Ocular drainage system devices and methods

Abstract

To provide ocular drainage systems, where the ocular drainage systems in various embodiments include a compliant fluid conduit configured to be implanted within biological tissue such as tissue of an eye, where the compliant fluid conduit includes an exterior with a microstructure configured to permit cellular ingrowth, where a first end of the compliant fluid conduit is configured to be inserted into an eye of a patient to allow ocular fluid to be drained from the eye, and a second end of the compliant fluid conduit is configured to be inserted into an ocular venous system of the patient to allow the ocular fluid drained from the eye to flow directly into the ocular venous system.SOLUTION: The invention provides favorable ocular drainage systems and the like.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the benefit of Provisional Application No. 62 / 724,180, filed Aug. 29, 2018, and is hereby incorporated by reference in its entirety for all purposes.

Background Art

[0002] Background Aqueous humor fills the anterior chamber of the eye and is a fluid that contributes to the intraocular pressure or the fluid pressure within the eye. Glaucoma is a progressive eye disease characterized by an increase in intraocular pressure. This increase in intraocular pressure is generally caused by insufficient amounts of aqueous humor being reabsorbed by the body. In some cases, the aqueous humor is not absorbed quickly enough or not at all, while in other cases, additionally or alternatively, the aqueous humor is produced too quickly. The increase in intraocular pressure is associated with a gradual, and sometimes permanent, loss of vision in the affected eye.

[0003] To treat glaucoma, many attempts have been made, including surgical procedures that implant devices that operate to drain a portion of the aqueous humor from the anterior chamber and disperse it into the eye tissue for reabsorption. However, implant procedures for conventional glaucoma drainage system devices are associated with many complications, including a progressive decrease in the absorption of aqueous humor through the surrounding tissue due to erosion and scar tissue formation.

[0004] Additional complications arise from the design of conventional devices, which typically lack the flexibility, adaptability, and device / tissue adhesion necessary to avoid micro-movement between the device and surrounding tissue. This micro-movement is known to sometimes cause micro-irritation of the surrounding tissue, leading to a foreign body tissue response and excessive scarring, and thus reducing the absorption capacity of the surrounding tissue. In some cases, persistent micro-irritation of the surrounding tissue can lead to eventual erosion of the device and site infection, which has been associated with the progressive and sometimes permanent loss of vision in the affected eye. In cases where erosion does not occur, scar tissue effectively prevents the reabsorption of aqueous humor drained from the anterior chamber by these conventional devices. These and other complications can act to negate the beneficial treatment provided by conventional devices. The resulting effect is a progressive increase in intraocular pressure and glaucoma. [Overview of the project]

[0005] Abstract According to one example ("Example 1"), the medical device comprises an adaptable fluid conduit configured to be implanted within biological tissue (e.g., within or between tissues of the eye), the adaptable fluid conduit having a first end, a second end, a lumen and an exterior having a microstructure configured to allow internal growth of cells into it, wherein the first end is configured to be inserted into the patient's eye (e.g., the chamber or near the chamber) to allow ocular fluid (e.g., aqueous humor) to drain from the eye, and the second end is configured to be inserted into the patient's ocular venous system to allow the ocular fluid drained from the eye to flow directly into the ocular venous system.

[0006] In another example ("Example 2"), in addition to the features of Example 1, the surface of the lumen wall of the lumen is configured to resist the internal growth and adhesion of cells.

[0007] In another example ("Example 3"), in addition to Example 2, the surface of the lumen wall of the lumen includes a plurality of pores of a size that resists the internal growth and adhesion of cells.

[0008] In another example ("Example 4"), in addition to Example 2, the surface of the lumen wall of the lumen includes a microstructure configured to resist the internal growth and adhesion of cells.

[0009] In another example ("Example 5"), in addition to any of the above examples, the adaptive fluid conduit is a polymer tube.

[0010] In another example ("Example 6"), in addition to Example 5, the polymer tube includes multiple layers.

[0011] In another example ("Example 7"), in addition to Example 6, the plurality of layers include a first layer having a first microstructure and a second layer having a second microstructure.

[0012] In another example ("Example 8"), in addition to Example 5, the polymer tube includes a fluoropolymer.

[0013] In another example ("Example 9"), in addition to Example 8, the polymer tube includes stretched polytetrafluoroethylene.

[0014] In another example ("Example 10"), in addition to any of the examples above, the medical device, when implanted, operates to regulate the intraocular pressure of the patient's eye.

[0015] In another example ("Example 11"), in addition to any of the above examples, the adaptive fluid conduit is configured to allow fluid to flow out of the anterior chamber of the patient's eye when implanted.

[0016] In another example ("Example 12"), in addition to any of the above examples, the adaptive fluid conduit includes one or more individual tubular elements of a plurality of lumens formed in a tubular structure, each tubular element including a lumen extending through it.

[0017] In another example ("Example 13"), in addition to any of the above examples, the medical device further includes a valve configured to regulate the velocity of the fluid flowing through the adaptive fluid conduit.

[0018] In another example ("Example 14"), in addition to Example 13, the valve is formed from a partially unbonded helical winding of the material forming the adaptive fluid conduit, wherein the valve is configured to regulate the reverse flow velocity of the fluid passing through the adaptive fluid conduit in the direction toward the anterior chamber of the eye.

[0019] In another example ("Example 15"), in addition to Example 14, the valve is integrated with the adaptive fluid conduit such that the valve and the adaptive fluid conduit form a monolithic unit.

[0020] According to another example ("Example 16"), in addition to any of the examples described above, the exterior of the adaptive fluid conduit includes a number of pores of a size that allows for the internal growth of cells.

[0021] In another example ("Example 17"), in addition to Example 16, the interior of the adaptive fluid conduit includes a microstructure configured to resist the internal growth and adhesion of cells.

[0022] In another example ("Example 18"), in addition to any of the above examples, the medical device further includes a sheath positioned around the adaptive fluid conduit, the sheath defining the outside of the adaptive fluid conduit.

[0023] In another example ("Example 19"), in addition to any of the above examples, the second end of the adaptive fluid conduit is configured to be inserted into a scleral vein of the eye.

[0024] In another example ("Example 20"), in addition to any of the above examples, the adaptable fluid conduit is made of a non-biobreatable synthetic polymer material.

