Micromachined catheter device with high axial strength

Abstract

The present disclosure describes a microfabricated intravascular device configured for high axial strength while also maintaining effective bending flexibility. The tubular member includes a series of circumferentially extending rings connected to one another by a series of axially extending beams. Transverse cuts separate and define the rings. A series of axial cuts are aligned with the beams and extend partially from the beams into adjacent rings, thereby causing the beam lengths to partially overlap within the axial lengths of the adjacent rings. This increases the functional length of the beams to provide bending flexibility while still providing sufficient ring structure to provide effective axial stiffness.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Patent Application No. 17 / 493,265, entitled "Microfabricated Catheter Devices with High Axial Strength," filed October 4, 2021, which claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 087,410, entitled "Microfabricated Catheter Devices with High Axial Strength," filed October 5, 2020. Each of the foregoing applications is incorporated by reference in its entirety. [Background technology]

[0002]

[0002] Guidewires and catheters are often utilized in the medical field to perform delicate procedures deep within the body's vascular system. Typically, a catheter is inserted into a patient's femoral, radial, carotid, or jugular vessels and navigated through the patient's vascular system to the heart, brain, or other target anatomical location. Often, a guidewire is first advanced to the target anatomical location, and one or more catheters are subsequently passed over the guidewire and advanced to the desired location. Once in position, the catheter can be used to aspirate a blood clot or other obstruction, or to deliver a drug, stent, embolization device, radiopaque dye, or other device or substance to treat the patient.

[0003] In many applications, such catheters must be routed through the tortuous bends and curves of vascular passageways to reach target anatomical sites. Ideally, these catheters include design features that allow for effective navigation of such tortuous passageways. For example, the catheter should be sufficiently flexible to navigate the bends of the vasculature, yet also be able to provide sufficient pushability (i.e., the ability to transmit axial force from the proximal to the distal portion) and torqueability (the ability to transmit torque from the proximal to the distal portion).

[0004] For example, if a catheter lacks sufficient axial stiffness, it may be difficult for the operator to push the catheter forward through the vasculature. That is, axial forces applied by the operator at the proximal end may cause the catheter to compress and "accordion" axially rather than being effectively transmitted to the distal end of the catheter. Designing the catheter to have a higher axial stiffness can alleviate this problem. However, increasing the axial stiffness of a catheter can create other problems that hinder the catheter's effectiveness. For example, increasing the axial stiffness of a catheter typically also increases the bending stiffness of the catheter, which can be detrimental if the device remains with insufficient bending flexibility.

[0005]

[0005] Therefore, there is currently a need for a catheter device with features designed to provide effective axial stiffness without unduly interfering with desired properties such as flexibility and torqueability of the device. Summary of the Invention [Means for solving the problem]

[0006]

[0006] The present disclosure describes microfabricated intravascular devices configured for high axial strength while also maintaining effective bending flexibility.

[0007] In one embodiment, the tubular member includes a series of circumferentially extending rings connected to one another by a series of axially extending beams. A plurality of transverse cuts separate and define the rings. The transverse cuts are located between adjacent rings and extend transversely to the longitudinal axis of the tubular member, but do not extend sufficiently to completely cut through the tubular member, thereby leaving the beams positioned between the rings.

[0008] In some embodiments, at least some of the transverse cuts are wedge-shaped. For example, one or more of the transverse cuts may be narrower near the corresponding beam and then widen as they extend circumferentially away from the corresponding beam.

[0009] In some embodiments, a series of axial cuts are aligned with the beam and extend partially from the beam into an adjacent ring, such that the beam length overlaps partially within the axial length of the adjacent ring. This increases the functional length of the beam to provide bending flexibility while still providing sufficient ring structure to provide effective axial stiffness.

[0010] In some embodiments, at least some of the axial cuts are wedge-shaped. For example, one or more axial cuts may be wider at the edge of an adjacent ring and then taper as they extend axially into the adjacent ring.

[0011] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor may it be used as an indicator of the scope of the claimed subject matter.

