Extraocular implant used to prevent the worsening of pathological myopia

Abstract

The invention relates to an extraocular implant (1) used for preventing the worsening of pathological myopia, said implant comprising a frame (10) in the form of an arm having anchoring means at one end and a concavity (120) at the other. The implant (1) is characterized in that it also comprises a pocket (13) in which a suitable compound is placed to inflate said pocket (13). The pocket (13) is positioned at the second end of the arm to occupy said concavity (120). The implant (1) also comprises a hooking device (130) arranged on said pocket (13) to be positioned on the posterior part of the eye. Figure to be published with the abbreviation: Figure 4

Description

Title of the invention: Extraocular implant used for the prevention of the worsening of pathological myopia. Technical field of the invention

[0001] The invention relates to an extraocular implant used for the prevention of the worsening of pathological myopia. State of the art

[0002] Myopia is a vision disorder whose anatomical cause is mainly due to an excessive lengthening of the eye, that is to say that the distance between the retina and the cornea tends to increase over time.

[0003] Furthermore, high myopia is characterized by axial elongation of the eye with thinning of the sclera. A distinction must be made between "classic" myopia (from 0 to -6D) and high myopia, where the refractive power of correction is less than -6D. It is also possible to characterize the type of myopia by measuring the axial length of the eye. High myopia is defined as an axial length greater than 26 mm. The most severe cases of high myopia are characterized by axial lengths greater than 30 mm, with the eye continuing to grow abnormally. This leads to significant changes in the fundus, including staphylomas (scleral deformation), macular damage (stretching and rupture of certain tissues, neovascularization, macular hole), or retinal detachments. This is then referred to as pathological myopia.

[0004] To prevent elongation of the eye, some authors propose a solution called posterior scleral reinforcement (PSR). The aim of this PSR is to slow down, or even stop, axial elongation at the macular level (the area most important for vision).

[0005] Different configurations have been proposed in the prior art, described in patent applications CN104523367, CN21937515A and CN108066054A.

[0006] These prior documents are based on principles of indentation and fixation, not reinforcement. As a reminder, indentation involves passing a silicone strip under the eye muscles to press on the sclera and bring it closer to the detached retina. These principles result in uneven pressure being applied to the eye and often require a large number of sutures, making the surgery complex.

[0007] Other solutions have been proposed in patent documents CN115414175A, CN213607387, CN203815706U and CN114306755A.

[0008] The object of the invention is to provide an extraocular implant-type device for use in the treatment of high myopia, operating without indentation, that is to say without applying forces likely to deform the posterior pole of the eye, this The device is simple to set up and ultimately allows the eye to be blocked at the level of the posterior sclera. Description of the invention

[0009] This goal is achieved by an extraocular implant used for the prevention of the aggravation of pathological myopia, said implant comprising a frame made in the form of an arm having at a first end anchoring means and a second end comprising a concavity, said implant also comprising a pocket in which is placed a compound adapted to inflate said pocket, said pocket being positioned at the second end of the arm to occupy said concavity, the implant also comprising a hooking device arranged on said pocket to come to be positioned on the posterior part of the eye.

[0010] According to one particular feature, the pocket is made of a transparent material.

[0011] According to another feature, the pouch is made of silicone or elastomer biocompatible.

[0012] According to another feature, the compound placed in the pocket is a biocompatible hardening compound.

[0013] According to another feature, the hardening compound is chosen from a hydrogel, a crosslinkable or photoreticable polymer, a medical or cyanoacrylate type adhesive, a medical cement and a synthetic or natural polymer alone or mixed.

[0014] According to another feature, the reinforcement is made in the form of a rigid lattice structure.

[0015] According to another feature, the reinforcement is made of a material chosen from among a biocompatible metal or coated with a biocompatible layer, PMMA (Polymethyl methacrylate), PSU (Polysulfone), PEEK (Polyetheretherketone) and PEKK (Polyetherketoneketone).

[0016] According to another feature, the implant includes a filling channel connected to said pocket and secured to said rigid frame.

[0017] According to another feature, the implant comprises at least one optical fiber having an entry located on the side of the first end of the rigid frame and penetrating by a free end through a sheath made in the frame to emerge opposite said pocket.

[0018] According to another feature, the attachment device comprises several suction cups or hairs made of biocompatible elastomer or biocompatible synthetic material.

