Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 SULCUS TUBE INTERNAL NEEDLE TECHNIQUE (STINT) AND STINT DEVICE CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims priority to U.S. Provisional Application No.63/597,565 filed November 9, 2023, the content of which (text, drawings, and claims) is incorporated herein by reference. FIELD [0002] The present teachings relate to ophthalmology and more particularly to a device and method for treatment of glaucoma. BACKGROUND [0003] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. [0004] Glaucoma is a degenerative optic nerve disease characterized by irreversible vision loss. Its prevalence increases with age, and to date, the only known therapy to prevent its progression is lowering intraocular pressure. Appropriate therapies thus include eyedrops, laser therapy, or surgical interventions. [0005] Despite the emergence of micro-invasive glaucoma surgery, glaucoma drainage device implantation remains a cornerstone of surgical treatment options. While placing a drainage tube in the eye’s anterior chamber does reduce intraocular pressure, it also poses risks to corneal endothelial cells. Ciliary sulcus tube placement is promising in this regard, as it can reduce damage to endothelial cells. However, achieving proper sulcus placement can be challenging, as the sulcus cannot be directly visualized externally. This can ultimately increase the risk of corneal, zonular, or iris damage during and after surgery, and can result in difficulty maintaining intraocular pressure control. [0006] Treatment options are typically considered in order of increasing invasiveness. Eye drops, being the least invasive, are usually the first line of treatment. These include medications that increase aqueous outflow (prostaglandins, Rho kinase inhibitors, nitric oxides, and miotic or cholinergic agents) and medications that decrease aqueous production (alpha-adrenergic
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 agonists, beta blockers, and carbonic anhydrase inhibitors). However, these medications can cause side effects like eye discomfort, vision changes, and systemic symptoms. [0007] Laser treatment, specifically trabeculoplasty, is an example of a more invasive treatment. It targets the trabecular meshwork, using laser energy to enhance eye fluid drainage and lower intraocular pressure. While more invasive than medication, it is less invasive than traditional surgery. However, it may induce inflammation and does not permanently control intraocular pressure. [0008] Surgical intervention is typically a last resort due to its invasive nature. Options include trabeculectomy, which involves making a small opening in the eye to allow fluid egress, though it can result in an eye pressure that is too low and result in other long-term complications such as leaks and infection. Glaucoma implant surgery involves placing a drainage tube either in the anterior chamber or the ciliary sulcus. Posterior sulcus placement is generally preferred due to having less impact on the cornea, but it is much more technically challenging when using standard techniques. Minimally invasive glaucoma surgery (MIGS) has emerged as an alternative, employing techniques such as using micro-shunts and angle-based surgeries that modify the eye's drainage canals, though MIGS has limited intraocular pressure-lowering effectiveness. [0009] The eye is divided into anterior and posterior segments. The anterior segment comprises the sulcus (located between the lens and iris) and the anterior chamber (situated between the iris and cornea). Both of these chambers are filled with aqueous humor, a watery fluid. In contrast, the space posterior to the lens contains vitreous humor, a gelatinous substance. [0010] The eye possesses a natural 'outflow' pathway for aqueous fluid drainage. Filtration surgery aims to create a new outflow pathway when this natural mechanism is compromised. A common surgical technique is tube shunt surgery, which involves placing a silicone tube shunt through a wall of the eye, with the tube shunt connected to a drainage reservoir. The tube is typically inserted into the anterior chamber of the eye. [0011] To effectively drain aqueous fluid from the anterior segment, the tube shunt must be placed in either the anterior chamber or the sulcus. Anterior chamber placement is more common due to better visibility; surgeons can observe
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 the needle and its path through the clear cornea. Sulcus placement, while potentially beneficial, presents greater challenges due to the narrower space and limited external visibility due to the presence of the iris. [0012] Much literature has highlighted the negative effects of anterior chamber tube placement on corneal endothelial cells, which line the posterior surface of the cornea. The corneal endothelial cells are responsible for maintaining the clarity of the cornea, and their compromise can result in corneal swelling and decreased vision. In contrast, sulcus placement demonstrates a lower risk of endothelial cell loss and corneal decompensation, as the iris separates the tube from the corneal endothelium. [0013] Despite these advantages, the technical difficulty of sulcus placement remains a significant barrier to its widespread adoption. The traditional method involves pharmacologically dilating the pupil and passing a needle through the eye wall from exterior to interior until it enters the sulcus space. The needle is then withdrawn, and the tube shunt is fed through the opening. However, this approach can be problematic due to the blind nature of the initial entry, making it challenging to ensure proper alignment with the sulcus space, and increasing the risk of damage to structures including the cornea, iris, ciliary body, and zonules. [0014] Thus, there exists a need in the art for implements and techniques that facilitate drainage tube placement in the sulcus space. SUMMARY [0015] This summary is provided merely for purposes of summarizing various example embodiments of the present disclosure so as to provide a basic understanding of various aspects of the teachings herein. Various embodiments, aspects, and advantages will become apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the described embodiments. Accordingly, it should be understood that the description and specific examples set forth herein are intended for purposes of illustration only and are not intended to limit the scope of the present teachings. [0016] A device for placing a glaucoma drainage tube into the sulcus of an eye is described herein. The device comprises a needle that comprises a
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 hub and a shaft such that the shaft extends from the hub. The shaft comprises a proximal portion extending from the hub and terminating in a first bend, a medial portion extending from the first bend and terminating at a second bend, and a distal portion originating at the second bend and terminating at a tip. The distal portion has an ultra-thin outer wall and an inner diameter defining a lumen. [0017] The first bend forms a first angle between the proximal portion and the medial portion, the first angle being between 35° and 55°. The second bend forms a first angle between the medial portion and the distal portion, the second angle being between 35° and 55°. The first angle and the second angle differ from one another by 5° or less, such that the proximal portion and the distal portion are substantially parallel. Furthermore, the proximal portion and the distal portion are offset from one another by between 1.0 and 3.0 mm. A width ratio defined by dividing the thickness of the ultra-thin outer wall and the inner diameter of the distal portion is between 0.04 and 0.07. [0018] The proximal portion and the medial portion can also have outer walls that can be as thick as or thicker than the outer wall of the distal portion. Alternatively, the proximal portion and the medial portion can be substantially solid. [0019] A method of using the device to implant a drainage tube shunt into an eye, referred to as the sulcus tube internal needle technique (STINT), is also described herein. The method comprises making an incision site on the peripheral cornea of the eye, passing the needle shaft through the incision site until the distal portion of the shaft is disposed in the ciliary sulcus of the eye and piercing the sclera of the eye with the distal portion of the shaft at an exit puncture site. The method then comprises inserting a leading end of a tube shunt into an inner lumen of the distal portion of the shaft such that the leading end is disposed within the distal portion of the shaft, withdrawing the distal portion of the shaft having the leading end of the tube shunt disposed therein into the ciliary sulcus, thereby carrying the leading end of the tube shunt into the ciliary sulcus, holding the tube shunt in place while withdrawing the shaft to remove the tube shunt from the inner lumen of the distal portion, and fully withdrawing the shaft from the eye.