[0012]

[0012] Various objects, features, characteristics and advantages of the invention will become apparent and be more readily appreciated from the following description of the embodiments, read in conjunction with the accompanying drawings and appended claims, all of which form a part of this specification. [Brief explanation of the drawings]

[0013] [Figure 1]

[0013] An exemplary catheter device is shown that may be modified with the cutting patterns described herein to provide a catheter with high axial strength. [Figure 2A]

[0014] FIG. 1 is a detailed view of a micromachined distal section of a catheter with a conventional two-beam cutting pattern. [Figure 2B]

[0015] FIG. 11 is a detailed view of the micromachined distal section of the catheter with a three-beam cutting pattern. [Figure 2C]

[0015] FIG. 1 is a detailed view of a micromachined distal section of a catheter having a one-beam cutting pattern. [Figure 3]

[0016] Figure 3A is a schematic diagram illustrating how a micromachined catheter section can compress and "accordion" under an axial load. Figure 3B is a schematic diagram illustrating how a micromachined catheter section can compress and "accordion" under an axial load. [Figure 4]

[0017] FIG. 10 shows a micromachined catheter section having relatively thick ring elements for increased axial stiffness, but concentrating bending forces on the axial beam elements. [Figure 5]

[0018] Figure 5A shows an exemplary micromachined catheter section with a cut pattern that provides effective axial stiffness without excessively increasing bending stiffness, thereby providing a high bending stiffness to axial stiffness ratio. Figure 5B shows an exemplary micromachined catheter section with a cut pattern that provides effective axial stiffness without excessively increasing bending stiffness, thereby providing a high bending stiffness to axial stiffness ratio. DETAILED DESCRIPTION OF THE INVENTION

[0014] Overview

[0019] FIG. 1 shows an example of a conventional catheter device 10 that can be improved by incorporating the unique high-pressure strength pattern described below. The catheter device 10 includes a proximal section 40 and a distal section 50. A radiopaque marker 16 may be located near the distal end. A hub and / or port 42 may be located at the proximal end. Due to the particular advantages of high-pressure strength designs in catheter applications, most of the examples described herein refer to catheter devices. However, it will be understood that in some embodiments, the same features may be applied to other microfabricated components of other intravascular devices, such as guidewires.

[0015]

[0020] At least a portion of the distal section 50 is micromachined with one or more cut patterns intended to enhance the effectiveness of the device. Previously, such cut patterns focused on increasing the bending flexibility of the device while maintaining good torqueability. However, as described below, improved cut patterns are now designed to increase the bending flexibility of the device while optimizing pushability (i.e., optimizing axial stiffness).

[0016]

[0021] Although the improved cutting pattern sacrifices some of the torqueability of conventional cutting patterns, the device's increased pushability and improved ratio of axial stiffness to bending stiffness provide better overall functionality, particularly in applications where axial stiffness is likely to be more important than torqueability, such as many catheter applications. For example, unlike guidewires, catheters lack a solid core and therefore inherently lack good axial stiffness. Because catheters are often routed over guidewires, the guidewire may be utilized to segment blood vessels and reach anatomical targets. Therefore, pushability is often more important than torqueability in catheters.

[0017]

[0022] The length of the catheter 10 may vary according to the needs of a particular application, but is typically in the range of approximately 125 cm to 175 cm. The microfabricated portion may vary according to the needs of a particular application, but typically has a length of approximately 50 to 90 cm. The most distal section (e.g., the most distal section is approximately 10 to 30 cm) typically has a higher degree of microfabrication because it is more flexible. Like the catheter length, the catheter diameter may vary according to the needs of the application. An example may be in the range of approximately 2F to 10F, although sizes outside this range may also be utilized where appropriate (outside of typical neurological and coronary applications). Aspiration catheters for use in neurovascular procedures are one exemplary application of the high compressive strength devices described herein.

[0018]

[0023] The micromachined sections of catheter 10 include a plurality of cuts extending transversely to the longitudinal axis of the catheter to form "rings" and "beams." Rings are circumferentially extending ring-like structures, and beams are uncut, axially extending sections of tubing that connect adjacent rings. Sections of catheter 10 may be defined herein according to the number of beams located between each consecutive pair of rings.

[0019]

[0024] 2A-2C show conventional microfabricated configurations to illustrate general features and define general terms. The improved features described further below may be applied to any of the conventional configurations shown in FIGS. 2A-2C.

[0020]

[0025] FIG. 2A, for example, depicts a “two-beam section” 15 of a micromachined tubular member. The two-beam section includes a series of consecutive rings 14 and a series of beams 12 extending between and connecting the rings. As shown, each pair of adjacent rings 14 is connected by two beams 12. FIG. 2B illustrates a “three-beam section” 20 in which three beams 22 are disposed between each set of adjacent rings 24. FIG. 2C illustrates a “one-beam section” 30 in which one beam 32 extends between and connects each pair of adjacent rings 34. While most of the examples described herein refer to two-beam configurations, it will be understood that the same features may apply to other embodiments having one-beam or three-beam configurations, or even configurations having other numbers of beams between each set of adjacent rings.

