Medical balloons are widely used in medical procedures. Typically, an uninflated medical balloon is inserted into a body space. When the medical balloon is inflated, the volume of the medical balloon expands, and the body space is similarly expanded.
In procedures such as angioplasty, the medical balloon may be used to open a collapsed or blocked artery. A typical medical balloon includes a central barrel portion between tapered or conical portions. The medical balloon may be provided in a non-compliant form by including one or more fiber layers, but compliant and semi-compliant forms are also known in the art.
To provide an outer layer for a medical balloon, past proposals have been made for cutting the ends of a tubular film longitudinally to form radially divided segments that may overlap to surround the tapered end more precisely when attached thereto. However, this leads to the creation of a number of longitudinal seams, which may be undesirable for some applications. Furthermore, if not done with great care, the results from forming the seams can be inconsistent, can lead to longitudinally extending fins. The manufacturing process involving the cutting of an outer layer preform can be complicated and costly, typically requiring an entirely manual process.
Accordingly, a need is identified for a medical balloon that overcomes any or all of the foregoing limitations and possibly others that have yet to be identified.
An object of the disclosure is to provide a composite medical balloon including a hybrid layer including a tube for covering a barrel portion and a spiral wrapping for covering one or both of the tapered or cone portions.
According to a first aspect of the disclosure, a composite medical balloon comprises a base balloon layer including first and second tapered portions with a barrel portion there-between. A hybrid layer includes a tube for covering the barrel portion and a spiral wrapping for covering at least one of the first and second tapered portions.
In one embodiment, the tube comprises an extruded or blow-molded material, which is substantially equal in length to the barrel portion of the base balloon layer. The tube may comprise a polyamide, and the base balloon layer may also comprise a polyamide. The spiral wrapping may comprise a spirally wound ribbon of material extending from a proximal end of the at least one tapered portion to a distal end of the at least one tapered portion. The spiral wrapping may overlap with the tube at a transition from the at least one tapered portion to the barrel portion. The spiral wrapping may comprise a polyether block amide, such as PEBAX, and may cover both tapered portions of the base balloon layer. The balloon may further include a fiber layer over the base balloon layer.
According to a further aspect of the disclosure, a composite medical balloon is provided. The composite medical balloon comprises balloon including first and second tapered portions having a barrel portion therebetween. A hybrid layer is adhesively attached to the balloon. The hybrid layer comprises a tube for covering the barrel portion, a first spirally wrapped ribbon of material for covering the first tapered portion, and a second spirally wrapped ribbon of material for covering the second tapered portion.
In one embodiment, the first spirally wrapped ribbon of material includes a plurality of overlapping winds, including one wind overlapping an edge of the tube that is adhesively bonded at the overlap. The tube and the balloon may each comprise the same material, such as a poly-amide (Nylon). The first and second spirally wrapped ribbons of material comprise a polyether block amide (PEBAX). The tube may be substantially equal in length to a length of the barrel portion of the base balloon layer. The balloon may also include a fiber layer.
A further aspect of the disclosure pertains to a method of forming a composite medical balloon. The method comprises providing a balloon having a barrel portion between first and second tapered portions. The method further comprises forming a hybrid layer on the balloon by applying a tube over the barrel portion of the balloon, and applying a spiral wrapping along one or both of the first and second tapered portions.
In one embodiment, the method includes a step of providing an adhesive to the balloon prior to the forming step. The method may further include the step of inflating the balloon prior to the step of providing an adhesive, deflating the balloon prior to the step of applying the tube, and re-inflating the balloon prior to the step of applying the spiral wrapping. The step of applying the spiral wrapping may comprise applying a spirally wrapped ribbon of material to each of the first and second tapered portions of the balloon. The method may further include the step of laminating the balloon, the tube, and the spiral wrapping.
The above and further advantages of the disclosure may be better understood by referring to the following description in conjunction with the accompanying drawings in which:
The dimensions of some of the elements may be exaggerated relative to other elements for clarity or several physical components may be included in one functional block or element. Further, sometimes reference numerals may be repeated among the drawings to indicate corresponding or analogous elements. Moreover, some of the items depicted in the drawings may be combined into a single function.
In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the present invention. The disclosed embodiments may be practiced without these specific details. In other instances, well-known methods, procedures, components, or structures may not have been described in detail so as not to obscure the present invention.
The principles and operation of systems and methods of the disclosure may be better understood with reference to the drawings and accompanying descriptions. The invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
Certain features of the invention that are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.
