Devices, kits, and methods for minimally invasive glaucoma surgery

Abstract

The present invention relates to medicine and medical technology, in particular to a device for glaucoma treatment and a method of implanting such a device. The device is a drainage tube in the form of a self-expanding frame having a distal end and a beveled proximal end. The device is designed to be implanted from the outside of the eyeball inwards, from the conjunctiva to the anterior chamber of the eye, through a puncture in the sclera-corneal tissue at the level of the anterior chamber, so that the distal end of the drainage tube is located at the level of the eye's trabecular meshwork but does not protrude into the anterior chamber, and the proximal end is located at the boundary of the scleral and subconjunctival space but does not protrude into the subconjunctival space, wherein the frame self-expands along its entire length after implantation. The method comprises the following steps: selecting a pre-manufactured and sterilized kit, making a micro-incision in the conjunctiva, puncturing the sclera / corneal tissue through the micro-incision, wherein the puncture extends to the anterior chamber of the eye and forms a channel. This structure and method can reduce the intraocular pressure of patients with age-related retinopathy and maintain it within the normal range.

Description

Technical Field

[0001] This invention relates to medicine and medical technology, and particularly to a device for the treatment of glaucoma and a method for implanting such a device. This invention is used in the field of ophthalmology to reduce intraocular pressure in glaucoma patients. Background Technology

[0002] Glaucoma is an eye disease characterized by elevated intraocular pressure due to impaired aqueous humor outflow, leading to visual impairment and the development of glaucomatous optic neuropathy. The ultimate result of glaucoma is blindness caused by optic nerve atrophy.

[0003] With timely and adequate treatment, maintaining intraocular pressure at a safe level can keep the optic nerve unaffected throughout a patient's life. For this reason, some glaucoma patients require surgery to lower intraocular pressure. The routine procedure is called trabeculectomy. In trabeculectomy, a small opening is made in the front of the eye to allow aqueous humor to drain out. Alternatively, a shunt can be implanted inside the eye to create a channel for aqueous humor outflow. The shunt can be implanted externally, through the conjunctiva and into the sclera (lateral shunt), or internally, through the cornea, anterior chamber, trabecular meshwork, and sclera (intermediate shunt).

[0004] Known devices and implantation methods include CN108743016A, KR1020150159255A, US20192985572A1, US7879079, US8007459, US8377122, and US8545430.

[0005] Regarding the design of the shunt, the closest similar technology to the claimed invention is the solution disclosed in US8545430. In US8545430, the shunt is implanted through a corneal incision, the implantation site being either radially opposite to the incision or located on the same side as the incision. In the latter case, the delivery system is folded. The shunt is made of nitinol and has an expandable portion. The expandable portion has a first cylindrical cross-sectional diameter for insertion into the eye and a second elliptical cross-sectional diameter (larger than the first cylindrical cross-sectional diameter) for expanding or stretching tissue, and is configured to conform to the contour of Schlemm's canal to prevent the device from rotating during insertion. The distal end (located closer to the conjunctiva since implantation is performed from the inside out) is placed outside the sclera, not near the boundary between the sclera and conjunctiva. The proximal end is designed to be in fluid communication with Schlemm's canal.

[0006] However, implanting a shunt through corneal puncture into the anterior chamber of the eye increases the invasiveness of the procedure, thereby increasing surgical risks and potential complications. Furthermore, filter-type products and products with narrow channels for draining fluid from the anterior chamber are prone to clogging by pigment particles from shed iris tissue.

[0007] Therefore, it is necessary to improve the design of medical devices to allow aqueous humor to drain out in cases of elevated intraocular pressure.

[0008] The present invention aims to solve the above-mentioned problems. Summary of the Invention

[0009] The technical problem to be solved by this invention is to ensure that the intraocular pressure of glaucoma patients decreases steadily and remains within the normal range.

[0010] The technical achievement of this invention lies in the development of a drainage implantable device (micro-scaffold) and its implantation method in minimally invasive intervention. This method creates a channel for aqueous humor to flow out of the anterior chamber of the eye, so as to reduce the intraocular pressure of glaucoma patients to a normal value (10-20 mmHg) and maintain it within that range.