[0025] According to another example ("Example 21"), a method for treating glaucoma includes providing a compliant fluid conduit having a first end configured to be inserted into a patient's eye (e.g., into or near the anterior chamber) and a second end configured to be inserted into the patient's ophthalmic venous system, wherein the compliant fluid conduit is configured for implantation within living tissue (e.g., within or between eye tissues) and includes an exterior configured to permit ingrowth of cells therein, inserting the first end of the compliant fluid conduit into the patient's eye such that the first end accesses an intraocular fluid reservoir, and inserting the second end of the compliant fluid conduit into the ophthalmic venous system such that fluid within the intraocular fluid reservoir is freely discharged through the compliant fluid conduit into the ophthalmic venous system.

[0026] According to another example ("Example 22"), in addition to Example 21, inserting the first end of the compliant fluid conduit into the patient's eye includes inserting the first end into the anterior chamber of the patient's eye.

[0027] According to another example ("Example 23"), in addition to Example 21, inserting the second end of the compliant fluid conduit into the ophthalmic venous system includes inserting the second end into the suprachoroidal vein of the eye.

[0028] [[ID=##]]According to another example ("Example 24"), in addition to any of Examples 21 - 23, the compliant fluid conduit is a synthetic polymer material that is non - bioabsorbable. [[ID=##]] [[ID=##]]

Brief Description of the Drawings

[0029] [[ID=##]] [[ID=##]]Brief Description of the Drawings[[ID=##]] [[ID=##]]The accompanying drawings are included to provide a further understanding of the embodiments of the invention of the present disclosure, are incorporated herein, form a part thereof, show examples, and together with the description serve to explain the principles of the present disclosure. [[ID=##]] [[ID=##]]

[0030] [[ID=##]] [[ID=##]] [Figure 1] [[ID=##]]FIG. 1 is a schematic view of an eye drainage system extending between anterior chamber access and suprachoroidal vein access of an eye according to some embodiments. [[ID=##]] It should be noted that there seems to be a formatting issue in the original text where the line numbering jumps from 12 to 13 with an incorrect "##" in the middle. I have translated it as best as possible based on the overall context. If you can correct the original text formatting, it will be easier to provide a more accurate translation.

[0031] [Figure 2A] Figure 2A is a schematic diagram of an intraocularly implanted ocular drainage system according to several embodiments.

[0032] [Figure 2B] Figure 2B is a schematic diagram of an intraocularly implanted ocular drainage system according to several embodiments.

[0033] [Figure 3] Figure 3 is a cross-sectional view of an eye showing an implantable ocular drainage system extending between the anterior chamber access and the suprascle vein access of the eye, according to several embodiments.

[0034] [Figure 4] Figure 4 is a schematic diagram of an ocular drainage system including a soft, adaptable tubular element according to several embodiments.

[0035] [Figure 5] Figure 5 is a schematic diagram of a second ocular drainage system, including a soft, flexible tubular element, according to several embodiments.

[0036] [Figure 6A] Figure 6A is a schematic diagram of the normal flow motion through the tubular element of an ophthalmic drainage system according to several embodiments.

[0037] [Figure 6B] Figure 6B is a schematic diagram of abnormal flow motion through a tubular element of an ophthalmic drainage system in several embodiments. [Modes for carrying out the invention]

[0038] Detailed explanation Those skilled in the art will readily understand that various embodiments of the concepts of the invention provided herein can be realized by any number of methods and apparatus configured to perform the intended functions. It should also be noted that the accompanying drawings referenced herein are not necessarily drawn to a fixed scale and may be exaggerated to illustrate various aspects of the disclosure; in this respect, the drawings should not be construed as limiting.

[0039] This disclosure relates to ocular drainage systems, devices, and methods for draining ocular fluid from a patient's ocular chamber filled with ocular fluid so that the ocular fluid can be reabsorbed by the body. Providing a mechanism for reabsorbing ocular fluid drained from the chamber acts to reduce or otherwise stabilize intraocular pressure. In certain embodiments, the ocular drainage system, device, and method provides for draining aqueous humor (ocular fluid) from the anterior chamber of a patient's eye.

[0040] In various embodiments, unlike conventional designs, the ocular drainage system of the present disclosure is constructed from a bioinert, biocompatible, and non-bioresorbable synthetic material configured to allow and / or promote internal tissue growth into one or more regions of the microstructure of the ocular drainage system. Allowing such internal growth helps to minimize micromovement between the ocular drainage system and the surrounding tissue over time. Minimizing micromovement helps to minimize irritation and micro-irritation of the surrounding tissue caused by the interaction between the surrounding tissue and the ocular drainage system, and thus helps to minimize the risk of the ocular drainage system eroding anatomical structures over time. As described below, the ocular drainage system provides a fluid pathway between the ocular chamber (e.g., anterior and / or posterior chamber) and one or more veins in the scleral vascular system.

[0041] An ocular drainage system 1000 is illustrated in relation to an eye 2000 in Figures 1–3. Figure 1 shows the ocular drainage system 1000 extending between an anterior chamber access 2002 and a scleral vein access 2004 of the eye 2000, although the ocular drainage system 1000 may similarly extend between the posterior chamber and the scleral vein of the eye. For simplicity, the anterior chamber will be further described throughout this disclosure, but it is recognized that the posterior chamber or vitreous chamber may similarly be accessed and drained by the ocular drainage system 1000, if desired.

[0042] The anterior chamber (AC, Figure 3) can be accessed by forming an incision, perforation, hole or other access through the sclera 2006 of the eye 2000, such as the limbus of the eye 2000. In some embodiments, one or more suprascle veins 2010 may be accessed by forming an incision, perforation, hole or other access through the sclera 2006 of the eye, adjacent to the suprascle vascular system. Generally, the sclera 2006 is accessed by forming an incision through the conjunctiva 2008. In some embodiments, a pocket may then be formed in the subconjunctival space between the conjunctiva 2008 and the sclera 2006 of the eye 2000. The pocket may be formed to provide space for housing the ocular drainage system 1000 within an anatomical structure (e.g., the eye). As used herein, the term “intra-biological tissue” refers to arrangements within, between, and / or within tissue. In some embodiments, “within biological tissue” refers to the arrangement between two distinct tissues of an organ, such as between the conjunctiva and the sclera of the eye.

[0043] In Figure 1, conjunctival flaps 2012 and 2014 are pulled aside to expose the subconjunctival space between the conjunctiva 2008 and sclera 2006 of eye 2000. In Figure 2A, conjunctival flaps 2012 and 2014 are sutured closed so that the ocular drainage system 1000 extends between the anterior chamber access 2002 and the suprascle vein access 2004 beneath the conjunctiva 2008 of eye 2000. Examples discussed herein include an ocular drainage system 1000 extending between the subconjunctival anterior chamber access 2002 and the subconjunctival suprascle vein access 2004 (for example, the ocular drainage system 1000 is entirely beneath the conjunctiva 2008 and within the subconjunctival space), but the ocular drainage system 1000 may have access to one or more suprascle veins.

