall angle may be less than 20 degrees over the entire length, as shown in the figure.

[0147] exist Figure 16C In this device, the device includes an initial proximal region of the funnel-shaped cavity with a wall angle β1613” of approximately 50 degrees above this initial region 1625, and a more distal region 1627” with a wall angle 1611 of 7 degrees or less. For example, in Figure 16C In the distal-proximal axis, the region of the funnel cavity 1604” with a wall angle of less than 7 degrees (α1611”) is approximately 75% of the funnel length, while the region with a wall angle of 50 degrees (β1613”) is approximately 25% of the funnel length. The outer side of the funnel is continuous and may have a different profile than the funnel cavity; for example, the outer wall angle may be less than 30 degrees over the entire length, as shown in the figure.

[0148] Figure 16D Another example is shown, in which the funnel cavity has three regions with different wall angles, as illustrated in the figure. Figure 16DThe device comprises an initial proximal region 1639 of the funnel cavity with a wall angle α2 1612 of approximately 10 degrees above this initial region 1639, a central region 1635 with a funnel wall angle β1 1613'" of approximately 14 degrees (or greater), and a more distal region 1637 with a wall angle 1161"" of 10 degrees or less. In the distal-proximal axial direction, the total length of the regions of the funnel cavity 1604'" with wall angles less than 14 degrees (1637 and 1639) is approximately 75% of the funnel length, while the region 1639 with a wall angle of 30 degrees is approximately 25% of the funnel length. The outer side of the funnel is continuous and may have a different profile than the funnel cavity; for example, the outer wall angle may be less than 20 degrees over its entire length, as shown in the figure.

[0149] exist Figures 16A-16D In this context, the wall angle of the funnel cavity is a measure of the acute angle facing distally between the inner wall of the funnel and the distal-proximal axis 1608. Any of these variations can be constructed as described above, forming inner arms or forks that are bent or constructed to form the described inner wall angle and are covered in a mesh (e.g., a woven or knitted mesh).

[0150] In some variations, the funnel can be configured such that the inner cavity includes one or more contraction zones (narrowing zones) within the funnel. For example, in Figures 17-18B This is illustrated in the diagram. This configuration also allows the device to capture and remove materials with varying degrees of hardness (e.g., from soft to hard). For example, in Figure 17 In this design, at the end of the reversing support conduit, a prototype funnel is formed by branching or arming and attaching a mesh from woven material. In this example, the funnel's inner cavity includes two narrowing zones within the funnel cavity inner diameter (ID). By controlling the shape of the funnel inner diameter, the path followed by the traction device when reversing into the funnel also changes, which improves the device's intake characteristics.

[0151] exist Figure 17 In the middle region 1709, the mesh forming the inner cavity of the funnel 1700 narrows to form a single narrow section in the inner diameter of the funnel. This can be achieved by, for example, a ring, suture, or other element that restricts the expansion of the wall in this region. Figures 18A-18B The illustration depicts another example of a funnel (shown in cross-section), showing two narrowing zones. In this example, the first narrowing zone 1815 can be formed as described above and includes a wall angle of approximately 30 degrees (shown in...). Figure 18BThe funnel consists of a first zone, a second zone with a negative wall angle of approximately -15 degrees (e.g., β1), a third zone with a wall angle of approximately 35 degrees (α2), and a nearest-side zone with a wall angle of approximately -2 degrees (β2). Thus, the interior of the funnel comprises two narrowing zones that constitute three consecutive regions into which material can be drawn. In some variations, the reduction in funnel ID can be between 10% and 90% of the maximum funnel ID. The inner diameter reduction narrowings are located at discrete positions between the funnel base and the top. Similarly, the respective measurements of multiple inner diameter structures or reductions (e.g., two or more) within the funnel's interior lumen can be between 10% and 90% of the maximum funnel inner diameter and can be located at discrete positions between the funnel base (at the connection to the conduit lumen) and the distal open end of the funnel.

[0152] As described above, any of these funnels may include a porous structure, thereby allowing clots or tissue to be partially dehydrated as they are drawn into the base of the funnel by allowing fluid to leak through the sides of the funnel. The funnels described herein may have a smooth transition from the funnel ID to the conduit ID. This can be achieved by laser-cutting a bifurcation at the distal end of the conduit, as shown in the figure. In these examples, the porous structure and / or smooth transition may also be provided by a porous metal mesh (e.g., braided) structure forming the wall.

