Embolic devices for occluding body lumens

Abstract

To provide an embolic device for placement in a body lumen.SOLUTION: An embolic device for placement in a body lumen includes: a first segment 110 having a first linear configuration when located inside a catheter, the first segment being configured to form a first three-dimensional structure 112 when outside the catheter, where the first three-dimensional structure defines a cavity 118; and a second segment 120 extending from the first segment, the second segment having a second linear configuration when located inside the catheter, the second segment being configured to form a second three-dimensional structure 122 when outside the catheter; where the cavity of the first three-dimensional structure is configured to accommodate at least a majority of the second three-dimensional structure.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The field of the disclosure relates to medical devices and methods for occluding body lumens, and more particularly, to medical devices and methods for occluding aneurysms. [Background technology]

[0002] Aneurysms are dilations of blood vessels that pose a health risk due to the potential for rupture, thrombosis or dissection. Rupture of an aneurysm in the brain can cause a stroke, while rupture of an aneurysm in the abdomen can cause shock. Cerebral aneurysms are usually discovered in patients as a result of a seizure or hemorrhage and can result in significant morbidity or mortality.

[0003] A variety of materials and devices have been used to treat aneurysms, including platinum and stainless steel microcoils, polyvinyl alcohol sponges (Ivalone), and other mechanical devices. For example, vascular occlusion devices are surgical instruments or implants that are placed into the vascular system of the body, usually via a catheter, to block the flow of blood through blood vessels that make up that part of the vascular system through the formation of embolisms, or to form such embolisms in aneurysms arising from blood vessels.

[0004] In some cases, there is a risk that known coil designs will migrate completely or partially from the aneurysm entrance zone into the supplying vessel. This risk is particularly high in wide-neck aneurysms, which are those in which the neck (entrance zone) has a diameter of at least 50% of the maximum diameter of the aneurysm. Summary of the Invention

[0005] An embolic device for placement in a body lumen includes a first segment having a first linear configuration when positioned within a catheter and configured to form a first three-dimensional structure when positioned outside the catheter, the first segment having a first linear configuration when positioned within the catheter and configured to form a first three-dimensional structure when positioned outside the catheter, the first segment having a first linear configuration when positioned within the catheter and configured to form a second three-dimensional structure when positioned outside the catheter, the cavity of the first three-dimensional structure configured to accommodate at least a majority of the second three-dimensional structure.

[0006] Optionally, the first three-dimensional structure comprises a first loop and the second three-dimensional structure comprises a second loop.

[0007] Optionally, a first curvature of the first loop of the first three-dimensional structure is less than a second curvature of the second loop of the second three-dimensional structure.

[0008] Optionally, the first segment has a first width and the second segment has a second width less than the first width, and / or the first segment has a first thickness and the second segment has a second thickness less than the first thickness.

[0009] Optionally, the first segment and the second segment form a unitary structure.

[0010] Optionally, the first segment and the second segment each include a braided segment.

[0011] Optionally, the first three-dimensional structure includes a first plurality of loops, where each loop of the first plurality of loops has a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof that increases or decreases along a length of a first segment forming the first three-dimensional structure, and / or the second three-dimensional structure includes a second plurality of loops, where each loop of the second plurality of loops has a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof that increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0012] Optionally, the first three-dimensional structure includes a first plurality of loops, where an angle between adjacent loops of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure, and / or the second three-dimensional structure includes a second plurality of loops, where an angle between adjacent loops of the second plurality of loops increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0013] Optionally, the first three-dimensional structure is configured to provide a scaffolding that spans the neck of the aneurysm.

[0014] Optionally, the first three-dimensional structure has at least two adjacent loops whose loop dimensions differ by no more than 20%, or no more than 10%, or no more than 5%.

[0015] Optionally, the first three-dimensional structure has at least two adjacent loops that form a first angle, and the second three-dimensional structure has at least two adjacent loops that form a second angle that is smaller than the first angle.

[0016] Optionally, the first segment and the second segment are portions of an elongate member having a distal end and a proximal end.

[0017] An embolic device for placement in a body lumen includes an elongated member having a proximal end and a distal end, the elongated member with a first segment configured to form a first three-dimensional structure, the first three-dimensional structure defining a cavity, and the elongated member includes a second segment configured to form a second three-dimensional structure within the cavity of the first three-dimensional structure.

[0018] Optionally, a first three-dimensional structure formed by a first segment of the elongate member includes a first loop, and a second three-dimensional structure formed by a second segment of the elongate member includes a second loop.

[0019] Optionally, a first curvature of the first loop of the first three-dimensional structure is less than a second curvature of the second loop of the second three-dimensional structure.

[0020] Optionally, the first segment has a first width and the second segment has a second width less than the first width, and / or the first segment has a first thickness and the second segment has a second thickness less than the first thickness.

[0021] Optionally, the first segment and the second segment form an integral structure.

[0022] Optionally, the first segment and the second segment each include a braided segment.

[0023] Optionally, the first three-dimensional structure includes a first plurality of loops, where each loop of the first plurality of loops has a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof that increases or decreases along a length of a first segment forming the first three-dimensional structure, and / or the second three-dimensional structure includes a second plurality of loops, where each loop of the second plurality of loops has a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof that increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0024] Optionally, the first three-dimensional structure includes a first plurality of loops, where an angle between adjacent loops of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure, and / or the second three-dimensional structure includes a second plurality of loops, where an angle between adjacent loops of the second plurality of loops increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0025] Optionally, the first three-dimensional structure is configured to provide a scaffolding that spans the neck of the aneurysm.

[0026] Optionally, the first three-dimensional structure has at least two adjacent loops whose loop dimensions differ by no more than 20%, or no more than 10%, or no more than 5%.

[0027] Optionally, the first three-dimensional structure has at least two adjacent loops that form a first angle, and the second three-dimensional structure has at least two adjacent loops that form a second angle that is smaller than the first angle.

