Catheter with increased tensile strength

Abstract

The neurovascular catheter has increased tensile strength to resist dislodgement of the distal tip when retracted proximally over an obstruction. The catheter includes an elongated flexible tubular body having a proximal end, a distal end, and a sidewall defining a central lumen. A radiopaque marker is disposed adjacent to the distal end. A tensile support extends axially within the sidewall and is attached to the radiopaque marker to anchor the marker to the catheter body. In one implementation, the tensile support may at least partially wrap around the marker. The marker may have a tubular sidewall that may be provided with a feature for increasing compressibility, such as at least one compressible gap, in a proximal portion of the sidewall.

Description

Technical Field

[0001] Cross - reference to Related Applications This application is a continuation - in - part of U.S. Patent Application No. 17 / 343,004, filed on June 9, 2021, which claims the priority of U.S. Provisional Patent Application No. 63 / 064,270, filed on August 11, 2020, under 35 U.S.C. § 119(e). The entire content of each document is incorporated herein by reference.

Background Art

[0002] Stroke is the third leading cause of death in the United States and the most disabling neurological disorder. Approximately 700,000 patients suffer from stroke each year. Stroke is a syndrome characterized by the acute onset of neurological deficits that persist for at least 24 hours, reflecting focal complications of the central nervous system and resulting from disturbances in cerebral circulation. The incidence increases with age. Risk factors for stroke include systolic or diastolic hypertension, hypercholesterolemia, smoking, heavy alcohol consumption, and use of oral contraceptives.

[0003] Hemorrhagic stroke accounts for 20% of the annual stroke population. Hemorrhagic stroke often occurs when an aneurysm or arteriovenous malformation ruptures and bleeds into the brain tissue, resulting in a cerebral infarction. The remaining 80% of the stroke population are ischemic strokes, which occur when blood carrying oxygen is deprived from the brain due to vessel occlusion. Ischemic strokes often occur when embolic or thrombotic tissue fragments break off from other sites or from the cerebral blood vessels themselves and occlude narrower distal cerebral arteries. When a patient presents neurological symptoms and signs that completely resolve within one hour, the term transient ischemic attack (TIA) is used. Etiologically, TIA and stroke share the same pathophysiological mechanisms and thus represent a continuum of conditions based on the duration of symptoms and the extent of ischemic injury.

[0004] Embolisms can form around the heart valves or in the left atrial appendage during irregular heartbeats, and then detach and travel through the bloodstream to distal parts of the body. These emboli can reach the brain and cause embolic stroke. As will be discussed later, many such occlusions occur in the middle cerebral artery (MCA), but this is not the only site where emboli can occur.

[0005] When a patient presents with neurological deficits, a diagnostic hypothesis regarding the cause of stroke can be formulated based on the patient's medical history, consideration of stroke risk factors, and neurological examination. If an ischemic event is suspected, the clinician can tentatively assess whether the patient has a cardiogenic embolic source, extracranial or intracranial disease of the aorta, intraparenchymal disease of the arterioles, or alternatively, hematological or other systemic disease. A head CT scan is often performed to determine whether the patient has suffered ischemic or hemorrhagic injury. Blood will be present on the CT scan in cases of subarachnoid hemorrhage, intracortical hematoma, or intraventricular hemorrhage.

[0006] In the context of ischemic stroke, a wide variety of thrombectomy devices have been developed to capture and retrieve thrombi. These include catheters or wires carrying various expandable cages, baskets, snares, drug or energy carriers, and suction with or without mechanical destructive force. Each catheter may be required to be maneuvered to deep parts of the vascular system, such as the distal ophthalmic artery. Maneuverability issues can limit the ability of many catheters to successfully reach obstacles. Furthermore, when retracting the catheter proximal, the marker band may become entangled with the occlusion, potentially leading to tip detachment.

[0007] Despite the above, there is still a need for new devices and methods for treating intravascular occlusion, including acute ischemic stroke and obstructive cerebrovascular disease, that have improved maneuverability to traverse winding vascular systems and reach remote treatment sites, and / or improved tensile strength to reduce the risk of tip detachment. [Overview of the project]

[0008] According to one aspect of the present invention, a neurovascular catheter is provided having a pre-formed distal tip for self-orientation with respect to the natural curvature of a vessel, in order to improve transvascular maneuverability through a winding distal vascular system. The catheter comprises a long, flexible tubular body having a proximal end, an inclined distal end, and a side wall defining a central lumen. The distal tip is supported on the first side of the inclined distal end, and a pre-set curve is provided in the distal zone of the tubular body. The distal tip is located on the concave side of the curve.

[0009] A tubular radiopaque marker may be embedded within the side wall, and the tubular radiopaque marker includes a proximal surface and a distal surface, the distal surface of the radiopaque marker being inclined at an angle within the range of approximately 45 to 80 degrees with respect to the longitudinal axis of the central lumen.

[0010] The central lumen is terminated distally by a distal port having an elliptical opening, and the elliptical opening may have an area that is at least about 105% or at least about 110% of the cross-sectional area of ​​the central lumen, and generally in the range of about 110% to about 125%.

[0011] The elliptical opening defines an inclined distal surface that is tilted at an angle of approximately 55 to 65 degrees with respect to the longitudinal axis of the central lumen.

[0012] The distal surface of the radiopaque marker may also be inclined at an angle within the range of approximately 55 to 65 degrees with respect to the longitudinal axis of the central lumen. The proximal surface on the radiopaque marker may be approximately perpendicular to the longitudinal axis.

[0013] The distal end of the catheter may be spaced apart from the distal surface of the radiopaque marker, thereby forming an advancing segment of the tube. The advancing segment may have an axial length in the range of approximately 0.1 mm to approximately 5 mm. The axial length of the advancing segment on the anterior edge side of the tube may be greater than the axial length of the advancing segment on the posterior edge side of the tube. The axial length of the advancing segment on the anterior edge side of the tube may be at least approximately 20% longer than the axial length of the advancing segment on the posterior edge side of the tube.

[0014] The radiopaque marker may have at least one axial slit.

[0015] The catheter may further include support filaments to increase tensile resistance in the distal zone and / or to influence bending properties in the distal zone. The support filaments may include axially extended filaments that can be carried between the inner liner and the helical coil and may be positioned on the convex side of a predetermined curve. In one implementation, the axially extended filaments may include Vectran.

[0016] According to another aspect of the present invention, a self-orienting catheter is provided. The catheter comprises a long, flexible tubular body having a proximal end, a distal zone, and a side wall defining a central lumen. A tubular radiopaque marker band may be embedded in the side wall in the distal zone. The radiopaque marker band may have a first axial length measured along the side wall at a first circumferential position and a longer second axial length measured along the side wall at a second circumferential position offset about 180 degrees around the circumferential direction of the catheter from the first position, and the tubular body may have a preset curve in the distal zone. The preset curve has a concave side and a convex side, and the longer second axial length of the marker may be located on the concave side of the curve. An axially extended filament may be positioned on the convex side.

[0017] Furthermore, catheters such as neurovascular catheters with enhanced tensile strength are provided, which include a long, flexible tubular body having a proximal end, a distal end, and a side wall defining a central lumen; a radiopaque marker adjacent to the distal end and extending over at least a portion of the outer circumference of the tubular body; and a tension support extending axially within the side wall. The tension support is attached to the marker, thereby anchoring the marker to the catheter body, thereby resisting detachment of the distal end when retracting proximal over an obstacle. In one implementation, the tension support may extend distally along a first side (e.g., the inside) of the radiopaque marker, may be folded back around the distal edge of the radiopaque marker, and may also extend along a second side (e.g., the outside) of the radiopaque marker.

[0018] The tension support may include multiple fibers, in one example, a Vectran multifilament liquid crystal polymer fiber. The tension support may extend circumferentially around the marker over at least about 180 degrees, or over 360 degrees, or beyond. The sidewall of the catheter may include an inner liner, a binding layer, and a helical coil, with the tension support extending axially between the helical coil and the inner liner. The sidewall may include an outer jacket having multiple tubular segments, the proximal tubular segments of which have a durometer of at least about 60 D, and the distal tubular segments of which have a durometer of up to about 35 D.

