Microfabricated 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. A tubular member includes a series of circumferentially extending rings interconnected 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 the adjoining rings such that the beam length is partially nested within the axial length of the adjoining rings. This increases the functional length of the beams to provide bending flexibility while still having sufficient ring structure to provide effective axial stiffness.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Patent Application Serial No. 17 / 493,265, filed October 4, 2021, entitled "Microfabricated Catheter Devices with High Axial Strength," which in turn claims priority and benefit to U.S. Provisional Patent Application Serial No. 63 / 087,410, filed October 5, 2020, also entitled "Microfabricated Catheter Devices with High Axial Strength," the entire contents of which are incorporated herein by reference. Background Technology

[0003] In the medical field, guidewires and catheters are frequently used to perform delicate procedures deep within the body's vascular system. Typically, a catheter is inserted into the patient's femoral, radial, carotid, or jugular vein, traversing the vascular system to reach the heart, brain, or other target anatomical structures. Usually, a guidewire is first guided to the target anatomical structure, followed by the passage of one or more catheters through the guidewire and guided to the desired location. Once in place, the catheter can be used to aspirate clots or other occlusions, or to deliver medications, stents, embolization devices, radiopaque dyes, or other devices or substances for patient treatment.

[0004] In many applications, such catheters must be guided through the tortuous bends and kinks of the vascular system to reach the target anatomical structures. Ideally, these catheters include design features that enable efficient navigation through such tortuous paths. For example, the catheter should be flexible enough to navigate the bends of the vascular system, but should also provide sufficient pushability (i.e., the ability to transfer axial force from the proximal portion to the distal portion) and torsion (i.e., the ability to transfer torque from the proximal portion to the distal portion).

[0005] For example, if the catheter lacks sufficient axial stiffness, the operator will have difficulty pushing the catheter forward through the vasculature. That is, the axial force applied by the operator at the proximal end can result in the catheter being compressed and "accordioned" axially, rather than being effectively transmitted to the distal end of the catheter. Designing the catheter to have higher axial stiffness can alleviate this problem. However, increasing the axial stiffness of the catheter leads to other problems (that interfere with the effectiveness of the catheter). For example, increasing the axial stiffness of the catheter also typically increases the bending stiffness of the catheter, which can be detrimental if there is insufficient bending flexibility remaining in the device.

[0006] Accordingly, there is a continuing need for catheter devices having features designed to allow for effective axial stiffness without unduly compromising desirable characteristics such as flexibility and torquability of the device. SUMMARY

[0007] The present disclosure describes a microfabricated intravascular device configured for high axial strength while also maintaining effective bending flexibility.

[0008] In one embodiment, the tube member includes a series of circumferentially extending rings that are interconnected by a series of axially extending beams. A plurality of transverse cuts separate and define the rings. The transverse cuts are disposed between adjacent rings and extend in a direction transverse to the longitudinal axis of the tube member, but not so as to completely cut through the tube member, thereby positioning the beams between the rings.

[0009] In some embodiments, at least a portion of the transverse cuts are wedge-shaped. For example, one or more of the transverse cuts can be narrower near the respective beam and then widen as they extend circumferentially away from the respective beam.

[0010] In some embodiments, a series of axial cuts are aligned with the beams and extend partially into the adjoining rings from the beams, such that the beam length is partially nested within the axial length of the adjoining rings. This increases the functional length of the beams to provide bending flexibility, while still providing sufficient ring structure to provide effective axial stiffness.

[0011] In some embodiments, at least a portion of the axial cuts are wedge-shaped. For example, one or more of the axial cuts can be wider at the edge of the adjoining ring and then narrow as they extend into the adjoining ring along the axial direction.