[0028] A method for occluding a body lumen includes the steps of delivering a first segment of an embolic device into the body lumen, wherein the delivered first segment forms a first three-dimensional structure in the body lumen, the first three-dimensional structure defining a cavity, and delivering a second segment of the embolic device into the body lumen, wherein the second segment extends from the first segment and the delivered second segment forms a second three-dimensional structure, at least a majority of the second three-dimensional structure being contained within the cavity of the first three-dimensional structure.

[0029] Optionally, the first three-dimensional structure comprises a first loop and the second three-dimensional structure comprises a second loop.

[0030] Optionally, a first curvature of the first loop of the first three-dimensional structure is less than a second curvature of the second loop of the second three-dimensional structure.

[0031] Optionally, the first segment has a first width and the second segment has a second width less than the first width, and / or the first segment has a first thickness and the second segment has a second thickness less than the first thickness.

[0032] Optionally, the first segment and the second segment form a single configuration.

[0033] Optionally, the first segment and the second segment each include a braided segment.

[0034] Optionally, the first three-dimensional structure includes a first plurality of loops, where each loop of the first plurality of loops has a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof that increases or decreases along a length of a first segment forming the first three-dimensional structure, and / or the second three-dimensional structure includes a second plurality of loops, where each loop of the second plurality of loops has a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof that increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0035] Optionally, the first three-dimensional structure includes a first plurality of loops, where an angle between adjacent loops of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure, and / or the second three-dimensional structure includes a second plurality of loops, where an angle between adjacent loops of the second plurality of loops increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0036] Optionally, the first three-dimensional structure is configured to provide scaffolding across the neck of the aneurysm.

[0037] Optionally, the first three-dimensional structure has at least two loops whose loop dimensions do not differ by more than 20%, or more than 10%, or more than 5%.

[0038] Optionally, the first three-dimensional structure has at least two adjacent loops that form a first angle, and the second three-dimensional structure has at least two adjacent loops that form a second angle that is smaller than the first angle.

[0039] Optionally, the first segment and the second segment are portions of an elongate member having a distal end and a proximal end.

[0040] Other and further aspects and features will become apparent from a reading of the following detailed description. [Brief description of the drawings]

[0041] The drawings illustrate the design and utility of the embodiments, in which similar elements are referenced with common numerals. The drawings are not necessarily drawn to scale. To better understand how the above and other advantages and objects are obtained, a more particular description of the embodiments illustrated in the accompanying drawings will be rendered. The drawings depict only exemplary embodiments and therefore should not be considered as limiting the scope of the claims.

[0042] [Figure 1] FIG. 1 shows a medical apparatus having a catheter for delivering an embolic device. [Diagram 2] Figure 2A illustrates the medical device of Figure 1, particularly showing a distal segment of an embolic device being delivered from a catheter, and Figure 2B illustrates the medical device of Figure 1, particularly showing a proximal segment of an embolic device being delivered from a catheter. [Diagram 3]FIG. 3 shows the embolic device of FIG. 1, and in particular shows an embolic device having a first segment forming a first three-dimensional structure and a second segment forming a second three-dimensional structure within the first three-dimensional structure. [Figure 4] Figure 4A shows a first three-dimensional configuration of the embolic device of Figure 1. Figure 4B shows a second three-dimensional configuration of the embolic device of Figure 1. [Diagram 5] 5A and 5B show a prototype of the medical device of FIG. [Figure 6] Figure 6A shows an example of a loop layout of the first and second segments of the embolic device of Figure 1. Figure 6B shows another example of a loop layout of the first and second segments of the embolic device of Figure 1. [Figure 7] 7A and 7B illustrate a method of using the medical device of FIG. [Figure 8] FIG. 8 illustrates a method of delivering an embolic device into an aneurysm. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] Various embodiments will be described below with reference to the drawings. It should be noted that the drawings are not drawn to scale, and elements of similar structure or function are represented by the same reference numerals throughout the drawings. It should also be noted that the drawings are intended only to facilitate the description of the embodiments. They are not intended as an exhaustive description of the invention or as a limitation on the scope of the invention. Furthermore, the illustrated embodiments do not necessarily have all the aspects or advantages shown. An aspect or advantage described in connection with a particular embodiment is not necessarily limited to that embodiment, and may be implemented in any other embodiment, even if not so illustrated or not so explicitly described.

[0044] 1 illustrates a medical apparatus 10 having a catheter 20 for delivering an embolic device 100 into a body lumen. The catheter 20 has a distal end 22, a proximal end 24, and a catheter body 26 extending between the distal end 22 and the proximal end 24. The embolic device 100 is housed within a lumen 28 of the catheter 20. The catheter 20 further includes a shaft 30 disposed within the lumen 28 for pushing the embolic device 100 out of the lumen 28 of the catheter 20.

[0045] 1, embolic device 100 is made from an elongate member 102 having a distal end 104, a proximal end 106, and a body 108 extending between distal end 104 and proximal end 106. Embolic device 100 has a first segment 110 that has a first linear configuration when disposed within catheter 20. First segment 110 is configured to form a first three-dimensional structure 112 when first segment 110 is delivered outside catheter 20 (FIG. 2A).

[0046] As also shown in FIG. 1, the embolic device 100 has a second segment 120 extending from the first segment 110. The second segment 120 is proximal to the first segment 110. The second segment 120 has a second linear configuration when located inside the catheter 20. The second segment 120 is configured to form a second three-dimensional structure 122 when the second segment 120 is delivered outside the catheter 20 (FIG. 2B). In some embodiments, the first segment 110 and the segment 120 may be part of a single structure formed to include the first segment 110 and the second segment 120. In other embodiments, the first segment 110 and the second segment 120 may be separate components connected to each other via, for example, adhesives, welding, fusion, mechanical connectors, etc. In either case, the first segment 110 and the second segment 120 may be considered to have or form an integral configuration.