[0011] Miniature stents must meet the following requirements:

[0012] 1. The miniature stent must be fixed in the aqueous humor outflow duct of the anterior chamber of the eye.

[0013] 2. The problem of pigment particles clogging the proximal and distal ends of the micro-stent must be addressed.

[0014] 3. Miniature stents must prevent aqueous humor from flowing rapidly out of the anterior chamber of the eye.

[0015] Another technological achievement is the development of a kit for minimally invasive surgery to implant drainage devices.

[0016] The device used for minimally invasive glaucoma surgery is a drainage tube in the form of a self-expanding frame with distal and proximal tilted ends. This ensures the effectiveness of the technique. The device is designed to be implanted from the outside of the eyeball inward, from the conjunctiva to the anterior chamber of the eye. The distal end of the drainage tube is positioned at the level of the trabecular meshwork of the eye without protruding into the anterior chamber, and the proximal end is positioned at the boundary of the sclera and subconjunctival space without protruding into the subconjunctiva. The frame self-expands along its entire length after implantation.

[0017] In some embodiments of the invention, the bevel angle of the proximal end of the drainage tube is selected based on the horizontal position of the proximal end at the outer surface of the sclera.

[0018] In some embodiments of the present invention, the oblique angle is in the range of 30° to 60°, preferably 45°.

[0019] In some embodiments of the invention, the length of the drainage tube is taken as a value equivalent to the thickness of the scleral and corneal tissue, which starts from the level of the apex of the anterior chamber angle of the eye.

[0020] In some embodiments of the present invention, the length of the drainage tube is in the range of 1.0 mm to 3.0 mm.

[0021] In some embodiments of the present invention, the diameter of the frame in the open state is constant, ranging from 0.5 mm to 1.5 mm.

[0022] In some embodiments of the present invention, the frame is composed of a shape memory material, preferably of nitinol.

[0023] In some embodiments of the invention, the frame is mesh-like.

[0024] In some embodiments of the invention, at least a portion of the outer surface of the drainage tube is coated with at least one antiproliferative drug selected from mitomycin-C, 5-fluorouracil, sirolimus (rapamycin), probucol, dexamethasone, and antivascular endothelial growth factor agents.

[0025] In some embodiments of the invention, at least a portion of the outer surface of the drainage tube is coated with a mixture of an antiproliferative drug and a polymer, wherein the drug is selected from mitomycin C, 5-fluorouracil, sirolimus (rapamycin), probucol, dexamethasone, an antivascular endothelial growth factor agent, and the polymer is a biodegradable polymer selected from polylactic acid (polylactide), polylactic acid-glycolic acid copolymer, polylactic acid-caprolactone copolymer, or a durable polymer, such as a biocompatible fluoropolymer.

[0026] Furthermore, the minimally invasive glaucoma surgery kit ensures the technical effect. The minimally invasive glaucoma surgery kit includes the above-described device according to any embodiment of the present invention, a preloaded delivery system, the preloaded delivery system including a sheath and a stop guide, the drainage tube being compressed within the sheath, the sheath preventing the drainage tube from expanding, and the stop guide being located within the sheath and preventing the device from moving longitudinally within the sheath.

[0027] Furthermore, the minimally invasive glaucoma surgery method ensures the effectiveness of the technique, and the method includes the following steps:

[0028] Choose pre-manufactured and sterilized minimally invasive glaucoma surgical kits, ensuring that the length, diameter, and proximal bevel of the devices in the kit are matched to the individual characteristics of the patient's eye structure;

[0029] Perform conjunctival microdissection;

[0030] The sclera and corneal tissue are punctured through a micro-incision, allowing the puncture to reach the anterior chamber of the eye and form a cannula;

[0031] The sheath of the delivery system passes through the anterior chamber of the eye from the conjunctiva in the formed tube until the distal end of the sheath reaches the apex of the anterior chamber angle;

[0032] The sheath of the conveying system moves in the proximal direction, and the stop guide is held in place so that the device is released and expanded to the set diameter while being held in the formed tube.