[0012] This summary is provided to introduce some concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. BRIEF DESCRIPTION OF DRAWINGS

[0013] The various objects, features, aspects and advantages of the present application will become evident to those skilled in the art and more fully understood from the following description, followed by the appended claims, taken in conjunction with the accompanying drawings. In the drawings, like reference numerals can be used to refer to similar or identical parts throughout each of the several views, and in which:

[0014] Figure 1 An example catheter device is shown that can be modified with the cutout patterns described herein to provide a catheter with high axial strength;

[0015] Figure 2A is a detailed view of a microfabricated distal section of a catheter with a traditional two-beam cutout pattern;

[0016] Figure 2B and 2C are detailed views of a microfabricated distal section of a catheter with a three-beam cutout pattern and a microfabricated distal section of a catheter with a single-beam cutout pattern, respectively;

[0017] Figure 3A and 3B schematically show how a microfabricated catheter section can compress and "fold" under axial load;

[0018] Figure 4 shows a microfabricated catheter section with relatively thick ring elements to enhance axial stiffness, but these ring elements concentrate bending forces in the axial beam elements; and

[0019] Figure 5A and 5B shows an example microfabricated catheter section with a cutout pattern that provides effective axial stiffness without excessively increasing bending stiffness, thereby providing a high axial-to-bending stiffness ratio. DETAILED DESCRIPTION

[0020] INTRODUCTION

[0021] Figure 1An example of a conventional catheter device 10 is shown, which can be improved by incorporating the unique high push strength cut pattern described below. The catheter device 10 includes a proximal section 40 and a distal section 50. A radiopaque marker 16 can be located near the distal end. A hub and / or port 42 can be located at the proximal end. Since the high push strength design has particular benefits in catheter applications, most of the examples described herein will relate to catheter devices. However, it should be understood that the same features can be applied to other microfabricated components of other intravascular devices (such as guide wires) in some embodiments.

[0022] At least a portion of the distal section 50 is microfabricated to have one or more cut patterns that are intended to increase the effectiveness of the device. Generally, such cut patterns focus on increasing the bend flexibility of the device while maintaining good torquability. However, as described below, improved cut patterns have now been designed that increase the bend flexibility of the device while optimizing pushability (i.e., optimizing axial stiffness).

[0023] While the improved cut patterns sacrifice some of the torquability of the conventional cut patterns, the enhanced pushability and improved ratio of axial stiffness to bending stiffness of the device provide more effective overall functionality, particularly in applications where axial stiffness can be more important than torquability, such as in many catheter applications. For example, unlike guide wires, catheters do not have a solid core and thus inherently lack good axial stiffness. Since catheters are typically guided by guide wires, the guide wires can be used to sub-select vessels and reach anatomical targets. Thus, in catheters, pushability is generally more important than torquability.

[0024] The length of the catheter 10 can vary depending on the needs of the particular application, but is generally in the range of about 125 cm to 175 cm. The microfabricated portion will likely vary depending on the needs of the particular application, but generally has a length of about 50 cm to 90 cm. The distal most section (e.g., about 10 cm to 30 cm distal most) generally has a higher degree of microfabrication so as to be (become) more flexible. Like the catheter length, the catheter diameter can vary depending on the needs of the application. Examples can range from about 2F to 10F, although sizes outside of this range can also be utilized where appropriate (e.g., outside of typical neuro and coronary applications). Aspiration catheters for neurovascular procedures are one exemplary application of the high push strength devices described herein.

[0025] The microfabricated sections of the catheter 10 include a plurality of cuts extending transverse to the longitudinal axis of the catheter to form "rings" and "beams". Rings are circumferentially extending annular structures, the tube connecting adjacent rings, beams are axially extending sections of the tube that are not cut. In this document, sections of the catheter 10 can be defined according to the number of beams disposed between each pair of consecutive rings.

[0026] Figures 2A-2C A conventional microfabricated construction is shown in order to describe general features and define general terminology. The improved features described further below can be applied to any of the conventional constructions shown in Figures 2A-2C .

[0027] For example, Figure 2A A conventional "two-beam section" 15 of microfabricated tube member is represented. 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. Figure 2B A "three-beam section" 20 is shown, in which three beams 22 are disposed between each set of adjacent rings 24. Figure 2C A "single-beam section" 30 is shown, in which a single beam 32 extends between and connects each pair of adjacent rings 34. While most of the examples described herein will refer to two-beam constructions, it should be understood that the same features can be applied to other embodiments having single-beam constructions or three-beam constructions, or even to constructions having other numbers of beams between each set of adjacent rings.