[0047] 2A , the first three-dimensional structure 112 defines a cavity 118 after the first segment 110 forming the first three-dimensional structure 112 is advanced from the catheter 20. Thus, after the first segment 110 is advanced from the catheter 20 into the body lumen, the first three-dimensional structure 112 provides the cavity 118 to accommodate a remaining portion of the embolic device 100 (e.g., at least a majority of the second segment 120 forming the second three-dimensional structure 122).

[0048] 3 illustrates the embolic device 100 of FIG. 1, and in particular illustrates the embolic device 100 having a first segment 110 forming a first three-dimensional structure 112 and a second segment 120 forming a second three-dimensional structure 122 within a cavity 118 of the first three-dimensional structure 112. As discussed above, the first segment 110 and the second segment 120 are portions of the elongate member 102.

[0049] As shown in FIG. 4A, the first three-dimensional structure 112 includes a series of seven loops 114. The loops 114 may be open loops as shown. Alternatively, one or more of the loops 114 may be closed loops. In other embodiments, the first three-dimensional structure 112 may have more than seven loops (e.g., eight loops, nine loops, ten loops, eleven loops, twelve loops, etc.) or less than seven loops (e.g., six loops, five loops, four loops, etc.). In the illustrated embodiment, the loops of the first three-dimensional structure 112 are connected by respective inflection points, which allows adjacent loops 114 to form opposite curvatures. In other embodiments, adjacent loops 114 of the first three-dimensional structure 112 may not form opposite curvatures. Additionally, in other embodiments, instead of loops, the first three-dimensional structure 112 may have other structural elements having shapes that are not loops.

[0050] As shown in FIG. 4B, the second three-dimensional structure 122 includes a series of seven loops 124. The loops 124 may be open loops as shown. Alternatively, one or more of the loops 124 may be closed loops. In other embodiments, the second three-dimensional structure 122 may have more than seven loops (e.g., eight loops, nine loops, ten loops, eleven loops, twelve loops, etc.) or less than seven loops (e.g., six loops, five loops, four loops, etc.). In the illustrated embodiment, the loops 124 of the second three-dimensional structure 122 are connected by respective inflection points, which allows adjacent loops 124 to form opposite curvatures. In other embodiments, adjacent loops 124 of the second three-dimensional structure 122 may not form opposite curvatures. Additionally, in other embodiments, instead of loops, the second three-dimensional structure 122 may have other structural elements having shapes that are not loops.

[0051] In some implementations, the curvature of one of the loops 114 of the first three-dimensional structure 112 may be less than the curvature of one of the loops 124 of the second three-dimensional structure 122. For example, in one implementation, the curvature of all of the loops 114 of the first three-dimensional structure 112 may be less than the curvature of all of the loops 124 of the second three-dimensional structure 122. In another implementation, the curvature of at least some of the loops 114 of the first three-dimensional structure 112 (e.g., a majority of the loops 114) may be less than the curvature of at least some of the loops 124 of the second three-dimensional structure 122 (e.g., a majority of the loops 124). As used herein, "curvature" may be defined as 1 / R, where R is the minimum radius of curvature associated with the curve.

[0052] In some embodiments, the first three-dimensional structure 112 has at least two loops (e.g., at least two adjacent loops) with respective loop dimensions that differ by no more than 20%, or no more than 10%, or no more than 5%. For example, in one embodiment, the first three-dimensional structure 112 can have loops 114 with the same loop dimension (e.g., loop width or diameter). In other embodiments, the first three-dimensional structure 112 can include loops 114 with respective loop dimensions that differ by more than 20%.

[0053] Additionally, in some embodiments, the loops 124 of the second three-dimensional structure 122 have respective loop dimensions that are smaller than the loop dimensions of the loops 114 of the first three-dimensional structure 112. This feature is advantageous because it assists the second segment 120 in forming the second three-dimensional structure 122 that is smaller than the first three-dimensional structure 112, thereby allowing the second three-dimensional structure 122 to fit within the first three-dimensional structure 112. In some cases, all of the loops 124 of the second three-dimensional structure 122 have respective loop dimensions that are smaller than all of the loop dimensions of the loops 114 of the first three-dimensional structure 112. In other aspects, at least half or a majority of the loops 124 of the second three-dimensional structure 122 have respective loop dimensions that are smaller than the loop dimensions of at least half or a majority of the loops 114 of the first three-dimensional structure 112.

[0054] In some embodiments, the first segment 110 of the embolic device 100 can have a first width and the second segment 120 of the embolic device 100 can have a second width that is less than the first width. Alternatively or additionally, the first segment 110 of the embolic device 100 can have a first thickness and the second segment 120 of the embolic device 100 can have a second thickness that is less than the first thickness. In one embodiment, the elongate member 102 can be of braided construction, and the narrower width and / or thinner thickness of the second segment 120 can be achieved by using fewer strands of fiber to form the braid of the second segment 120 compared to the number of strands of fiber used to form the braid of the first segment 110. Alternatively, the narrower width (or thinner thickness) of the second segment 120 can be achieved by cutting or scraping (e.g., using a laser cutter, grinder, etc.) a portion of the member used to form the second segment 120. As another alternative, the first and second segments 110, 120 can be formed from separate members having different respective cross-sectional dimensions. In such cases, the members can be secured together using, for example, adhesives, welding, fusion, mechanical couplers, etc. It should be noted that the terms "width" and "thickness" may refer to the longer and shorter dimensions of a cross-section, in some cases, such as a cross-section having a rectangular or oval shape. However, the use of either of these terms does not imply that the cross-section has an elongated shape. For example, the width or thickness of a cross-section may refer to the cross-sectional dimensions of a circular cross-section, a square cross-section, a hexagonal cross-section, a pentagonal cross-section, etc.