[0019] The radiopaque marker may include a proximal and a distal surface, the distal surface may be inclined at an angle in the range of approximately 45 to 80 degrees with respect to the longitudinal axis of the central lumen. The radiopaque marker may also include an annular ring having at least one axial slit.

[0020] The catheter may include an inclined distal surface with a distal port having an elliptical opening, the elliptical opening may have an area that is at least about 105% of the transverse cross-sectional area of ​​the central lumen. The area of ​​the elliptical opening may be at least about 110% of the cross-sectional area of ​​the central lumen, and the elliptical opening may be located on a plane inclined at an angle in the range of about 55 to about 65 degrees with respect to the longitudinal axis of the central lumen.

[0021] The proximal surface of the radiopaque marker may be approximately perpendicular to the longitudinal axis. The distal end of the catheter may be spaced apart from the distal surface of the radiopaque marker, thereby forming an advancing segment of the tube body beyond the distal end of the marker. The advancing segment may have an axial length in the range of approximately 0.1 mm to approximately 5 mm. The axial length of the advancing segment on the anterior edge side of the tube body may be greater than the axial length of the advancing segment on the posterior edge side of the tube body.

[0022] In catheters having an outer diameter of about 0.10 inches (about 0.254 cm) or less or about 0.080 inches (about 0.2032 cm) or less, in some implementations, they may be configured to withstand at least about 1.5 pounds or at least about 3.5 pounds of tension before breakage (tip detachment), and in some cases, to withstand at least about 5 pounds of tension before breakage or at least about 7 pounds of tension before breakage. In any of the neurovascular catheters described herein, the radiopaque marker may include a tubular sidewall having a proximal end and a distal end, and at least one compression mechanism for increasing the compressibility of the proximal end. The compression mechanism may include at least one compression gap in the sidewall, and the at least one compression gap may open at the proximal end of the sidewall and extend distally. Alternatively, the compression mechanism may include a plurality of struts joined at their vertices, thereby forming a crushable tubular sidewall attached to a coil or other catheter component. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] [Figure 1A] FIG. 1A is a side view showing a catheter according to the present invention. [Figure 1B] FIG. 1B is a side view showing a catheter having a preformed curve according to the present invention. [Figure 1C] FIG. 1C is an enlarged view showing the distal portion of the catheter of FIG. 1. [Figure 1D] FIG. 1D is another enlarged view showing the distal portion of the catheter of FIG. 1. [Figure 2] FIG. 2 shows a cross-sectional view of a catheter wall according to another embodiment. [Figure 3A] FIG. 3A shows a cross-sectional view of a catheter wall according to another embodiment, illustrating one or more axially extending tension members. [Figure 3B] FIG. 3B illustrates a side view of the catheter of FIG. 3A. [Figure 3C]Figure 3C shows a cross-sectional view along the C-C line in Figure 3B, and illustrates one or more axially extending tension members. [Figure 3D] Figure 3D is a side cross-sectional view through the angled distal catheter or through the tip of the extension tube. [Figure 3E] Figure 3E shows a tip like that of Figure 3D with a tethered marker band. [Figure 4A] Figure 4A is a side view showing the marker band. [Figure 4B] Figure 4B is a side view showing the marker band. [Figure 4C] Figure 4C is a plan view showing the marker band of Figure 4B. [Figure 4D] Figure 4D is a side view showing an alternative marker band. [Figure 4E] Figure 4E is a side view showing an alternative marker band having an integral tubular tension member. [Figure 4F] Figure 4F is a side view showing an alternative marker band. [Figure 4G] Figure 4G is a perspective view from the side showing the alternative marker band of Figure 4F. [Figure 4H] Figure 4H is a side view showing an alternative marker band. [Figure 4I] Figure 4I is a perspective view from the side showing the alternative marker band of the figure. [Figure 5A] Figure 5A shows a side view of a catheter with gradually enhanced flexibility according to one embodiment. [Figure 5B] Figure 5B is a proximal end view showing the catheter with enhanced flexibility in Figure 5A.

Best Mode for Carrying Out the Invention

[0024] Referring to Figures 1A to 1C, a catheter 10 according to one aspect of the present invention is disclosed. Although primarily described in the context of a suction catheter having a single central lumen, the catheter of the present invention can be readily modified to incorporate additional structures, such as a permanent or removable column strength-enhancing mandrel, or alternatively, two or more lumens, such as one for enabling the injection of drugs, contrast agents, or irrigation fluids, or for supplying an inflation medium to one or more inflatable balloons supported by the catheter, or alternatively, a combination of these features, which will be readily apparent to those skilled in the art in light of the disclosure herein. In addition, although primarily described in the context of removing occlusive material from the distant vascular system in the brain, the present invention has applicability as an access catheter for delivering or removing any of a variety of diagnostic or therapeutic devices, with or without suction.

[0025] The catheters disclosed herein can be easily configured for use anywhere in the body where it is desirable to advance a low-bulk, highly flexible catheter distally into small and / or winding vascular systems. For example, the catheter shaft according to the present invention may be sized to be suitable for use anywhere in the coronary arteries and peripheral vascular systems, the gastrointestinal tract, urethra, ureters, fallopian tubes, and other lumens, and any conceivable lumens. The catheter shaft structures of the present invention may also be used to provide minimally invasive percutaneous tissue access, for example, diagnostic or therapeutic access to solid tissue targets (e.g., biopsy or tissue resection of the breast, liver, or brain), alternatively, access for the delivery of laparoscopic instruments, or alternatively, access to bone such as the spine for the delivery of screws, bone cement, or other instruments or implants.

[0026] The catheter 10 generally includes a long tubular body 16 extending between a proximal end 12 and a distal functional end 14. The catheter 10 may or may not have a pre-set curve (Figure 1A), or it may have a pre-set curve (Figures 1B-1C). The length of the tubular body 16 depends on the desired application. For example, lengths ranging from approximately 120 cm to approximately 140 cm, or beyond, are typical for use in percutaneous transluminal coronary artery applications via femoral access. In intracranial or other applications, different catheter shaft lengths may be required depending on the vascular access site, as will be described in more detail below.

[0027] The catheter according to the present invention will have a length and diameter suitable for the intended access point and target location. For example, referring to Figures 1A to 1C, the effective length of the catheter 10 from the manifold or hub 20 to the distal tip 22 may generally be about 180 cm or less, or about 160 cm or less, and typically about 70 cm to about 150 cm, about 90 cm to about 130 cm, or about 105 cm to about 115 cm. The outer diameter of the catheter 10 may be about 0.035 inches to about 0.15 inches (about 0.0889 cm to about 0.381 cm), or about 0.09 inches to about 0.13 inches (about 0.2286 cm to about 0.3302 cm), and the distal segment may be smaller than the proximal segment.

[0028] In the embodiment with a single central lumen, the inner diameter of the catheter 10 may be about 0.1 inches (about 0.254 cm) or more, about 0.088 inches (about 0.22352 cm) or more, about 0.08 inches (about 0.2032 cm) or more, or about 0.06 cm or more. In the embodiment with a single central lumen, the inner diameter of the catheter 10 may be less than about 0.20 inches (about 0.508 cm) or less than 0.15 inches (about 0.381 cm), and alternatively, it may be about 0.11 inches (about 0.2794 cm) or less, about 0.1 inches (about 0.254 cm) or less, about 0.088 inches (about 0.22352 cm) or less, or about 0.07 inches (about 0.1778 cm) or less, and in many cases, it may be about 0.095 inches (about 0.2413 cm) or less.

[0029] Figure 1C shows the distal portion of the tube body 16. The passive distal steering zone 18 on the tube body 16 is provided with a preformed curve having a concave side 26 and a convex side 28. The tube body 16 is also provided with an inclined surface 31, which will be described in more detail in relation to Figure 3D. The inclined surface 31 forms a leading edge at the distal tip 22 and a trailing edge 24 on the opposite side of this leading edge. The leading edge 22 is positioned on the concave side 26 of the preformed curve.