[0028] Figure 3A And 3B How a microfabricated catheter section can compress and "fold" under axial load is shown schematically. Figure 3A A side view of a conventional two-beam section (as in Figure 2A ) having beams 12 and rings 14 is shown. Figure 3B When an axial load (i.e. push) is applied, the rings 14 can flex slightly and absorb some of the axial load, rather than transferring it entirely to more distal sections of the device. This reduces the pushability of the device, and makes it more difficult for the operator to track the catheter through a guidewire and / or to get the catheter to the desired anatomical target.

[0029] One way to increase the axial stiffness of a device is to simply increase the length of the rings along the axial direction (this dimension is sometimes also referred to as the "thickness", "axial length", or "width" of the rings). Figure 4Embodiments are shown that increase the axial length of the ring 64. While increasing the axial length of the ring 64 does increase the axial stiffness of the device, there is a practical limit to how much the axial length of the ring 64 can be increased. For example, if the axial length of the ring 64 is increased too much relative to the dimensions of the beam 62, excessive bending stresses will be concentrated at the beam 62. At some point, without plastic deformation at the beam 62, the device will not bend sufficiently. Thus, simply increasing the ring size until the desired axial stiffness is achieved is not a practical option.

[0030] High push strength microfabricated segments

[0031] Figure 5A and Figure 5B Embodiments are shown of a high push strength cutout pattern that can be applied to a tube member and used in a catheter device, such as the device shown in Figure 1 The cutout pattern advantageously provides effective axial stiffness while still maintaining good bending flexibility. Furthermore, unlike simply enlarging the thickness of the ring, the illustrated construction allows for high relative axial stiffness without excessive stress concentration in the beam. Figure 5A An exemplary tube member 100 (e.g., a distal segment of a catheter) is shown, Figure 5B The same cutout pattern is shown if the tube member 100 were cut in half along the longitudinal axis and laid flat.

[0032] As shown, the elongate tube member 100 includes a series of circumferentially extending rings 114 that are connected together by a series of axially extending beams 112. The rings 114 have a length "L" in the axial direction. This dimension can sometimes be referred to as the ring "width," "axial length," or ring "thickness," but for consistency, it is generally referred to herein as length (or more specifically, axial length) as it is the dimension parallel to the longitudinal axis of the tube member 100. With respect to the beams 112, the "length" of the beams 112 will be used herein to refer to the dimension along the axial direction, while the "width" or "thickness" of the beams will be used herein to refer to the dimension along the circumference of the tube member 100.

[0033] The rings 114 are spaced apart by transverse cutouts 118, each of which extends in a direction transverse to the longitudinal axis of the tube member 100, but does not extend completely through the tube member 100. Thus, the tube member 100 is somewhat similar to the conventional construction shown in Figures 2A-2C The illustrated tube member 100 represents a two-beam segment in that it includes two beams 112 between each pair of adjacent rings 114. However, as noted above, other embodiments can include (some) constructions (e.g., a single-beam construction or a three-beam construction) that have a different number of beams between each pair of adjacent rings.

[0034] However, unlike Figures 2A-2C The conventional construction shown, and the embodiment shown, also include a series of axial cuts 116 aligned with beam 112. Each axial cut 116 begins along the edge of the corresponding beam 112 and extends partially into the adjacent ring 114 in a substantially axial direction, such that the corresponding beam 112 is partially “nested” within the axial length of the adjacent beam 112.

[0035] Figure 5A and Figure 5B Each of the beams 112 in the illustrated embodiment is associated with an axial cut 116 that extends into 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 only with axial cuts extending into 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 pipe member 100 may have some beams 112 associated with axial cuts 116, while other beams of the beams 112 are not associated with axial cuts 116.

[0036] Because a portion of beam 112 is nested within the axial length of ring 114, the result is that the beam structure per unit length of tube member 100 is more flexible compared to the same structure without axial notches 116. In other words, the notch pattern shown provides additional functional length to beam 112, thereby providing greater bending flexibility to the device, while still allowing ring 114 to be relatively thick along most of the device's circumference (i.e., having a relatively long axial length). Therefore, the entire structure is able to provide good axial stiffness without excessively increasing bending stiffness, resulting in a favorable axial stiffness to bending stiffness ratio for the device.