[0055] Also, in some embodiments, the first three-dimensional structure 112 has at least two adjacent loops 114 that form a first angle, and the second three-dimensional structure 122 has at least two adjacent loops 124 that form a second angle that is smaller than the first angle. This feature is advantageous because it helps the second segment 120 form a second three-dimensional structure 122 that is smaller than the first three-dimensional structure 112, thereby allowing the second three-dimensional structure 122 to fit within the first three-dimensional structure 112. In some embodiments, the angle between the two adjacent loops 114 of the first three-dimensional structure 112 may correspond to the dimensions of the aneurysm and / or the curvature of the aneurysm's wall. For example, the angle between the two adjacent loops 114 of the first three-dimensional structure 112 may be configured such that the two adjacent loops 114 engage the inner wall of the aneurysm when the first three-dimensional structure 112 is delivered into the aneurysm. In some cases, all adjacent loops 114 of the first three-dimensional structure 112 form corresponding angles that correspond to the dimensions of the aneurysm and / or the curvature of the aneurysm's wall. In other cases, at least half or a majority of the loops 114 of the first three-dimensional structure 112 form corresponding angles that correspond to the dimensions of the aneurysm and / or the curvature of the aneurysm's wall. The above features allow the first three-dimensional structure 112 to have a shape that closely corresponds to the profile of the inner wall of the aneurysm. Thus, the first three-dimensional structure 112 provides a frame that fits around the outer edge of the inner wall of the aneurysm.

[0056] In some embodiments, all angles between pairs of adjacent loops 114 of the first three-dimensional structure 112 are the same or do not differ by more than a certain percentage (e.g., 20%, 10%, 5%, etc.) In other embodiments, the angles between two or more pairs of adjacent loops 114 may differ by more than 20%.

[0057] Additionally, in some embodiments, the second segment 120 may have a progressive decrease in the angle between adjacent loops 124 from the distal end to the proximal end of the second segment 120. This allows the second segment 120 to form the second three-dimensional structure 122 from the "outside-in" to fill the outer space within the aneurysm before the inner space within the aneurysm. In other embodiments, the second segment 120 may have a progressive increase in the angle between adjacent loops 124 from the distal end to the proximal end of the second segment 120. This allows the second segment 120 to form the second three-dimensional structure 122 from the "inside-out" to fill the inner space within the aneurysm before the outer space within the aneurysm.

[0058] In some embodiments, the elongate members 102 forming the first segment 110 and the second segment 120 of the embolic device 100 may be braided. In such a case, each of the first segment 110 and the second segment 120 of the embolic device 100 includes a braided segment. In one embodiment, the first segment 110 and / or the second segment 120 may be formed with 24 braided strands of fiber. Alternatively, other numbers of strands of fiber may be used to form the elongate members. In another embodiment, the first segment 110 may be formed using more strands than the second segment 120, thereby creating a first segment 110 having a wider width and / or a thicker thickness than the second segment 120. In other embodiments, the number of strands may be changed without changing the cross-sectional width and / or thickness. In a further embodiment, the first segment 110 may be formed using a greater number of strands compared to the second segment 120, thereby making the first segment 110 stiffer compared to the second segment 120.

[0059] In other embodiments, the elongate member 102 that forms the first segment 110 and the second segment 120 of the embolic device 100 may be a coil. In such cases, the elongate member 102 has a primary shape that is a coil, and the coil can then be bent to form the desired secondary shape.

[0060] In further embodiments, the elongate members 102 that form the first segment 110 and the second segment 120 of the embolic device 100 may be solid continuous members. In such cases, the solid continuous member has a primary shape that is straight, and then the solid continuous member may be bent to form the desired secondary shape.

[0061] In one or more embodiments described herein, the combined length of the first and second segments 110, 120 may be between 15 cm and 50 cm, or between 25 cm and 45 cm, or between 30 cm and 40 cm. In other embodiments, the combined length of the first and second segments 110, 120 may be less than 15 cm or greater than 40 cm.

[0062] Also, in one or more embodiments described herein, the elongated member 102 having the first and second segments 110, 120 may be made from any suitable material. By way of non-limiting example, the elongated member 102 of the embolic device 100 may be made from Nitinol, AuPt, stainless steel, or other metals or alloys.

[0063] Figures 5A and 5B show a prototype of the medical device 10 of Figure 1. As shown in Figure 5A, a catheter 20 delivers a first segment 110 that forms a first three-dimensional structure 112, followed by a second segment 120 that forms a second three-dimensional structure 122 inside the cavity of the first three-dimensional structure 112. Figure 5B shows the same medical device 10 as Figure 5A, with the second three-dimensional structure 122 positioned outside the first three-dimensional structure 112 and stretched open to reveal the loops 114 of the first segment 110 and the loops 124 of the second segment 120.

[0064] FIG. 6A illustrates an example of a loop layout for the first and second segments 110, 120 of the embolic device 100 of FIG. 1. In the illustrated example, the loops 114, 124 of each of the first and second segments 110, 120 are shown in a plan view, without showing the relative angles between the loops. This allows the relative sizes of the loops 114, 124 to be visualized. As shown in this example, the first segment 110 has seven loops, and the second segment 120 has seven loops. In other embodiments, the number of loops may be different. For example, in other embodiments, the first segment 110 may have more or fewer loops compared to the second segment 120. In one example, the size of each loop 124 of the second segment 120 decreases from distal to proximal. This allows the second segment 120 to gradually fill the aneurysm from the outer edge of the aneurysm toward the inner core or center of the aneurysm as the second segment 120 is pushed out of the catheter 20. In other embodiments, the size of each loop 124 of the second segment 120 increases from distal to proximal, allowing the second segment 120 to gradually fill the aneurysm from the inner core or center of the aneurysm toward the outer edge as the second segment 120 is pushed out of the catheter 20. In further embodiments, the size of each loop 124 of the second segment 120 may be the same. In yet other embodiments, the size of the loops 124 of the second segment 120 may repeatedly vary up and down or have a random pattern.