[0021]

[0026] 3A and 3B show schematically how microfabricated catheter sections can compress and "accordion" under axial load. FIG. 3A shows a side view of a conventional two-beam section (shown in FIG. 2A) comprising beam 12 and ring 14. FIG. 3B shows that when an axial load (i.e., a pushing force) is applied, ring 14 may flex slightly and absorb some of the axial load rather than completely transferring it to the more distal section of the device. This reduces the pushability of the device and makes it more difficult for the operator to track the catheter over the guidewire and / or reach the desired anatomical target.

[0022]

[0027] One way to increase the axial stiffness of the device is to simply increase the length of the ring along the axial direction (sometimes this dimension is also referred to as the "thickness," "axial length," or "width" of the ring). FIG. 4 shows an embodiment with an increased axial length of the ring 64. While increasing the axial length of the ring 64 can indeed increase the axial stiffness of the device, there are practical limits on how much the axial length of the ring can be increased. For example, if the axial length of the ring 64 is increased too much relative to the size of the beam 62, excessive bending stresses will be concentrated in the beam 62. At some point, the device will no longer be able to bend sufficiently without plastic deformation in the beam 62. Therefore, simply increasing the ring size until the desired axial stiffness is reached is not a practical option.

[0023] High pressing strength micromachined sections

[0028] 5A and 5B illustrate embodiments of high-pressure strength cut patterns that may be provided on tubular members and utilized in catheter devices such as the device shown in FIG. 1. The cut patterns advantageously provide effective axial stiffness while still maintaining good bending flexibility. Furthermore, unlike simply expanding the thickness of the rings, the illustrated configuration allows for high relative axial stiffness without excessively concentrating stress on the beam. FIG. 5A illustrates an exemplary tubular member 100 (e.g., the distal section of a catheter), and FIG. 5B illustrates the same cut pattern when the tubular member 100 is cut in half along its longitudinal axis and unfolded to lie flat.

[0024]

[0029] As shown, the elongate tubular member 100 includes a series of circumferentially extending rings 114 connected by a series of axially extending beams 112. The rings 114 have a length "L" in the axial direction. This dimension may sometimes be referred to as the ring "width," "axial length," or ring "thickness," but will typically be referred to herein as the length (or more specifically, the axial length) for consistency, as this is the dimension parallel to the longitudinal axis of the tubular member 100. With respect to the beams 112, the "length" of the beam 112 is used herein to refer to the dimension along the axial direction, whereas the "width" or "thickness" of the beam is used herein to refer to the dimension along the circumference of the tubular member 100.

[0025]

[0030] The rings 114 are spaced apart by transverse cuts 118. Each transverse cut 118 extends transversely relative to the longitudinal axis of the tubular member 100, but does not extend completely through the tubular member 100. Thus, the tubular member 100 somewhat resembles the conventional configuration shown in FIGS. 2A-2C. The illustrated tubular member 100 includes two beams 112 between each pair of adjacent rings 114, and thus represents a two-beam section. However, as discussed above, other embodiments may include configurations with a different number of beams between each pair of adjacent rings (e.g., a one-beam or three-beam configuration).

[0026]

[0031] 2A-2C, however, the illustrated embodiment also includes a series of axial cuts 116 aligned with the beams 112. Each axial cut 116 begins along the edge of the corresponding beam 112 and extends partially axially into the adjacent ring, such that the corresponding beam 112 partially "overlaps" within the axial length of the adjacent beam 112.

[0027]

[0032] 5A and 5B each have an associated axial cut 116 extending to each of the adjacent rings 114, representing a preferred embodiment. However, other embodiments may include fewer axial cuts 116. For example, some embodiments may have beams associated with only axial cuts extending to one of two adjacent rings (e.g., only the proximal adjacent ring or only the distal adjacent ring, but not both). In another embodiment, the tubular member 100 may have some beams 112 associated with axial cuts 116 and other beams 112 not associated with axial cuts 116.

[0028]

[0033] Because portions of beams 112 are overlapped within the axial length of rings 114, the result is a more flexible beam structure per unit length of tubing member 100 compared to the same structure without axial cuts 116. In other words, the illustrated cut pattern allows rings 114 to be relatively thick (i.e., have a relatively long axial length) along most of the circumference of the device, while providing additional functional length for beams 112 and thus greater bending flexibility for the device. Thus, the overall structure can provide good axial stiffness without excessively increasing bending stiffness, resulting in a device with a favorable ratio of axial stiffness to bending stiffness.

[0029]

[0034] 5A and 5B, the transverse cuts 118 may have a wedge shape. The wedge-shaped cuts 118 advantageously provide additional void space, allowing the device to bend along the inside of a curve. Similarly, in embodiments where the gaps in the device are filled with a polymer material, as described further below, the wedge-shaped cuts 118 provide additional space for the polymer to compress toward the inside of the curve.