[0044] As shown in Figure 2B, in some embodiments, the anterior chamber and the scleral vascular system are accessed via separate incisions, perforations, holes, or other access means. The first incision or other access means occurs near the anterior chamber, and the second incision or access means occurs near the scleral vascular system. In such configurations, a portion of the ocular drainage system 1000 remains outside the eye.

[0045] Figure 3 shows an ocular drainage system 1000 implanted in the eye as shown in Figure 2A, where the ocular drainage system 1000 extends between the anterior chamber access 2002 and the suprascle venous access 2004 beneath the conjunctiva 2008 of the eye 2000.

[0046] In some embodiments, the ocular drainage system 1000 includes a soft, adaptable tubular element 1100. As shown in Figure 4, the tubular element 1100 includes a first end 1104 and a second end 1106 opposite the first end 1104. In some embodiments, a lumen 1102 extends between the first end and the second ends 1104 and 1106. The lumen 1102 may be defined by the inner surface 1108 of the tubular element 1100. The ocular drainage system 1000 may be configured such that the inner surface 1108 of the tubular element 1100 resists, promotes, or tolerates cell invasion and tissue adhesion thereto. In some embodiments, one or more films, membranes, layers, sheaths, or sleeves may define the inner surface 1108 of the tubular element 1100 (and thus the lumen 1102). Similarly, one or more films, membranes, layers, sheaths, or sleeves can be arranged around the outer surface 1110 of the ocular drainage system 1000 to define the outer surface. In some embodiments, one of the first end and the second end 1104 and 1106 is insertable into the anterior chamber of the eye, and the other of the first end and the second end 1104 and 1106 is insertable into or otherwise attached to a blood vessel, such as a suprascle vein. In other embodiments, one of the first end and the second end 1104 and 1106 is insertable into or otherwise attached to the eye (e.g., in or to the sclera) near the anterior chamber of the eye, and the other of the first end and the second end 1104 and 1106 is insertable into or otherwise attached to a blood vessel. In such embodiments, the end that is insertable into or otherwise attached to the eye near the anterior chamber of the eye does not penetrate into the anterior chamber, but rather is configured to receive aqueous humor diffusing from the anterior chamber through the tissues of the eye. Whether inserted directly into the anterior chamber, near the anterior chamber, or otherwise attached, the adaptive fluid conduit is configured to allow fluid to flow out of the anterior chamber of the patient's eye once implanted.

[0047] The ocular drainage system 1000 is configured to promote and / or allow cell invasion and tissue adhesion (also referred to herein as internal growth) to one or more portions of the ocular drainage system 1000. While cell invasion and tissue adhesion are referred to herein as internal growth, it should be understood that the ocular drainage system 1000 is configured to promote and / or allow one or the other or both. Therefore, the term internal growth of tissue should not be limited in all cases to cell invasion or tissue adhesion, or a combination of cell invasion and tissue adhesion. In some embodiments, the entire outer surface 1110 of the tubular element 1100 may be configured to promote or allow cell invasion and tissue adhesion to it. In other embodiments, cell invasion and tissue adhesion may be promoted or allowed at one or more distinct locations along the outer surface 1110 of the tubular element 1100, but resisted at one or more second portions (e.g., one or more other locations) of the outer surface 1110 of the tubular element 1100. In some embodiments, a film, membrane, layer, sheath, and / or sleeve forming part or all of the outer surface 1110 may be configured to promote or allow cell infiltration and tissue adhesion to it, either on the entire outer surface 1110 or at distinguished locations on the outer surface 1110. Such a configuration provides that tissue intrinsic growth is promoted along one or more regions or portions of the ocular drainage system 1000. As described above, tissue intrinsic growth to one or more regions or portions outside the ocular drainage system 1000 can help minimize micromovement between the ocular drainage system 1000 and the surrounding tissue after it has been implanted, and can aid in the biointegration of the ocular drainage system 1000 into the anatomical structure (e.g., the eye).

[0048] The tubular element 1100 can be formed from a variety of biocompatible materials, including, but not limited to, silicone, stretched polytetrafluoroethylene (ePTFE), polycarbonate, polyethylene, polyurethane, polysulfone, polyvinylidene fluoride (PVDF), polyhexafluoropropylene (PHFP), perfluoroalkoxy polymer (PFA), polyolefin, fluorinated ethylene propylene (FEP), acrylic copolymer, and polytetrafluoroethylene (PTFE). The material forming the tubular element 1100 can be elastic or inelastic.

[0049] In some embodiments, the tubular element 1100 may be formed by a tubular melt extrusion process and drawn down to the final target dimensions. In other embodiments, the tubular element 1100 may be formed by a tube paste extrusion and expansion process to produce the desired wall thickness, porosity, rigidity, and / or dimensions. In some other embodiments, the tubular element 1100 may be formed by continuously dipping a material onto a mandrel of appropriate size, followed by a solvent removal and mandrel extraction process.

[0050] In some embodiments, the tubular element 1100 is formed by one or more tape wrapping processes involving one or more tapes of a desired material (e.g., ePTFE). For example, the tape can be wrapped around a mandrel of desired dimensions and cross-section. In some embodiments, the tape is helically wrapped around the mandrel. The tape can be helically wrapped such that adjacent or successive windings overlap each other (completely or partially), do not overlap, or are some combination thereof, to achieve a tubular element having desired properties. The tape can be wrapped or wound around the mandrel one or more times to form one or more overlapping layers. One or more additional windings of one or more different materials, such as similar materials with different microstructures, can then be applied to it to achieve a tubular element having desired properties (e.g., by additional windings such as helical winding, dip coating, or other known methods). In some embodiments, the tape windings and / or layers can be joined together using one or more thermal or adhesive methods, either before or after removal from the mandrel.

[0051] The tubular element 1100 can be formed from multiple layers, and it should be understood that the different layers may have different physical properties, including, but not limited to, different porosity, durometer, thickness, and / or wettability. For example, in some embodiments, the outer winding layer of the tubular element 1100 may be more porous (or contain a more open microstructure) compared to the inner winding layer of the tubular element 1100. As a result of the configuration of the layer windings, the ophthalmic drainage system 1000 may be selectively configured to allow or promote cell invasion and tissue adhesion in one or more parts or regions thereof, while resisting cell invasion and tissue adhesion in one or more other parts or regions thereof.