[0153] The reverse support conduit described and illustrated herein is suitable for preventing collapse, even when forces are applied by a flexible tube in the absence or presence of clotted material. In any of these variations, the funnel needs to be able to withstand axial loads exceeding 1, 2, 3, 4, 5, 10, 15, and / or 20 kg (e.g., loads applied along the axis of the conduit shaft length) without collapse, for example, when there is resistance to clot ingestion, while still allowing the flexible tube (e.g., a puller) to roll around the top of the funnel and into the reverse support conduit. Axial stiffness can be at least partially achieved by configuring the braided wall of the funnel to have a squeeze-clamp configuration at the top (as described above). Axial stiffness can also be improved by limiting the length of the braided wall extending beyond the distal top of the bifurcation in the squeeze-clamp configuration (e.g., to 5 mm or less). In some configurations, axial stiffness can also be improved by including circumferential supports (e.g., filaments) between the bifurcations (as described above). This can disperse the load applied to the top of the funnel by the traction device, so that the top of the funnel remains round and no finger becomes separated and collapses.

[0154] Generally, these same factors can also improve radial stiffness. The ends of the funnel can also preferably be sufficiently rigid to prevent the funnel from folding radially when the traction device rolls near the top. The radial stiffness of the funnel can be at least partially obtained by arranging the woven walls of the funnel in a squeezed configuration at the top (as described above). Radial stiffness can also be improved by limiting the length of the woven walls extending beyond the distal top of the bifurcation in the squeezed configuration (e.g., to 5 mm or less). In some configurations, radial stiffness can also be improved by including circumferential supports (e.g., filaments) between the bifurcations (as described above), which can distribute the load applied from the traction device to the top of the funnel so that the top of the funnel remains round and no finger becomes separated and collapses.

[0155] Therefore, in any funnel described herein, the funnel may be composed of multiple branches or arms to which a mesh forming the inner and / or outer walls is attached. As briefly described above, it is advantageous to allow the mesh to extend and retract relative to the branches, such that they can present a jammed angle, thereby keeping the funnel open when force is applied by pulling a traction device into the distal opening of the funnel.

[0156] However, in this variation, it is important to prevent the branching from extending further outwards from the net, such as... Figure 19 As shown. In Figure 19 In the exemplary funnel 1900 shown, these branches protrude from the distal end of the funnel 1909. This creates one or more areas where the puller (which may be, for example, a knitted material) is tripped or caught. Therefore, it is ideal to prevent the branches from protruding from the distal end of the funnel. Figure 20A As shown, this can be achieved by using one or more bridging elements 2007 (such as stitches, e.g., restraining filaments) that join together between the funnel bifurcations to prevent the bifurcations 2005 from extending distally from the woven material constituting the funnel wall. In this example, the stitches can restrict the funnel bifurcations from extending from the woven material constituting the outer wall of the funnel.

[0157] The constraint filaments, referred to herein as circumferential supports, extend radially around the funnel surface and limit the maximum outer diameter of the expandable funnel. The constraint filaments are held in positions between bent bifurcations (e.g., Figures 20A-20B In the variant shown, the constraint filament must be constrained proximally to prevent it from sliding backward (proximally) while allowing the fork to protrude into the web, as... Figure 20B As shown in the diagram. Because without proximal restraint, the traction device will compress (and open) the funnel proximally with greater force, allowing displacement of the restrained filament, even if the filament has been glued (e.g., by adhesive) in place. Figure 20B As shown, this can cause the suture (or some other restraining filaments) to shift proximally.

[0158] Figures 21A-21D The illustration depicts an example of a design configured to form a proximal constraint structure for restraining the filament from the fork. In this example, each fork 2100 can be cut or shaped to include one or more (e.g., two) protrusions 2104. Figure 21A In the middle, the fork that will fold above the marked area 2106 can be cut 2108 to form two protrusions 2104, 2104' (shown in Figure 21B These protrusions can form a proximal constraint structure. Figure 21C This illustrates the placement of sutures that allow the curved area (protrusions 2104, 2104') to constrain the filament by folding at the distal end of the bifurcation (as shown in the figure), constraining the filament and thus enabling it to be secured. Figure 21D (as shown in the image).

[0159] Figure 22A and Figure 22B The side and end views of the bifurcation are shown, including the formed proximal constraint structure that holds the constraint filament distally to prevent it from shifting proximally and thus preventing the bifurcation from extending distally from the net that forms the funnel wall.

[0160] In any funnel described herein, the funnel may be configured such that it expands sufficiently only when an axial load is applied, for example, when a flexible tube (e.g., a retractor) is pulled proximally and rolled into a reverse support catheter. This allows the funnel to travel in smaller vessels before it is actuated.