With reference to
The diameter 116 of an inflated fiber-reinforced medical balloon 10 in accordance with the one embodiment may be about ten millimeters, but may vary depending on the application. The length of an inflated fiber-reinforced medical balloon 10 in accordance with one embodiment may be about eight centimeters. A balloon 10 with a length 118 of 2-200 centimeters or more is possible. The inclination angle of a tapered or cone portion 108 of an inflated fiber-reinforced medical balloon 10 in accordance with the disclosed embodiment may be about twenty degrees. It will be recognized by those having skill in the art that the fiber-reinforced balloon 10 could be made in a wide variety of diameters 116 and lengths and with a variety of inclinations at the tapered or cone portion 108 of the balloon 10, without limitation.
The fiber-reinforced medical balloon 10 may include a base layer 100 formed of a thin polymer material and a first layer 12 of thin inelastic fibers 13. The balloon 10 may include a second layer 14 made up of one or more fibers 15. An outer layer 16 over the fiber layer(s) 12, 14 may be included, as outlined in the following description.
Each fiber 13 is typically fixed relative to other fibers in the first fiber layer 12 and other fibers in the balloon 10. The thin inelastic fibers 13 of the first fiber layer 12 may be characterized by a high tensile strength, which provide superior burst strength. The fiber-reinforced balloon 10 may also resist abrasion, cuts, and punctures. It may be recognized that enhanced structural integrity may result from the fiber reinforcement.
With further reference to
The base layer 100 is typically formed of a thin film polymeric material, or other suitable materials with high strength relative to film thickness. Polymers and copolymers that can be used for the base layer 100 include the conventional polymers and copolymers used in medical balloon construction, such as, but not limited to, polyethylene, (PET), polycaprolactam, polyesters, polyethers, polyamides, polyurethanes, polyimides, ABS, nylons, copolymers, polyester/polyether block copolymers, ionomer resins, liquid crystal polymers, and rigid rod polymers. The base layer 100 may typically be formed as a blow-molded balloon of a polymer material, such as for example a polyamide, such as nylon.
The base layer 100 may comprise a polymer, which has been cured into the shape of a balloon, may be formed. This base layer 100 of a cured polymer may form the inner polymeric wall of the fiber reinforced balloon. With reference to
A removable balloon similar to base layer 100 may be used as the mandrel 122. The mandrel 122 may be made from a variety of materials. The mandrel 122 may be made in the shape of the interior wall of the desired finished balloon. The mandrel 122 may be made of collapsible metal or polymeric bladder, foams, waxes, low-melting metal alloys, and the like. Once the composite balloon is developed and laminated, the mandrel 122 (i.e., base layer 100) may be removed by melting, dissolving, fracturing, compressing, pressurizing, or other suitable removal techniques.
With reference to
One or more fibers 13 are applied to the base layer 100 to form a first fiber layer 12, as shown in
In a disclosed embodiment, the fibers 13 of the first fiber layer 12 are ribbon-shaped, where the width of the fiber is larger than the thickness of the fiber. The fibers 13 may be flat so that the fiber has a rectangular cross-section. The fibers 13 used in the initial layer of fibers 12 may all be fibers 13 made of the same material and the same shape. Fibers 13 made from different materials may be used in the initial fiber layer 12. Fibers 13 made in different shapes may be used in the initial fiber layer 12. Ultrahigh Molecular Weight (UHMW) Polyethylene fiber 13, which has been flattened on a roll mill may be used to form the first fiber layer 12. To the flattened fiber 13 is applied an adhesive, such as the 1-MP adhesive. The fibers 13 may be arranged as 30 longitudinal fibers, each substantially equal in length to the length of the balloon 10.
The fibers 13 of the initial fiber layer 12 may be arranged so that each fiber 13 is substantially parallel to the long axis of the balloon 10. The density of the fibers 13 in the initial fiber layer 12 is determined by the number of fibers 13 or fiber winds per inch and the thickness of the fibers 13. In a disclosed embodiment of the first fiber layer 12 having longitudinally-placed fibers 13, a fiber density of generally about 15 to 30 fibers 13 having a fiber thickness of about 0.0005 to 0.001 inch and placed equidistant from one another provide adequate strength for a standard-sized fiber-reinforced medical balloon 10. Each of the fibers 13 is substantially equal in length to the balloon 10. The first fiber layer 12 may prevent longitudinal extension of the completed fiber-reinforced balloon 10.