[0037] like Figure 5A and Figure 5B As shown, the transverse cut 118 can have a wedge shape. The wedge-shaped cut 118 advantageously provides additional spacing that allows the device to bend along the inside of the curve. Similarly, in embodiments where the gaps in the device are filled with a polymer material, as discussed further below, the wedge-shaped cut 118 provides additional space for the polymer, which is compressed toward the inside of the curve.

[0038] For example, at a given axial location of the tube member 100, the transverse cut 118 can be narrower near the beam 112 and then widen as it extends away from the beam 112. Starting from one of the beams 112 and extending around the circumference, the cut 118 will widen until it reaches an apex 119 and then will begin to narrow again while continuing to extend toward the opposite beam 112. As shown, the apex 119 can be located at a position equidistant from the two beams 112, however in other embodiments one or more of the transverse cuts 118 can be asymmetric and the apex 119 need not be equidistant from each beam 112.

[0039] The size and shape of the wedge-shaped transverse cuts 118 can vary. Generally, wider gaps provide greater spacing for tighter bending, but at the cost of reduced axial stiffness. Accordingly, for applications requiring greater bending flexibility, the wedge angle and / or gap size can be increased, or for applications requiring greater axial stiffness, the wedge angle and / or gap size can be decreased. Alternatively, the wedge angle and / or gap can be increased in regions of the device requiring greater flexibility and decreased in regions of the device requiring greater axial strength. In one non-limiting example, the wedge angle and / or gap size can increase at a distal section of the device relative to a proximal section of the device. In certain embodiments, the gap size of the apex 119 (i.e., the widest portion of the transverse cut 118) can be about 25% to about 100% of the length of the ring 114, or about 35% to about 75% of the length of the ring 114, at least at a distal section of the tube member 100. Additionally or alternatively, the wedge angle can gradually increase or decrease between one section and another such that the wedge angle gradually changes from a first section to a second section.

[0040] The wedge shape of the transverse cut 118 extends from the beam 112 at an angle “A” that can range from about 2 degrees to about 35 degrees, or about 5 degrees to about 25 degrees, or about 10 degrees to about 20 degrees. In other words, if an angle of 0 degrees represents a straight, perpendicular cut, the wedge-shaped cut 118 preferably has an angle greater than 0 degrees but less than about 35 degrees, more typically less than about 25 degrees or less than about 20 degrees.

[0041] 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, moving in a circumferentially perpendicular direction around the tube member 100 toward the other beam 112, the corresponding transverse cut 118 is angled away from the perpendicular line along both the proximally adjoining ring 114 and the distally adjoining ring 114. Other embodiments can include transverse cuts 118 that are angled away from the perpendicular line in only one direction (i.e., along the proximally adjoining ring only or along the distally adjoining ring only).

[0042] One or more axial cuts 116 can be wedge-shaped. As shown in FIG. 1, the axial cuts 116 can be wedge-shaped in that the axial cuts 116 are wider at the point where the cut begins along the edge of the ring and then narrows as it extends further along the axial direction into the adjoining ring. As with the wedge shape of the lateral cuts 118, the wedge shape of the axial cuts 116 can provide additional spacing that allows for more movement of the rings 114 relative to the beams 112, allowing the rings 114 to better curve toward each other along the inside of a curve when the tube member 100 is bent. If a straight axial cut (parallel to the longitudinal axis) had a cut angle of 0 degrees, the angle of the axial cuts 116 can be greater than 0 degrees but less than about 35 degrees, more typically less than about 25 degrees or less than about 20 degrees. Figure 5A and Figure 5B As shown, the axial cuts 116 can be slightly wider where the cut begins along the edge of the ring and then narrows as it extends further along the axial direction into the adjoining ring. As with the wedge shape of the lateral cuts 118, the wedge shape of the axial cuts 116 can provide additional spacing that allows for more movement of the rings 114 relative to the beams 112, allowing the rings 114 to better curve toward each other along the inside of a curve when the tube member 100 is bent. If a straight axial cut (parallel to the longitudinal axis) had a cut angle of 0 degrees, the angle of the axial cuts 116 can be greater than 0 degrees but less than about 35 degrees, more typically less than about 25 degrees or less than about 20 degrees.