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 [0020] When the distal portion of the shaft is disposed in the ciliary sulcus, the proximal portion of the shaft is disposed partly within the anterior chamber of the eye and partly outside of the eye. The incision site and the puncture exit site can be on substantially opposite sides of the eye, and the puncture exit site is between 2.0 and 2.5 mm posterior of the incision site. The tube shunt has an outer diameter between 80% and 100% of the inner diameter of the distal portion of the shaft. [0021] The pupil can be dilated prior to making an incision at the incision site. Additionally, prior to passing the shaft of the needle through the incision site, an ophthalmic viscoelastic device can be injected into the ciliary sulcus. BRIEF DESCRIPTION OF DRAWINGS [0022] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present teachings in any way. [0023] FIG. 1A exemplarily provides a side view of a double-bend needle in accordance with various embodiments of the present disclosure. [0024] FIG.1B exemplarily provides an angled view of a double-bend needle in accordance with various embodiments of the present disclosure. [0025] FIG.2A exemplarily provides an enlarged view of the medial and distal portions of a double-bend needle in accordance with various embodiments of the present disclosure. [0026] FIG. 2B exemplarily provides an enlarged view of a double- bend needle tip in accordance with various embodiments of the present disclosure. [0027] FIG. 2C provides, for the purposes of comparison, an enlarged view of an exemplary typical needle tip as known in the prior art. [0028] FIG. 2D exemplarily provides an enlarged cross-sectional view of a double-bend needle in accordance with various embodiments of the present disclosure. [0029] FIG. 2E exemplarily provides an enlarged cross-sectional view of a double-bend needle featuring a proximal portion and a medial portion
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 that have smaller inner diameters in accordance with various embodiments of the present disclosure. [0030] FIG.2F exemplarily provides an enlarged cross-sectional view of a double-bend needle wherein the proximal portion and medial portion are not hollow, in accordance with various embodiments of the present disclosure. [0031] FIG.3A exemplarily provides a schematic of the anatomy of an eye, and particularly of the location of an incision site in accordance with various embodiments of the methods of the present disclosure. [0032] FIG.3B exemplarily depicts the placement of the distal portion of the thin-walled double-bend needle in through the incision site in accordance with various embodiments of the methods of the present disclosure. [0033] FIG.3C exemplarily depicts the placement of the thin-walled double-bend needle in the sulcus space in accordance with various embodiments of the methods of the present disclosure. [0034] FIG. 3D exemplarily depicts passing the thin-walled double- bend needle through a side of the eye opposite the incision site, in accordance with various embodiments of the methods of the present disclosure. [0035] FIG.3E exemplarily depicts the insertion of the tube shunt into the distal portion of the shaft of the double-bend needle in accordance with various embodiments of the present disclosure. [0036] FIG. 3F exemplarily depicts withdrawal of the tip of the thin- walled double-bend needle back into the eye, bringing the tube shunt therewith into the sulcus space, in accordance with various embodiments of the methods of the present disclosure. [0037] FIG. 3G exemplarily depicts the tube shunt disposed in the sulcus space after the thin-walled double-bend needle has been fully withdrawn from the eye through the incision site in accordance with various embodiments of the present disclosure. [0038] Corresponding reference numerals indicate corresponding parts throughout the several views of drawings. DETAILED DESCRIPTION
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 [0039] The following description is merely exemplary in nature and is in no way intended to limit the present teachings, application, or uses. Throughout this specification, like reference numerals will be used to refer to like elements. Additionally, the embodiments disclosed below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art can utilize their teachings. As well, it should be understood that the drawings are intended to illustrate and plainly disclose presently envisioned embodiments to one of skill in the art, but are not intended to be manufacturing level drawings or renditions of final products and may include simplified conceptual views to facilitate understanding or explanation. As well, the relative size and arrangement of the components may differ from that shown and still operate within the spirit of the invention. [0040] As used herein, the word "exemplary" or "illustrative" means "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" or "illustrative" is not necessarily to be construed as preferred or advantageous over other implementations. All of the implementations described below are exemplary implementations provided to enable persons skilled in the art to practice the disclosure and are not intended to limit the scope of the appended claims. [0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a”, "an”, and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", “including”, and “having” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps can be employed. [0042] When an element, object, device, apparatus, component, region or section, etc., is referred to as being "on”, “engaged to or with”, "connected to or with”, or "coupled to or with" another element, object, device, apparatus, component, region or section, etc., it can be directly on, engaged, connected or coupled to or with the other element, object, device, apparatus, component, region or section, etc., or intervening elements, objects, devices, apparatuses, components, regions or sections, etc., can be present. In contrast, when an element, object, device, apparatus, component, region or section, etc., is referred to as being "directly on”, “directly engaged to”, "directly connected to”, or "directly coupled to" another element, object, device, apparatus, component, region or section, etc., there may be no intervening elements, objects, devices, apparatuses, components, regions or sections, etc., present. Other words used to describe the relationship between elements, objects, devices, apparatuses, components, regions or sections, etc., should be interpreted in a like fashion (e.g., “between” versus “directly between”, “adjacent” versus “directly adjacent”, etc.). [0043] As used herein the phrase “operably connected