[0030] In an unconstrained configuration, the preformed curve establishes an angle A between the longitudinal axis of the tube body 16 at the proximal side of the curve (i.e., the concave side of the preformed curve) and the longitudinal axis formed by the most distal 2 mm or 3 mm portion of the tube body 16. Angle A is generally in the range of about 25° to about 55°, preferably about 50° or less, and in some implementations, about 30° to about 40°. Angle A is preferably in the range of about 32° to about 38°, and in one example, about 35°. Additionally, in some implementations, angle A is in the range of about 25° to about 45°, about 20° to about 45°, about 15° to about 55°, or about 15° to about 50°. This angle, combined with a small lateral bias of a pre-set curve, is small enough to allow the catheter tip 22 to follow the natural vascular system, and also small enough not to penetrate the side wall and exit into the extravascular space.

[0031] In some embodiments, as shown in Figure 1D, the preformed curve establishes an angle B between the longitudinal axis of the tube body 16 at the proximal side of the curve (e.g., at the transition 30, or at the convex side of the preformed curve, or based on the proximal edge of the marker band) and the distal tip 22. Angle B is generally in the range of about 25° to about 55°, preferably about 50° or less, and in some implementations it is about 25° to about 35°. Angle A is preferably in the range of about 27° to about 33°, and in one example it is about 30°. Additionally, in some implementations, angle B is in the range of about 25° to about 45°, about 20° to about 45°, about 15° to about 55°, or about 15° to about 50°.

[0032] In some embodiments, as further shown in Figure 1, the preformed curve establishes a height H between the longitudinal axis of the tube body 16 at the proximal side of the curve (e.g., at the transition 30, or at the convex side of the preformed curve, or based on the proximal edge of the marker band) and the distal tip 22. The height H is generally in the range of about 0.25 cm to about 0.6 cm, and in some implementations, it is in the range of about 0.3 cm to about 0.4 cm, or about 0.35 cm to about 0.45 cm, or about 0.4 cm to about 0.5 cm, or about 0.45 cm to about 0.55 cm.

[0033] The lateral limit of deflection D in an unconstrained state is generally in the range of approximately 0.1 inches to approximately 0.2 inches (approximately 0.254 cm to approximately 0.508 cm), and in one embodiment, approximately 0.15 inches (approximately 0.381 cm). In some implementations, the deflection D in an unconstrained state is generally in the range of approximately 0.05 inches to approximately 0.15 inches (approximately 0.127 cm to approximately 0.381 cm), approximately 0.06 inches to approximately 0.13 inches (approximately 0.1524 cm to approximately 0.3302 cm), approximately 0.07 inches to approximately 0.12 inches (approximately 0.1778 cm to approximately 0.3048 cm), approximately 0.075 inches to approximately 0.12 inches (approximately 0.1905 cm to approximately 0.3048 cm), etc. In an unconstrained state, the deflection D is typically less than or equal to approximately 0.3 inches (approximately 0.762 cm), or less than or equal to approximately 0.25 inches (approximately 0.635 cm), or less than or equal to approximately 0.2 inches (approximately 0.508 cm), depending on the catheter diameter.

[0034] The tube body 16 includes a transition section 30 at the proximal limit of the preformed curve. The arc length of the preformed curve, measured from the transition section 30 to the distal tip 22, is generally less than approximately 2 cm, or less than approximately 1.5 cm, or less than approximately 1 cm, and is often between approximately 0.5 cm and 1.5 cm, with some implementations being between approximately 1.1 cm and 1.4 cm. In some implementations, the arc length is in the range of approximately 0.75 cm to 1.75 cm, or approximately 0.5 cm to 2 cm, or approximately 1.25 cm to 2 cm.

[0035] The tube body 16 of the present invention is sufficiently flexible so that the catheter can follow along, allowing it to easily advance even through narrow and / or winding body passages. The catheter may bend in any plane in three-dimensional space in response to its advancement through curves in the vascular system. Thus, the pre-formed curve, at least distally, may spontaneously twist around the longitudinal axis of the catheter as it advances through the body passage so that it itself is oriented to conform to the configuration at the lowest energy state through the curvature of the vessel. The torque transmission through the tube body 16 is sufficiently small (low torsional rigidity) so that the distal end of the catheter can twist around the axis as desired in both clockwise and counterclockwise directions, thereby allowing it to self-orient with respect to the vascular system during distal advancement without the need to rotate the proximal end of the catheter. In some embodiments, the distal end of the catheter can be twisted by at least about 10 degrees and at least about 20 degrees in any direction without requiring any rotation of the proximal end of the catheter, or in some embodiments, it can be twisted by at least about 45 degrees, or 90 degrees, or more. The self-orientation or twisting of the catheter may optimize the interaction angle of the distal end of the catheter with respect to the blood clot, thereby improving or maximizing the uptake of the blood clot.

[0036] Figure 2 shows a cross-section formed through the side wall of the distal portion of a single-lumen catheter, with or without a predetermined curve. The adjacent loops or fillers formed by the coil 3024 may have a constant pitch over the entire length of the coil, or alternatively, they may be tightly wound in the proximal zone and the spacing between adjacent loops may be looser in the distal portion. In embodiments having a coil portion 3024 with an axial length of about 20% to about 30% of the total length of the catheter (for example, a 110 cm catheter shaft 16 with a coil length of 28 cm), at least about 1 cm, or about 2 cm, or about 3 cm, or about 4 cm of the distal portion of the coil will have spacings of at least about 130%, and in some implementations at least about 150% or more, compared to the spacing in the proximal coil portion. In a 110 cm catheter shaft 3000 with Nitinol® coils, the spacing at the proximal coil may be approximately 0.004 inches (approximately 0.01016 cm), and at the distal portion, the spacing may be at least approximately 0.006 inches (approximately 0.01524 cm), or 0.007 inches (approximately 0.01778 cm), or greater.

[0037] The distal end of the coil 3024 can be spaced proximal to the distal end of the inner liner 3014, thereby providing space for the annular radiopaque marker 3040. In some embodiments, the coil 3024 may be retracted proximal to the distal end by approximately 1 cm or less, 2 cm or less, or 3 cm or less. In one embodiment, the distal end of the catheter 10 is provided with an inclined distal surface 3006 that lies on a plane having an angle of at least approximately 10° or approximately 20° with respect to the longitudinal axis of the catheter 10, and in one embodiment, on a plane having an angle of approximately 30°. The radiopaque marker 3040 may lies in a plane transverse to the longitudinal axis. Alternatively, at least the distal end of the annular radiopaque marker 3040 may be elliptical, lies on a plane that is inclined with respect to the longitudinal axis and is complementary to the inclination angle of the distal surface 3006. Further details will be explained in relation to Figure 3D below.

[0038] After applying the proximal braid 3010, distal coil 3024, and RO marker 3040 onto the binding layer 3012, an outer jacket 3020, such as a shrink wrap tube, is provided to surround the catheter body 16. The outer shrink wrap sleeve 3020 may contain any variety of materials, such as polyethylene, polyurethane, polyether block amide (e.g., PEBAX®), nylon®, or other materials known in the art. By applying sufficient heat, the polymer flows into and embeds itself within the proximal braid and distal coil.

[0039] In one implementation, the outer shrink wrap jacket 3020 is formed by sequentially advancing a plurality of short tubular segments 3022, 3026, 3028, 3030, 3032, 3034, 3036, and 3038 concentrically across the catheter shaft subassembly and applying heat to shrink these segments onto the catheter 10, thereby providing a smooth, continuous outer tubular body. The segmented structure may extend along at least the most distal 10 cm of the catheter body 10, preferably along at least about 20 cm, about 25 cm, about 30 cm, about 35 cm, about 40 cm, or more than about 40 cm from the most distal end. The entire length of the outer shrink wrap jacket 3020 may be formed from tubular segments, and the length of the distal tubular segments (e.g., 3022, 3026, 3028, 3030, 3032, 3034, 3036, 3038) may be shorter than one or more tubular segments forming the proximal portion of the outer shrink wrap jacket 3020 in order to provide a steep transition in proximal backup support and flexibility toward the distal end of the catheter 10.