[0052] For example, one or more portions or regions may include pores defined by gaps, perforations and / or channels formed on the outer surface 1110, which are of a size and / or shape that promotes or allows for internal tissue growth, cell invasion and / or tissue adhesion. Gaps, perforations and / or channels in the tubular element 1100 may occur naturally or be artificially formed. For example, in some embodiments, one or more perforation processes, such as drilling, die punching, needle punching or laser cutting processes, can be additionally or alternatively used to form multiple perforations in one or more portions of the tubular element 1100. In some embodiments, such perforation processes may be performed before and / or after the tubular element 1100 is formed.

[0053] In some embodiments, the tubular element 1100 may include pores having an average size of 20 to 100 microns, for example, 40 to 80 microns. In other embodiments, the average size of the pores may exceed 100 or 150 microns. In some embodiments, the pore size corresponds to the length of the fibrils and the spacing of the nodes in the stretched polytetrafluoroethylene (ePTFE) microstructure. In other embodiments, the pore size may correspond to a woven or knitted pattern (e.g., in a woven or knitted material). In yet another embodiment, the pore size may correspond to the arrangement of fibers (e.g., in an electrospinning structure in which a polymer is dissolved in a solvent and the solution is then delivered to a mandrel to continuously construct layers of fibrous material).

[0054] In some embodiments, one or more portions or regions of the tubular element 1100 (e.g., inner surface 1108) may be non-porous (e.g., aporous) or may include pores defined by gaps, perforations and / or channels formed on the outer surface 1110 of a size and shape that resists internal tissue growth, cell invasion and / or tissue adhesion. In some embodiments, a portion (or all) of the tubular element 1100 contains pores having an average size of less than 1 or 2 microns. Pore sizes of about 1 or 2 microns or less generally inhibit internal growth of blood vessels and other tissues. These regions or portions of the tubular element 1100 configured to resist cell invasion may also be the result of one or more coatings or other surface treatment applications. In some embodiments, these one or more portions or regions may be made inherently non-porous to minimize, inhibit or otherwise resist internal tissue growth.

[0055] Material coating processes can be used to apply one or more drug or antimicrobial coatings (e.g., metal salts (e.g., silver carbonate)) to polymer materials, and organic compounds (e.g., chlorhexidine diacetate) can also be applied to polymer materials. Hydrophilic coatings can also be applied to allow immediate wetting of the polymer matrix of polymer materials when some polymer surfaces are inherently hydrophobic. Surface coatings containing antioxidant components can be applied to reduce the body's inflammatory response that naturally occurs during postoperative wound healing. The surface of polymer materials can be modified with antiproliferative compounds (e.g., mitomycin C and 5-fluoracil) to mitigate tissue reactions around the eyes. In some embodiments, one or more surface preconditioning processes can be additionally or alternatively used to form layers exhibiting specific microstructures (e.g., wrinkles, folds, or other geometric out-of-plane structures), as described in Zaggl's U.S. Patent No. 9,849,629 filed August 21, 2014. Such surface preconditioning can facilitate a bolder initial inflammatory phase after surgery and provide an early, stable interface between the implantable device and the surrounding tissue. In some embodiments, heparin coating can be applied additionally or alternatively to help minimize cell formation, including fibrinogen accumulation, following the implantation procedure of the ocular drainage system 1000.

[0056] The diameter of the lumen 1102 of the tubular element 1100 is large enough to facilitate the flow of aqueous humor (ocular fluid) through the ocular drainage system 1000 while avoiding an outer diameter that significantly interferes with or impairs normal eye function (e.g., not interfering with blinking or normal eye movements). In some embodiments, the outer diameter of the tubular element 1100 can be in the range of 50 to 300 microns, for example, 100 to 200 microns, but various dimensions are possible.

[0057] The diameter of the lumen 1102 (for example, the inner diameter of the tubular element 1100) can be constant or can vary along the length of the tubular element 1100. For example, the tubular element 1100 may have a first diameter at a first end, a second diameter at a second end, and a third diameter at a position along the length of the tubular element 1100 between the first and second ends. In this example, it should be understood that the second diameter can be larger than the first and third diameters, and the third diameter can be larger (or smaller) than the first diameter. Therefore, in some embodiments, the first and second diameters may be larger than the third diameter, or the third diameter may be larger than each of the first and second diameters. When the diameter of the lumen 1102 varies along the length of the tubular element 1100, the diameter may vary continuously or discontinuously (for example, in a stepwise manner). Additionally or alternatively, the wall thickness of the tubular element 1100 may be constant or vary along the length of the tubular element 1100. Therefore, in some embodiments, the diameter of the lumen 1102 may vary along the length of the tubular element 1100, and the wall thickness of the tubular element 1100 may vary along the length of the tubular element 1100, so that the tubular element 1100 maintains a constant outer diameter (e.g., the diameter of the outer surface of the tubular element 1100) along the length of the tubular element 1100. Alternatively, in some embodiments, the diameter of the lumen 1102 may remain constant along the length of the tubular element 1100, and the wall thickness of the tubular element 1100 may vary along the length of the tubular element 1100, so that the tubular element 1100 maintains a constant inner diameter along its length. While examples of tube diameters and thicknesses have been provided, various dimensions are conceivable and are considered to be within the scope of the present invention.

[0058] The length of the tubular element 1100 generally corresponds to the patient's anatomical structure (e.g., 25 millimeters) and can be pre-selected from a kit containing multiple tubular elements of different sizes, for example, or can be formed by modifying a tubular element 1100 having a general length. Thus, in some embodiments, the tubular element 1100 may exceed the actual length of the patient's anatomical structure, in which case the physician can trim the tubular element 1100 to the desired / required length before or during the implant procedure.

[0059] In some embodiments, the tubular element 1100 is adaptable, forming an adaptable fluid conduit. Adaptability is generally considered the reciprocal of stiffness and can be understood as representing the endurance of a material to deform or strain when subjected to stress. Adaptable materials are understood to have a low modulus of elasticity, so that considerable strain can occur with small stresses (also called a low modulus of elasticity). In comparison, stiff materials (or relatively inadaptive materials) do not deform much when subjected to stress (also called exhibiting a high modulus of elasticity). Therefore, in some embodiments, the tubular element 1100 can be adaptable in that it is configured to deform or strain when subjected to relatively small stresses. The deformation can take the form of radial and / or longitudinal adaptability.