to” will be understood to mean two are more elements, objects, devices, apparatuses, components, etc., that are directly or indirectly connected to each other in an operational and/or cooperative manner such that operation or function of at least one of the elements, objects, devices, apparatuses, components, etc., imparts or causes operation or function of at least one other of the elements, objects, devices, apparatuses, components, etc. Such imparting or causing of operation or function can be unilateral or bilateral. [0044] As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. For example, A and/or B includes A alone, or B alone, or both A and B. [0045] Although the terms first, second, third, etc. can be used herein to describe various elements, objects, devices, apparatuses, components, regions or sections, etc., these elements, objects, devices, apparatuses, components, regions or sections, etc., should not be limited by these terms. These terms may be used only to distinguish one element, object, device, apparatus, component, region or
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 section, etc., from another element, object, device, apparatus, component, region or section, etc., and do not necessarily imply a sequence or order unless clearly indicated by the context. [0046] Moreover, it will be understood that various directions such as "upper", "lower", "bottom", "top", "left", "right", "first", "second" and so forth are made only with respect to explanation in conjunction with the drawings, and that components may be oriented differently, for instance, during transportation and manufacturing as well as operation. Because many varying and different embodiments may be made within the scope of the concept(s) taught herein, and because many modifications may be made in the embodiments described herein, it is to be understood that the details herein are to be interpreted as illustrative and non-limiting. [0047] The present disclosure generally provides a device for implanting a tube shunt into a ciliary sulcus region of an eye to relieve pressure within the eye (intraocular pressure) caused by a disease or condition such as glaucoma. Referring to FIGS.1A and 1B, the device comprises a thin-walled double-bend needle 100 that is structured to enable a novel surgical technique for treatment of intraocular pressure by virtue of having two bends and an ultra-thin outer wall. The two bends and ultra-thin outer wall of the thin-walled double-bend needle 100 provide several advantages over known, commercially available hypodermic needles. For example, most known commercially available hypodermic needles comprise entirely linear shafts, which can become problematic when a treatment requires a physician to move the known needle along a partially obscured and/or non-linear path through the eye. By contrast, the two bends in the thin-walled double-bend needle 100 of the present disclosure enable the physician to use the needle to confidently and safely navigate a partially obscured and/or non-linear path through the eye during treatment. Additionally, in various exemplary embodiments of the treatment methods of the present disclosure, the thin-walled double-bend needle 100 punctures the eye’s sclera. The ultra-thin outer wall of the thin-walled double-bend needle 100 allows the thin-walled double-bend needle 100 to accommodate a drainage tube inserted into the needle and ensures that damage to the eye from puncturing the eye’s sclera is minimized. Furthermore, as is detailed below, the ultra- thin outer wall also results in a puncture site that is nearly perfectly complementary
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 to a tube shunt, enabling drainage of excess fluid in the eye through the tube shunt while avoiding any leaking of excess fluid around an exterior of the tube shunt. [0048] Referring particularly to FIGS.1A and 1B, the thin-walled double- bend needle 100 comprises a needle hub 150 operably connected to a shaft 105 that originates at a proximal end 106 and terminates at a distal end 107. The shaft 105 is an elongate hollow member formed of a single continuous material comprising three portions, including a proximal portion 110, a medial portion 120 extending distally from the proximal portion 110, and a distal portion 130 extending distally from the median portion 120. In various exemplary embodiments, the proximal portion 110 originates at the proximal end 106, medial portion 120 extends distally from the proximal portion at a first bend 115, and the distal portion 130 extends distally from the medial portion 120 at a second bend 125. The distal portion 130 comprises a needle tip 140 and terminates at the distal end 107. [0049] Referring to FIG. 1A, in various exemplary embodiments, the shaft 105 of the thin-walled double-bend needle 100 has an offset profile. In other words, in various exemplary embodiments, the proximal portion 110 and the distal portion 130 can be substantially parallel, but not collinear, as they are offset from one another by an offset distance O1. The offset profile of the shaft 105 distinguishes the thin-walled double bend needle 100 from known hypodermic needles. Importantly, the offset profile of the shaft 105 enables a physician to confidently perform certain operations that require moving the tip 140 of the thin-walled double- bend needle 100 to a known location that the physician cannot see, such as behind an iris of an eye. So long as the physician knows the orientation of the thin-walled double-bend needle 100 and can see the location of the proximal portion 110 of the shaft 105, the physician can then infer the location of the tip 140, even if they cannot see it, by virtue of knowing the dimensions of the thin-walled double-bend needle 100 such as the offset distance O1. [0050] Dimensions such as the lengths of each portion of the thin-walled double-bend needle 100 and the angles of the first bend 115 and the second bend 125 are thus directly relevant to the physician and the operation being considered. Referring particularly to FIG.1A, the proximal portion 110 has a proximal length L1, the medial portion 120 has a medial length L2, and the distal portion 130 has a distal length L3. The proximal length L1 is measured from the proximal end 106 to the first