[0043] At least for the distal section of the tube member 100, the axial cuts 116 can extend into the adjoining rings 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 rings 114. The more the axial cuts 116 extend into the rings 114, the greater the increased functional length of the associated beams 112. However, this is at the expense of some structure of the rings, so the deeper axial cuts 116 reduce some structure of the rings 114 at least in the particular portions of the rings 114 that coincide with the axial cuts 116 and the beams 112, which would otherwise contribute to axial stiffness. In some applications, the axial cuts 116 can extend further into the rings 114 to increase the length of the associated beams 112, and thus the flexibility of the tube member 100. In other applications, the axial cuts 116 can extend further into the rings 114 relative to one section of the device to another section of the device. For example, the axial cuts 116 can increase or decrease near the distal or proximal end of the device.

[0044] Correspondingly, the beam lengths can also increase or decrease in size. This can be a result of the length of the axial cuts 116 as described above. Alternatively or additionally, the beam lengths can vary in size by increasing or decreasing the length of the portion of the beams 112 between the respective pairs of rings 114, independent of the axial cuts 116. In some applications, one section of the tube member 100 can have relatively longer beam lengths than another section to impart different flexibility to the device at different portions of the device. Finally, the beam lengths can gradually vary from a first section to a second section, such that the beam lengths gradually increase or decrease between the two sections.

[0045] The beam width or beam thickness can also vary in size 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 can have a relatively greater beam width than a second section of the device. Further, the beam width can vary gradually such that the beam width of each beam 112 gradually increases between a first section and a second section.

[0046] The ring size can also vary depending on the overall size of the device and / or the section of the device. For example, at a distal section of the tube member 100, the rings 114 can 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 will utilize 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 will differ from one or more other sections of the device, such that one or more sections of the device have a greater axial strength relative to one or more other sections. In some embodiments, the ring axial length can vary gradually along the device, such that the ring size gradually increases or decreases from one section to another.

[0047] As shown, the beams 112 between each pair of adjacent rings 114 can be equally spaced circumferentially (e.g., 180 degrees apart in a dual beam configuration), however other embodiments can arrange the beams unequally spaced circumferentially. Multiple sets of beams 112 can also be rotationally offset from adjacent sets of beams 112. For example, a set of beams 112 between a given pair of adjacent rings can be rotationally offset from a set of beams of a previous and / or a subsequent pair of adjacent rings. In the illustrated embodiment, the rotational offset is 90 degrees. That is, a first pair of beams is disposed at a first rotational position, and then a next pair of beams is offset 90 degrees from the first pair of (beams) as one moves along the length of the tube member 100.

[0048] Other rotational offsets can be utilized. For example, the rotational offset can be about 5 degrees to about 90 degrees. Rotational offsets of less than 90 degrees provide a helical pattern that minimizes a preferred bending axis in the tube member 100. Alternatively, other beneficial “distributed” beam arrangements can also be used to avoid a preferred bending axis. These are described in greater detail in U.S. Patent Application Serial No. 16 / 616,139, entitled “Micro-Fabricated Medical Device Having a Non-Helical Cut Arrangement,” which is incorporated by reference herein in its entirety.

[0049] The tube member 100 can be formed of any material or combination of materials suitable for intravascular applications. Examples include polymeric materials such as polyether ether ketone (PEEK), other polymers capable of being formulated to have a similar modulus of elasticity range, stainless steel, or a super-elastic material such as nitinol. Preferred embodiments are formed of nitinol.

[0050] As briefly mentioned above, a polymeric material can be added to the tube member 100 to fill the gaps created by the transverse cuts 118 and the axial cuts 116 and to allow the tube member 100 to convey fluid. The polymeric material can include an elastomer, such as a polyether block amide and / or another similar polymer.

[0051] Another advantage of the described embodiments, as compared to conventional constructions, relates to the relatively low open gap space along the outer surface of the tube member 100. Because the improved cut pattern allows for increased axial length of the rings, less total outer surface area is occupied by the gaps. This means that the device is proportionally less dependent on polymeric material to maintain fluid seal integrity under pressure, and therefore is less likely to fail when conveying fluid under pressure.