[0030]

[0035] For example, at a given axial location on the tubular member 110, the transverse cuts 118 may be narrower near the beams 112 and then wider away from the beams 112. Starting at one of the beams 112 and extending circumferentially, the cuts 118 may widen until they reach an apex 119 and then begin to narrow again as they continue to extend toward the opposite beam 112. As shown, the apex 119 may be located equidistant from the two beams 112, although in other embodiments, one or more of the transverse cuts 118 may be asymmetric, and the apex 119 need not be equidistant from each beam 112.

[0031]

[0036] The size and shape of the wedge-shaped transverse cut 118 may be varied. Generally, a wider gap provides more room for tighter bends, but at the cost of reduced axial stiffness. Thus, the wedge angle and / or gap size may be increased for applications requiring greater bending flexibility, or the wedge angle and / or gap size may be decreased for applications requiring greater axial stiffness. Alternatively, the wedge angle and / or gap may be increased for regions of the device requiring greater flexibility and decreased for regions of the device requiring greater axial strength. In one non-limiting example, the wedge angle and / or gap size may be increased in more distal sections of the device relative to more proximal sections of the device. In some embodiments, at least in the distal section of tubular member 100, the gap size at apex 119 (i.e., the widest portion of transverse cut 118) may be between about 25% and about 100% of the length of ring 114, or between about 35% and about 75% of the length of ring 114. Additionally or alternatively, the wedge angle may gradually increase or decrease from one section to another, such that there is a gradual change in wedge angle from the first section to the second section.

[0032]

[0037] The angle "A" at which the wedge of the transverse cut 118 extends from the beam 112 may range from about 2 degrees to about 35 degrees, from about 5 degrees to about 25 degrees, or from about 10 degrees to about 20 degrees. In other words, if an angle of 0 degrees represents a straight vertical cut, the wedge-shaped cut 118 preferably has an angle greater than 0 degrees but less than 35 degrees, more typically less than about 25 degrees or less than about 20 degrees.

[0033]

[0038] In the illustrated embodiment, the transverse cuts 118 are angled in both axial directions (proximally and distally). That is, starting at a given beam 112 and moving circumferentially vertically around the tubular member 100 toward another beam 112, the corresponding transverse cuts 118 are angled away from vertical along both the proximally adjacent ring 114 and the distally adjacent ring 114. Other embodiments may include transverse cuts 118 that are angled away from vertical in only one direction (i.e., only along the proximally adjacent ring or only along the distally adjacent ring).

[0034]

[0039] One or more of the axial cuts 116 may be wedge-shaped. As shown in FIGS. 5A and 5B , the axial cuts 116 may be somewhat wider where the cut “begins” along the edge of a ring and narrow as it extends axially further into an adjacent ring. Like the wedge shape of the transverse cuts 118, the wedge shape of the axial cuts 116 may provide additional clearance, allowing for greater movement of the rings 114 relative to the beam 112 and allowing the rings 114 to better bend toward each other along the inside of a curve when the tubular member 100 is bent. If a straight axial cut (parallel to the longitudinal axis) has a cut angle of 0 degrees, the angle of the axial cuts 116 may be greater than 0 degrees but less than about 35 degrees, more typically less than about 25 degrees or less than about 20 degrees.

[0035]

[0040] At least in the distal section of the tubular member 100, the axial cut 116 may extend into an adjacent ring 114 a distance equal to about 25% to about 75%, or about 35% to about 65%, or about 45% to about 55% of the axial length of the ring 114. The further the axial cut 116 extends into the ring 114, the greater the added functional length of the associated beam 112. However, this comes at the expense of some of the ring's structure; thus, a deeper axial cut 116 reduces some of the ring's structure that would otherwise contribute to axial stiffness, at least in the particular portion of the ring 114 coincident with the axial cut 116 and beam 112. In some applications, the axial cut 116 may extend further into the ring 114 to increase the length of the associated beam 112 and, therefore, the flexibility of the tubular member 100. In other applications, the axial cut 116 may extend further into the ring 114 in one section of the device than in another section of the device. For example, the axial cut 116 may be increased or decreased near the distal or proximal ends of the device.

[0036]

[0041] Accordingly, the size of the beam length may also increase or decrease. This may be a result of the length of the axial cut 116, as described above. Alternatively, or additionally, the size of the beam length may be varied independently of the axial cut 116 by increasing or decreasing the length of the portion of the beam 112 between corresponding pairs of rings 114. In some applications, one section of the tubular member 100 may have a relatively longer beam length than the beam length of another section to provide different flexibility to the device in different portions of the device. Finally, the beam length may vary gradually from the first section to the second section, such that the beam length gradually increases or decreases between the two sections.