In accordance with a disclosed embodiment, a second fiber layer 14 made with one or more high-strength inelastic fibers 15 is positioned along circumference of the balloon 10, as shown in
The fibers 15 of the second fiber layer 14 may be inelastic fiber, typically made of an inelastic fibrous material. An inelastic fiber is a member of a group of fibers that have very minimal elasticity or stretch in a given range of pressures. Some fibrous materials are generally classified as inelastic although the all fibrous material may have a detectable, but minimal elasticity or stretch at a given pressure. The fibers 15 of the second fiber layer 14 may be high-strength fibers, typically made of a high-strength fibrous material. Some high strength inelastic fibrous materials may include Kevlar, Vectran, Spectra, Dacron, Dyneema, Terlon (PBT), Zylon (PBO), Polyimide (PIM), other ultra-high molecular weight polyethylene, aramids, and the like.
In a disclosed embodiment, the fibers 15 of the second fiber layer 14 are ribbon-shaped, where the width of the fiber is larger than the thickness of the fiber. The fibers 15 may be flat so that the fiber has a rectangular cross-section. The fibers 15 used in the second layer of fibers 14 may all be fibers 15 made of the same material and the same shape. Fibers 15 made from different materials may be used in the second fiber layer 14. Fibers 15 made in different shapes may be used in the second fiber layer 14. UHMW polyethylene fiber 15, which has been flattened on a roll mill may be used to form the second fiber layer 14. To the flattened fiber 15 is applied a thin coat of an adhesive, such as the 1-MP adhesive. The fibers 15 may be arranged as a second fiber layer 14 may have a fiber density of 54 wraps per inch.
The fibers 15 of the second fiber layer 14 may be perpendicular to or substantially perpendicular to the fibers 13 placed longitudinally to form the first fiber layer 12. This transverse placement of the first fiber layer 12 and the second fiber layer 14 allows for maximum radial stability of the fiber-reinforced balloon 10. The placement of the fiber layers 12 and 14 distributes the force on the balloon surface equally, creating pixelized pressure points of generally equal shape, size, and density.
The fibers 13 of the first fiber layer 12 may be the same as or different from the fiber 15 of the second fiber layer 14. Specifically, the fibers 15 of the second fiber layer 14 may be made of a different material or materials than the fibers 13 of the first layer 12. The fibers 15 of the second layer 14 may be shaped differently from the fibers 13 of the first fiber layer 12. The characteristics of the fibers or combination of fibers used for the first or second fiber layers may be determined from the specific properties required from the resulting fiber-reinforced balloon 10.
With respect to the fiber density of the second fiber layer 14, in accordance with the disclosed embodiment, fiber 15 having a thickness of about 0.0005 to 0.001 inch and arranged in parallel lines with about 50 to 80 wraps per inch provides generally adequate strength. A single fiber 15 may form the second fiber layer 14, with the fiber 15 wound in a generally parallel series of circumferential continuous loops.
With reference to
With reference to
With reference to
In accordance with another embodiment, the fibers 47 of the first fiber layer 46 may be positioned parallel to a line at a thirty-degree angle to a line parallel to the longitudinal axis of the balloon 10. In accordance with another embodiment, the fibers 47 of the first fiber layer 46 may be positioned parallel to a line at a forty-five-degree angle to a line parallel to the longitudinal axis of the balloon 10. It will be apparent to those having skill in the art that the fibers 47 may be placed at any appropriate angle.
The fibers 49 of the second fiber layer 48 lie parallel to the circumference of the balloon 10. With reference to
The fiber 44 of the second fiber layer 43 may be positioned parallel to a line at a twenty-degree angle to a line parallel to the circumference of the balloon 10. In accordance with one embodiment, the fiber 44 of the second fiber layer 43 may be positioned parallel to a line at a thirty-degree angle to a line parallel to the circumference of the balloon 10. In accordance with one embodiment, the fiber 44 of the second fiber layer 43 may be positioned parallel to a line at a forty-five-degree angle to a line parallel to the circumference of the balloon 10. It will be apparent to those skilled in the art that the fibers 44 may be placed at any appropriate angle.
The fibers 42 of the first fiber layer 41 and the fibers 44 of the second fiber layer 43 are positioned perpendicularly relative to each other. With reference to
Referring to
Turning to
A tube 70 is then positioned over the adhesive coating applied to the base layer 100 and any overlying fiber layers 12, 14. The tube 70 may correspond in length 118 to the barrel portion 106 and having an inner diameter 116 may be equal to or greater than the outer diameter of the balloon 10, or may be smaller in diameter and stretched by the base layer 100 on inflation The tube 70 may be fabricated of the same material as the base layer 100 (e.g., a nylon or PET film), and may be formed by extrusion or blow-molding. The tube 70 could also be formed by blow-molding a balloon-shaped structure similar to base layer 100 and cutting off the cone portions 104, 108, which results in a tube in a shape and size similar to barrel portion 106.