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 bend 115. The medial length L2 is measured from the first bend 115 to the second bend 125. The distal length L3 is measured from the second bend 125 to the distal end 107. The proximal length L1, the medial length L2, and the distal length L3 can each independently be any desired length known or envisioned to one of ordinary skill in the art to be useful in the treatment of glaucoma. In various exemplary embodiments, the proximal length L1 is greater than the distal length L3, and the distal length L3 is greater than the medial length L2. In various exemplary embodiments, the ratio of L1:L2:L3 can be approximately 30:1:7. [0051] For example, in various exemplary embodiments, the proximal length L1 can be between 10 and 50 mm, between 20 and 40 mm, or between 25 and 35 mm. More particularly, in various exemplary embodiments, the proximal length L1 can be approximately or exactly 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, 22 mm, 23 mm, 24 mm, 25 mm, 26 mm, 27 mm, 28 mm, 29 mm, 30 mm, 31 mm, 32 mm, 33 mm, 34 mm, 35 mm, 36 mm, 37 mm, 38 mm, 39 mm, 40 mm, 41 mm, 42 mm, 43 mm, 44 mm, or 45 mm. In various exemplary embodiments, the medial length L2 can be between 0.25 and 5 mm, between 0.5 and 2.5 mm, or between 1 and 1.5 mm. More particularly, in various exemplary embodiments, the medial length L2 can be approximately or exactly 0.5 mm, 0.75 mm, 1.0 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2.0 mm, 2.25 mm, 2.5 mm. In various exemplary embodiments, the distal length L3 can be between 4 and 10 mm, between 5 and 9 mm, or between 6 and 8 mm. More particularly, in various exemplary embodiments, the distal length L3 can be approximately or exactly 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, or 10.0 mm. In various exemplary embodiments, the sum of the proximal length L1, the medial length L2, and the distal length L3 can be between 15 mm and 60 mm, between 25 and 55 mm, or between 35 and 50 mm. More particularly, in various exemplary embodiments, the sum of the proximal length L1, the medial length L2, and the distal length L3 can be approximately or exactly 30 mm, 31 mm, 32 mm, 33 mm, 34 mm, 35 mm, 36 mm, 37 mm, 38 mm, 39 mm, 40 mm, 41 mm, 42 mm, 43 mm, 44 mm, or 45 mm. [0052] Referring particularly to FIG. 1B, in various exemplary embodiments, the proximal portion 110 and the distal portion 130 are substantially parallel, such that the proximal portion 110 and the distal portion 130 and do not
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 deviate from one another by more than 5°. The medial portion 120 is not parallel to the proximal portion 110 or to the distal portion 130. In various exemplary embodiments, a first angle A1 is measured between the proximal portion 110 and the medial portion. In various exemplary embodiments, the first angle A1 is defined by the extent to which the shaft 105 is bent at the first bend 115. The first angle A1 can be of any value greater than 0° and less than or equal to 90°. For example, in various embodiments the first angle A1 can be between 10° and 90°, between 15° and 85°, between 20° and 80°, between 25° and 75°, between 30° and 70°, between 30° and 65°, between 35° and 60°, or between 35° and 55°. More particularly, in various exemplary embodiments, the first angle A1 can be approximately or exactly 15°, 16°, 17°, 18°, 19°, 20°, 21°, 22°, 23°, 24°, 25°, 26°, 27°, 28°, 29°, 30°, 31°, 32°, 33°, 34°, 35°, 36°, 37°, 38°, 39°, 40°, 41°, 42°, 43°, 44°, or 45°, 46°, 47°, 48°, 49°, 50°, 51°, 52°, 53°, 54°, 55°, 56°, 57°, 58°, 59°, 60°, 61°, 62°, 63°, 64°, or 65°. In various exemplary embodiments, second angle A2 is measured between the medial portion 120 and the distal portion 130. In various exemplary embodiments, the second angle A2 is defined by the extent to which the shaft 105 is bent at the second bend 125. In various embodiments, the second angle A2 can be of any value greater than 0° and less than or equal to 90°. For example, in various embodiments the second angle A2 can be between 10° and 90°, between 15° and 85°, between 20° and 80°, between 25° and 75°, between 30° and 70°, between 30° and 65°, between 35° and 60°, or between 35° and 55°. More particularly, in various exemplary embodiments, the second angle A2 can be approximately or exactly 15°, 16°, 17°, 18°, 19°, 20°, 21°, 22°, 23°, 24°, 25°, 26°, 27°, 28°, 29°, 30°, 31°, 32°, 33°, 34°, 35°, 36°, 37°, 38°, 39°, 40°, 41°, 42°, 43°, 44°, 45°, 46°, 47°, 48°, 49°, 50°, 51°, 52°, 53°, 54°, 55°, 56°, 57°, 58°, 59°, 60°, 61°, 62°, 63°, 64°, or 65°. [0053] In various exemplary embodiments, the first angle A1 and the second angle A2 can be equal. In various embodiments, the first angle A1 and the second angle A2 can be different from one another by no more than 5°, for example, fewer than 5°, fewer than 4°, fewer than 3°, fewer than 2°, or fewer than 1°. [0054] Referring now to FIGS. 1A, 1B and 2A, the needle tip 140 is formed at a tip angle A3 at the distal end 107 of the distal portion 130. As shown in FIG.2A, the needle tip 140 has a tip surface 141. The tip angle A3 can be of any value known to one of ordinary skill in the art to be effective for use on a hypodermic
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 needle. For example, In various exemplary embodiments, the tip angle A3 can be between 0° and 90°, between 5° and 75°, between 10° and 60°, or between 15° and 45°. More particularly, in various exemplary embodiments, the tip angle A3 can be approximately or exactly 5°, 6°, 7°, 8°, 9°, 10°, 11°, 12°, 13°, 14°, 15°, 16°, 17°, 18°, 19°, 20°, 21°, 22°, 23°, 24°, 25°, 26°, 27°, 28°, 29°, or 30°. [0055] The offset distance O1 is a function of the length L2 of the medial portion as well as the magnitudes of the first angle A1 and the second angle A2. The offset distance can be of any value known to one of ordinary skill in the art to be effective for placement of the distal portion 130 of the shaft 105 in a desired position relative to the proximal portion 110. For example, in view of various exemplary embodiments of the STINT method described below, the distal portion 130 of the shaft 105 can be disposed in the eye between 0.5 and 3 mm posterior to the proximal portion 110. Thus, in various exemplary embodiments, the offset distance O1 can be between 0.5 and 3 mm, between 1 and 2.7 mm, or between 1.5 and 2.5 mm. More particularly, in various exemplary embodiments, the offset distance O1 can be approximately or exactly 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3.0 mm. [0056] Referring to FIG.2B, the shaft 105 has an outer diameter D2 that does not substantially change across the proximal portion 110, the medial portion 120, and the distal portion 130. The shaft, or at least the distal portion 130 thereof, comprises a wall 145 defining a hollow inner lumen 146, wherein at least the distal end portion has an inner diameter D1. Particularly, the inner diameter D1 and the outer diameter D2 define the needle shaft wall 145 having a thickness W1. The inner lumen 146 has a diameter that is equivalent to the wall inner diameter D1. Therefore, the inner diameter D1 and the outer diameter D2 define the wall thickness W1. More specifically, the wall thickness W1 of at least the distal end portion 130 of the needle shaft 105 is equal to one half of the difference between the outer diameter D2 and the inner diameter D1 (e.g., W1 = (D2-D1)/2). In various exemplary embodiments, the outer diameter D2 can be between approximately 0.020 inches and 0.036 inches (e.g., approximately 0.028 inches) and the distal inner diameter D1 can be between approximately 0.020 inches and 0.030 inches (e.g., approximately 0.025 inches), resulting in a wall thickness W1 between approximately 0.0010 inches and 0.0020 inches (e.g., 0.0015 inches). In various exemplary embodiments, the wall thickness