[0161] When a feature or element is referred to herein as being “on” another feature or element, it may be directly on the other feature or element, or there may be intermediate features and / or elements. Conversely, when a feature or element is referred to as being “directly on” another feature or element, there are no intermediate features or elements. It should also be understood that when a feature or element is referred to as being “connected,” “attached,” or “joined” to another feature or element, it may be directly connected, attached, or joined to the other feature or element, or there may be intermediate features or elements. Conversely, when a feature or element is referred to as being “directly connected,” “directly attached,” or “directly joined” to another feature or element, there are no intermediate features or elements. Although one embodiment has been described or illustrated, the features and elements thus described or illustrated can be applied to other embodiments. Those skilled in the art will also understand that a structure or feature arranged in a position “adjacent” to another feature may have portions that cover or lie beneath the adjacent feature.

[0162] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. For example, the singular forms “a,” “an,” and “the” as used herein are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the words “comprise” and / or “comprising,” when used in this specification, specifically describe the presence of stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The words “and / or” as used herein include any and all combinations of one or more associated listed items and may be abbreviated as “ / .”

[0163] Spatial relative terms such as “below,” “under,” “down,” “above,” “up,” etc., may be used herein for ease of description to describe the relationship of one element or feature to another, as illustrated in the accompanying drawings. It should be understood that, in addition to the orientations depicted in the drawings, spatial relative terms are intended to encompass different orientations of the device in use or operation. For example, if the device in the drawings were reversed, an element described as below or under other elements or features would be positioned above those other elements or features. Thus, the exemplary term “below” can encompass both above and below orientations. The device may be oriented (rotated 90 degrees or in other orientations) and the spatial relative descriptions used herein shall be interpreted accordingly. Similarly, the terms “up,” “down,” “vertical,” “horizontal,” etc., used herein are for illustrative purposes only, unless otherwise specifically stated.

[0164] Although the terms "first" and "second" may be used herein to describe various features / elements (including steps), these features / elements should not be limited by these terms unless the context clearly indicates otherwise. These terms may be used to distinguish one feature / element from another. Thus, the first feature / element discussed below may be referred to as the second feature / element, and similarly, the second feature / element described below may be referred to as the first feature / element without departing from the teachings of the invention.

[0165] Throughout this specification and claims, unless the context otherwise requires, the word "comprise" and variations such as "comprises" and "comprising" mean that various components can be used together in these methods and articles (e.g., compositions and apparatuses that include devices and methods). For example, the word "comprising" will be understood to mean the inclusion of any stated element or step but not the exclusion of any other element or step.

[0166] In general, any apparatus and method described herein should be understood as inclusive, but alternatively all components and / or steps or subsets of components and / or steps may be exclusive and may be expressed as “consisting of ---” or alternatively “consisting substantially of ---” various components, steps, sub-components or sub-steps.

[0167] As used herein in the specification and claims, including as in the examples, and unless expressly stated otherwise, all figures may be read as if the words “about” or “approximately” were used prefaced, even if the term is not explicitly stated. The phrase “about” or “approximately” may be used when describing a quantity or location to indicate that the described value and / or location is within a reasonably expected range of values ​​and / or locations. For example, a numerical value may have a value (or range of values) of + / - 0.1% of the stated value, + / - 1% of the stated value, + / - 2% of the stated value, + / - 5% of the stated value, + / - 10% of the stated value, etc. Any numerical value given herein should also be understood to include about or approximately that value, unless the context otherwise indicates. For example, if the value “10” is disclosed, then “about 10” is also disclosed. Any range of numerical values ​​described herein is intended to include all subranges contained therein. It should also be understood that when a value is disclosed as "less than or equal to" that value, "greater than or equal to" that value and possible ranges between those values ​​are also disclosed, as would be appropriately understood by those skilled in the art. For example, if the value "X" is disclosed, then "less than or equal to X" and "greater than or equal to X" (e.g., where X is a numerical value) are also disclosed. It should also be understood that throughout this application, data is provided in several different formats, and this data represents a range of endpoints and start points, and any combination of data points. For example, if a specific data point "10" and a specific data point "15" are disclosed, then it can be understood that greater than, greater than or equal to, less than, less than or equal to, and equal to 10 and 15 are considered to be between 10 and 15. It should also be understood that units between two specific units are also disclosed. For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14 are also disclosed.

[0168] Although various illustrative embodiments have been described above, any of the several modifications may be made to the various embodiments without departing from the scope of the invention as set forth in the claims. For example, in alternative embodiments, the order in which the various described method steps are performed may often be changed, and in other alternative embodiments, one or more method steps may be omitted together. Optional features of various apparatus and system embodiments may be included in some embodiments and not in others. Therefore, the description provided above is primarily for illustrative purposes and should not be construed as limiting the scope of the invention as set forth in the claims.