[0037]

[0042] The size of the beam width, or beam thickness, may vary depending on the application of the device, the overall size of the device, and / or the section of the device. In some applications, one section of the device may have a relatively larger beam width than a second section of the device. Additionally, the beam width may vary gradually such that the beam width of each beam 112 gradually increases between the first and second sections.

[0038]

[0043] Ring size may vary depending on the overall size of the device and / or the section of the device. For example, in the distal section of the tubular member 100, the rings 114 may have a ring length to ring diameter ratio of about 0.25 to 0.8, or about 0.35 to 0.65, or about 0.4 to 0.6. In some applications, the entire device utilizes similar ring sizes, with each ring 114 having a similar axial length. Alternatively, in some applications, the ring size of one or more sections of the device differs from one or more other sections of the device, such that one or more sections of the device have greater axial strength relative to one or more other sections. In some embodiments, the ring axial length may vary gradually along the device, such that the ring size gradually increases or decreases from one section to another.

[0039]

[0044] As shown, the beams 112 between each pair of adjacent rings 114 may be equally circumferentially spaced (e.g., spaced 180 degrees apart in a two-beam configuration), although other embodiments may arrange the beams so that they are not equally circumferentially spaced. A set of beams 112 may be rotationally offset from adjacent sets of beams 112. For example, the set of beams 112 between a given pair of adjacent rings may be rotationally offset from the set of beams in the preceding and / or succeeding pair of adjacent rings. In the illustrated embodiment, the rotational offset is 90 degrees. That is, a first pair of beams is provided at a first rotational position, and then, moving along the length of the tubular member 100, the next pair of beams is offset 90 degrees from the first pair.

[0040]

[0045] Other rotational offsets may be utilized. The rotational offset may be, for example, from about 5 degrees to about 90 degrees. A rotational offset of less than 90 degrees provides a helical pattern that minimizes the preferred bend axis in the tubular member 100. Other advantageous "distributed" beam arrangements may alternatively be utilized to avoid the preferred bend axis. These are described in more detail in U.S. Patent Application No. 16 / 616,139, entitled "Micro-Fabricated Medical Device Having a Non-Helical Cut Arrangement," which is incorporated herein by reference in its entirety.

[0041]

[0046] The tubular member 100 may be formed from any material or combination of materials suitable for intravascular applications. Examples include polymeric materials such as polyetheretherketone (PEEK), other polymers that can be formulated with similar ranges for elastic modulus, stainless steel, and superelastic materials such as nitinol. A preferred embodiment is formed from nitinol.

[0042]

[0047] As briefly mentioned above, a polymeric material may be added to the tubing member 100 to fill the gaps created by the transverse cuts 118 and the axial cuts 116 and enable the tubing member 100 to transport fluid. The polymeric material may include an elastomer such as a polyether block amide and / or another similar polymer.

[0043]

[0048] Another advantage of the described embodiments compared to conventional configurations relates to the relatively smaller open gap space along the exterior surface of the tubular member 100. Because the improved cutting pattern allows for an increased axial length of the rings, a smaller portion of the total exterior surface area is taken up by gaps. This means that proportionally less of the device relies on the polymer material to maintain its fluid-tight integrity under pressure, and therefore the device is less likely to fail when delivering fluid under pressure.

[0044]

[0049] Other embodiments may omit the polymer material. For example, certain applications may not require fluid delivery or aspiration, and may appropriately utilize a device with unfilled gaps. Leaving the gaps open may be advantageous in some applications because adding polymer to the transverse and axial cuts increases the bending stiffness of the tubing member 100. Other embodiments may utilize one or more liners rather than a polymer filler material. For example, an inner liner may be disposed along the inner surface of the tubing member 100 and / or an outer liner may be disposed along the outer surface of the tubing member 100. In either case, the inner and outer liners do not fill the gaps in the tubing member 100. Such embodiments may advantageously leave the gaps in the transverse and axial cuts open and unblocked, which reduces the amount of resistance to bending and allows for lower bending stiffness.

[0045]

[0050] It should be understood that the above features are directed primarily to the distal section of tubular member 100. Similar features may be utilized in the more proximal section. However, because the more proximal section typically does not require the same bending flexibility, such section may be tailored to be more pushable and / or torquable and less bending flexible. Accordingly, the more proximal section may be modified via one or more of increasing the axial length of the rings, increasing the width of the beams, decreasing the size of the wedge gap, decreasing the depth of the axial cut, or increasing the number of beams between each pair of rings.