[0040] The durometer of the outer wall segments may decrease distally. For example, proximal segments such as 3022 and 3026 may have a durometer of at least about 60D or about 70D, and the durometer of the sequential segments gradually decreases distally to about 35D or about 25D or less. The 25cm portion may have at least about 3, about 5, about 7, or more segments, and the entire catheter 10 may have at least about 6, about 8, about 10, or more distinctly different flexible zones. The distal segments 3036, 3038, which number one, two, four, or more, may have a smaller post-contraction OD compared to the more proximal segments 3022-3034, thereby forming a decrease in OD relative to the completed catheter body 16. The length of the smaller OD portion 3004 may be in the range of about 3 cm to about 15 cm, and in some embodiments, in the range of about 5 cm to about 10 cm, for example, about 7 cm or about 8 cm, which may be achieved by making the distal segments 3036, 3038 thinner.

[0041] In another embodiment, the distal portion of the catheter 10 may include a durometer of less than about 35D (e.g., 25D) to form the highly flexible distal portion of the catheter, and may have a length of about 25 cm to about 35 cm. The distal portion may include one or more tubular segments (e.g., segment 3038) of the same durometer. A series of adjacent tubular segments on the proximal side may form a transitional region between the rigid proximal portion and the highly flexible distal portion of the catheter 3000. The series of tubular segments forming the transitional region may have the same length, or may have substantially similar lengths, such as about 1 cm.

[0042] Each of the series of tubular segments is relatively short in length, which may cause a steep decrease in durometer across the transition region. For example, the transition region may have a proximal tubular segment 3036 (proximal to the distal portion) with a durometer of approximately 35 D. The adjacent proximal segment 3034 may have a durometer of approximately 55 D. The adjacent proximal segment 3032 may have a durometer of approximately 63 D. The adjacent proximal segment 3030 may have a durometer of approximately 72 D.

[0043] The more proximal segments may include a durometer greater than approximately 72D and may extend to the proximal end of the catheter or extension catheter segment. For example, the extension catheter segment may include a proximal portion greater than approximately 72D over a period of approximately 1 cm to approximately 3 cm. In some embodiments, the proximal portion may be about 2 cm in length. In some embodiments, the most distal segments (e.g., 3038-3030) may include PEBAX®, and the more proximal segments may include a generally rigid material such as Vestamid®.

[0044] The inner diameter of the catheter 10 may be approximately 0.06 inches to 0.08 inches (approximately 0.1524 cm to 0.2032 cm), approximately 0.065 inches to 0.075 inches (approximately 0.1651 cm to 0.1905 cm), or approximately 0.068 inches to 0.073 inches (approximately 0.17272 cm to 0.18542 cm). In some embodiments, the inner diameter is approximately 0.071 inches (approximately 0.18034 cm).

[0045] In some embodiments, the distal portion may taper in diameter, as described elsewhere in this specification. This taper may occur substantially between the distal highly flexible portion and the transition region (for example, over the most proximal portion of the distal highly flexible portion). The taper may be relatively gentle (e.g., it may occur over about 10 cm or more), or alternatively, relatively steep (e.g., it may occur over less than about 5 cm). The diameter may taper to a diameter of about 0.03 inches to about 0.06 inches (about 0.0762 cm to about 0.1524 cm). For example, the diameter at the distal end of catheter 3000 may be about 0.035 inches (about 0.0889 cm), about 0.045 inches (about 0.1143 cm), or about 0.055 inches (about 0.1397 cm). In some embodiments, the inner diameter may remain constant, at least over the catheter extension segment.

[0046] In some embodiments, the coil 3024 may extend proximal from the distal end of the catheter 10 along a highly flexible distal portion and terminate at the distal end of the transition region. In other embodiments, the coil 3024 may extend from the distal end of the catheter to the proximal end of the transition region, or to a point along the transition region, or proximal beyond the transition region. In other embodiments, the coil 3024 may extend along the entire length of the catheter 10 or the catheter extension segment, as described elsewhere in this specification. The braid 3010, if present, may extend from the proximal end of the coil 3024 to the proximal end of the catheter 10.

[0047] Referring to Figures 3A to 3D, the catheter may further include axial tension members or axial supports, such as ribbons, one or more filaments, or one or more fibers, to increase tensile resistance in the distal zone and / or to influence the bending properties in the distal zone. The tension supports may include one or more axially extended monostrand or multistrand filaments 3042. One or more tension members 3042 may be axially positioned inside the catheter wall near the distal end of the catheter. The filaments may be positioned on the convex side of the catheter having a predetermined curve. One or more tension members 3042 may also function as tension supports under tension (for example, when the catheter retracts proximal through a winding or narrowed vascular system) and may resist stretching of the catheter wall.

[0048] At least one of the one or more tension members 3042 may extend proximal along the length of the catheter wall from within about 1.0 cm from the distal end of the catheter to less than about 10 cm from the distal end of the catheter, less than about 20 cm from the distal end of the catheter, less than about 30 cm from the distal end of the catheter, less than about 40 cm from the distal end of the catheter, or less than about 50 cm from the distal end of the catheter.

[0049] One or more tension members 3042 may have a length of approximately 40 cm or more, approximately 30 cm or more, approximately 20 cm or more, approximately 10 cm or more, or approximately 5 cm or more.

[0050] At least one of the one or more tension members 3042 may extend over at least about 50 cm of the distal end of the catheter length, over at least about 40 cm of the distal end of the catheter length, over at least about 30 cm, at least about 20 cm, or at least about 10 cm of the distal end of the catheter length.

[0051] In some implementations, the tension member extends proximal to the distal end of the catheter along the length of the coil 24, and terminates proximal to either side of the transition 3011 between the coil 3024 and the braid 3010, within a range of approximately 5 cm, approximately 2 cm, or less. The tension member may terminate at the transition 3011 without overlapping with the braid 3010.

[0052] One or more tension members 3042 may be positioned near or radially outward of the binding layer 3012 or the inner liner 3014. One or more tension members 3042 may be positioned near or radially inward of the braid 3010 and / or the coil 3024. One or more tension members 3042 may be supported between the inner liner 3014 and the helical coil 3024, and may also be fixed to the inner liner or other substrate with adhesive before adding subsequent outer adjacent layers such as coils.

[0053] If two or more tension members 3042 or filament bundles are spaced apart circumferentially within the catheter wall, the tension members 3042 may be arranged in a radially symmetrical manner. For example, the angle between two filaments 3042 with respect to the radial center of the catheter may be about 180 degrees. Alternatively, depending on the desired clinical performance (e.g., flexibility, conformability), the tension members 3042 may be arranged in a radially asymmetrical manner. The angle between two tension members 3042 with respect to the radial center of the catheter may be less than about 180 degrees, about 165 degrees or less, about 135 degrees or less, about 120 degrees or less, about 90 degrees or less, about 45 degrees or less, or about 15 degrees or less.

[0054] One or more tension members 3042 may include materials such as Vectran, Kevlar, polyester, meta-para-aramid, or any combination thereof. At least one of the one or more tension members 3042 may include a single fiber or a bundle of multiple fibers, and the fiber or bundle may have a circular or rectangular (e.g., ribbon) cross-sectional shape. The terms fiber or filament do not indicate composition and may include any of various high-tensile polymers, metals, or alloys depending on design considerations, for example, depending on the desired tensile fracture limit and wall thickness. The cross-sectional dimensions of one or more tension members 3042, measured radially, may be approximately 2% or less, 5% or less, 8% or less, 15% or less, or 20% or less compared to the cross-sectional dimensions of the catheter 10.

[0055] The cross-sectional dimensions of one or more tension members 3042, when measured radially, may be approximately 0.001 inches (approximately 0.00254 cm) or less, approximately 0.002 inches (approximately 0.00508 cm) or less, approximately 0.004 inches (approximately 0.01016 cm) or less, approximately 0.006 inches (approximately 0.01524 cm) or less, approximately 0.008 inches (approximately 0.02032 cm) or less, or approximately 0.015 inches (approximately 0.0381 cm) or less.