[0169] The examples and illustrations contained herein are intended to illustrate, and not limit, specific embodiments of the subject matter that may be practiced. As stated above, other embodiments may be applied and derived therefrom, and thus structural and logical substitutions and changes may be made without departing from the scope of this disclosure. Such embodiments of the inventive subject matter may be referred to individually or collectively herein as “inventions” for convenience only and not intended to intentionally limit the scope of this application to any single invention or inventive concept if more than one invention or inventive concept is actually disclosed. Therefore, although specific embodiments have been illustrated and described herein, the illustrated embodiments may be substituted for the predicted arrangements to achieve the same purpose. This disclosure is intended to cover all adjustments or variations of the various embodiments. Combinations of the above embodiments and other embodiments specifically described herein will be apparent to those skilled in the art upon reading the above description.

Claims

1. An apparatus for removing material from a blood vessel, the apparatus comprising: A reversing support includes a catheter having an elongated, flexible catheter body with an internal lumen communicating with an open distal end of the catheter body. The reversing support also includes an expandable funnel disposed at the distal end of the catheter body and extending along a proximal-distal axis, wherein the distal end of the funnel defines a distal opening communicating with the interior of the funnel and the lumen of the catheter, respectively, and wherein, in an open configuration, the inner wall of the funnel has a wall angle of less than 14 degrees relative to the proximal-distal axis for more than 50% of its length, and the inner wall has a first region having a wall angle between 14 and 50 degrees relative to the proximal-distal axis; and A traction device includes a flexible tube that extends distally along the outer surface of the conduit in a non-reversed configuration, reverses into the distal opening of the funnel, and extends proximally within the funnel and the conduit lumen, respectively, in a reversed configuration, wherein the flexible tube is configured to reverse by rolling over the distal opening of the funnel when a first end of the traction device is pulled proximally within the conduit lumen.

2. The apparatus of claim 1, wherein the funnel includes a mesh forming the inner wall of the funnel, wherein the mesh is reversed at the distal opening of the funnel and forms the outer wall of the funnel.

3. The device of claim 2, wherein the outer wall has a wall angle of less than 14 degrees relative to the proximal-distal axis.

4. The device of claim 2 or 3, wherein the funnel includes a plurality of longitudinal branches that are continuous with the conduit body near the funnel and are disposed between the inner wall and the outer wall.

5. The device according to any one of claims 1-3, wherein the inner wall further comprises a second region having a wall angle between 14 and 50 degrees relative to the proximal-distal axis, wherein the second region is separated from the first region by an intermediate region having a wall angle of less than 14 degrees relative to the proximal-distal axis.

6. The device of any one of claims 1-3, wherein at least a portion of the inner wall having a wall angle of less than 14 degrees relative to the proximal-distal axis has a negative wall angle relative to the proximal-distal axis, such that the inner wall narrows from the proximal to the distal direction.

7. The device of any one of claims 1-3, wherein at least the base region of the funnel adjacent to the distal end of the conduit body includes a plurality of openings configured to allow fluid to pass through it.

8. The apparatus of claim 7, wherein the base region includes a circumferentially porous region.

9. The device according to any one of claims 1-3, wherein the funnel has a converging configuration, the maximum outer diameter of the converging configuration being less than 0.3 times the outer diameter of the conduit body near the funnel.

10. The device according to any one of claims 1-3, wherein in the open configuration, the minimum outer diameter of the funnel is greater than 1.5 times the outer diameter of the conduit body near the funnel.

11. The apparatus of claim 10, wherein in the open configuration the funnel has an outer diameter between 2 mm and 26 mm.

12. The apparatus of any one of claims 1-3, wherein the flexible tube comprises a knitted tube.

13. The device of claim 1, wherein the funnel is configured to open from a closed configuration to the open configuration when the flexible tube is pulled proximally into the lumen of the conduit and an axial compressive force is applied to the distal end of the funnel.

14. The apparatus of claim 13, wherein the funnel is held in a squeezed state in the open configuration when the flexible tube is pulled proximally into the lumen of the catheter, and wherein the funnel has greater column strength in the squeezed state compared to when the funnel is not in the squeezed state.

15. The apparatus of claim 14, wherein in the squeezed state, the funnel is configured to withstand a compressive force greater than 11 Newtons without collapsing.

16. The apparatus of any one of claims 1-3, further comprising a pull rod disposed within the lumen of the catheter, wherein a first end of the traction device is coupled to the pull rod.

17. The apparatus of claim 1, wherein the inner wall of the funnel includes one or more narrowing regions in which the inner wall of the funnel narrows from the proximal side to the distal side.

Images