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 W1 can be between approximately 0.03 mm and 0.05 mm, between 0.032 and 0.048 mm, or between 0.034 and 0.046 mm. More particularly, the wall thickness W1 can be approximately or exactly 0.030 mm, 0.031 mm, 0.032 mm, 0.033 mm, 0.034 mm, 0.035 mm, 0.036 mm, 0.037 mm, 0.0375 mm, 0.038 mm, 0.039 mm, 0.040 mm, 0.041 mm, 0.042 mm, 0.043 mm, 0.044 mm, 0.045 mm, 0.046 mm, 0.047 mm, 0.048 mm, 0.049 mm, or 0.050 mm. [0057] As exemplarily illustrated in Figure 2C, it should be noted that the thickness W1 of the needle shaft wall 145, at least at the distal portion 130, is significantly thinner than the wall thickness of known commercially available hypodermic needles with similar outer diameters. This can be demonstrated by comparison of the distal portion 130 of the thin-walled double-bend needle shaft 105 to a typical known needle shaft 205, as shown in FIG.2C. For example, the known needle shaft 205 comprises an inner diameter D1’ and an outer diameter D2’, the inner diameter D1’ being visible at the needle tip 240. The inner diameter D1’ and the outer diameter D2’ of the typical known needle shaft define a needle shaft wall 245 with a thickness W1’ as well as a lumen 246, the diameter of the lumen 246 being equivalent to the inner diameter D1’. The thickness W1’ of the typical known needle shaft wall 245 is thus equal to half of the difference between the outer diameter D2’ and the inner diameter D1’. [0058] Importantly, as exemplarily illustrated in FIGS. 2B and 2C, in various instances the outer diameter D2 of the shaft 105 can be approximately equal to the outer diameter D2’ of a known hypodermic needle shaft 205. However, in such exemplary instances, the inner diameter D1 of the shaft 105 is greater than the inner diameter D1’ of the known needle shaft 205 such that the wall thickness W1 of the shaft 105, or at least the distal portion 130 thereof, is notably thinner than the wall thickness W1’ of known hypodermic needles. Another way to express this is by calculating a wall width ratio R1, expressed as a ratio of the width W1 to the outer
diameter D2, such that ^^ ^ ^^ ^^, where D2 and W1 are expressed in the same units. In various embodiments, the width ratio R1 of at least the distal portion 130 of the thin-walled double-bend needle 100 can be between 0.01 and 0.2, between 0.02 and 0.1, between 0.03 and 0.08, between 0.04 and 0.07, or between 0.05 and 0.06. For example, in various exemplary embodiments, the width ratio R1 can be
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 approximately or exactly 0.010, 0.015, 0.020, 0.025, 0.030, 0.035, 0.040, 0.045, 0.050, 0.055, 0.060, 0.065, 0.070, 0.075, 0.080, 0.085, 0.090, 0.095, or 0.100. [0059] In various exemplary embodiments, inner diameters of the medial portion 120 and the proximal portion 110 can be smaller than the inner diameter D1 of the distal portion. As exemplarily shown in the cross-sectional view of FIG.2D, the needle shaft proximal portion 110 has a proximal inner diameter D1a and the medial portion 120 has a medial inner diameter D1b. In various exemplary embodiments, the proximal inner diameter D1a, the medial inner diameter D1b and the distal inner diameter D1 can be equal, which can have the benefit of simplifying production of the thin-walled double-bend needle shaft 105. [0060] However, in various alternative embodiments, the mechanical strength and rigidity of the shaft 105 can be reinforced by having the proximal inner diameter D1a and/or the medial diameter D1b be smaller than the distal inner diameter D1. For example and as shown in FIG.2E, the proximal inner diameter D1a and the medial inner diameter D1b can be smaller than the distal inner diameter D1, resulting in a medial wall 121 having a medial wall thickness W3 and a proximal wall 111 having a proximal wall thickness W2. As the outer diameter D2 of the shaft 105 is the same across the proximal portion 110, the medial portion 120, and the distal portion 130, a relative decrease in the proximal inner diameter D1a and/or the medial inner diameter D1b would result in a relative increase in the proximal wall thickness W2 and/or the medial wall thickness W3. In such an alternative embodiment, the needle shaft proximal portion 110 and the medial portion 120 would thus have greater wall thicknesses W2 and W3, respectively, than the wall thickness W1 of the distal portion 130. This can improve the strength and rigidity of the shaft 105 as a whole. [0061] Further, in various alternative embodiments and as shown in FIG. 2F, the proximal portion 110 and the medial portion 120 can be completely solid, leaving only the distal portion 130 hollow. In such an alternative embodiment, the needle shaft proximal portion 110 and the medial portion 120 would thus have no inner diameters. This can further improve the strength and rigidity of the shaft 105 as a whole. [0062] The needle tip 140 can be of any shape, design, or geometry known to one of ordinary skill in the art. For example, in various embodiments, the
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 needle tip 140 can be a tri-beveled sharp lancet tip, which is advantageous for making clean cuts. The needle hub 150 can be of any shape, design, or geometry known to one of ordinary skill in the art that supports the shaft 105. For example, in various embodiments, the hub 150 can be a twist-on hub or a slip hub, and can be made from polypropylene, plated brass, stainless steel, or any other suitable material. The needle shaft 105 can be made from any material known to one of ordinary skill in the art. For example, in various embodiments, the shaft 105 can be made from stainless steel, titanium, or niobium. [0063] The thin-wall double-bend needle 100 of the present disclosure enables an ab interno method for glaucoma treatment referred to herein as the sulcus tube internal needle technique (STINT), the method being described below with reference to FIGS.3A-3D. FIG.3A provides general anatomical description of an eye 300, which offers context for the positions, orientations, and