[0056] One or more tensioning members 3042 may increase the tensile strength in the distal zone of the catheter before breakage under tension to at least about 1 pound, at least about 2 pounds, at least about 3 pounds, at least about 4 pounds, at least about 5 pounds, at least about 6 pounds, at least about 7 pounds, at least about 8 pounds, or at least about 10 pounds, or more.

[0057] Any catheter disclosed herein may have an angled distal tip, regardless of whether or not it includes an axial tension member. Referring to Figure 3D, the distal catheter tip 3110 includes a tubular body 3112, which includes an advancing segment 3114, a marker band 3116, and a proximal segment 3118. An inner tubular liner 3120 may extend over the entire length of the distal catheter tip 3110 and may include dipped-coated PTFE.

[0058] A reinforcing member 3122, such as a braid or spring coil, is embedded within an outer jacket 3124 that may extend along the entire length of the distal catheter tip 3110.

[0059] The forward segment 3114 terminates distally within the inclined surface 3126, thereby providing a leading sidewall portion 3128 having a length measured between the distal end 3130 and the distal tip 3132 of the marker band 3116. In the illustrated embodiment, the trailing sidewall portion 3134 of the forward segment 3114 has an axial length approximately equal to the axial length of the leading sidewall portion 3128, measured at approximately 180 degrees around the catheter from the leading sidewall portion 3128. The leading sidewall portion 3128 may have an axial length in the range of approximately 0.1 mm to approximately 5 mm, and generally in the range of approximately 1 mm to 3 mm. Depending on the desired performance, the trailing sidewall portion 3134 may be at least approximately 0.1 mm, 0.5 mm, 1 mm, 2 mm, or more shorter than the axial length of the leading sidewall portion 3128.

[0060] The inclined surface 3126 is inclined at an angle A, which is set to be in the range of approximately 45 to 80 degrees from the longitudinal axis of the catheter. In certain implementations, this angle is in the range of approximately 55 to 65 degrees from the longitudinal axis of the catheter, or in the range of approximately 55 to 65 degrees. In one implementation, angle A is approximately 60 degrees. One consequence of angle A being less than approximately 90 degrees is an extension of the long axis in the area made up of the distal port, which can increase the surface area of ​​the port and enhance the aspiration or retention of blood clots. Compared to the surface area of ​​a round port (when angle A is 90 degrees), the area of ​​an inclined port is generally at least approximately 105% and no more than approximately 130%, in some implementations it is in the range of approximately 110% to approximately 125%, and in one example it is approximately 115%.

[0061] In the illustrated embodiment, the axial length of the forward segment is substantially constant around the circumferential direction of the catheter, so that the inclined surface 3126 is substantially parallel to the distal surface 3136 of the marker band 3116. The marker band 3116 has a proximal surface that is substantially transverse with respect to the longitudinal axis of the catheter, so that the marker band 3116 has a right-angle trapezoidal configuration in a side view. The short side wall 3138 is rotationally aligned with the subsequent side wall portion 3134 and has an axial length in the range of approximately 0.2 mm to approximately 4 mm, typically in the range of approximately 0.5 mm to approximately 2 mm. The longer side wall 3140 located on the opposite side is rotationally aligned with the leading side wall portion 3128. The longer sidewall 3140 of the marker band 3116 is generally at least approximately 10% or 20% longer than the shorter sidewall 3138, and may be at least approximately 50%, 70%, 90%, or more longer than the shorter sidewall portion 3138, depending on the desired performance. Generally, the longer sidewall 3140 will have a length of at least approximately 0.5 mm or 1 mm, and less than approximately 5 mm or less than 4 mm.

[0062] Any of the marker bands described herein may be a continuous annular structure, or optionally have at least one, and optionally two, three, or more, axially extending slits 3117 along their entire length. The slits may be located on the shorter sidewall 3138, on the longer sidewall 3140, or between them, depending on the desired bending properties. Any of the marker bands described herein may contain any variety of radiopaque materials, such as a platinum / iridium alloy, preferably having a wall thickness of about 0.003 inches (about 0.00762 cm) or less, and about 0.001 inches (about 0.00254 cm) in a single implementation. In a single implementation, at least one axial slit is aligned with the convex side of a predetermined curve, and the filament extends distally beyond the proximal surface of the marker into the axial slit.

[0063] The marker band zone of the assembled catheter may have relatively high flexural stiffness and relatively high crushing strength, such that it is at least about 50% smaller or at least about 100% smaller than the proximal segment 18, and generally about 200% or less smaller than the proximal segment 3118. High crushing strength can provide radial support to the adjacent forward segment 3114, particularly to the leading sidewall portion 3128, thereby facilitating the distal tip 3132 to function as a non-traumatic buffer during catheter advancement and to resist collapse under vacuum. The proximal segment 3118 preferably has lower flexural stiffness compared to the marker band zone, and the forward segment 3114 preferably has even lower flexural stiffness and crushing strength compared to the proximal segment 3118.

[0064] The forward segment 3114 may include a distal extension with respect to the outer jacket 3124 and optionally with respect to the inner liner 3120, without having any other internal support structure distal to the marker band 3116. The outer jacket may include extruded Tecothane. The forward segment 3114 may have bending stiffness and radial crushing stiffness that are about 50% or less compared to the corresponding values ​​with respect to the proximal segment 3118, and in some implementations, about 25% or less, or 15% or less, or 5% or less, or less.

[0065] A tension member 3142 having the dimensions and materials described elsewhere in this specification extends through at least the distal portion of the length of the proximal segment 3118. As shown, the tension member 3142 may terminate distally at the proximal face of the marker band 3116, and may extend axially outward radially from the tubular liner 3120 and radially inward from the support coil 3122. Alternatively, the marker band may be provided with at least one or two axially extending slits 3117, through which the fiber can extend and thereby axially overlap with respect to the marker band. The tension member 3142 may extend substantially parallel to the longitudinal axis, or alternatively, it may be inclined to a gentle helix with a full rotation of 10 turns or less, or 7 turns or less, or 3 turns or less, or 1 turn or less, around the catheter along the length of the helix. The fiber may include high-tensile materials such as multifilament yarns spun from liquid crystal polymers, such as Vectran multifilament LCP fibers.

[0066] In the implementation shown in Figure 3E, the tension member 3142 extends distally and axially along the outside (or inside) of the coil and axially toward an anchor, which may be in the form of a continuous or slitted annular ring, such as a marker band 3116 that may have the inclined distal surface described above. The tension member 3142 is preferably fixed to the anchor, thereby increasing the tensile force threshold before breakage due to tip detachment. This allows the catheter to be pulled proximal through constraints, such as intravascular constraints or kinks in the guide catheter, which may crush the marker band but not detach it. Increasing the tensile strength also provides tactile feedback to the physician when encountering constraints that may shear the marker band. In implementations with a slit 3117, the axis of the tension member 3142 may be offset circumferentially from the slit 3117, thereby avoiding the fiber being pulled through the slit.

[0067] The tension member 3142 may be fixed to the anchor in any variety of ways, including adhesive, welding, or mechanical interlocking, depending on the structure and materials involved. In the illustrated implementation, the tension member 3142 is wound around at least the distal edge of the marker band 3116, such as the distal edge of the marker band 3116, or the proximal edge of an opening that penetrates the marker band 3116. In one implementation, the tension member 3142 extends axially along the first side of the marker band beyond the marker band and is folded back towards the second side of the marker band around the distal edge of the marker band, and is fixed to the tubular body (for example, to the marker band or to itself).

[0068] In the illustrated example, the first segment 3150 of the tension member 3142 extends axially along the catheter body above or preferably below the coil, distally along the inner surface of the marker band 3116, to the distal edge 3156 of the marker band. The tension member folds back over the distal edge 3156 and extends proximal along the outer surface of the marker band along the inclined segment 3152, and is further wound circumferentially around the tubular body, such as on the marker band 3116 and / or on adjacent catheter sidewalls, to the end 3154. The tension member may be wound circumferentially by an angle of at least about 180 degrees, preferably at least about 270 degrees, or at least about 360 degrees, or at least about 450 degrees, or more. The tensioning member may be attached to the marker band or to the adjacent catheter shaft using an adhesive such as Loctite before the outer polymer jacket is applied.