[0046] Example

[0051] A useful metric for comparing intravascular devices is the ratio of axial stiffness to bending stiffness. Axial stiffness and bending stiffness (i.e., bending stiffness) are typically expressed using different units. In the SI system, for example, axial stiffness is expressed in units of force per distance (e.g., Newtons per meter), while bending stiffness is typically expressed in units of force squared over distance (e.g., Newtons times squared meters). When using such units, a useful metric can be determined by comparing the ratio of axial stiffness to bending stiffness of a microfabricated structure and comparing that number to the ratio of axial stiffness to bending stiffness of a homogeneous material (not microfabricated but otherwise similar to the microfabricated structure). For example, the ratio of axial stiffness to bending stiffness of the microfabricated structure can be divided by the ratio of axial stiffness to bending stiffness of the homogeneous material, thereby providing a useful comparison ratio that indicates how the microfabricated structure compares to a reference homogeneous material. Such an overall ratio is unitless. This metric is referred to herein as the microfabricated-to-homogeneous ratio.

[0047]

[0052] Various catheter devices and materials were tested to measure the ratio of axial stiffness to bending stiffness. Tested materials included tubes of homogeneous rubber and plastic materials, including PEBAX® (polyether block amide), polyurethane, and others. Commercial catheter devices fabricated with sections of coiled and / or braided material were also tested. The fine-to-homogeneous ratios of commercially available catheters ranged from approximately 1 to 2.5. The highest fine-to-homogeneous ratio was found in one commercial catheter product with coiled and / or braided sections, measured at approximately 3.

[0048]

[0053] In comparison, tubing formed with a high press strength configuration, such as that shown in FIG. 5A, was also tested. While tubing formed from Nitinol was most preferred, tubing formed from other materials also performed satisfactorily. The high press strength configuration provided a significantly higher micro-machined to uniformity ratio than that of typical coil and / or braided arrangements. Tubing with a high press strength configuration had a micro-machined to uniformity ratio of greater than 3, and in some instances, significantly greater than 3. Some tests demonstrated a micro-machined to uniformity ratio of approximately 14. Some tests even demonstrated a micro-machined to uniformity ratio of up to 100 in the distal section of the tubing with a high degree of micro-machining.

[0049] Additional Terms and Definitions

[0054] Although embodiments of the present disclosure have been described in detail with reference to specific configurations, parameters, components, elements, etc., the description is illustrative and should not be construed as limiting the scope of the invention as set forth in the claims.

[0050]

[0055] Furthermore, it should be understood that for any given element of the components of the described embodiments, any of the possible alternatives listed for that element or component may generally be used individually or in combination with each other, unless otherwise specified implicitly or explicitly.

[0051]

[0056] Additionally, unless otherwise noted, numbers expressing quantities, components, distances, or other measurements used in the specification and claims should be understood as being optionally modified by the term "about" or its equivalents. When terms such as "about," "approximately," or "substantially" are used in connection with a stated quantity, value, or condition, they may also be construed to mean an amount, value, or condition that deviates by less than 20%, less than 10%, less than 5%, or less than 1% from the stated quantity, value, or condition. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0052]

[0057] The headings and sub-headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims.

[0053]

[0058] It should also be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" do not exclude plural referents unless the context clearly dictates otherwise. Thus, for example, embodiments referring to a singular referent (e.g., a "widget") may also include two or more such referents.

[0054]

[0059] It will be appreciated that the embodiments described herein may include properties, features (e.g., components, components, members, elements, parts, and / or portions) described in other embodiments described herein. Thus, various features of a given embodiment can be combined and / or incorporated with other embodiments of the present disclosure. Thus, the disclosure of a feature with respect to a particular embodiment of the present disclosure should not be construed as limiting the application or inclusion of said feature to the particular embodiment. Rather, it will be appreciated that other embodiments may also include such features.

[0055] Additional Exemplary Embodiments

[0060] Embodiments of the present disclosure may include, but are not necessarily limited to, the features listed in the following clauses.

[0056]

[0061] Embodiment 1: A microfabricated elongate tubular member (i.e., "device") for an intravascular device, the elongate tubular member extending along a longitudinal axis and including a plurality of circumferentially extending rings, each ring having an axial length; a plurality of transverse cuts respectively positioned between adjacent rings, each transverse cut extending transversely to the longitudinal axis of the tubular member; a plurality of axially extending beams each extending from one ring to another to connect adjacent rings; and a plurality of axial cuts aligned with the beams, each axial cut extending partially substantially axially into an adjacent ring such that a corresponding beam at least partially overlaps within the length of one or both of the adjacent rings connected by the corresponding beam.