movements of the thin-walled double-bend needle 100 during the STINT. [0064] Referring to FIG. 3A, the eye 300 is generally defined by an anterior segment 301 and a posterior segment 302. For the purposes of this description, 'anterior' is defined as the direction towards the front of the eye, where a cornea 310 is located. Conversely, 'posterior' is defined as the direction towards the back of the eye, and posterior to the cornea 310, the eye 300 is surrounded by a sclera 303. The anterior segment thus comprises the cornea 310 having an interior surface of which is lined with a layer of endothelial cells 315. The cornea 310 further comprises a central cornea 311 and peripheral cornea 312. The central cornea 311 comprises a higher density of endothelial cells 315 than the peripheral cornea 312. The cornea 310 partially surrounds an anterior chamber 320 that is delimited posteriorly by an iris 330 that is attached to a ciliary body 340. The ciliary body 340 defines a cavity called the ciliary sulcus 360 and is connected to a lens 350 via a plurality of zonules 370. Thus, the ciliary space 360 is bound by the iris 330 anteriorly, the ciliary body 340 peripherally, and the lens 350, and particularly a lens- zonular complex, posteriorly. Posterior to the lens 350 is the posterior region 302 of the eye 300. [0065] In various embodiments and as depicted in FIGS. 3A-3G, the STINT method of the present disclosure is a method of placing a tube shunt 410 of a drainage device 400 into the ciliary sulcus 360 with minimal risk and damage to
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 the eye 300. In brief, the STINT method comprises making an incision at a corneal incision site 380, passing the thin-walled double-bend needle shaft 105 through the incision, using the tip 140 of the distal portion 130 to pierce the eye at an exit puncture site 390 located posterior and substantially diametrically opposite to the incision site 380 (e.g., approximately 160° to 200° opposite the incision site 380), coupling the shaft 105 to a tube shunt 410 of a drainage device 400, drawing the tube shunt into the sulcus 360 of the eye 300 through the exit puncture site 390, and then fully withdrawing the shaft 105 of the thin-walled double-bend needle 100 from the eye 300. The STINT method is described in greater detail below. [0066] In various embodiments, to initiate the STINT method, an incision is made at the incision site 380. In various embodiments, the incision site 380 is selected to be within the peripheral cornea 312 anterior to the iris 380, such that insertion of the thin-walled double-bend needle shaft 105 into the incision will allow the needle shaft 105 to pass through a pupil of the iris 330. The pupil is a central opening in the iris 330 that provides access to structures posterior to the iris 330 without injury to the iris. In various exemplary embodiments, the pupil can be dilated in order to expand the pupil, which can facilitate passage of the distal portion 130 of the needle shaft 105 through the pupil. Importantly, the incision site 380 is located at the peripheral cornea 312, as opposed to the central cornea 311, in order to minimize potential damage to the endothelial cells 315 and prevent corneal scarring. [0067] The incision is generally sized to permit the entry and passage of the thin-walled double-bend needle shaft 105 through the pupil and into the anterior chamber 320 of the eye. After the incision is made, the distal portion 110 of the shaft 105 is passed through the incision as shown particularly in FIG.3B. Then the medial portion 120 of the shaft is passed through the incision. Due to the second bend 125 between the medial portion 120 and the distal portion 130, passing the medial portion 120 through the incision causes the distal portion 130 to move posterior to the incision site 380, through the pupil of the iris 330 and into the sulcus 360 opposite the incision site 380, posterior to the iris 330, as exemplarily shown in FIG. 3C. Importantly, while the distal portion 130 is within the ciliary sulcus 360, it is kept parallel to a plane of the iris 330 in order to ensure that the tip 140 of the distal portion 130 does not contact and/or damage the iris 330 or the lens 350 or the zonules. The
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 physician cannot see through the iris 330 to visually confirm that the distal portion 130 remains parallel with the plane of the iris 330, but advantageously, the proximal portion 110 of the shaft 105 remains visible and is parallel to the distal portion 130. Thus, the physician can visually confirm the orientation of the proximal portion 110 in order to keep the distal portion 130 of the shaft 105 disposed in the ciliary sulcus 360 without contacting the iris 330 or the lens 350 or the zonules. The proximal portion 110 of the shaft is then passed through the incision site 380 and the needle shaft 105 is advanced until the tip of the distal portion contacts the puncture exit site 390, which is substantially diametrically opposite (for example, between 160° to 200°) and posterior to the incision site 380. [0068] Subsequently, the tip 140 pierces the sclera 303 of the eye at the exit puncture site 390. The thin-walled double-bend needle shaft 105 is subsequently pressed through the exit puncture site 390 until at least a portion of the tip 140 extends externally from the sclera 303, as shown exemplarily in FIG.3D. A diameter of the exit puncture site 390 is substantially equal to the outer diameter of the distal portion 130 of the needle shaft 105. For example, in various instances the diameter of the exit puncture site can be between 0.5 mm and 2 mm, between 0.65 mm and 1.6 mm, or between 0.8 and 1.3 mm. In various exemplary embodiments, the diameter of the exit puncture site 390 is approximately or exactly 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, or 2.0 mm. As set forth above, the exit puncture site 390 is generally diametrically opposed to the incision site 380(e.g., approximately 180°) substantially 180° from the incision site 380. More particularly, in various exemplary embodiments, the incision site 380 is made on a first side of the eye 305, and the exit puncture site 390 is located on a second side of the eye 306 approximately 160° to 200° (e.g., approximately 180°) opposite the first side of the eye. In various exemplary embodiments, the exit puncture site 390 is located between 1.0 and 3.0 mm posterior of the incision site 380, more particularly between 2.0 mm and 2.5 mm posterior of the incision site 380. In various exemplary embodiments, the exit puncture site 390 can be approximately or exactly 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3.0 mm posterior of the incision site 380.