[0065] In the above example, the size of the first loop of the second segment 120 is the same as or smaller than the size of the last loop in the first segment 110. In other examples, the size of the first loop in the second segment 120 may be larger than the size of the last loop in the first segment 110. For example, as shown in FIG. 6B, the first segment 110 can include loops 114 having respective loop widths that decrease from 0.85D to 0.55D (D can be a reference dimension), and the second segment 120 can include loops 124 having respective loop widths that decrease from 0.75D to 0.35D. This configuration is advantageous because the larger sized loops of the later segment (e.g., loops having a dimension of 0.75D in this example) can improve filling by pushing the previous loops of the previous segment (already delivered) (e.g., loops 0.65D, 0.55D in this example) to the outer edge of the aneurysm. In other embodiments, the embolic device 100 can include additional segments. For example, proximal to the second segment 120 there may be a third segment that may include an initial loop having a dimension of 0.55D. Thus, as the segments of elongate member 102 are delivered, they form respective filling structures that press the previously delivered structure or structures radially toward the outer edge of the aneurysm.

[0066] Although the embolic device 100 has been described as having a first segment 110 and a second segment 120, it should be noted that the embolic device 100 is not limited to having only two segments. In other embodiments, the embolic device 100 can have more than two segments. For example, in other embodiments, the embolic device 100 can have a third segment, a fourth segment, a fifth segment, etc. In some embodiments, each previous segment forms a filling structure that allows the subsequent segment to be accommodated. This allows different three-dimensional structures to be progressively delivered into the aneurysm in a nested configuration to fill the aneurysm from the outer edge toward the center. In some embodiments, the first segment 110 can have a first set of loops, the second segment 120 can have a second set of loops, and the third segment can have a third set of loops. The first set of loops can have loop widths that are the same size or that decrease in size from distal to proximal. Similarly, the second set of loops can have loop widths that are the same size or that decrease in size from distal to proximal. Also, the third set of loops can have loop widths that are the same size or that decrease in size from distal to proximal. Additionally, in some embodiments, the first (i.e., distal) loop of the subsequent segment can have a width that is less than the width of the last (i.e., proximal) loop of the previous segment. Alternatively, in other embodiments, the first (i.e., distal) loop of the subsequent segment can have a width that is greater than the width of the last (i.e., proximal) loop of the previous segment.

[0067] In one or more embodiments described herein, the embolic device 100 can optionally further include a distal loop at a distal end of the first segment 110, the distal loop having a diameter that is 75% or less than the diameter of the loop proximal to the distal loop. In some embodiments, the distal loop can be formed by the first segment 110. As used herein, the "diameter" of a loop does not necessarily mean that the loop is circular, and the term "diameter" can refer to the width of a loop whether or not it is circular in shape. For example, the diameter of a loop can refer to the maximum width of the loop in some cases.

[0068] Additionally, in one or more embodiments described herein, embolic device 100 can optionally further include a distal coil at a distal end of embolic device 100. In one embodiment, if first segment 110 is formed from a braid, the distal coil can be formed from one or more strands of the braid used to form first segment 110. In another embodiment, the distal coil can be a separate coil that is attached to the distal end of first segment 110.

[0069] Additionally, in one or more embodiments described herein, the embolic device 100 can optionally further include a proximal coil at a proximal end of the embolic device 100. In one embodiment, if the second segment 120 is formed from a braid, the proximal coil can be formed from one or more strands of the braid used to form the second segment 120. In another embodiment, the proximal coil can be a separate coil that is attached to the proximal end of the second segment 120. The proximal coil can be advantageous because it can provide a stiffness transition from the second segment 120 to the shaft 30.

[0070] Also, in one or more embodiments described herein, the second segment 120 of the embolic device 100 can have a different stiffness (e.g., bending stiffness and / or axial stiffness) than the stiffness (e.g., bending stiffness and / or axial stiffness) of the first segment 110 of the embolic device 100. In some embodiments, the second segment 120 can have a column strength different from the column strength of the first segment 110. For example, the column strength of the second segment 120 can be higher than the column strength of the first segment 110. This is advantageous because it allows the embolic device 100 to be pushed distally inside the catheter 20 without buckling. The relative difference in column strength and / or stiffness can be achieved between the first and second segments 110, 120 by varying cross-sectional dimensions, using metallurgical heat treatment conditions, and / or by varying the number of strands in the braided structure.

[0071] Also, in one or more embodiments described herein, when the member 102 forming the first and second segments 110, 120 is a braided structure, the braid angle of the strands along the length of the member 102 can be varied to vary the stiffness along the length of the member 102. For example, in some embodiments, the first segment 110 and the second segment 120 can have the same number of strands, but the braid angle of the strands of the first segment 110 (e.g., the angle the strands make with respect to the longitudinal axis of the member 102) can be greater than the braid angle of the strands of the second segment 120, thereby making the first segment 110 stiffer than the second segment 120. In other embodiments, the braid angle of the strands in the second segment 120 can be greater than the braid angle of the strands in the first segment 110, thereby making the second segment 120 stiffer than the first segment 110. Additionally, in some embodiments, the braid angle of the strands along the length of member 102 may vary gradually.

[0072] Further, in some embodiments, the first three-dimensional structure 112 comprises a first plurality of loops 114, where the loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof, of each of the first plurality of loops 114 increases or decreases along the length of the first segment 110 forming the first three-dimensional structure 112, and / or the second three-dimensional structure 122 comprises a second plurality of loops 124, where the loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof, of each of the second plurality of loops 124 increases or decreases along the length of the second segment 120 forming the second three-dimensional structure 122.

[0073] Further, in some embodiments, the first three-dimensional structure 112 includes a first plurality of loops 114, where the angle between adjacent loops of the first plurality of loops 114 increases or decreases along the length of the first segment 110 forming the first three-dimensional structure 112, and / or the second three-dimensional structure 122 includes a second plurality of loops 124, where the angle between adjacent loops of the second plurality of loops 124 increases or decreases along the length of the second segment 120 forming the second three-dimensional structure 122.

[0074] Additionally, it should be noted that embolic device 100 is not limited to the examples described herein, and embolic device 100 can have other configurations in other embodiments. For example, in other embodiments, first segment 110 of embolic device 100 can have other curved shapes so long as it forms a framework to define a cavity therein. Also, in other embodiments, second segment 120 of embolic device 100 can have other curved shapes so long as it provides a central filling effect to fill a central cavity defined by the first three-dimensional structure formed by first segment 110.