[0057]

[0062] Embodiment 2: The device of embodiment 1, wherein the transverse cut is wedge-shaped.

[0058]

[0063] Embodiment 3: The apparatus of embodiment 2, wherein each transverse cut is narrower near the corresponding beam and widens as it extends circumferentially away from the corresponding beam.

[0059]

[0064] Embodiment 4: The device of any one of embodiments 1 to 3, wherein the axial cutting portion is wedge-shaped.

[0060]

[0065] Embodiment 5: The device of embodiment 4, wherein each axial cut is wider at the edge of the adjacent ring and tapers as it extends axially into the adjacent ring.

[0061]

[0066] Embodiment 6: The apparatus of any one of embodiments 1 to 5, wherein the tubular member has a two-beam configuration such that two beams extend between and connect each pair of adjacent rings.

[0062]

[0067] Embodiment 7: The apparatus of embodiment 7, wherein the pairs of beams between each pair of adjacent rings are circumferentially spaced apart by approximately 180 degrees.

[0063]

[0068] Embodiment 8: The apparatus of embodiment 6 or 7, wherein the two-beam configuration includes a rotational offset such that a given pair of adjacent rings is rotationally offset from the beams of the preceding and / or succeeding pair of adjacent rings.

[0064]

[0069] Embodiment 9: The device of embodiment 8, wherein the rotational offset is between about 5 degrees and about 90 degrees.

[0065]

[0070] Embodiment 10: The device of any one of embodiments 1 to 9, wherein the axial length of the ring becomes progressively shorter towards the distal end of the tubular member.

[0066]

[0071] Embodiment 11: The device of any one of embodiments 1 to 10, wherein the thickness of the beam becomes progressively smaller towards the distal end of the tubular member.

[0067]

[0072] Embodiment 12: The device of any one of embodiments 1 to 11, wherein in the distal section of the tubular member, the ring has a ratio of ring length to ring diameter of about 0.25 to 0.8, or about 0.35 to 0.65, or about 0.4 to 0.6.

[0068]

[0073] Embodiment 13: The device of any one of embodiments 1 to 12, wherein the tubular member is formed from nitinol.

[0069]

[0074] Embodiment 14: The device of any one of embodiments 1 to 13, wherein at least one section of the tubular member has a microfabrication-to-homogeneity ratio of at least about 3, or at least about 10, or at least about 20, or at least about 30, or at least about 40, or at least about 50, or at least about 60, or at least about 70, or at least about 80, or at least about 90.

[0070]

[0075] Embodiment 15: The device of any one of embodiments 1 to 14, wherein the tubular member is formed from one or more of polyetheretherketone (PEEK), stainless steel, or nitinol.

[0071]

[0076] Embodiment 16: The device of embodiment 15, wherein the tubular member is formed from nitinol.

[0072]

[0077] Embodiment 17: The device of any one of embodiments 1 to 16, further comprising a polymer applied to the tubular member to fill the transverse cuts and the axial cuts.

[0073]

[0078] Embodiment 18: The device of any one of embodiments 1 to 16, further comprising an inner liner and / or an outer liner attached to the tubular member.

[0074]

[0079] Embodiment 19: The device of embodiment 18, wherein the inner liner and / or the outer liner do not fill any of the lateral cuts or axial cuts.

[0075]

[0080] Embodiment 20: The device of any one of embodiments 1 to 19, wherein the tubular member is sized for use as an aspiration catheter in neurovascular applications.

[0076]

[0081] Embodiment 21: A microfabricated elongate tubular member for an intravascular device, the elongate tubular member extending along a longitudinal axis and including a plurality of circumferentially extending rings, each ring having an axial length; a plurality of axially extending beams each extending from one ring to another to connect adjacent rings; and a plurality of transverse cuts positioned between adjacent rings, each transverse cut extending transversely to the longitudinal axis of the tubular member, each transverse cut being narrower near a corresponding beam and widening as it extends circumferentially away from the corresponding beam.

[0077]

[0082] Embodiment 22: The tubular member of embodiment 21, wherein at least a portion of the transverse cut is wedge-shaped, and at least a portion of the transverse cut is narrower near the corresponding beam and widens as it extends circumferentially away from the corresponding beam.

[0078]

[0083] Embodiment 23: A microfabricated elongated tubular member for an intravascular device, the elongated tubular member extending along a longitudinal axis and comprising a plurality of circumferentially extending rings, each ring having an axial length; a plurality of axially extending beams each extending from one ring to another to connect adjacent rings; and a plurality of axial cuts aligned with the beams, each axial cut extending partially in a substantially axial direction into an adjacent ring, such that a corresponding beam at least partially overlaps within the length of one or both of the adjacent rings connected by the corresponding beam.