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 [0069] Importantly, in various exemplary embodiments, the thin-walled structure of the distal portion 130 of the shaft 105 ensures that the exit puncture site 390 inflicts minimal damage to the sclera 303. In various exemplary embodiments wherein the needle tip 140 is a sharp cutting tip such as a tri-beveled lancet tip, the resulting exit puncture site 390 is clean and well-defined, reducing the risk of trauma and preventing inadvertent leakage of excess ocular fluid. Moreover, the thin-walled structure of the distal portion 130 allows for insertion of the tube shunt 410 (as described below), and also minimizes the size of the exit puncture site 390 in order to reduce postoperative peritubular flow. [0070] Once the distal portion 130 of the thin-walled double-bend shaft 105 has punctured and extends external to the sclera 303 at the exit puncture site 390, a leading end of the drainage device 400 is inserted into the internal lumen 146 of the distal portion 130 of the shaft 105, as exemplarily illustrated in Figure 3E. The leading end of the drainage device 400 generally comprises the tube shunt 410. The tube shunt 410 generally is a hollow elongated tube with an inner lumen and an outer diameter D3. As exemplarily illustrated in FIG.3E, the tube shunt 410 is sized such that the outer diameter D3 is approximately equal or slightly smaller than the distal inner diameter D1 of the distal portion 130 of the thin-walled double-bend needle shaft 105. Thus, when the tube shunt 410 is inserted into the lumen 146 of the distal portion 130, the tube shunt 410 fits snugly into the lumen 146, providing a friction fit. Importantly, the friction fit should not be so tight that it becomes difficult to insert the tube shunt 410 into the lumen 146. In various exemplary embodiments, the outer diameter D3 is between 75% and 80%, between 80% and 100%, between 85% and 100%, between 90 and 100%, or between 95% and 100% of the distal inner diameter D1. As described above, the tube shunt 410 is temporarily carried within the needle shaft distal portion 130 by inserting the tube shunt 410 directly into the lumen 146 of the distal portion 130. Importantly, in various exemplary embodiments, the thin-walled shape of the distal portion 130 of the shaft 105 ensures that the tube shunt 410 can be easily inserted into the lumen 146 of the distal portion 130, and also minimizes the size of the exit puncture site 390 in order to reduce postoperative peritubular flow. [0071] Turning to FIG.3F, once the leading end of the tube shunt 410 is disposed within the internal lumen 146 of the distal portion 130, the needle shaft 105
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 is carefully withdrawn back through the eye 300, carrying the tube shunt 410 within the internal lumen 146 of the needle shaft proximal portion 130, thereby carrying the tube shunt 410 into the ciliary sulcus 360 adjacent the exit punction site 390. In various exemplary embodiments, the physician withdraws the needle shaft 105 from the eye 300 while simultaneously pushing the tube shunt 410 to keep the tube shunt 410 inserted within the internal lumen 146 of the distal portion 130. As exemplarily illustrated in FIG.3F, withdrawal of the shaft 105 and simultaneous pushing of the tube shunt 410 guides the tube shunt 410 into the ciliary sulcus 360 of the eye 300. Thereafter, once the tube shunt 410 is oriented and positioned within the ciliary sulcus 360 as desired by the physician, the physician ceases and prevents further advancement of the tube shunt 410 into the ciliary sulcus 360 while continuing to withdraw the needle shaft 105, thereby withdrawing the tube shunt 410 from within the internal lumen 146 of the distal portion 130. For example, the tube shunt 410 is separated from the needle shaft distal portion 130 by gently pulling the needle shaft 105 out through the incision site 380 while holding the tube shunt 410 in place. Subsequently, the needle shaft 105 is withdrawn from the eye 300 entirely, leaving the tube shunt 410 implanted or disposed within the ciliary sulcus 360, as exemplarily shown in FIG.3G. With the tube shunt 410 properly disposed in the ciliary sulcus 360, excess pressure within the eye can be relieved by draining ocular fluid through the tube shunt 410. In various instances, a length of the tube shunt 410 can be trimmed as desired by the physician prior to inserting the tube shunt 410 into the lumen 146. [0072] Importantly, the thin-walled shape of the thin-walled double-bend needle at the distal portion 130 ensures that the diameter of the exit puncture site 390 is nearly equivalent to the outer diameter D3 of the tube shunt 410. Thus, when the tube shunt 410 is passed through the exit puncture site 390 and disposed in the ciliary sulcus 360, there is a tight fit between the outer diameter D3 of the tube shunt 410 and the exit puncture site 390, preventing ocular fluid from leaking out around the tube shunt 410. [0073] In various embodiments, the method can further comprise a filler step of injecting and filling the sulcus 360 and a volume between the iris 330 and the lens 350 with an ophthalmic viscoelastic device (OVD), which is a protective shell that can expand and maintain space between the iris 330 and the lens 350. The use
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 of an OVD to expand and maintain space between the iris 330 and the lens 350 can aid the physician in avoiding injury to the iris 330 and/or lens 350 and/or zonules while passing the distal portion 130 through the ciliary sulcus 360. In various embodiments, the filler step can be performed prior to making the incision at the incision site 380. In various embodiments, the filler step can be performed after making the incision at the incision site 380 but before passing the thin-walled double- bend needle through the incision site 380. Additionally, in various embodiments, the lens 350 can have been previously replaced with an artificial acrylic lens. [0074] In light of the various figures, one skilled in the art would readily recognize that the first bend 115 and the second bend 125 of the thin-walled double- bend needle shaft 105 enable a surgeon to make the incision at the incision site 380 in the peripheral cornea 312, but the needle shaft distal portion 130 will actually exit the opposite side of the eye substantially parallel to the iris 330 but more posteriorly within the eye 300 than the incision site 380 so that the distal portion 130 of the thin- walled double-bend needle 100 is anatomically aligned within the cilary sulcus 360. Importantly, the double-bend needle 100 punctures and exits the eye 300 from internally within the eye 300 (e.g, from within the ciliary sulcus 360) to the exterior of the eye 300. EXAMPLES Example 1: Extra-Thin Walled Needle Comparison [0075] A thin-walled double-bend needle according to the present description was fabricated and its dimensions were compared to commercially- available needles. Table 1 below provides a list of known needles of varying gauges in comparison with an exemplary thin-walled double-bend needle of the present description. The outer values provided to describe the exemplary thin-walled double-bend needle in Table 1 are purely for comparison and are non-limiting. Table 1 -- Needle Wall Thickness Comparison
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024
[0076] As shown in Table 1, the ratio of the outer diameter to the wall thickness for the exemplary double-bend needle is 0.054, which is nearly half of the ratio calculated in the 10 gauge needle. A comparison of the exemplary thin-walled double-bend needle in Table 1 to a 22 gauge needle, which has a similar outer diameter, shows that the wall thickness of the exemplary thin-walled double-bend needle is between one-quarter and one-fifth the wall width of the 22 gauge needle. [0077] Table 2 below provides comparisons between know needles, an exemplary STINT thin-walled double-bend needle of the present description, and various commercially available tube shunts that can couple with a STINT double- bend needle.