The balloon 10 with the adhesive coating and the tube 70 in place over the barrel portion 106 is then inflated. This may be achieved by supplying a pressurized fluid (air) from a source 160 through one neck portion 110 and providing a seal 204 at the open end of the other neck portion 102. With the balloon 10 inflated, a different material is applied to at least one of the cone portions 104, 108 in the same layer as the tube 70 in the barrel portion 106. Specifically, a ribbon of material 80, such as one comprising a polymer film, such as for example pre-stretched PEBAX film. The material 80 may have a thickness similar to that of the tube 70, and may be spirally wrapped or wound around one or both of the cone portions 104, 108, so as to form a spiral wrapping. The width of the material 80 may be relatively narrow, such that two or more passes or winds are required to cover the entirety of each cone portions 104, 108, but the arrangement will ultimately depend on the relative dimensions of the material 80 and the cone portions 104, 108. Adhesive may also be applied to the material 80 during spiral wrapping, but may alternatively or additionally be applied directly to the cone portions 104, 108.
The winding of the material 80 may be done in an overlapping manner. Specifically, each wind or pass of the ribbon of material 80 may at least partially overlap with an adjacent wind (as indicated by phantom lines O indicating overlap). Furthermore, the ribbon of material 80 may overlap with the edges of the tube 70 at the transitions 112, 114 adjacent to the cone portions 104, 108, as can be understood by the cross-sectional view of
With the tube 70 any spiral wrapping of material 80 in place, the balloon 10 may then be subjected to lamination or consolidation, such as by placing it within a split die 300, as shown in
Advantageously, this creates a balloon 10 having a hybrid outer layer 16 with several distinct advantages. Specifically, the ability to provide a continuous or seamless tube 70 for the barrel portion 106 allows for the selection of a material with superior properties (e.g. porosity, texture, hardless, etc.) in terms of any associated treatment, such as delivery of a treatment agent or drug (e.g., paclitaxel) coated on the barrel portion, or stent retention/release. The use of a different material for covering the cone portions 104, 108 allows for these regions of the composite balloon 10 to be provided with different properties, such as enhanced flexibility or a differential thickness. Using a spiral wrapping further avoids the need for crimping or folding material around the cone portions 104, 108, which can result in bunching of material when the balloon is laminated and/or folded. This bunched material can also unfurl upon balloon expansion during manufacturing and cause process issues, avoided by using spiral wrapping.
Turning to
As illustrated in
While the embodiments above and shown and described as a balloon having a fiber layer, it should be understood that this is considered an optional feature. Thus, the balloon 10 could simply comprise the base layer 100 and the hybrid outer layer, as proposed, without the inclusion of fibers. Furthermore, any type of intermediate layer may be provided between the base balloon layer 100 and the hybrid outer later to provide the resulting balloon with desired characteristics, such as a particular degree of compliance or an enhanced resistance to bursting.
Summarizing, this disclosure may be considered to relate to the following items:
1. A composite medical balloon, comprising:
As used herein, the following terms have the following meanings:
“A”, “an”, and “the” as used herein refers to both singular and plural referents unless the context clearly dictates otherwise. By way of example, “a compartment” refers to one or more than one compartment.
“About,” “substantially,” or “approximately,” as used herein referring to a measurable value, such as a parameter, an amount, a temporal duration, and the like, is meant to encompass variations of +/−20% or less, including +/−10% or less, +/−5% or less, +/−1% or less, and +/−0.1% or less of and from the specified value, in so far such variations are appropriate to perform in the disclosed invention. However, it is to be understood that the value to which the modifier “about” refers is itself also specifically disclosed.
“Comprise”, “comprising”, and “comprises” and “comprised of” as used herein are synonymous with “include”, “including”, “includes” or “contain”, “containing”, “contains” and are inclusive or open-ended terms that specifies the presence of what follows e.g. component and do not exclude or preclude the presence of additional, non-recited components, features, element, members, steps, known in the art or disclosed therein.
Although the invention has been described in conjunction with specific embodiments, many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it embraces all such alternatives, modifications, and variations that fall within the appended claims' spirit and scope. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present disclosure.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/US2020/045433 | 8/7/2020 | WO |