Inflatable medical balloons with continuous fiber wind
11351338 · 2022-06-07
Assignee
Inventors
- Alexander Quillin Tilson (Burlingame, CA)
- Jonathan Kurniawan (Belmont, CA, US)
- Mark Christopher Scheeff (Oakland, CA, US)
Cpc classification
A61M2025/1084
HUMAN NECESSITIES
A61M25/005
HUMAN NECESSITIES
International classification
Abstract
A fiber-reinforced medical balloon includes a cylindrical central portion. The balloon includes first and second conical portions connected to the cylindrical central portion along a central longitudinal axis extending from a first end of the balloon to a second end of the balloon. The balloon includes a plurality of first fiber strands extending from the first end of the balloon to the second end of the balloon. Each strand of the plurality of first fiber strands runs substantially parallel to the longitudinal axis through the cylindrical central portion and radially around at least a portion of the first and second conical portions. The balloon includes at least one second fiber strand extending radially around the central portion. The strands are applied as part of a single continuous fiber.
Claims
1. A medical apparatus comprising: a balloon including a central portion and first and second tapered portions connected to the central portion, the balloon including a longitudinal axis extending from a first end of the balloon to a second end of the balloon; and a single continuous fiber including a first portion extending along the central portion the balloon, a second portion extending circumferentially around the central portion of the balloon, circumferentially around the first or second tapered portions of the balloon, or circumferentially around both the first or second tapered portions and the central portion of the balloon and a third portion extending substantially parallel to the longitudinal axis along the central portion of the balloon.
2. The medical apparatus of claim 1, wherein the first and third portions extend underneath the second portion of the single continuous fiber.
3. The medical apparatus of claim 1, wherein the second portion extends helically around the central portion.
4. The medical apparatus of claim 1, wherein one of the first or third portions extends generally perpendicular to the second portion.
5. The medical apparatus of claim 1, wherein a turnaround from the first portion to the second portion is in one of the first and second tapered portions.
6. The medical apparatus of claim 1, wherein a first turnaround from the first portion to the third portion is in the first tapered portion, and a second turnaround from the third portion to a fourth portion of the single continuous fiber is in the second tapered portion.
7. The medical apparatus of claim 1, wherein the first portion and third portion extend substantially parallel to the longitudinal axis.
8. The medical apparatus of claim 1, wherein the second portion wraps around the central portion a plurality of times with a constant pitch.
9. The medical apparatus of claim 1, wherein the second portion wraps around the central portion a plurality of times with a variable pitch.
10. A medical apparatus, comprising: a balloon including a central portion and first and second tapered portions connected to the central portion, the balloon including a longitudinal axis extending from a first end of the balloon to a second end of the balloon; and a single continuous fiber including a first portion extending along the central portion of the balloon and a second portion extending circumferentially around the central portion of the balloon, circumferentially around the first or second tapered portions, or circumferentially around both the first or second tapered portions and the central portion of the balloon.
11. The medical apparatus of claim 10, wherein the single continuous fiber includes a third portion extending along the central portion of the balloon.
12. The medical apparatus of claim 11, wherein the first and third portions are generally parallel to the longitudinal axis and the second portion is generally perpendicular to the longitudinal axis.
13. The medical apparatus of claim 11, wherein a turnaround from the first portion to the third portion is in one of the first and second tapered portion.
14. The medical apparatus of claim 10, wherein a first turnaround from the first portion to the third portion is in the first tapered portion, and a second turnaround from the third portion to a fourth portion of the single continuous fiber is in the second tapered portion.
15. A medical apparatus, comprising: a balloon including a central portion and first and second tapered portions connected to the central portion, the balloon including a longitudinal axis extending from a first end of the balloon to a second end of the balloon: and a fiber forming a longitudinal wind and a hoop wind en extending circumferentially around the central portion of the balloon, circumferentially around the first or second tapered portions, or circumferentially around both the first or second tapered portions and the central portion of the balloon.