[0033] In some embodiments of the present invention, conjunctival micro-dissection is performed at a distance of 5-9 mm from the limbus.

[0034] Miniature stents are held in the formed tube by means of puncture due to their self-expanding properties and are implanted by puncture with a puncture diameter smaller than the nominal diameter of the miniature stent.

[0035] The dosage of fluid flowing from the anterior chamber of the eye is ensured by contacting the proximal (outer) end of the micro-scaffold with the conjunctival tissue, thereby preventing rapid outflow of fluid.

[0036] When the method for which protection is required is used, it is not necessary to dissect the conjunctiva to form a cavity (filter bubble) beneath it, because the implantation of a mesh framework aligned with the boundaries of the anatomical structure allows fluid to flow out without forming a filter bubble.

[0037] Terms and Definitions

[0038] To better understand this invention, the following are some terms used in the specification of this invention. Unless otherwise specified, the technical and scientific terms in this application have the standard meanings generally accepted in scientific and technical literature.

[0039] In this specification and claims, the terms “comprising,” “containing,” “including,” “having,” “assembled,” and “containing,” and other grammatical forms, are not intended to be interpreted in an exclusive sense, but rather should be used in a non-exclusive sense (i.e., the meaning of “comprising”). Only expressions such as “consisting of” should be considered as an exhaustive list.

[0040] The term "stent" refers to a medical implant inserted into a blood vessel or tissue to maintain a lumen for fluid movement. For example, it can be a mesh frame made of metal or polymer, and stents can be cut from the corresponding tube, for example by laser cutting, or they can be braided. Stent materials are conventional, with self-expanding stents using shape memory materials such as nitinol, and balloon-expandable stents made of medical steel or cobalt-chromium alloys.

[0041] The term "micro-stent" refers to a stent that is significantly smaller than the most common stents used in clinical practice, such as coronary stents, which typically have a minimum diameter of 2 mm and a minimum length of 8 mm.

[0042] The term "cell" describes an opening present in the grid frame of a support structure. Overlapping cells represent facing openings on opposite sides of the support structure's perimeter.

[0043] The term "connection" refers to an operative connection that can be made using any number or combination of intermediate elements between the connected components (including without the use of intermediate elements).

[0044] Furthermore, the terms “first,” “second,” and “third,” etc., are used only as condition markers and do not impose any numerical or other restrictions on the listed objects. Attached Figure Description

[0045] The objects, features, and advantages of the present invention will become more apparent from the following description and accompanying drawings, which are described below:

[0046] Figure 1 This illustrates a miniature scaffold (a device for minimally invasive eye surgery) implanted in eye tissue.

[0047] Figure 2 AC illustrates the flowchart and working principle of a miniature stent delivery system (a device for minimally invasive eye surgery).

[0048] Figure 3 An embodiment of a miniature support delivery system with a handle is shown.

[0049] Figure 4 AE illustrates the steps involved in implanting a micro-scaffold (a device used for minimally invasive eye surgery). Detailed Implementation

[0050] The following description of exemplary embodiments of the invention is provided by way of example only and is intended for illustrative purposes and not to limit the scope of the disclosed invention.

[0051] The present invention relates to a drainage implantable device (micro-scaffold) and its implantation method during minimally invasive surgery, thereby forming a channel for the outflow of aqueous humor from the anterior chamber of the eye. Figure 1 An implantable microscaffold (50) according to the present invention is shown. The structural markings of the eye (10) are as follows: 102 – conjunctiva, 103 – trabecular meshwork, 104 – anterior chamber, 105 – sclera, 106 – limbus, 107 – anterior chamber angle, 101 – subconjunctival space.

[0052] The minimally invasive glaucoma surgical device (hereinafter referred to as the microscaffold) is a drainage tube (50) in the form of a hollow, self-expanding, full-length tubular frame. It is implanted from the outside of the eye (10) into the anterior chamber (104) of the eye through a puncture in the scleral corneal tissue (limbal area). The drainage tube (50) has a proximal end (51) and a distal end (52).