[0075] A variety of techniques can be used to form the embolic device 100. In some embodiments, the elongated member 102 can be wrapped around one or more mandrels to form a desired shape. The one or more mandrels can include a number of struts configured so that the elongated member 102 can be wrapped around them. The size of the struts determines the loop size of the loops that are formed. Also, the relative orientation of the struts determines the relative angle between the loops that are formed. After the elongated member 102 is wrapped around the one or more mandrels, the elongated member 102 can undergo chemical and / or heat treatments to set the shape of the elongated member 102. Other techniques for shaping the elongated member can be used in other embodiments to form the embolic device 100.

[0076] 7A and 7B illustrate a method of using the medical device 10 of FIG. 1 to treat an aneurysm 700. In using the medical device 10, the catheter 20 is first inserted through an incision into a patient's blood vessel 702. The catheter 20 is then advanced distally until the distal end 22 of the catheter 20 reaches the aneurysm.

[0077] In some embodiments, the catheter 20 is steerable. For example, the catheter 20 can include one or more steering wires configured to steer the distal end 22 of the catheter 20 in one or more directions. In other embodiments, the catheter 20 may not be steerable. Instead, a guidewire can be used to access the target site. The catheter 20 can then be placed over the guidewire and advanced distally using the guidewire. In such cases, the catheter 20 can include a separate channel to accommodate the guidewire.

[0078] After the distal end 22 of the catheter 20 is desirably positioned, the shaft 30 (shown in FIG. 1 ) is advanced to push the embolic device 100 distally until the first segment 110 of the embolic device 100 is outside the catheter 20 ( FIG. 7A ). As shown, the first segment 110 forms a first three-dimensional structure 112 when the first segment 110 is unconstrained outside the catheter 20. The first three-dimensional structure 112 has a shape corresponding to the inner wall of the aneurysm such that the first three-dimensional structure 112 is positioned immediately adjacent to the wall of the aneurysm (e.g., abutting the wall of the aneurysm or within 0.5 mm of the wall of the aneurysm). The first three-dimensional structure 112, shown diagrammatically in dashed lines in FIG. 7A , provides a frame that defines a cavity 118 for receiving the second segment 120 of the embolic device 100. As shown, the first three-dimensional structure 112 also provides a scaffolding that spans the neck 704 of the aneurysm 700 , which helps accommodate the second three-dimensional structure 122 that is delivered within the cavity 118 .

[0079] The shaft 30 can then be advanced further to push the second segment 120 of the embolic device 100 until the second segment 120 exits the catheter 20 (FIG. 7B). As shown, when the second segment 120 is unconstrained outside the catheter 20, the second segment 120 forms a second three-dimensional structure 122. The second three-dimensional structure 122 has a shape capable of filling at least a portion of the space within the cavity 118 defined by the first three-dimensional structure 112. As shown, the scaffolding provided by the first three-dimensional structure 112 across the neck 704 of the aneurysm prevents the second three-dimensional structure 122 from detaching or falling out of the cavity 118 of the first three-dimensional structure 112 and out of the aneurysm.

[0080] In some embodiments, the distal end of the shaft 30 abuts the proximal end of the second segment 120 and is not mechanically attached to the proximal end of the second segment 120. In such cases, the second segment 120 becomes decoupled from the remainder of the medical device 10 as soon as the proximal end of the second segment 120 is pushed out of the catheter 20. In other embodiments, the distal end of the shaft 30 can be mechanically connected to the proximal end of the second segment 120, such as via a mechanical connector operable to decouple the proximal end of the second segment 120 from the shaft 30. In further embodiments, the distal end of the shaft 30 can be mechanically connected to the proximal end of the second segment 120 via a degradable link, such as a link that can be degraded in response to the application of an electric current. Mechanical connectors and degradable links are well known in the art and will not be described in further detail.

[0081] In some embodiments, multiple embolic devices 100 can have different respective lengths. In such cases, before selecting one of the embolic devices 100 to treat the aneurysm, the physician can measure the size of the aneurysm to be treated. For example, the physician can take measurements using one or more images of the aneurysm to determine the size of the aneurysm. The size may be a cross-sectional dimension of the aneurysm, a cross-sectional area of ​​the aneurysm, a volume of the aneurysm, etc. After determining the size of the aneurysm, one of the embolic devices 100 can be selected based on the size of the aneurysm. For example, a longer embolic device 100 can be selected to occlude a larger aneurysm.

[0082] As shown in the above examples, the embolic device 100 is advantageous because it can accomplish two purposes with the same device: (1) forming a frame at the outer edge of the aneurysm that provides a scaffolding spanning the neck of the aneurysm, and (2) filling the central space of the aneurysm while ensuring that the filling material is contained within the aneurysm by the frame. The embolic device 100 can be used to treat all types of aneurysms, including aneurysms with wide necks. The embolic device 100 is also advantageous because it does not require multiple deliveries of separate embolic devices. In particular, the same embolic device 100 serves the purpose of both frame formation and filling, eliminating the need to provide multiple deliveries (e.g., one delivery for frame formation and another delivery of another device or devices for filling). Furthermore, the features of the embolic device 100 described herein are advantageous because they enable delivery of the elongated member into the aneurysm by a progressive nesting action configured such that different portions of the elongated member 102 form different layers of "nesting" as the elongated member 102 is delivered outside of a delivery catheter. This results in the aneurysm being substantially and / or securely filled by the embolic device 100.

[0083] 8 illustrates a method 800 for occluding a body lumen. The method 800 includes delivering a first segment of an embolic device into the body lumen, where the delivered first segment forms a first three-dimensional structure within the body lumen, where the first three-dimensional structure defines a cavity (item 802). The method 800 also includes delivering a second segment of the embolic device into the body lumen, where the second segment extends from the first segment, where the delivered second segment forms a second three-dimensional structure, where at least a majority of the second three-dimensional structure is contained within the cavity of the first three-dimensional structure (item 804).