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 Table 2 -- Needle and Tube Shunt Measurements
Example 2: Surgery with Double-Bend Needle [0078] The following is a summary of multiple exemplary uses of the devices and methods of the present description. Sulcus tube shunt placement using the STINT followed placement of the tube shunt baseplate and possible tube ligation as necessary. The tube was trimmed with a posteriorly facing bevel using scissors at a length that allowed the tube to be visualized when the patient was dilated but avoided obscuration of the visual axis by the tube tip. A paracentesis was created 180 degrees away from the location of
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 desired tube entry. Cohesive viscoelastic was injected into the anterior chamber via the paracentesis and directed into the ciliary sulcus. The STINT device was placed through the paracentesis and directed into the ciliary sulcus, taking care to keep the distal bent section parallel with the iris plane. Counter traction on the sclera was used as the needle was advanced from the ciliary sulcus through the sclera. The tube shunt was then inserted into the lumen of the STINT device extrasclerally and the STINT device was slowly withdrawn bringing the tube shunt with the STINT device and guiding the tube shunt into the ciliary sulcus. Thereafter, the STINT device was removed from the eye leaving the tube shunt disposed in the ciliary sulcus. Once the tube was visualized in the pupil and good tube placement confirmed, closure proceeded per standard techniques, and at the conclusion of the case the cohesive viscoelastic in the anterior and posterior chambers was burped from the paracentesis. [0079] The intraoperative sequence of the surgical procedure incurred slight variations from case to case reflecting the unique surgical history and clinical condition of each eye. [0080] The STINT technique can reduce the risk of corneal damage. In a 2022 AGS survey, 90% of the surveyed glaucoma surgeons reported commonly utilizing the AC for tube placement, but 61% reported that the available evidence suggests the superiority of sulcus placement over the AC in terms of ECL. Interestingly, 77% of surgeons reported that they would convert to placing tubes in the sulcus if a randomized controlled trial were to show its superiority in preventing ECL. [0081] Known ab externo variations of sulcus tube placement have inherent challenges, primarily due to anatomical differences among eyes, leading to uncertainty in tube placement and potential complications such as hyphema, iris trauma, zonular damage, or vitreous loss. A 2021 retrospective review of 104 sulcus tubes demonstrated that using the traditional ab externo approach required reinsertion of the tube due to malposition in 41% of cases, and sulcus insertion could not be accomplished at all in 4% of cases. The ab interno techniques reduce some uncertainty regarding sulcus location but pose their own difficulties. These methods can be technically challenging to perform
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 or they necessitate the use of a larger gauge needle which increases the risk of unwanted peritubular flow and postoperative hypotony. [0082] The STINT is readily adoptable and can increase surgical precision and ease of sulcus tube placement. The STINT and double-bend needle can confer several advantages compared to previously known techniques. It utilizes an ab interno approach reducing uncertainty regarding the location of the ciliary sulcus. The STINT device (e.g., the ultra-thin-walled double-bend needle) allows for continual maintenance of the sulcus pathway and therefore less risk of inadvertent iris or zonular trauma. The ultra-thin-wall of the STINT device enables maximization of the lumen space to accommodate the tube shunt, while minimizing total exterior diameter to minimize excess peritubular flow. Lastly, the double-bend aids in positioning the tube shunt parallel to the iris. The STINT and STINT device of the present disclosure offer increased ease and surgical precision of sulcus placement. [0083] Generally, the needle is made from ultra-thin steel and is designed to maximize the inner diameter of the needle (to enable the drainage tube shunt to fit inside) while minimizing outer diameter (to minimize the size of the hole made by the needle). The needle also contains 2 bends to maximize ease of use in the eye while minimizing unintended damage. The STINT enables posterior drainage tube placement into the sulcus region of the eye by inserting the modified needle substantially 180 degrees from the tube placement site, then traversing the eye with the needle to create the tube entry site, using the cavity of the needle to guide the drainage tube [0084] The STINT represents a potentially safer approach for ciliary sulcus tube placement compared to traditional anterior chamber placement, which carries a higher risk of corneal, iris, or zonular damage. The STINT for glaucoma drainage device placement offers enhanced surgical precision, reduced corneal damage risk, and significant intraocular pressure reduction, with potential for decreased postoperative medication relative to baseline. The STINT aims to reduce the difficulty of properly placing glaucoma drainage device tubes into the ciliary sulcus, reduce the risk of corneal, iris, and zonular damage during and after surgery, and to improve surgical precision while maintaining effective intraocular pressure
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 control. For example, in various instances, the present STINT and STINT device reduces risk and simplifies glaucoma drainage surgery. [0085] The STINT is an alternative to traditional glaucoma implant surgery; specifically to replace anterior tube placement, and to improve the accuracy and outcomes associated with posterior sulcus placement. [0086] The description herein is merely exemplary in nature and, thus, variations that do not depart from the gist of that which is described are intended to be within the scope of the teachings. Moreover, although the foregoing descriptions and the associated drawings describe example embodiments in the context of certain example combinations of elements and/or functions, it should be appreciated that different combinations of elements and/or functions can be provided by alternative embodiments without departing from the scope of the disclosure. Such variations and alternative combinations of elements and/or functions are not to be regarded as a departure from the spirit and scope of the teachings.
[0076] As shown in Table 1, the ratio of the outer diameter to the wall thickness for the exemplary double-bend needle is 0.054, which is nearly half of the ratio calculated in the 10 gauge needle. A comparison of the exemplary thin-walled double-bend needle in Table 1 to a 22 gauge needle, which has a similar outer diameter, shows that the wall thickness of the exemplary thin-walled double-bend needle is between one-quarter and one-fifth the wall width of the 22 gauge needle. [0077] Table 2 below provides comparisons between know needles, an exemplary STINT thin-walled double-bend needle of the present description, and various commercially available tube shunts that can couple with a STINT double- bend needle.
Atty. Dkt. No. UMCO H495WO/17193-00182 Client Ref. No.24UMC024 Table 2 -- Needle and Tube Shunt Measurements