[0053] The implantation steps are as follows: Figure 4 As shown in A–E. Therefore, the microscaffold (50) is positioned such that its distal (inner) end (52) lies on the horizontal plane of the trabecular meshwork (103) without protruding into the anterior chamber (104), and its proximal (outer) end (51) lies on the horizontal plane of the boundary between the sclera (105) and the subconjunctival space (101) without protruding below the conjunctiva (102). This position of the microscaffold (50) is achieved through its geometry, which, under the influence of a pressure gradient, creates a channel for regulating the outflow of aqueous humor from the anterior chamber (104) to the subconjunctival space (101). The proximal (outer) end (51) of the microscaffold (50) contacts the conjunctival tissue (102), preventing rapid outflow of fluid.

[0054] Micro-scaffolds are made of nitinol (TiTi) or other shape memory materials through laser cutting or weaving, and are constructed using methods such as... Figure 2 , 3 The delivery system shown delivers the microscaffold to the implantation site, where it is compressed. Due to its self-expanding properties, the microscaffold forms a channel with a diameter larger than the puncture diameter. The pressure exerted by the microscaffold on the adjacent sclera-cornea tissue can fix the microscaffold (50) in the ocular tissue, a fixation that would not be possible if the geometry of the product remained unchanged during and after implantation.

[0055] To minimize the impact of the implant (microscaffold) on the body, contact between the implant and body tissues must be minimized. For this purpose, one end of the microscaffold, especially the proximal end (51), is angled. The proximal angle is selected based on the level of the proximal end (51) on the outer surface of the sclera. The length of the drainage tube should be proportionate to the thickness of the sclera-cornea tissue measured from the level of the apex of the anterior chamber angle (107) of the eye.

[0056] Each patient requires a micro-stent selected based on their individual needs. From a range of sizes with different lengths, nominal diameters, and bevel angles, a micro-stent with the optimal length, diameter, and bevel angle is selected for the specific patient and pre-loaded onto the delivery system while being sterilized. Size ranges may include micro-stents with lengths from 1.0 mm to 3.0 mm, nominal diameters (in the open state) from 0.5 mm to 1.5 mm, and proximal micro-stent bevel angles of 45° ± 15°.

[0057] To reduce potential inflammatory responses and cell proliferation, which could narrow the drainage channels, the microscaffold is coated at least along a portion (or the entire length) with a drug such as mitomycin C, 5-fluorouracil, sirolimus (rapamycin), probucol, dexamethasone, an anti-vascular endothelial growth factor agent, or a combination of these drugs. It may be polymer-free or mixed with biodegradable polymers (such as polylactic acid (polylactide), polylactic acid-glycolic acid copolymer, polylactic acid-caprolactone copolymer) or non-biodegradable polymers (such as biocompatible fluoropolymers).

[0058] According to the present invention, the frame of the microscaffold is mesh-like. In some non-limiting embodiments, the frame is a mesh with diamond-shaped, slit-shaped, or irregularly shaped openings.

[0059] Another aspect of the invention is a minimally invasive surgical kit comprising a micro-stent (50) having a specific length, a selected nominal diameter, and a proximal bevel angle, and a delivery system for the micro-stent (see...). Figure 2 ).

[0060] The micro-stent delivery system includes a sheath (201) to prevent expansion of the micro-stent (50) and a stop guide (202) located within the sheath to prevent longitudinal movement of the micro-stent within the sheath. The sheath (201) is designed as a cylindrical hollow body and has a distal end (2011). The stop guide (202) can be made with a variable cross-section or a constant cross-section. In the case of using a variable cross-section stop guide, the narrow portion of the stop guide is located within the micro-stent, and the wide portion of the stop guide prevents longitudinal displacement of the micro-stent within the sheath during implantation. In embodiments with a constant cross-section stop guide, the portion of the stop guide within the micro-stent is absent. Furthermore, the portion of the stop guide that contacts the proximal end of the bevel of the micro-stent has an angle, such that it makes close contact with the bevel end of the micro-stent in a compressed state. Figure 2 A schematic diagram of an embodiment of the delivery system is shown, wherein a stop guide (202) has a variable cross-section, and the narrow portion (2021) of the stop guide is located within a micro-support (50). The wide portion (2022) of the guide, which contacts the proximal end of the micro-support, is inclined.