[0084] In some embodiments, the embolic device in the method 800 may be the embolic device 100 described herein.

[0085] Optionally, in method 800, the first three-dimensional structure comprises a first loop and the second three-dimensional structure comprises a second loop.

[0086] Optionally, in the method 800, a first curvature of the first loop of the first three-dimensional structure is less than a second curvature of the second loop of the second three-dimensional structure.

[0087] Optionally, in method 800, the first segment has a first width and the second segment has a second width that is smaller than the first width, and / or the first segment has a first thickness and the second segment has a second thickness that is smaller than the first thickness.

[0088] Optionally, in the method 800, the first segment and the second segment form a unitary structure.

[0089] Optionally, in the method 800, the first segment and the second segment each include a braided segment.

[0090] Optionally, in method 800, the first three-dimensional structure includes a first plurality of loops, wherein a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof, of each loop of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure, and / or the second three-dimensional structure includes a second plurality of loops, wherein a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof, of each loop of the second plurality of loops increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0091] Optionally, in method 800, the first three-dimensional structure includes a first plurality of loops, and an angle between adjacent loops of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure, and / or the second three-dimensional structure includes a second plurality of loops, and an angle between adjacent loops of the second plurality of loops increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0092] Optionally, in method 800, the first three-dimensional structure provides a scaffolding that spans the neck of the aneurysm.

[0093] Optionally, in method 800, the first three-dimensional structure comprises at least two adjacent loops, the respective loop dimensions differing by no more than 20%, or no more than 10%, or no more than 5%.

[0094] Optionally, in method 800, the first three-dimensional structure has at least two adjacent loops that form a first angle, and the second three-dimensional structure has at least two adjacent loops that form a second angle that is smaller than the first angle.

[0095] Optionally, in the method 800, the first segment and the second segment are portions of an elongate member having a distal end and a proximal end.

[0096] The following items are exemplary features of the embodiments described herein. Each item may be an embodiment in itself or a part of an embodiment. One or more items described below may be combined with one or more other items in an embodiment.

[0097] Item 1: An embolic device for placement in a body lumen includes a first segment having a first linear configuration when located within a catheter and configured to form a first three-dimensional structure when exterior to the catheter, the first segment defining a cavity; and a second segment extending from the first segment, having a second linear configuration when located within the catheter and configured to form a second three-dimensional structure when exterior to the catheter, the cavity of the first three-dimensional structure configured to accommodate at least a majority of the second three-dimensional structure.

[0098] Item 2: the first three-dimensional structure comprises a first loop and the second three-dimensional structure comprises a second loop.

[0099] Item 3: The first curvature of the first loop of the first three-dimensional structure is smaller than the second curvature of the second loop of the second three-dimensional structure.

[0100] Item 4: The first segment has a first width and the second segment has a second width smaller than the first width, and / or the first segment has a first thickness and the second segment has a second thickness smaller than the first thickness.

[0101] Item 5: The first segment and the second segment form an integral structure.

[0102] Item 6: The first segment and the second segment each include a braided segment.

[0103] Item 7: The first three-dimensional structure comprises a first plurality of loops, wherein a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof, of each loop of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure; and / or the second three-dimensional structure comprises a second plurality of loops, wherein a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof, of each loop of the second plurality of loops increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0104] Item 8: The first three-dimensional structure comprises a first plurality of loops, wherein an angle between adjacent loops of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure, and / or the second three-dimensional structure comprises a second plurality of loops, wherein an angle between adjacent loops of the second plurality of loops increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0105] Item 9: The first three-dimensional structure has at least two adjacent loops that form a first angle, and the second three-dimensional structure has at least two adjacent loops that form a second angle that is smaller than the first angle.

[0106] Item 10: The first segment and the second segment are portions of an elongate member having a distal end and a proximal end.

[0107] Item 11: An embolic device for placement in a body lumen comprises an elongate member having a proximal end and a distal end, the elongate member including a first segment configured to form a first three-dimensional structure, the first three-dimensional structure defining a cavity, and the elongate member including a second segment configured to form a second three-dimensional structure within the cavity of the first three-dimensional structure.

[0108] Item 12: A first three-dimensional structure formed by a first segment of the elongate member includes a first loop, and a second three-dimensional structure formed by a second segment of the elongate member includes a second loop.

[0109] Item 13: The first curvature of the first loop of the first three-dimensional structure is smaller than the second curvature of the second loop of the second three-dimensional structure.

[0110] Item 14: The first segment has a first width and the second segment has a second width smaller than the first width, and / or the first segment has a first thickness and the second segment has a second thickness smaller than the first thickness.

[0111] Item 15: The first segment and the second segment form a unitary structure.

[0112] Item 16: The first segment and the second segment each include a braided segment.

[0113] Item 17: The first three-dimensional structure comprises a first plurality of loops, wherein a loop width, loop curvature, braid width, braid thickness, braid angle or any combination thereof of each loop of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure; and / or the second three-dimensional structure comprises a second plurality of loops, wherein a loop width, loop curvature, braid width, braid thickness, braid angle or any combination thereof of each loop of the second plurality of loops increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0114] Item 18: The first three-dimensional structure comprises a first plurality of loops, wherein an angle between adjacent loops of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure, and / or the second three-dimensional structure comprises a second plurality of loops, wherein an angle between adjacent loops of the second plurality of loops increases or decreases along a length of a second segment forming the second three-dimensional structure.

[0115] Item 19: The first three-dimensional structure has at least two adjacent loops that form a first angle, and the second three-dimensional structure has at least two adjacent loops that form a second angle that is smaller than the first angle.

[0116] Item 20: A method for occluding a body lumen includes the steps of delivering a first segment of an embolic device into the body lumen, wherein the delivered first segment forms a first three-dimensional structure in the body lumen, the first three-dimensional structure defining a cavity, and delivering a second segment of the embolic device into the body lumen, wherein the second segment extends from the first segment and the delivered second segment forms a second three-dimensional structure, at least a majority of the second three-dimensional structure being contained within the cavity of the first three-dimensional structure.