[0069] Alternatively, the tension member may be folded back around the marker band and proximal to itself, and may extend proximal to a binding zone of at least about 1 cm, about 2 cm, or about 5 cm or more that can be bound to itself before being enclosed within the outer jacket.

[0070] In the illustrated implementation, the tension member intersects the marker band at a point within a range of approximately 20 to 40 degrees circumferentially offset from the center of the slit 3117. Alternatively, the tension member may intersect the marker band within a range of approximately 80 to 100 degrees offset from the slit, or within a range of approximately 170 to 190 degrees offset from the slit. In implementations where the slit is not located at the shortest axial dimension of the marker band, the above offset may be measured from the shortest axial dimension.

[0071] The radial compressibility of the marker band may preferably increase proximal to the proximal end of the marker band, thereby forming continuous or stepped compressibility. This facilitates radial compressibility at the proximal end of the marker band when the marker band encounters an obstacle (e.g., a vascular obstruction or a kink in the guide catheter) when the catheter is retracted proximal. Further proximal retraction allows the sidewall of the marker band to incline to the diameter of the distal end of the marker band, allowing the marker band to pass through the obstacle by displacing it laterally and / or gradually compressing the marker band. This, in combination with an attached tensioning member, optimizes the possibility of avoiding detachment of the marker band.

[0072] The basic geometry of the marker band 3116 described above is shown in Figure 4A. The marker band 3116 extends between the proximal cross section 3150 and the distal inclined surface 3136. The long side wall 3140 terminates distally at the distal tip 3130. The shorter side wall 3138 located on the opposite side may include an axial slit as described above.

[0073] Referring to Figure 4B, the marker band 3116 is provided with a compression mechanism that increases the radial compressibility of the proximal end of the marker band. In the illustrated implementation, the compression mechanism includes at least a first compression gap 3152 and may also include at least a second compression gap in the form of a proximal recess 3154. The first compression gap 3152 extends distally from the proximal surface 3150 for at least about 25% of the length of the long side wall 3140, and in some implementations for at least about 50%, or at least about 70%, or more.

[0074] The second compression gap may extend distally from the proximal surface 3150, rotating approximately 90 degrees in the first circumferential direction from the first compression gap 3152. At least a third compression gap may be provided, rotating approximately 90 degrees in the second circumferential direction from the first compression gap 3152.

[0075] The above structure provides an arc-shaped base 3156 in the form of the proximal edge of the marker band 3116, which is located on the plane formed by the proximal surface 3150, and this arc-shaped base 3156 will be in contact with the distal end of the coil or the distal end of other side wall reinforcing members within the catheter body. A first foot 3158 and a second foot 3160 are also formed, which are also located substantially on the plane corresponding to the proximal surface 3150, and support the marker band 3116 with respect to the distal end of the spring coil or the distal end of other catheter body reinforcing members. This allows for radial compression of the proximal end of the marker band 3116, and further supports the marker band 3116 with respect to its inclination with respect to the distal surface of the coil.

[0076] In the implementation shown in Figure 4D, the marker band 3116 having the characteristic points of the marker band in Figure 4A is modified by providing at least a first compression gap 3152 to facilitate radial compression. Depending on the desired performance, a second compression gap 3162 may be provided, and optionally, a third compression gap 3164 or further gaps may be provided. The proximal opening of the compression gap may be located on a cross-section such as the proximal face 3150 of the marker band 3116. Each compression gap preferably has a larger width as measured circumferentially at its proximal end compared to its width near its distal end. The axial depths of the compression gaps may be approximately equal to each other, so that all distal ends of the compression gaps are aligned in a cross-section substantially parallel to the proximal face 3150. Alternatively, as shown in Figure 4D, the distal ends of the compression gaps may be gradually aligned so that they are located on an inclined surface which may be substantially parallel to the inclined distal face 3136.

[0077] Alternatively, as shown in the marker bands of Figures 4F to 4I, one or more compression gaps may extend between the proximal cross section 3150 and the distal inclined surface 3136, but do not have to intersect the proximal cross section 3150 (for example, in contrast to the marker band in Figure 4E). As described above, each compression gap 3176, 3178, 3180 may have a larger width as measured circumferentially at its proximal end compared to its width near the distal end, as shown in Figures 4H to 4I. Alternatively, each compression gap 3170, 3172, 3174 may have substantially equal or substantially similar widths as measured circumferentially at its proximal end compared to its width near the distal end, as shown in Figures 4F to 4G. The angles and / or shapes of the corresponding distal ends 3170a, 3174a, 3176a, and 3180a of the compression gaps 3170, 3174, 3176, and 3180a, respectively, may be substantially equal to or similar to the angles of the distal surface 3136, as described above and as shown in Figures 4F to 4I. In each embodiment of Figures 4F to 4I, the circumferentially continuous proximal cross section 3150 is configured to allow fixation to the coil, as described elsewhere in this specification and later.

[0078] In addition to, or in place of, the tension members, any of the marker bands disclosed herein may be fixed to the coil by adhesive, welding, or mechanical interference fit. In one implementation relating to mechanical interference fit, a helical slot may be formed in the proximal sidewall of the marker band in a manner that extends circumferentially for at least about 45 degrees, and in some implementations in a manner that extends circumferentially for at least about 180 degrees, or about 360 degrees, or beyond. This allows the distal end of the helical coil to be screwed into the helical slot in the sidewall of the marker band while maintaining the ID of the lumen and the OD of the catheter across the joint.

[0079] As a further alternative, one or more tension members may be integrally formed with the marker band by laser cutting the marker band and the elongated, proximal-extending axial or helical strut tension members from a single tube stock.

[0080] The tension members may take the form of at least one, and optionally at least two, four, ten, or more struts, which may extend proximal in a linear, helical, or intersecting pattern, such as a diamond shape.

[0081] For example, the marker band in Figure 4E (optional compression gaps are omitted for clarity) includes tension members in the form of multiple intersecting struts 3166 defining a tubular body having multiple sidewall openings 3168, which may have progressively increasing or decreasing proximal compressibility. The marker band and associated tension member struts 3166 may slip-fit ​​onto a binding layer with the coil wound around the outside of at least a portion of the length of the tension members, regardless of whether adhesive is applied before the coil is wound. Alternatively, multiple proximal vertices may be formed in such a way that they are aligned to cross-sections or other geometric shapes complementary to the geometry with respect to the distal end of a support structure (e.g., a coil) within the catheter shaft, and the ends may be welded together to provide a secure joint. Furthermore, any of the embodiments in Figures 4A to 4I may include or not include axially extended slits, as described elsewhere in this specification.

[0082] Referring to Figures 5A and 5B, an example of a layering pattern of outer jacket segments for a gradually flexible catheter of the type described in relation to Figure 2 is illustrated. The distal segment 3038 may have a length in the range of approximately 1 cm to 3 cm and a durometer of approximately less than 35 D or less than 30 D. The adjacent proximal segment 3036 may have a length in the range of approximately 4 cm to 6 cm and a durometer of approximately less than 35 D or less than 30 D. The adjacent proximal segment 3034 may have a length in the range of approximately 4 cm to 6 cm and a durometer of approximately 35 D or less. The adjacent proximal segment 3032 may have a length in the range of approximately 1 cm to 3 cm and a durometer in the range of approximately 35 D to approximately 45 D (e.g., 40 D). The adjacent proximal segment 3030 may have a length in the range of approximately 1 cm to 3 cm and a durometer in the range of approximately 50 D to approximately 60 D (e.g., approximately 55 D). The adjacent proximal segment 3028 may have a length in the range of approximately 1 cm to 3 cm and a durometer in the range of approximately 35 D to approximately 50 D, and even further in the range of approximately 35 D to approximately 60 D (e.g., approximately 55 D). The adjacent proximal segment 3026 may have a length in the range of approximately 1 cm to 3 cm and a durometer of at least approximately 60 D, typically less than approximately 75 D. The more proximal segments may have a durometer of at least approximately 65 D or approximately 70 D. The two or three most distal segments may contain a material such as Tecotan, and the more proximal segments may contain PEBAX® or other catheter jacket materials known in the art. At least three, five, seven, nine, or more individual segments may be used, such that the change in durometer between the highest and lowest values ​​along the length of the catheter shaft is at least about 10D, preferably at least about 20D, and in some implementations at least about 30D, or 40D, or more.