16. The medical apparatus of claim 15, wherein the longitudinal wind extends repeatedly along the first and second tapered portions and the central portion of the balloon.
17. The medical apparatus of claim 15, wherein each longitudinal wind includes a turnaround on the balloon.
18. The medical apparatus of claim 15, wherein the hoop wind extends helically around the balloon.
19. The medical apparatus of claim 15, wherein the hoop wind extends helically around the first and second tapered portions and the central portion of the balloon.
20. The medical apparatus of claim 15, wherein the hoop wind extends over the longitudinal wind.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The novel features of the invention are set forth with particularity in the claims that follow. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
(21)
(22)
(23)
(24)
(25)
DETAILED DESCRIPTION
(26) In general, described herein is a fiber-reinforced device, such as a medical balloon, that is formed by the application of a continuous fiber wind. The balloon includes fiber or fiber strands extending substantially parallel to the longitudinal axis within the central portion and radially around the end portions of the balloon.
(27) Referring to
(28) The conical portions 1303a,b extending between the central portion 1301 and the end portions 1305a,b can have a cross-section of decreasing radius extending from the central portion 1301 to the end portions 1305a,b, i.e., can be in the shape of a cone. In some embodiments, the conical portions 1303a,b can have areas of extension or distension, such as have a bulbous or rounded section therein. Further, the conical portions 1303a,b can each have subsections 1307a,b and 1309a,b. Subsections 1307a, b can extend from the central portion 1301 and can have a substantially convex outer surface while the subsections 1309a,b can extend from the end portions 1305a,b and can have a substantially concave outer surface. The respective convex and concave outer surfaces can advantageously provide for a smooth outer surface of the balloon, even at locations of quickly changing diameter.
(29) As is further shown in
(30) Referring still to
(31) Referring to
(32) Referring to
(33) Referring to
(34) Referring to
(35) Referring to
(36) It should be understood that while only 12 strands 1313 have been shown around the circumference of the central portion 1301 for clarity purposes, the pitch of the strands 1313 can be much higher. For example, the pitch of the strands 1313 can be between 8 and 100 pitch, more narrowly, 30 and 50 pitch, such as approximately 40 pitch. Further, although the fiber strands were described as being laid down consecutively, they need not be. For example, the strands 1313 might be laid down in separate groups.
(37) In some embodiments, the hoop strand 1315 can be applied using the same continuous fiber 85. In one embodiment (shown in
(38) Referring to
(39) Alternate configurations are possible. For example, as shown in
(40) Referring to
(41) Referring to
(42) In some embodiments, rather than having each longitudinal strand extend the entire length of the inflatable device, the longitudinal strands can reverse or turn around in the conical portions. For example, some of the longitudinal strands can reverse at the point where the rest of the longitudinal fibers go from being substantially parallel to the longitudinal axis to winding radially around. Advantageously, by having such strands that reverse within the cone rather than extending all the way to the end of the balloon, there can be less build-up of fiber in the ends of the cone.
(43) In some embodiments, the longitudinal fiber strands 1313 can extend substantially parallel to the longitudinal axis 108 within the end portions 1305a,b. Thus, each strand can extend substantially parallel to the longitudinal axis 108 within the central portion 1301, radially around at least part of the conical portions 1303a,b, and substantially parallel to the longitudinal axis 108 within the end portions 1305a,b.
(44) The sacrificial shafts 2000a,b can be removed after all of the fiber has been applied. In some embodiments, a portion of the inflatable device and/or shaft over which fiber has been applied can be cut off. Doing so can advantageously remove unnecessary thickness at the turnarounds. Thus, during application, the turnaround point for some or all of the strands 1313 (i.e. the connection from one strand to the next strand) can be laid down either over the sacrificial shafts 2000a,b or over the inflatable device 2 itself. In
(45) The fiber strands described herein can be part of a fiber matrix, such as fibers extending within a resin, adhesive, or thermally weldable material (such as a TPU). The resin, adhesive, or thermally weldable material may be applied to the fibers before, during, or after the fibers are placed on the inflatable device 2.