[0052] Other embodiments can omit the polymeric material. For example, certain applications can not require the delivery or aspiration of fluid, and can feasibly utilize a device in which the gaps are not filled. In certain applications, it is beneficial to keep the gaps open because the addition of polymeric material to the transverse cuts and the axial cuts increases the bending stiffness of the tube member 100. Other embodiments can utilize one or more liners (rather than polymeric material) to fill the material. For example, an inner liner can be disposed along the inner surface of the tube member 100 and / or an outer liner can be disposed along the outer surface of the tube member 100. Either way, the inner liner and the outer liner do not fill the gaps of the tube member 100. Such embodiments can advantageously keep the gaps of the transverse cuts and the axial cuts open and unobstructed, which reduces the amount of resistance to bending, allowing for lower bending stiffness.

[0053] It should be appreciated that the foregoing features are primarily directed to the distal section of the tube member 100. Similar features can be used in the more proximal sections. However, the more proximal sections generally do not require the same bending flexibility, and thus such sections can be more tailored for pushability and / or torquability, and less for bending flexibility. Thus, the more proximal sections can 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 gaps of the wedges, decreasing the depth of the axial cuts, or increasing the number of beams between each pair of rings.

[0054] Examples

[0055] A useful metric for comparing intravascular devices is the ratio of axial stiffness to bending stiffness. Axial stiffness and bending stiffness (i.e., flexural rigidity) are typically reported using different units. For example, in the SI system, axial stiffness is typically reported in units of force per distance (e.g., Newtons per meter), while bending stiffness is typically reported in units of force times distance squared (e.g., Newtons times meters squared). When using such units, it is possible to determine a useful metric by comparing the ratio of axial stiffness to bending stiffness of a microfabricated structure to the ratio of axial stiffness to bending stiffness of a homogenous material (a material that is not microfabricated but otherwise similar to the microfabricated structure). For example, the ratio of axial stiffness to bending stiffness of a microfabricated structure can be divided by the ratio of axial stiffness to bending stiffness of a homogenous material to provide a useful comparison ratio that indicates how the microfabricated structure compares to the benchmark homogenous material. Such a total ratio is unitless. This metric is referred to herein as the microfabricated to homogenous ratio.

[0056] Various catheter devices and materials were tested to measure the ratio of axial stiffness to bending stiffness. The materials tested included tubes of homogenous rubber and plastic materials (including Pebax®, Hytrel®, polyurethane, etc.). Commercially available catheter devices formed of segments of coil and / or segments of braid material were also tested. The microfabricated to homogenous ratio of commercially available catheter tubes was generally in the range of about 1 to 2.5. The highest microfabricated to homogenous ratios were found in certain commercial catheter products having segments of coil and / or braid, with measured values of about 3.

[0057] In comparison to the above, tube members formed with high push strength configurations as shown in FIGS. 1-3 were also tested. Tube members formed of Nitinol were most preferred, although tube members formed of other materials also performed well. The high push strength configurations provided microfabricated to homogenous ratios that were significantly higher than the microfabricated to homogenous ratios of ordinary coil arrangements and / or braid arrangements. Tube members having high push strength configurations had microfabricated to homogenous ratios of greater than 3 (in some cases much greater than 3). Certain tests showed microfabricated to homogenous ratios of about 14. Certain tests even showed microfabricated to homogenous ratios of up to 100 at the distal section of the tube having a high degree of microfabrication. Figure 5A

[0058] Additional Terminology and Limitations

[0059] While certain embodiments of the disclosure have been described in detail with reference to particular arrangements, parameters, components, elements, and the like, it will be understood that the description is by way of illustration only and is not by way of limitation of the scope of the inventive subject matter.

[0060] ​​Furthermore, it should be understood that any given element or component of the embodiments described can also be optionally used, alone or in combination with any of the possible alternatives of the same, unless otherwise explicitly stated or limited by context.