[0060] In some embodiments, the adaptability of the tubular element 1100 may be characterized by a lack of structural integrity corresponding to the loss of a significant portion of its cross-sectional area when the tubular element 1100 needs to support itself, without any external forces other than gravity acting on it. Additionally or alternatively, the adaptability of the tubular element 1100 may be characterized by its bending stiffness.

[0061] Therefore, the tubular element 1100 may be understood to generally lack the structural integrity (e.g., hoop strength and / or column strength) necessary to advance within an anatomical structure without some form of temporary structural support to avoid collapse under its own weight and / or to assist during implantation or advancement within the anatomical structure. In some embodiments, support is provided to the tubular element 1100 by a separate support component (e.g., a mandrel extending inside or outside the tubular element 1100), as described below.

[0062] In various embodiments, the tubular element 1100 may be subjected to one or more material conditioning processes to achieve structurally sound first and / or second ends 1104 and 1106, or to enhance the structural integrity of other parts along the length of the tubular element 1100, with more adaptable parts forming the remainder of the tubular element 1100. As an addition or alternative, in some embodiments, the material of the tubular element 1100 may be subjected to one or more material preconditioning processes so that, upon subsequent construction of the tubular element 1100, one or more of the first and second ends 1104 and 1106 are sufficiently structurally sound according to the discussion herein.

[0063] In some embodiments, to avoid the potential risk of restricted entry of aqueous humor from the anterior chamber into the lumen 1102 of the tubular element 1100, the tubular element 1100 may be configured such that one or more of the first end 1104 and the second end 1106 are operable to maintain lumen integrity at the first end and / or the second ends 1104 and 1106, while other portions of the tubular element 1100 extending between them lack a sufficient amount of structural integrity to maintain lumen integrity in those regions. For example, in some embodiments, the tubular element 1100 is configured such that an end of the tubular element 1100 placed in the anterior chamber (AC) (e.g., the first end 1104) maintains lumen integrity and avoids collapse or otherwise significant deformation of the lumen 1102 in a region adjacent to at least that end (e.g., the first end 1104). Since the relatively structurally sound end of the tubular element 1100 (e.g., the first end 1104) floats in the aqueous humor of the anterior chamber (AC) and therefore does not interact with tissue in a way that could cause micro-stimuli, complications related to micromotion and micro-stimuli due to rigidity are generally avoided.

[0064] Additionally or alternatively, one or more structural members, such as stents, struts, and / or reinforcing elements, can be incorporated, integrated, or joined to one or more of the first and second ends 1104 and 1106 to achieve a tubular element 1100 having a first and / or second end 1104 and 1106 that is sufficiently structurally sound. Such stents, struts, and / or reinforcing elements may be formed from any suitable biocompatible material discussed herein (e.g., natural materials, or synthetic materials such as metals and polymers). In some embodiments, one or more of the first and second ends 1104 and 1106 of the tubular element 1100 may be flared. In some embodiments, localized densification of the first and second ends 1104 and 1106 of the tubular element 1100 or other parts of the tubular element 1100 can increase its structural integrity to a degree sufficient to resist closing forces applied by body tissue. In some embodiments, one or more of the first and second ends 1104 and 1106 (or end portions) can be selectively coated or absorbed with a material such that the first end 1104 and / or second end 1106 have increased elasticity or increased hoop strength relative to the portion of the tubular element 1100 located between the first and second ends 1104 and 1106. For example, one or more of the first and second ends 1104 and 1106 of the tubular element 1100 can be selectively absorbed with silicone or another suitable material. Increasing the elastic and / or hoop strength of one or more of the first end and the second ends 1104 and 1106 compared to the portion of the tubular element 1100 located between the first end and the second ends 1104 and 1106 can help increase the structural integrity of the first end 1104 and / or the second end 1106, and can help avoid collapse or breakage of the first end 1104 and / or the second end 1106 due to forces applied to the first end 1104 and / or the second end 1106 by the patient's anatomical structure.

[0065] In some embodiments, if an adaptable tube is undesirable, one or more stents, struts and / or reinforcing elements may be incorporated into, integrated with, or bonded to the tubular element 1100, in addition to or instead of being incorporated into the first and second ends 1104 and 1106. In some embodiments, in addition to or instead of local densification of the first and second ends 1104 and 1106 of the tubular element 1100, densification of the tubular element 1100 may be carried out to increase the structural integrity of the tubular element 1100 to a degree sufficient to resist the closing forces applied by body tissue. In some embodiments, in addition to or instead of selectively coating or absorbing the first end 1104 and / or the second end 1106 with silicone (e.g., silicone rubber), the portion of the tubular element 1100 between the first end 1104 and the second end 1106 can be additionally or alternatively selectively coated or absorbing with a material (e.g., silicone rubber) to increase its elasticity and / or hoop strength.

[0066] In various embodiments, the tubular element 1100 can be porous (micro or macroporous) or nonporous, or may include a combination of porous (micro or macroporous) and nonporous portions. In some embodiments, the tubular element 1100 may have a length defined by a first portion and a second portion. In some embodiments, the first portion may be a nonporous portion, while the second portion may be a porous portion. In some embodiments, the nonporous portion is impermeable to ocular fluid (e.g., aqueous humor) and resistant to internal tissue growth, while the porous portion is permeable to ocular fluid. The porous portion may be configured to resist or allow internal tissue growth while maintaining permeability to ocular fluid. Thus, in some embodiments, ocular fluid drained from the eye chamber by the tubular element 1100 can then penetrate the surrounding tissue at a desired rate through the porous portion of the tubular element 1100. The porosity (micro or macro) of the porous portion of the tubular element 1100 determines the rate at which aqueous humor penetrates through the porous portion. For example, ophthalmic fluid will permeate through the microporous portion at a slower rate than ophthalmic fluid permeates through the macroporous portion.

[0067] In some embodiments, portions of the tubular element 1100 configured to extend within the ocular chamber may have an outer surface that is impermeable to ocular fluid or cell infiltration, while portions of the outer surface of the tubular element 1100 extending outside the ocular chamber (e.g., between the anterior chamber and the blood vessel to which the tubular element 1100 terminates) may be configured to promote or allow the invasion of internal tissue or cell growth and / or be permeable to ocular fluid. In some embodiments, the inner surface of the tubular element 1100 may be impermeable to ocular fluid and configured to minimize internal tissue growth. In some embodiments, the porosity of the tubular element 1100 may vary along the length of the tubular element 1100. Additionally or alternatively, in some embodiments, the porosity of the tubular element 1100 may vary radially through the tubular wall of the tubular element 1100. This may act to control the depth to which internal growth can occur. In some embodiments, one or more of the first end and the second end 1104 and 1106 (or end portions) may be selectively coated or absorbed with a material such that the first end 1104 and / or the second end 1106 have reduced permeability to the portion of the tubular element 1100 between the first end and the second end 1104 and 1106. For example, one or more of the first end and the second end 1104 and 1106 of the tubular element 1100 may be selectively absorbed with silicone or another suitable material.