(46) The inflatable device 2 described herein can include additional radial sections aside from those described herein. For example, referring to
(47) To manufacture the entire balloon wall 1331, a bladder can first be created. For example, referring to
(48)
(49)
(50)
(51)
(52)
(53) Referring to
(54) The spool 244 can be passively (e.g., freely) or actively rotated, deploying fiber 85. Before or during winding, the fiber 85 may be infused or coated with an adhesive, a solvent, or both. A tool arm 246 can be attached to a rotating tool wheel 248. The tool arm 246 can rotate and translate to position the tool wheel 248 normal to and in contact with the inflatable device 2. The tool wheel 248 can apply pressure normal to the surface of the inflatable device 2 so as to help attach the fiber 85 to the surface upon which it is being applied and/or spread monofilaments of the fiber tow across the device. The tool wheel 248 may help to adhere the fiber 85 to the inflatable device 2, for example by applying pressure and following closely the surface of the inflatable device 2 or mandrel 230. The tool wheel 248 can be heated to soften or melt the material on the surface of the balloon 20. Another heat source or a solvent may be used to tack the fiber in place, to melt or solvate a material on the balloon, to melt or solvate a material on the fiber or combinations thereof. A separate resistive heater, a laser, a UV light source, an infrared light source, a source of hot air, or an RF welder may be used with or without the tool wheel 248 to attach the fiber. A solvent such as methyl ethyl ketone or tetrahydrofuran or alcohol or combinations thereof may promote adhesion of the fiber 85 and may be used with our without the tool wheel 248. The tool wheel 248 can be made of or coated with a non-stick material. The tool wheel 248 may not rotate. The tool wheel 248 may comprise a hard surface, for example carbide. In some embodiments, a nozzle having a hard surface can be used in place of the tool wheel 248.
(55) In some embodiments, an adhesive or thermally weldable material, such as thermoplastic polyurethane (TPU), can be applied to the bladder to help stick the fiber thereto. Further, in some embodiments, the fiber can be dipped through a solvated adhesive or thermally weldable material, such as TPU, during the application. In some embodiments, the material can be applied by spraying. In cases where both solvated thermally weldable material and thermally weldable material on the bladder are used, the native thermally weldable material can advantageously meet the solvated thermally weldable material to help aid the adhesive properties. Adhesive or thermally weldable material can be applied during application of fiber or after the wind is concluded.
(56) Further, in some embodiments, an outer layer can be applied over the fiber wind. The outer layer can be formed, for example, of a panel or panels of film wrapped around the fiber-covered device, similar to described and shown with respect to
(57) In some embodiments, the inner or outer layers described herein can be formed by deposition. For example, a metal such as gold (or other materials listed herein) may be deposited to form a layer. The layers may be formed by vapor deposition, such as physical vapor deposition, chemical vapor deposition or combinations thereof. For example, materials such as parylene, polyimide, polynapthalene, Polyphenylene Vinylenes, fluoropolymer blends, Polyazomethine, poly-fluorohydrocarbons, poly-perfluorocarbons, polyolefins, or combinations thereof may be deposited. Vapor deposited layers can advantageously be pinhole free, thereby enhancing the leak-resistance of the inflatable device. Furthermore, vapor deposition allows for the layers to be easily mass-produced.