[0061] Figure 3 A conveying system of one embodiment is shown in more detail. It should be noted that this conveying system is for demonstration purposes only, and the structure, form, and mechanism of operation of the conveying system may vary.

[0062] The miniature stent delivery system may include a handle (301) with a housing, the outer surface of which includes a control element (302) for adjusting the position of a stop guide (202) disposed within a sheath (201). In this case, the handle (301) may be part of a minimally invasive glaucoma surgery kit and may be part of a delivery system provided in a sterile state or connected to a sterile delivery system immediately prior to implantation.

[0063] The actuator (302) can be designed as a slider or roller, connected directly or via a reducer to the sheath (201) of the conveying system.

[0064] The device and its implantation method achieve stable reduction of intraocular pressure due to the following fundamental technical features:

[0065] • Self-expanding microscaffold structures made of nitinol or other shape memory materials.

[0066] • The miniature scaffold is short in length, and its thickness is proportional to the thickness of the sclera-cornea tissue at the level of the anterior chamber angle of the eye.

[0067] • The proximal end of the micro-stent is angled to ensure that the proximal end of the micro-stent is flush with the outer surface of the sclera.

[0068] • Minimize the contact area with eye tissues to improve the device's biocompatibility.

[0069] • Compared to existing devices, the lumen (inner diameter) is wider, thus solving the problem of pigment particles clogging the proximal and distal ends.

[0070] The delivery system has a stop guide that can slide longitudinally within the sheath, in which the micro-support is compressed and then unfolds in the ocular tissue due to its elastic properties.

[0071] • External implantation method.

[0072] The implantation of the miniature scaffold (50) involves several steps, from outside the eye (10) to inside, and from the conjunctiva (102) to the anterior chamber (104). Compared to the medial approach (passing through the anterior chamber from the opposite side), the lateral approach reduces surgical complexity and causes less damage to the eye. The steps for implanting the miniature scaffold (50) are as follows: Figure 4 As shown in AE.

[0073] During the procedure, diagnostic imaging techniques, endoscopy, or direct visual inspection are used to determine the appropriate placement of the mini-stent. During the examination, the most suitable standard size mini-stent is selected based on the patient's individual anatomy and pre-loaded onto the delivery system. Mini-stent dimensions may vary in length, diameter, and proximal bevel angle. The mini-stent is pre-loaded onto the delivery system during manufacturing and sterilized as a single kit for single use.

[0074] In one embodiment, the sterile disposable kit may also include a handle (301). In another embodiment, the handle serves multiple purposes and is connected to the delivery system immediately before surgery.

[0075] Next, use ophthalmic scissors, ophthalmic scalpels, or other ophthalmic instruments (see...) Figure 4 The location of this type of instrument is marked in the figure (401). A micro-incision (403) is made on the conjunctiva (102) 5-9 mm from the limbus (106), and then the sclera-corneal tissue is punctured (404) to reach the anterior chamber angle of the eye (104) (see Figure 4 A).

[0076] During the examination, a micro-scaffold (50) of selected size is encapsulated in the sheath (201) of the delivery system and pierced through the sclera and corneal tissue of the eyeball via a puncture (404) until the distal end (2011) of the delivery system sheath reaches the level of the anterior chamber angle (107) of the eye. Figure 4 C). The stop guide (202) is then secured in place, and the sheath (201) is slid along the proximal (posterior) direction to release the micro-stent (50) and allow it to expand to the nominal diameter. The micro-stent is secured in the limbal region of the eye by expanding to a diameter larger than the puncture diameter. After the micro-stent has been fully released from the sheath, the delivery system is removed.

[0077] The operation of moving micro-stents is usually performed under visual control (gonioscopy), taking all measures to ensure that its distal end does not protrude into the anterior chamber of the eye and that its proximal end is at the level of the cornea and does not protrude under the conjunctiva.