[0068] The flow of ophthalmic fluid (e.g., aqueous humor) through the ophthalmic drainage system 1000 is generally governed by the pressure difference across the tubular element 1100, and is a function of the pressure difference between the two ends of the tubular element 1100 and the resistance to the flow through the tubular element. In an example where the ophthalmic drainage system 1000 includes a first end 1104 located in the anterior chamber (AC) and a second end 1106 located in a blood vessel, the pressure difference across the tubular element 1100 can therefore be a function of the pressure difference between the intraocular pressure in the anterior chamber and the pressure in the blood vessel, as well as the resistance to the flow of aqueous humor through the lumen 1102 of the tubular element 1100.

[0069] The flow resistance through the tube is a function of the flux resistance of the tubular element (e.g., based on the tube's geometry, diameter, length, and the Hagen-Poiseuille formula). However, as described above, the tubular element 1100 is generally soft, flexible, exhibits low column and hoop strength, and generally cannot support its own weight. That is, in some embodiments, the tubular element 1100 lacks sufficient structural integrity to avoid collapsing under its own weight. Therefore, the flow through the tubular element 1100 depends further on the force required to maintain the expansion (partial or whole) of the lumen 1102 of the tubular element 1100.

[0070] In some embodiments, intraocular pressure in the anterior chamber causes the tubular element 1100 to expand or otherwise act in such a way as to maintain its substantially tubular geometric shape and avoid collapse of the lumen 1102. That is, in some embodiments, aqueous humor flowing through the lumen 1102 of the tubular element 1100 acts in such a way as to expand the lumen 1102. Thus, despite being soft and flexible, the tubular element 1100 is sufficient to act as a conduit for draining aqueous humor from the anterior chamber of the eye under appropriate conditions, such as an increase in intraocular pressure requiring the implantation of an ocular drainage system 1000. In various embodiments, because the tubular element 1100 is soft and flexible, it can adapt to the curvature of the eye and act in such a way as to avoid interference with normal eye functions (e.g., rotation and blinking).

[0071] Referring here to Figure 5, an ophthalmic drainage system 1000 is shown, comprising a tubular element 1100 consistent with the tubular element 1100 described above, and a sheath 1200 positioned around the tubular element 1100. The sheath 1200 is configured to promote or allow cell invasion and tissue adhesion, consistent with the above discussion regarding cell invasion and tissue adhesion in the tubular element 1100. That is, like the tubular element 1100, the sheath 1200 may be formed from a biocompatible material, the biocompatible material containing a plurality of pores of a size that promotes and / or allows cell invasion and tissue adhesion. In some embodiments, the sheath 1200 may include microstructures that exhibit properties that promote / allow cell invasion and tissue adhesion. Alternatively, the sheath 1200 may be configured to resist cell invasion and tissue adhesion.

[0072] In some embodiments, the sheath 1200 may include one or more layers or sheets of stretched polytetrafluoroethylene (ePTFE). However, these layers or sheets may be formed from other polymers, which may include, but are not limited to, polyurethane, polysulfone, polyvinylidene fluoride (PVDF), polyhexafluoropropylene (PHFP), perfluoroalkoxy polymer (PFA), polyolefin, fluorinated ethylene propylene (FEP), acrylic copolymer, and polytetrafluoroethylene (PTFE). These materials may be in the form of sheets, knitted fabrics, woven fabrics, or nonwoven fabrics. In some embodiments, the sheath 1200 may be formed from multiple layers or sheets of polymer material. In some such embodiments, the layers or sheets may be laminated or mechanically bonded by heat treatment and / or high-pressure compression and / or adhesives and / or other lamination methods known to those skilled in the art.

[0073] In some embodiments, the layer or sheet of polymer material forming the sheath 1200 is subjected to one or more processes for modifying the microstructure (and therefore the material properties) of the layered polymer material. In some embodiments, such processes include, but are not limited to, material coating processes, surface preconditioning processes, and / or drilling processes consistent with the above discussion.

[0074] The sheath 1200 may be permeable to ophthalmic fluid (e.g., aqueous humor) or may be configured to be more permeable to ophthalmic fluid by a perforation process and / or by the naturally occurring microstructure of the polymer forming the sheath 1200. In some embodiments, the sheath 1200 may include pores having an average size of about 20 microns to about 100 microns, or about 40 to about 80 microns. In other embodiments, the pore size (or average size) may exceed 100 microns or 150 microns.

[0075] In some embodiments, after positioning one of the first and second ends 1104 of the tubular element 1100 within the anterior chamber, the tubular element 1100 can be fixed to the surrounding tissue to help minimize the risk of the tubular element 1100 falling out of the anterior chamber. In some embodiments, one or more stitches are used to bond the tubular element 1100 (and thus the ocular drainage system 1000) to the ocular tissue. In some embodiments, a biocompatible tissue adhesive can be used. In other embodiments, a needle track created through the tissue to provide access to the anterior chamber in connection with the implantation procedure of the tubular element can be sufficiently sized to provide an interfacial fit capable of holding the tubular element 1100.

[0076] While the tubular elements 1100 exemplified and described herein generally include circular cross-sections, it should be understood that the tubular elements 1100 may have cross-sections of any suitable shape without departing from the spirit or scope of this disclosure. For example, the tubular elements 1100 may include cross-sections that are oval, square, rectangular, trapezoidal, or any other polygonal shape, such that they do not interfere with normal eye function.

[0077] In some embodiments, the ocular drainage system 1000 may further include a rigidifying member that is detachably integrated with the tubular element 1100. The rigidifying member (not shown) helps to assist in the delivery of the tubular element 1100, because the flexible and adaptable nature of the tubular element 1100 makes its advance through anatomical structures difficult. Therefore, the detachable rigidifying member works with the tubular element 1100 to temporarily form an installation assembly having a column strength exceeding that of the tubular element 1100. Forming an installation assembly with such increased column strength helps to assist in the delivery / implantation procedure of the ocular drainage system 1000. Such installation assemblies also help provide delivery of the ocular drainage system 1000 that is adaptable and operable to conform to the profile of the tissue (e.g., ocular tissue) and the anatomical structure into which the ocular drainage system 1000 is implanted, while maintaining a minimal profile to avoid stimulation and / or interference from normal bodily functions (e.g., blinking).