(58) After all of the layers of the wall 1331 have been applied to the mandrel, the wall 1331 can be consolidated. For example, referring to
(59)
(60) Mold 622 may be placed in an oven and heated. Mold 622 may have built in heaters. The balloon mold may be placed under vacuum or placed in a vacuum chamber during heating. Heating the balloon under pressure may cause one or more layers or sections to melt and/or fuse and/or bond with adjoining layers or sections. The melting under pressure may remove voids or pockets in the balloon wall. The outer inner and outer layers (72b, 72a) may not melt. Heating the balloon under pressure may cause the wall 1331 of the inflatable device 2 before final consolidation to fuse or laminate into one continuous structure. The balloon outer wall 22b and/or outer layer 72a may be substantially smoothed by this process. The balloon outer wall 22b and/or outer layer 72a may be permeable or perforated such that gas or other material trapped in the balloon wall 22 during manufacture may escape when the balloon is heated under pressure.
(61) The fibers described herein can be made from a variety of materials. Exemplary materials include Vectran®, PBO, Spectra®, Conex®, Dyneema®, Technora®, Dacron®, Compet®, Polyester, Nylon, PEEK, PPS, Boron Fiber, Ceramic Fiber, Kevlar®, Inorganic Carbon or Carbon fiber, Inorganic silicon or high strength fiberglass, Organic polymer or aramid, Twaron®, Tungsten, Molybdenum, Stainless Steel, Nickel/cobalt alloys, Titanium alloys, and Nitinol alloys.
(62) The inflatable devices 2 described herein can be used as medical invasive balloons, such as those used for transcutaneous heart valve implantation are disclosed. For example, those balloons used for transcatheter aortic-valve implantation. Inflatable device 2 may also be used for angioplasty in both coronary and peripheral applications.
(63) In one exemplary embodiment, an inflatable medical device for use in BAV can have a diameter of approximately 20 mm, a burst pressure of around 10 atm, 40 tows per inch lengthwise in the central portion (about 126 tows in a one-inch diameter balloon), and 60 tows per inch in the hoop wind in the central portion. The tow can have 8 mono-filaments and a break strength of about 1.4 lbs.
(64) Advantageously, the inflatable device described herein is configured to help prevent helical or circumferential failures. That is, because the fibers extend substantially parallel to the longitudinal axis within the central portion of the device (which has the largest diameter), the device is most likely to fail along those parallel fibers in the central portion. Such failure substantially along the longitudinal axis can advantageously allow for ease of pull-out through a sheath or introducer. Should the central portion be helically wound, hoop fibers can be deposited at or near the shoulder such that the burst failure would be helical, but constrained to an increasingly narrow central zone.
(65) Furthermore, the fiber strands of the inflatable device described herein can be laid down continuously with minimized tooling. The process can be automated and easily updated. The fiber application process can be performed quickly, particularly the application of the strands parallel to the longitudinal axis. Further, since the path of the machine is controlled by a computer running software, the automated process allows for ease of changeability between different size and shapes of inflatable devices. After a device is loaded, the application of all the fiber can be accomplished automatically, with no need for human intervention.
(66) The inflatable device described herein can further be engineered to have fiber deposition that exhibits minimized internal wall shear. Wall shear may lead to “slumping” of fiber, wherein fibers, particularly hoop fibers, travel from larger radius sections to smaller radius sections when the balloon is inflated. Travel of hoop fibers may cause premature failure of the balloon and thus limit the balloon's maximum inflation pressure.
(67) The fiber strands of the inflatable device described herein further allow for a decreased build-up of fibers at the ends of the balloon relative, for example, to a balloon wound with a helix pattern.
(68) The fibers for the inflatable device described herein are further advantageously applied using slight tension throughout the entire application process, thereby helping to ensure that fiber doesn't lift or move during application.
(69) Any elements described herein as singular can be pluralized (i.e., anything described as “one” can be more than one), and plural elements can be used individually. Characteristics disclosed of a single variation of an element, the device, the methods, or combinations thereof can be used or apply for other variations, for example, dimensions, burst pressures, shapes, materials, or combinations thereof. Any species element of a genus element can have the characteristics or elements of any other species element of that genus. The above-described configurations, elements or complete assemblies and methods and their elements for carrying out the invention, and variations of aspects of the invention can be combined and modified with each other in any combination.