[0061] Furthermore, as used in the specification and claims, the recital of amounts, ingredients, distances, or other measures by a term such as "about," "approximately," "substantially," or "essentially" shall be understood as an option to the recited term, unless otherwise indicated by context. When the term "about," "approximately," "substantially," or "essentially" is used in conjunction with a recited amount, value, or condition, it can be considered to mean amounts, values, or conditions that are within 20%, within 10%, within 5%, or within 1% of the stated amount, value, or condition. At the very least, and without intending to limit the application of the doctrine of equivalents to the claims, each numerical parameter should be construed in light of the number of significant figures and by applying ordinary rounding techniques.

[0062] Any headings and sub-headings provided herein are for organizational purposes only and are not meant to be used to limit the scope of the description or claims.

[0063] It will also be noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to an embodiment with "a component" can also include two or more such components.

[0064] It will also be understood that the embodiments described herein can include the properties, features (e.g., ingredients, components, members, elements, parts, and / or portions) described in other embodiments described herein. Accordingly, various features of a given embodiment can be combined with and / or incorporated into other embodiments of the disclosure. Thus, the disclosure of certain features in relation to one particular embodiment should not be construed to be limiting of the application or use of the features in relation to other embodiments. Rather, it will be understood that other embodiments can also include such features.

[0065] Additional Exemplary Embodiments

[0066] Embodiments of the disclosure can include, but are not necessarily limited to, the features recited in the following clauses:

[0067] Example 1 : A microfabricated elongated tube member (i.e., a "device") for an endovascular device, the elongated tube member extending along a longitudinal axis and comprising: a plurality of circumferentially extending rings, each ring having an axial length; a plurality of lateral cuts, each lateral cut positioned between adjacent rings, each lateral cut extending in a direction transverse to the longitudinal axis of the tube member; a plurality of axially extending beams, each beam extending from one ring to another ring to connect adjacent rings; and a plurality of axial cuts aligned with the beams, each axial cut extending partially into an adjoining ring in a substantially axial direction such that the respective beam is at least partially nested within the length of one or both of the adjoining rings connected by the respective beam.

[0068] Example 2: The device of Example 1, wherein the lateral cuts are wedge-shaped.

[0069] Example 3: The device of Example 2, wherein each lateral cut is narrower near the respective beam and widens as it extends circumferentially away from the respective beam.

[0070] Example 4: The device of any of Examples 1 -3, wherein the axial cuts are wedge-shaped.

[0071] Example 5: The device of Example 4, wherein each axial cut is wider at the edge of the adjoining ring and narrows as it extends into the adjoining ring along the axial direction.

[0072] Example 6: The device of any of Examples 1 -5, wherein the tube member has a dual beam configuration such that two beams extend between and connect each pair of adjacent rings.

[0073] Example 7: The device of Example 7, wherein the pair of beams between each pair of adjacent rings are circumferentially spaced apart by about 180 degrees.

[0074] Example 8: The device of Example 6 or Example 7, wherein the dual beam configuration includes a rotational offset such that the beams between a given pair of adjacent rings are rotationally offset from the beams of a preceding pair and / or a following pair of adjacent rings.

[0075] Example 9: The device of Example 8, wherein the rotational offset is from about 5 degrees to about 90 degrees.

[0076] Example 10: The device of any of Examples 1 -9, wherein the ring axial lengths gradually become shorter toward a distal end of the tube member.

[0077] Example 11 : The device of any of Examples 1 -10, wherein the beam thicknesses gradually become smaller toward a distal end of the tube member.

[0078] Example 12: The device of any of Examples 1-11, wherein, at 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.

[0079] Example 13: The device of any of Examples 1-12, wherein the tubular member is formed of nitinol.

[0080] Example 14: The device of any of Examples 1-13, wherein at least a 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.

[0081] Example 15: The device of any of Examples 1-14, wherein the tubular member is formed of one or more of polyether ether ketone (PEEK), stainless steel, or nitinol.

[0082] Example 16: The device of Example 15, wherein the tubular member is formed of nitinol.

[0083] Example 17: The device of any of Examples 1-16, further comprising a polymer applied to the tubular member to fill the transverse cuts and the axial cuts.

[0084] Example 18: The device of any of Examples 1-16, further comprising an inner liner and / or an outer liner attached to the tubular member.