[0078] Once expanded, the miniature stent physically prevents the formed tube wall from closing, keeping it open. Therefore, a miniature stent can be inserted through a small opening while maintaining the patency of a larger diameter cavity or channel. The target pressure value provided by the miniature stent should be between 10 mmHg and 20 mmHg.

[0079] Because the implantation process of microporous stents is simple and minimally invasive, it can be used by ophthalmologists of any qualification. Since microporous stent implantation does not require patients to undergo long preoperative preparation, does not require sutures, and has almost no contraindications related to complications, it can be used for patients in the early stages of glaucoma, those with low compliance (patient adherence to treatment), and those who are intolerant to medications (eye drops).

[0080] Although this patent application relates to the invention as defined in the appended claims, it must be noted that this patent application contains the basis for formulating other inventions, for example, which may be claimed as the subject matter of the detailed claims of this application or as the subject matter of the claims of a separate and / or continuation application. Such subject matter may be characterized by any feature or combination of features described herein.

Claims

1. A device for minimally invasive glaucoma surgery, characterized in that, The device is a self-expanding frame-type drainage tube with distal and proximal bevels. The device is designed to be implanted from the outside of the eye inward, from the conjunctiva to the anterior chamber of the eye. Through puncture in the scleral-corneal tissue at the level of the anterior chamber, the distal end of the drainage tube is positioned at the level of the trabecular meshwork, and the proximal end is positioned at the boundary of the space between the sclera and subconjunctiva, without protruding beneath the conjunctiva. The frame self-expands along its entire length after implantation.

2. The apparatus according to claim 1, characterized in that, The angle of the proximal end of the drainage tube is selected based on the horizontal position of the proximal end on the outer surface of the sclera.

3. The apparatus according to claim 2, characterized in that, The oblique angle is in the range of 30° to 60°.

4. The apparatus according to claim 2, characterized in that, The oblique angle is 45°.

5. The apparatus according to claim 1, characterized in that, The length of the drainage tube is proportional to the thickness of the sclera-cornea tissue measured from the level of the apex of the anterior chamber angle of the eye.

6. The apparatus according to claim 5, characterized in that, The length of the drainage tube is in the range of 1.0 mm to 3.0 mm.

7. The apparatus according to claim 1, characterized in that, The diameter of the frame in the open state is constant and ranges from 0.5 mm to 1.5 mm.

8. The apparatus according to claim 1, characterized in that, The frame is composed of shape memory material.

9. The apparatus according to claim 1, characterized in that, The framework is composed of nickel-titanium.

10. The apparatus according to claim 1, characterized in that, At least a portion of the outer surface of the drainage tube is coated with at least one antiproliferative drug selected from the group consisting of mitomycin-C, 5-fluorouracil, sirolimus (rapamycin), probucol, dexamethasone, and antivascular endothelial growth factor agents.

11. The apparatus according to claim 1, characterized in that, At least a portion of the outer surface length of the drainage tube is coated with a mixture of an antiproliferative drug and a polymer, wherein the drug is selected from the group consisting of: mitomycin C, 5-fluorouracil, sirolimus (rapamycin), probucol, dexamethasone, and antivascular endothelial growth factor agents, and the polymer is a biodegradable polymer selected from the group consisting of: polylactic acid (polylactide), polylactic acid-glycolic acid copolymer, polylactic acid-caprolactone copolymer, or a durable polymer, such as a biocompatible fluoropolymer.

12. The apparatus according to claim 1, characterized in that, The framework is a mesh.

13. A kit for minimally invasive glaucoma surgery, characterized in that, The device includes any one of claims 1 to 12, and a preloaded delivery system comprising a tubular sheath and a stop guide, the sheath being designed to contain the device in a compressed state within the sheath, guide the device to the implantation site and prevent the device from expanding, and the stop guide being located within the sheath, capable of sliding longitudinally relative to the sheath and abutting against the proximal end of the device and preventing longitudinal movement of the device within the sheath.

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