[0083] Exemplary Embodiments

[0084] A neurovascular catheter with enhanced tensile strength,

[0085] A long, flexible tube having a proximal end, a distal end, and a side wall defining the central lumen,

[0086] A radiopaque marker is adjacent to the distal end and extends over at least a portion of the outer circumference of the tube,

[0087] A tension support extending axially within the side wall, Includes one or more of the following:

[0088] A neurovascular catheter in which a tension support extends distally along the first side of a radiopaque marker, is folded back around the distal edge of the radiopaque marker, and further extends along the second side of the radiopaque marker.

[0089] The tension support is a neurovascular catheter in any example described herein, which includes multiple fibers.

[0090] The tension support comprises a neurovascular catheter in any example described herein, comprising a Vectran multifilament liquid crystal polymer fiber.

[0091] A neurovascular catheter in any example described herein, wherein the tension support extends distally along the radially inward surface of the marker, extends around the distal end of the marker, and further extends circumferentially around the radially outward surface of the marker.

[0092] The tension support extends circumferentially around the marker for at least about 180 degrees in any example of a neurovascular catheter described herein.

[0093] A radiopaque marker comprises a proximal and distal surface, the distal surface being inclined at an angle between approximately 45 and 80 degrees with respect to the longitudinal axis of the central lumen, in any example described herein of a neurovascular catheter.

[0094] A neurovascular catheter in any example described herein, comprising a distal port having an elliptical opening, wherein the elliptical opening has an area that is at least about 105% compared to the transverse cross-sectional area of ​​the central lumen.

[0095] A neurovascular catheter in any example described herein, in which the area of ​​the elliptical opening is at least about 110% compared to the cross-sectional area of ​​the central lumen.

[0096] A neurovascular catheter in any example described herein, wherein the elliptical opening is inclined at an angle within the range of approximately 55 to 65 degrees with respect to the longitudinal axis of the central lumen.

[0097] The proximal surface on the radiopaque marker is substantially perpendicular to the longitudinal axis of the neurovascular catheter in any example described herein.

[0098] The distal end is spaced apart from the distal surface of the radiopaque marker, thereby forming an advancing segment of the tubular body, in any example described herein, of a neurovascular catheter.

[0099] The forward segment of the neurovascular catheter in any example described herein has an axial length in the range of approximately 0.1 mm to approximately 5 mm.

[0100] In any example described herein, the axial length of the forward segment at the anterior edge of the tubular body is greater than the axial length of the forward segment at the posterior edge of the tubular body of a neurovascular catheter.

[0101] A radiopaque marker is a neurovascular catheter in any example described herein, comprising an annular ring having at least one axial slit.

[0102] A neurovascular catheter in any example described herein, further comprising an inner liner, wherein the tension support extends axially between the helical coil and the inner liner.

[0103] A neurovascular catheter, in any example described herein, is configured to withstand a tension of at least approximately 3.5 pounds before failure.

[0104] A neurovascular catheter, in any example described herein, is configured to withstand a tension of at least about 5 pounds before failure.

[0105] A neurovascular catheter, in any example described herein, is configured to withstand a tension of at least about 7 pounds before failure.

[0106] A neurovascular catheter in any example described herein, wherein the side wall includes an outer jacket having a plurality of tubular segments, the proximal tubular segments of the plurality of tubular segments having a durometer of at least about 60 D, and the distal tubular segments of the plurality of tubular segments having a durometer of up to about 35 D.

[0107] It is a neurovascular catheter,

[0108] A long, flexible tube body having a proximal end, an inclined distal end, and a side wall defining a central lumen,

[0109] The distal tip is located on the first lateral part of the inclined distal end,

[0110] A pre-set curve located in the distal zone of the tube body, Includes one or more of the following:

[0111] A neurovascular catheter with its distal tip located on the concave side of a curve.

[0112] A neurovascular catheter in any example described herein, further comprising a tubular radiopaque marker embedded in the side wall, wherein the tubular radiopaque marker includes a proximal and a distal surface, and the distal surface of the radiopaque marker is inclined at an angle in the range of approximately 45 to approximately 80 degrees with respect to the longitudinal axis of the central lumen.

[0113] A neurovascular catheter in any example described herein, comprising a distal port having an elliptical opening, wherein the elliptical opening has an area that is at least about 105% of the cross-sectional area of ​​the central lumen.

[0114] A neurovascular catheter in any example described herein, in which the area of ​​the elliptical opening is at least about 110% compared to the cross-sectional area of ​​the central lumen.

[0115] A neurovascular catheter in any example described herein, in which the area of ​​the elliptical opening is in the range of approximately 110% to approximately 125% compared to the cross-sectional area of ​​the central lumen.

[0116] A neurovascular catheter in any example described herein, wherein the elliptical opening is inclined at an angle within the range of approximately 55 to 65 degrees with respect to the longitudinal axis of the central lumen.

[0117] A neurovascular catheter in any example described herein, wherein the distal surface of the radiopaque marker is inclined at an angle within the range of approximately 55 to 65 degrees with respect to the longitudinal axis of the central lumen.

[0118] The proximal surface on the radiopaque marker is substantially perpendicular to the longitudinal axis of the neurovascular catheter in any example described herein.

[0119] The distal end is spaced apart from the distal surface of the radiopaque marker, thereby forming an advancing segment of the tubular body, in any example described herein, of a neurovascular catheter.

[0120] The forward segment of the neurovascular catheter in any example described herein has an axial length in the range of approximately 0.1 mm to approximately 5 mm.

[0121] In any example described herein, the axial length of the forward segment at the anterior edge of the tubular body is greater than the axial length of the forward segment at the posterior edge of the tubular body of a neurovascular catheter.

[0122] In any example of a neurovascular catheter described herein, the axial length of the forward segment at the anterior edge of the tubular body is at least about 20% longer than the axial length of the forward segment at the posterior edge of the tubular body.

[0123] A radiopaque marker is a neurovascular catheter in any example described herein, comprising at least one axial slit.

[0124] A neurovascular catheter in any example described herein, further comprising a tension support for increasing tensile resistance in the distal zone.

[0125] The tension support is a neurovascular catheter in any example described herein, which includes an axially extended filament.

[0126] A neurovascular catheter in any example described herein, in which an axially extended filament is supported between an inner liner and a helical coil.

[0127] A neurovascular catheter in any example described herein, in which axially extended filaments increase the tensile strength of the tubular body to at least about 2 pounds.

[0128] It is a neurovascular catheter,

[0129] A long, flexible tube body having a proximal end, a distal zone, and side walls defining a central lumen,

[0130] A tubular radiopaque marker band embedded in the side wall in the distal zone, Includes one or more of the following:

[0131] The radiopaque marker band has a first axial length measured along the side wall at a first circumferential position, and a longer second axial length measured along the side wall at a second circumferential position offset approximately 180 degrees around the catheter's circumference from the first position.

[0132] The tubular body is a neurovascular catheter with a pre-set curve within the distal zone.

[0133] A neurovascular catheter in any example described herein, wherein the pre-set curve has a concave side and a convex side, and the longer second axial length of the marker is located on the concave side of the curve.

[0134] It is a neurovascular catheter,

[0135] A long, flexible tube body having a proximal end, an inclined distal end, and a side wall defining a central lumen,

[0136] A pre-defined curve within the distal zone of a tube body, having a convex side and a concave side,

[0137] Filaments extending axially along the side wall of the distal zone, Includes one or more of the following:

[0138] A neurovascular catheter in which the distal tip is located on the concave side of the curve, and the filament is located on the convex side of the curve.

[0139] It is a neurovascular catheter,

[0140] A long, flexible tube body having a proximal end, an inclined distal end, and a side wall defining a central lumen,

[0141] The distal tip is located on the first lateral part of the inclined distal end,

[0142] A predetermined curve within the distal zone of the tube, Includes one or more of the following:

[0143] A neurovascular catheter with its distal tip located on the concave side of a curve.