[0085] Example 19: The device of Example 18, wherein the inner liner and / or the outer liner do not fill the transverse cuts or the axial cuts.

[0086] Example 20: The device of any of Examples 1-19, wherein the tubular member is sized for an aspiration catheter in neurovascular applications.

[0087] Example 21: A microfabricated elongate tubular member for an intravascular device, the elongate 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 beam extending from one ring to another ring to connect adjacent rings; and a plurality of transverse cuts, each transverse cut positioned between adjacent rings, each transverse cut extending in a direction transverse to the longitudinal axis of the tubular member, wherein each transverse cut is narrower proximate a respective beam and widens as it extends circumferentially away from the respective beam.

[0088] Embodiment 22: The tube member of Embodiment 21, wherein at least a portion of the transverse cut is wedge-shaped, and wherein at least a portion of the transverse cut is narrower near the respective beam and widens as it extends circumferentially away from the respective beam.

[0089] Embodiment 23: A microfabricated elongate tube member for an endovascular device, the elongate tube 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 beam extending from one ring to another ring to connect adjacent rings; and a plurality of axial cuts aligned with the beams, each axial cut extending partially into an adjoining ring in a substantially axial direction such that the respective beam is at least partially nested within the length of one or both of the adjoining rings connected by the respective beam.

[0090] Embodiment 24: The tube member of Embodiment 23, 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 adjoining ring and narrows as it extends into the adjoining ring along the axial direction.

Claims

1. A microfabricated elongated tubular member for an endovascular 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 transverse cuts, each transverse cut positioned between adjacent rings, each transverse cut extending in a direction transverse to the longitudinal axis of the tubular member; a plurality of axially extending beams, each beam extending from one ring to another ring to connect adjacent rings; and a plurality of axial cuts aligned with the beams, each axial cut extending partially into adjoining rings in a substantially axial direction such that the respective beam is at least partially nested within the length of one or both of the adjoining rings connected by the respective beam; wherein at least a portion of the axial cuts are wedge-shaped; at least a portion of the axial cuts are wider at the edges of the adjoining rings and narrow as they extend into the adjoining rings along the axial direction; and the axial cuts extend further into the adjoining rings on one section of the tubular member relative to another section of the tubular member.

2. The pipe member according to claim 1, wherein At least a portion of the transverse cuts are wedge-shaped.

3. The pipe member of claim 2, wherein, At least a portion of the transverse cuts are narrower near the respective beam and widen as they extend circumferentially away from the respective beam.

4. The pipe member of claim 1, wherein, The tubular member has a dual beam configuration such that there is a pair of beams between each pair of adjacent rings and the pair of beams between each pair of adjacent rings are circumferentially spaced 180 degrees apart.

5. The pipe member of claim 4, wherein, The dual beam configuration includes a rotational offset such that the beams between a given pair of adjacent rings are rotationally offset from the beams of a preceding pair and / or a following pair of adjacent rings.

6. The pipe member of claim 5, wherein, The rotational offset is 5 degrees to 90 degrees.

7. The pipe member of claim 1, wherein, Ring axial lengths gradually decrease toward a distal end of the tubular member.

8. The pipe member of claim 1, wherein, Beam thicknesses gradually decrease toward a distal end of the tubular member.

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

8.

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

11. The pipe member of claim 1, wherein, The tubular member is formed from one or more of polyether ether ketone (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 cuts and the axial cuts.

13. The tubular member of claim 1, further comprising one or both of an inner liner or an outer liner.

14. The pipe member of claim 13, wherein, The inner liner and the outer liner do not fill the transverse cuts or the axial cuts.

15. A microfabricated elongated tubular member for an endovascular 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 beam extending from one ring to another ring to connect adjacent rings; and a plurality of axial cuts aligned with the beams, each axial cut extending partially into adjoining rings in a substantially axial direction such that the respective beam is at least partially nested within the length of one or both of the adjoining rings connected by the respective beam; wherein at least a portion of the axial cut is wedge-shaped; at least a portion of the axial cut is wider at the edge of the abutted ring and narrows as it extends into the abutted ring along the axial direction; and the axial cut extends further into the abutted ring on one section of the tubular member relative to another section of the tubular member.

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