[0078] A stiffening member having sufficient columnar strength to allow advancement within an anatomical structure assists in enabling the advancement of the tubular element 1100 within the anatomical structure. Once properly positioned within the anatomical structure, the stiffening member can be removed in place from the tubular element 1100 without requiring the tubular element 1100 to be removed from its position within the anatomical structure. In some embodiments, the stiffening member may be a long element located inside and / or around the tubular element 1100. The long element may be coiled or extend longitudinally (e.g., in the form of a mandrel). For example, the stiffening member may be in the form of a coiled suture.

[0079] The stiffening member may include silicone, ePTFE, polycarbonate, polyethylene, polyurethane, polysulfone, PVDF, PHFP, PFA, polyolefin, FEP, acrylic copolymer and other suitable fluoropolymers, or any other suitable polymer, or a metallic component such as stainless steel or nitinol (straight or braided). It is understood that by changing the material properties of the stiffening member and / or gauge, stiffening members with desired axial, transverse, and / or radial stiffness can be produced. In other embodiments, the stiffening member may be formed from excisable or absorbable material, additionally or alternatively. The ocular drainage system 1000 may be formed from a stiffening member detachably coupled to a tubular element 1100, or the stiffening member may be inserted into the tubular element 1100 by the user before the implant procedure. The stiffening member may then be removed or detached from the tubular element 1100 after the implant procedure.

[0080] Looking at Figures 6A and 6B, detailed views of a portion of the tubular element 1100 of the ophthalmic drainage system 1000 are shown. The tubular element 1100 shown in Figures 6A and 6B includes a helical winding structure in which adjacent helices overlap in overlap regions 1112. Although the amount of overlap in each overlap region 1112 is shown to be the same, it should be understood that the amount of overlap can be varied. For example, the amount of overlap can be varied to change properties (e.g., structural integrity) along different portions of the tubular element 1100. The overlap region generally includes an inner layer and an outer layer, for example, the outer layer and inner layers 1114 and 1116 shown in Figures 6A and 6B. Adjacent helices are generally joined together along the overlap region so that adjacent helices are joined along the interface between their respective inner and outer layers, except for one or more distinct regions, leaving some of the interface between the inner and outer layers of adjacent helices unjoined. That is, only a portion of the inner layer 1116 in the overlapping region is coupled to the outer layer 1114. For example, only a portion of the inner layer 1116 in the overlapping region 1112 is coupled to the outer layer 1114. In a designated uncoupled region, the inner layer 1116 can bend radially inward from the outer layer 1114 (as shown in Figure 6B) to act as a limiter (or valve) in response to fluid flowing through the tubular element 1100 in an undesirable direction (e.g., backflow). That is, in various embodiments, the inner layer 1116 is configured to bend radially inward from the outer layer 1114 under backflow conditions, approaching the overlapping region 1112 or reducing the diameter of the tubular element 1100 in the overlapping region 1112, thereby reducing, minimizing, or obstructing backflow.

[0081] In various embodiments, the tubular element 1100 is formed by helically winding a material to form an overlapping region, as shown in Figure 6A, such that the exposed leading edge of the inner portion of the overlapping region faces downstream under normal operating conditions (e.g., when ophthalmic fluid is flowing through the tubular element 1100 in the direction of arrow 1118). That is, the material forming the tubular element 1100 is helically wound such that the inner layer 1116 extends beneath the outer layer 1114 in the direction of ophthalmic fluid flow under normal operating conditions (e.g., aqueous humor flowing along arrow 1118).

[0082] Figure 6A shows the tubular element 1100 under normal flow operation, where aqueous humor flows out of the anterior chamber (AC) of the eye and away from the anterior chamber (AC) through the tubular element 1100. Conversely, Figure 6B shows the tubular element 1100 under abnormal flow operation, where aqueous humor flows backward through the tubular element 1100 towards the anterior chamber (AC) of the eye in the direction of arrow 1120. As shown in Figure 6B, when aqueous humor flows backward through the tubular element 1100 towards the anterior chamber (AC) of the eye in the direction of arrow 1120, the unconnected portions of the inner layer 1116 flex radially inward from the outer layer 1114, as shown. These flexed unconnected portions of the inner layer 1116 then act to help prevent, reduce, or otherwise minimize the flow velocity of the regurgitation (or reverse flow) of aqueous humor returning to the anterior chamber (AC) of the patient's eye through the tubular element 1100.

[0083] In some embodiments, the ocular drainage system 1000 is implantable from the outside (e.g., from the outside of the eye), such as through a conjunctival incision. In some embodiments, a radial incision of the conjunctiva is typically made near the limbal junction, and a blunt incision of the conjunctiva is made to expose the sclera and provide a site for the placement of the ocular drainage system 1000. In some embodiments, this may require suturing one or more portions of the ocular drainage system (e.g., tubular element 1100) to the sclera. In some embodiments, a small needle, such as a 22 or 23 gauge needle, is also inserted near the scleral promontory to provide a track for inserting and positioning the tubular element 1100 into the anterior chamber.

[0084] In various embodiments, one or more parts of the ocular drainage system 1000 may contain or be coated with one or more therapeutic agents, such as drugs for treating glaucoma.

[0085] In some embodiments, the ocular drainage system 1000 includes one or more erosion elements (not shown) extending adjacent to a portion of the tubular element 1100, which helps minimize the possibility of erosion of the tubular element 1100 through the ocular tissue when the ocular drainage system 1000 is implanted. In some embodiments, the erosion element is a plate located between the tubular element 1100 and the surrounding tissue, so that micro-movements of the tubular element 1100 occur between the tubular element 1100 and the erosion element, while the erosion element remains stationary relative to the ocular tissue. Thus, the erosion element acts as a protective barrier between the tubular element 1100 and the tissue. The erosion element may be integral with the tubular element 1100 or may be attached to it via one or more fastening elements, such as one or more sutures, adhesives, etc. In some embodiments, the erosion element may include any material discussed herein as suitable for the tubular element 1100.

[0086] In some embodiments, the tubular element 1100 of the ophthalmic drainage system 1000 is initially partially or completely blocked by one or more resistance elements (not shown) that are removably placed within one or more lumens of the tubular element 1100, so that the fluid flow through the tubular element 1100 is initially blocked or reduced by the resistance elements. These resistance elements can later be removed from the tubular element 1100 to increase the fluid flow velocity through the tubular element 1100 compared to the flow velocity through the tubular element 1100 before the removal of the resistance elements.