[0079]

[0084] Embodiment 24: The tubular member of embodiment 23, wherein at least a portion of the axial cut is wedge-shaped, and at least a portion of the axial cut is wider at the edge of the adjacent ring and narrows as it extends axially into the adjacent ring.

Claims

1. A microfabricated elongated tubular member for an intravascular device, the elongated tubular member extending along a longitudinal axis; and a plurality of circumferentially extending rings, each ring having an axial length; a plurality of transverse cuts each positioned between adjacent rings, each transverse cut extending transversely relative to the longitudinal axis of the tubular member; a plurality of axially extending beams each extending from one ring to another ring to connect adjacent rings; a plurality of axial cuts aligned with the beams, each axial cut extending partially axially into an adjacent ring such that a corresponding beam at least partially overlaps within the length of one or both of the adjacent rings connected by the corresponding beam; At least a portion of the axial cut is wedge-shaped; A microfabricated elongate tubular member for an intravascular device, wherein at least a portion of the axial cut is wider at the edges of the adjacent rings and tapers as it extends axially into the adjacent rings.

2. The tubular member of claim 1 , wherein at least a portion of the transverse cuts are wedge-shaped.

3. 3. The tubular member of claim 2, wherein at least some of the transverse cuts are narrower near the corresponding beam and widen as they extend circumferentially away from the corresponding beam.

4. 2. The tube member of claim 1, wherein the tube member has a two-beam configuration with a pair of beams between each pair of adjacent rings, the pair of beams between each pair of adjacent rings being circumferentially spaced 180 degrees apart.

5. 5. The tubular member of claim 4, wherein the two-beam configuration includes a rotational offset such that the beams between a given pair of adjacent rings are rotationally offset from the beams of the preceding and / or succeeding pairs of adjacent rings.

6. 6. The tubing of claim 5, wherein the rotational offset is between 5 degrees and 90 degrees.

7. 10. The tubular member of claim 1, wherein the axial length of the rings gradually decreases toward the distal end of the tubular member.

8. The tubular member of claim 1 , wherein the beam thickness gradually decreases toward the distal end of the tubular member.

9. The tubular member of claim 1, wherein in the distal section of the tubular member, the rings have a ratio of ring length to ring diameter of 0.25 to 0.

8.

10. The tubular member of claim 1 , wherein at least one section of the tubular member has a microfabrication-to-homogeneity ratio of at least 3.

11. The tubular member of claim 1 , wherein the tubular member is formed from one or more of polyetheretherketone (PEEK), stainless steel, or nitinol.

12. The tubular member of claim 1 further comprising a polymer applied to the tubular member to fill the transverse cut and the axial cut.

13. The tubing of claim 1 further comprising one or both of an inner liner or an outer liner.

14. The tubing of claim 13 , wherein the inner liner and the outer liner do not fill either the transverse cut or the axial cut.

15. A microfabricated elongated tubular member for an intravascular device, the elongated tubular member extending along a longitudinal axis; and a plurality of circumferentially extending rings, each ring having an axial length; a plurality of axially extending beams each extending from one ring to another ring so as to connect adjacent rings; a plurality of transverse cuts respectively positioned between adjacent rings, each transverse cut extending transversely to the longitudinal axis of the tubular member, each transverse cut being narrower near a corresponding beam and widening as it extends circumferentially away from the corresponding beam; the tubing member further includes one or both of an inner liner or an outer liner; The tubing member, wherein the inner liner and the outer liner do not fill the transverse cut.

16. 16. The tubular member of claim 15, wherein at least some of the transverse cuts are wedge-shaped, with at least some of the transverse cuts being narrower near the corresponding beam and widening as they extend circumferentially away from the corresponding beam.

17. A microfabricated elongated tubular member for an intravascular device, the elongated tubular member extending along a longitudinal axis; and a plurality of circumferentially extending rings, each ring having an axial length; a plurality of axially extending beams each extending from one ring to another ring so as to connect adjacent rings; a plurality of axial cuts aligned with the beams, each axial cut extending partially axially into an adjacent ring such that a corresponding beam at least partially overlaps within the length of one or both of the adjacent rings connected by the corresponding beam; a tubular member, wherein at least a portion of the axial cut is wedge-shaped, and wherein at least a portion of the axial cut is wider at the edge of the adjacent ring and narrows as it extends along the axial direction into the adjacent ring.

18. A pipe member as described in claim 1 or 17, wherein the angle of the axial cut portion is greater than 0 degrees but less than 35 degrees relative to the longitudinal axis.

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