[0144] A neurovascular catheter in any example described herein, further comprising a tubular radiopaque marker embedded in the side wall, wherein the tubular radiopaque marker includes a proximal and a distal surface, and the distal surface of the radiopaque marker is inclined at an angle in the range of approximately 45 to approximately 80 degrees with respect to the longitudinal axis of the central lumen.

[0145] A neurovascular catheter in any example described herein, comprising a distal port having an elliptical opening, wherein the elliptical opening has an area that is at least about 105% of the cross-sectional area of ​​the central lumen.

[0146] A neurovascular catheter in any example described herein, in which the area of ​​the elliptical opening is at least about 110% compared to the cross-sectional area of ​​the central lumen.

[0147] A neurovascular catheter in any example described herein, in which the area of ​​the elliptical opening is in the range of approximately 110% to approximately 125% compared to the cross-sectional area of ​​the central lumen.

[0148] A neurovascular catheter in any example described herein, wherein the elliptical opening is inclined at an angle within the range of approximately 55 to 65 degrees with respect to the longitudinal axis of the central lumen.

[0149] A neurovascular catheter in any example described herein, wherein the distal surface of the radiopaque marker is inclined at an angle within the range of approximately 55 to 65 degrees with respect to the longitudinal axis of the central lumen.

[0150] The proximal surface on the radiopaque marker is substantially perpendicular to the longitudinal axis of the neurovascular catheter in any example described herein.

[0151] The distal end is spaced apart from the distal surface of the radiopaque marker, thereby forming an advancing segment of the tubular body, in any example described herein, of a neurovascular catheter.

[0152] The forward segment of the neurovascular catheter in any example described herein has an axial length in the range of approximately 0.1 mm to approximately 5 mm.

[0153] In any example described herein, the axial length of the forward segment at the anterior edge of the tubular body is greater than the axial length of the forward segment at the posterior edge of the tubular body of a neurovascular catheter.

[0154] In any example of a neurovascular catheter described herein, the axial length of the forward segment at the anterior edge of the tubular body is at least about 20% longer than the axial length of the forward segment at the posterior edge of the tubular body.

[0155] A radiopaque marker is a neurovascular catheter in any example described herein, comprising at least one axial slit.

[0156] A neurovascular catheter in any example described herein, further comprising a tension support for increasing tensile resistance in the distal zone.

[0157] The tension support is an enhanced flexibility neurovascular catheter, as described herein, comprising an axially extended filament.

[0158] A neurovascular catheter in any example described herein, in which an axially extended filament is supported between an inner liner and a helical coil.

[0159] A neurovascular catheter in any example described herein, in which axially extended filaments increase the tensile strength of the tubular body to at least about 2 pounds.

[0160] It is a neurovascular catheter,

[0161] A long, flexible tube body having a proximal end, a distal zone, and side walls defining a central lumen,

[0162] A tubular radiopaque marker band embedded in the side wall in the distal zone, Includes one or more of the following:

[0163] The radiopaque marker band has a first axial length measured along the side wall at a first circumferential position, and a longer second axial length measured along the side wall at a second circumferential position offset approximately 180 degrees around the catheter's circumference from the first position.

[0164] The tubular body is a neurovascular catheter with a pre-set curve within the distal zone.

[0165] A neurovascular catheter in any example described herein, wherein the pre-set curve has a concave side and a convex side, and the longer second axial length of the marker is located on the concave side of the curve.

[0166] It is a neurovascular catheter,

[0167] A long, flexible tube body having a proximal end, an inclined distal end, and a side wall defining a central lumen,

[0168] A pre-defined curve within the distal zone of a tube body, having a convex side and a concave side,

[0169] Filaments extending axially along the side wall of the distal zone, Includes one or more of the following:

[0170] A neurovascular catheter in which the distal tip is located on the concave side of the curve, and the filament is located on the convex side of the curve.

Claims

1. A neurovascular catheter with enhanced tensile strength, A long, flexible tube having a proximal end, a distal end, and side walls defining a central lumen, A radiopaque marker adjacent to the distal end and extending to at least a portion of the outer circumference of the long, flexible tube body, The system comprises a tension support extending axially within the side wall, A neurovascular catheter in which the tension support extends distally along the first side of the radiopaque marker, is folded back around the distal edge of the radiopaque marker, and extends along the second side of the radiopaque marker.

2. The neurovascular catheter according to claim 1, wherein the tension support comprises a plurality of fibers.

3. The neurovascular catheter according to claim 2, wherein the tension support comprises a Vectran multifilament liquid crystal polymer fiber.

4. The neurovascular catheter according to claim 1, wherein the tension support extends distally along the radially inward surface of the radiopaque marker, extends around the distal end of the radiopaque marker, and extends circumferentially around the radially outward surface of the radiopaque marker.

5. The neurovascular catheter according to claim 4, wherein the tension support extends circumferentially for at least 180 degrees around the radiopaque marker.

6. The neurovascular catheter according to claim 1, wherein the radiopaque marker comprises a proximal surface and a distal surface, and the distal surface is inclined at an angle within the range of 45 to 80 degrees with respect to the longitudinal axis of the central lumen.

7. The neurovascular catheter according to claim 1, comprising a distal port having an elliptical opening, wherein the elliptical opening includes an area that is at least 105% of the transverse cross-sectional area of ​​the central lumen.

8. The neurovascular catheter according to claim 7, wherein the area of ​​the elliptical opening is at least 110% compared to the cross-sectional area of ​​the central lumen.

9. The neurovascular catheter according to claim 7, wherein the elliptical opening is inclined at an angle within the range of 55 to 65 degrees with respect to the longitudinal axis of the central lumen.

10. The neurovascular catheter according to claim 1, wherein the proximal surface on the radiopaque marker is perpendicular to the longitudinal axis of the central lumen.

11. The neurovascular catheter according to claim 1, wherein the distal end of the long flexible tube is spaced apart from the distal surface of the radiopaque marker to form an advancing segment having a leading sidewall portion and a trailing sidewall portion of the long flexible tube, the leading sidewall portion having an axial length measured between the distal end of the radiopaque marker and the distal tip of the long flexible tube, and the trailing sidewall portion is located at a position 180° from the leading sidewall portion around the neurovascular catheter.

12. The neurovascular catheter according to claim 11, wherein the forward segment has an axial length in the range of 0.1 mm to 5 mm.

13. The neurovascular catheter according to claim 11, wherein the axial length of the subsequent sidewall portion is the length from the distal surface of the radiopaque marker to the distal end of the long flexible tube body, and the axial length of the leading sidewall portion of the forward segment is greater than the axial length of the subsequent sidewall portion of the forward segment.

14. The neurovascular catheter according to claim 1, wherein the radiopaque marker comprises an annular ring having at least one axial slit.

15. The neurovascular catheter according to claim 1, further comprising an inner liner, wherein the tension support extends axially between the helical coil and the inner liner.

16. The neurovascular catheter according to claim 1, configured to withstand a tension of at least 1.58757 kg before the radiopaque marker detaches from the long, flexible tube.

17. The neurovascular catheter according to claim 16, configured to withstand a tension of at least 2.26796 kg before the radiopaque marker detaches from the long, flexible tube.

18. The neurovascular catheter according to claim 17, configured to withstand a tension of at least 3.17515 kg before the radiopaque marker detaches from the long, flexible tube.

19. The neurovascular catheter according to claim 1, wherein the side wall comprises an outer jacket having a plurality of tubular segments, the proximal tubular segments of the plurality of tubular segments having a durometer of at least 60 D, and the distal tubular segments of the plurality of tubular segments having a durometer of up to 35 D.

20. The neurovascular catheter according to claim 1, wherein the radiopaque marker comprises a tubular sidewall having a proximal end and a distal end, and at least one compression mechanism for increasing the compressibility of the proximal end.

21. The neurovascular catheter according to claim 20, wherein at least one of the compression mechanisms includes at least one compression gap in the tubular sidewall, the at least one compression gap opening at the proximal end of the tubular sidewall and extending distally.

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