[0087] In some embodiments, the resistance element may be bioabsorbable so as to be configured to biodegrade over time, for example, by interacting with bodily fluids (e.g., aqueous humor). Additionally or alternatively, the resistance element may be configured to be removed by some physical intervention, including physical retrieval by a physician, and / or by ablation with a high-energy source (e.g., laser). In embodiments in which the tubular element 1100 may include multiple lumens (e.g., the tubular element is formed by multiple lumens, or the tubular element is formed from multiple individual elements having lumens that collectively form the tubular element 1100), the resistance element may be initially placed inside one or more of the multiple lumens so as to block or reduce the flow through the lumens, thereby reducing the flow velocity through the tubular element 1100 compared to the flow velocity through the tubular element 1100 when the resistance element is removed from one or more lumens.

[0088] In certain embodiments, an ocular drainage system 1000 can be implanted to reduce intraocular pressure caused by the accumulation of excess ocular fluid. The ocular drainage system allows excess ocular fluid to be drained from the anterior chamber and reabsorbed. In certain embodiments, an ocular drainage system 1000 can be implanted to alleviate or treat symptoms of ocular hypertension or glaucoma. In such embodiments, the ocular drainage system 1000 may be configured to drain aqueous humor from the anterior chamber of the patient's eye. [Examples]

[0089] Example 1 First, an ePTFE film approximately 0.150 inches wide was spirally wound onto a silver-plated copper core wire approximately 0.010 inches in diameter, resulting in a coating of approximately five layers of ePTFE. Next, the wound structure was heat-treated in a convection air oven at 360°C for approximately 10 minutes. Once cooled, the core wire was withdrawn and removed, leaving the patented ePTFE tube.

[0090] Secondly, a small batch of two-part silicone (Nusil Inc., Grade 4840 Carpinteria, CA 93013) was prepared to obtain a thick, viscous fluid. This fluid was diluted 50% with n-heptane and thoroughly mixed.

[0091] Thirdly, silicone fluid was injected into the ePTFE tube using a syringe fitted with a 25-gauge needle. Next, a 0.010-inch straight wire was inserted into the fluid-filled tube. The assembly was then subjected to heat treatment at 115°C for approximately 15 minutes. Once cooled, the straight wire was removed, leaving the patented watertight ePTFE tube with an exterior configured to allow internal tissue growth.

[0092] Example 2 First, an ePTFE film approximately 0.070 inches wide was spirally wound onto a silver-plated copper core wire approximately 0.005 inches in diameter, resulting in a coating of approximately two layers of ePTFE. Next, the wound structure was subjected to heat treatment at 360°C for approximately 10 minutes in a convection air oven.

[0093] Secondly, a small batch of two-part silicone (Nusil Inc., Grade 4840 Carpinteria, CA 93013) was prepared to obtain a thick, viscous fluid. This fluid was diluted to approximately 50% with n-heptane (Item 246654, Sigma-Aldrich Corp., St. Luois, MO) and thoroughly mixed.

[0094] Thirdly, the wrapped mandrel was then held under horizontal tension and coated with an excess of the viscous silicone mixture. The coated wrapped mandrel was then passed through the thumb-index finger joint to measure out the excess silicone, which still provided a coated outer surface.

[0095] Fourth, an ePTFE film approximately 0.070 inches wide was helically wound onto a coated, wound mandrel. This assembly was then subjected to a heat treatment at 115°C for 15 minutes. Once cooled, the straight wire was removed, leaving a patented watertight ePTFE tube with an exterior configured to allow internal tissue growth.

[0096] The scope of the present invention in this application has been described both generally and with respect to specific embodiments above. It will be apparent to those skilled in the art that various modifications and variations can be made in the embodiments without departing from the scope of this disclosure. Similarly, the various components discussed in the embodiments discussed herein can be combined. Therefore, the embodiments are intended to cover modifications and variations within the scope of the present invention.

Claims

1. a compliant fluid conduit implantable within or between tissues of an eye, the compliant fluid conduit comprising a single layer of material having a microstructure with portions of varying porosity, the single layer having a first end, a second end, and a lumen therebetween, and an exterior surface; a first portion of the microstructure including the exterior surface and including a plurality of pores having an average pore size between 40 microns and 80 microns configured to permit cellular ingrowth; a second portion of said microstructure including a luminal wall surface and including a plurality of pores having an average pore size of less than 2 microns configured to resist cellular ingrowth; Including, the first end is insertable into or near a chamber of the eye to allow aqueous humor to drain from the eye; and The second end is configured to be insertable into the ophthalmic venous system to allow ocular fluid drained from the eye to flow directly into the ophthalmic venous system.

2. The medical device of claim 1, wherein the first portion of the microstructure is at least partially located on the outer surface of the conformable fluid conduit.

3. The medical device of claim 2, wherein the second portion of the microstructure is at least partially located on the luminal wall surface.

4. A medical device as described in any one of claims 1 to 3, wherein the conformable fluid conduit is a polymer tube.

5. The medical device of claim 4, wherein the conformable fluid conduit comprises multiple layers.

6. The medical device of claim 4, wherein the polymer tube comprises a fluoropolymer.

7. The medical device of claim 6, wherein the polymer tube comprises expanded polytetrafluoroethylene.

8. The medical device of any one of claims 1, 2 or 4-7, further comprising a valve configured to regulate the rate at which fluid flows through the conformable fluid conduit.

9. The medical device of claim 8, wherein the valve is formed from a helical winding that is partially unbonded at the interface between inner and outer layers of material forming the compliant fluid conduit, and wherein the valve is configured to regulate the backflow rate of fluid passing through the compliant fluid conduit in a direction toward the anterior chamber of the eye.

10. The medical device of claim 9, wherein the valve is integrated into the compliant fluid conduit so that the valve and the compliant fluid conduit form a monolithic unit. vinegar.

11. A medical device as described in any one of claims 1, 2, 4, 7, 9 or 10, further comprising a sheath disposed around the conformable fluid conduit, the sheath defining the outer surface of the conformable fluid conduit.

12. A medical device as described in any one of claims 1, 2, 4, 7, 9 or 10, wherein the second end of the conformable fluid conduit is configured to be inserted into an episcleral vein of the eye.

13. A medical device as described in any one of claims 1, 2, 4, 7, 9 or 10, wherein the conformable fluid conduit is a synthetic polymeric material that is non-bioabsorbable.

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