[0117] Item 21: The first three-dimensional structure comprises a first loop and the second three-dimensional structure comprises a second loop.

[0118] Item 22: The first curvature of the first loop of the first three-dimensional structure is smaller than the second curvature of the second loop of the second three-dimensional structure.

[0119] Item 23: The first segment has a first width and the second segment has a second width smaller than the first width, and / or the first segment has a first thickness and the second segment has a second thickness smaller than the first thickness.

[0120] Item 24: The first segment and the second segment form an integral structure.

[0121] Item 25: The first segment and the second segment each include a braided segment.

[0122] Item 26: The first three-dimensional structure provides a scaffold that spans the neck of the aneurysm.

[0123] Item 27: The first three-dimensional structure has at least two adjacent loops, the respective loop dimensions of which do not differ by more than 20%, or do not differ by more than 10%, or do not differ by more than 5%.

[0124] Item 28: The first three-dimensional structure has at least two adjacent loops that form a first angle, and the second three-dimensional structure has at least two adjacent loops that form a second angle that is smaller than the first angle.

[0125] Item 29: The first segment and the second segment are portions of an elongate member having a distal end and a proximal end.

Claims

1. 1. An embolic device for placement in a body lumen, comprising: a first segment having a first linear configuration when located within the catheter, the first segment configured to form a first three-dimensional structure when exterior to the catheter that defines a cavity; a second segment extending from the first segment, the second segment having a second linear configuration when located within the catheter and configured to form a second three-dimensional structure when external to the catheter; An embolic device, wherein a cavity of the first three-dimensional structure is configured to accommodate at least a majority of the second three-dimensional structure.

2. 2. The embolic device of claim 1, An embolic device, wherein the first three-dimensional structure comprises a first loop and the second three-dimensional structure comprises a second loop.

3. 3. The embolic device of claim 2, An embolic device, wherein a first curvature of a first loop of the first three-dimensional structure is less than a second curvature of a second loop of the second three-dimensional structure.

4. The embolic device according to any one of claims 1 to 3, the first segment has a first width and the second segment has a second width that is smaller than the first width; and / or An embolic device, wherein the first segment has a first thickness and the second segment has a second thickness that is less than the first thickness.

5. The embolic device according to any one of claims 1 to 3, An embolic device, wherein the first segment and the second segment form a unitary construction.

6. The embolic device according to any one of claims 1 to 5, An embolic device, wherein the first segment and the second segment each comprise a braided segment.

7. 2. The embolic device of claim 1, the first three-dimensional structure comprises a first plurality of loops, wherein a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof, of each loop of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure; and / or An embolic device, characterized in that the second three-dimensional structure includes a second plurality of loops, and the loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof, of each loop of the second plurality of loops increases or decreases along the length of a second segment forming the second three-dimensional structure.

8. 2. The embolic device of claim 1, the first three-dimensional structure comprises a first plurality of loops, and angles between adjacent loops of the first plurality of loops increase or decrease along a length of a first segment forming the first three-dimensional structure; and / or An embolic device, characterized in that the second three-dimensional structure includes a second plurality of loops, and the angle between adjacent loops of the second plurality of loops increases or decreases along the length of the second segment forming the second three-dimensional structure.

9. 2. The embolic device of claim 1, An embolic device, characterized in that the first three-dimensional structure has at least two adjacent loops that form a first angle, and the second three-dimensional structure has at least two adjacent loops that form a second angle that is smaller than the first angle.

10. The embolic device according to any one of claims 1 to 9, An embolic device, wherein the first segment and the second segment are portions of an elongate member having a distal end and a proximal end.

11. 1. An embolic device for placement in a body lumen, comprising: an elongate member having a proximal end and a distal end; the elongated member comprising a first segment configured to form a first three-dimensional structure, the first three-dimensional structure defining a cavity; An embolic device, wherein the elongated member includes a second segment configured to form a second three-dimensional structure within a cavity of the first three-dimensional structure.

12. 12. The embolic device of claim 11, An embolic device, characterized in that a first three-dimensional structure formed by a first segment of the elongated member includes a first loop, and a second three-dimensional structure formed by a second segment of the elongated member includes a second loop.

13. 13. The embolic device of claim 12, An embolic device, wherein a first curvature of a first loop of the first three-dimensional structure is less than a second curvature of a second loop of the second three-dimensional structure.

14. The embolic device according to any one of claims 11 to 13, the first segment has a first width and the second segment has a second width that is smaller than the first width; and / or An embolic device, wherein the first segment has a first thickness and the second segment has a second thickness that is less than the first thickness.

15. The embolic device according to any one of claims 11 to 13, An embolic device, wherein the first segment and the second segment form a unitary construction.

16. The embolic device according to any one of claims 11 to 15, An embolic device, wherein each of the first segment and the second segment comprises a braided segment.

17. 12. The embolic device of claim 11, the first three-dimensional structure comprises a first plurality of loops, wherein a loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof, of each loop of the first plurality of loops increases or decreases along a length of a first segment forming the first three-dimensional structure; and / or An embolic device, characterized in that the second three-dimensional structure includes a second plurality of loops, and the loop width, loop curvature, braid width, braid thickness, braid angle, or any combination thereof, of each loop of the second plurality of loops increases or decreases along the length of a second segment forming the second three-dimensional structure.

18. 12. The embolic device of claim 11, the first three-dimensional structure comprises a first plurality of loops, the angles between adjacent loops of the first plurality of loops increasing or decreasing along the length of a first segment forming the first three-dimensional structure; and / or An embolic device, characterized in that the second three-dimensional structure includes a second plurality of loops, and the angle between adjacent loops of the second plurality of loops increases or decreases along the length of the second segment forming the second three-dimensional structure.

19. 12. The embolic device of claim 11, An embolic device, characterized in that the first three-dimensional structure has at least two adjacent loops that form a first angle, and the second three-dimensional structure has at least two adjacent loops that form a second angle that is smaller than the first angle.

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