[0019] According to another feature, the anchoring means comprise one or more tabs, each provided with at least one opening adapted for the passage of a suture. Brief description of the figures

[0020] Other features and advantages will become apparent in the detailed description that follows, in conjunction with the attached figures listed below: - Fig. 1 represents the implant according to the invention, seen in perspective; - Figure 2 represents the implant according to the invention, seen in perspective and in exploded; - Fig. 3 represents the implant according to the invention, seen in cross-section along a vertical longitudinal plane; - Fig. 4 represents the implant according to the invention, seen in profile and installed on an eye;

[0021] Detailed description of at least one embodiment

[0022] In the following description, the terms "front" and "back", or "anterior" and "posterior" are to be understood by taking as reference the direction of vision (V on the [Fig.4]) of an eye following a horizontal direction.

[0023] With reference to [Fig. 1], [Fig. 2], and [Fig. 3], the implant 1 mainly comprises a framework 10 made in a rigid form (see example of materials used below). By "rigid form," it is understood that the framework 10 is only capable of flexing with a small degree of freedom.

[0024] This armature 10 is made in the form of an arm.

[0025] This reinforcement 10 is preferably made with a lattice structure (called (also a "lattice" structure) but could have a solid structure. This lattice structure guarantees good mechanical resistance while remaining lightweight and compact for patient comfort.

[0026] This frame 10 is made of a biocompatible material. Without limitation, it may be made of a biocompatible metal (for example, titanium) or of a metal coated with a biocompatible plastic layer. It may also be made of a material such as, for example, polymethyl methacrylate (PMMA), polysulfone (PSU), or a PEEK (polyetheretherketone) or PEKK (polyetherketoneketone) type material.

[0027] It should be noted that it will be possible to have different armature templates and to choose the one that takes into account the axial length of the patient's eye and the location of the staphyloma.

[0028] The arm forming the frame 10 has a first end and a second end.

[0029] According to one particular feature, the arm is curved so as to be able to follow the geometry of the eye O and to be able to hook, by its first end, on the upper part of the eye O and to be able to position itself, by its second end, opposite the posterior part of the eye O (see [Fig.4]).

[0030] At its first end, the arm includes anchoring means. These anchoring means include one or more tabs 11, each tab 11 having at least one orifice 110 adapted for the passage of a suture (not shown), for anchoring the frame 10 to the upper part of the eye O.

[0031] At its second end, the arm terminates in a spoon or ladle shape 12 forming a concavity 120, intended to be located opposite the posterior part of the eye O.

[0032] The thickness of the reinforcement 10 can vary along its length, with a low thickness at the anchorage to minimize bulk (preferably 1 mm) and a greater thickness at its end shape 12.

[0033] According to the invention, the implant 1 also includes a transparent inflatable pouch 13 filled with a hardening compound, which fits into the concavity 120 of the frame and is intended to occupy and fill the space between the second end of the arm and the posterior part of the eye. This solution aims to physically block the growth of the staphyloma by applying uniform pressure to the staphyloma without indentation.

[0034] The pocket 13 is made of a transparent material to allow the diffusion of a light spectrum generated by an optical fiber 14 used temporarily to position the implant 1 (see below). This pocket 13 is in the form of a cushion preferably made of silicone or an elastomeric material. It is initially under vacuum or has a vent so that it can be filled with the hardening compound. Without limitation, each of its two front and rear faces has a surface area of ​​between 50 mm² and 150 mm², for example, 100 mm². This surface area must be chosen appropriately to optimize coverage of the staphyloma while avoiding pressure on the optic nerve.

[0035] By way of exception, the hardening compound is initially in the form of a liquid injected into the pocket 13 when the implant 1 is already in place. The implant 1 thus comprises a channel 15 advantageously mounted on the frame 10, accessible at a first end, forming its inlet, to receive the hardening compound and opening at a second end, forming its outlet, directly into the internal volume of the pocket 13.

[0036] This channel can be made of a flexible silicone tube (e.g., Sani-Tech from Saint-Gobain or Pharma80 from Dow Chemical – registered trademarks). The channel is secured to the framework using suitable attachments 150. The channel opening is advantageously located in the middle of the implant to avoid causing discomfort to the patient.

[0037] The hardening compound is, for example, chosen from one of the compounds listed below: - A thermosensitive hydrogel with a liquid-solid transition temperature around 20°C (for example, a hydrogel from the poloxamer family) - A natural polymer that can be physically crosslinked with divalent cations (e.g., alginates, pectins, etc.) or chemically crosslinked via a crosslinking agent (e.g., hyaluronic acid). To prevent clogging of the filling channel, the crosslinking agent can be pre-coated in the pouch during device manufacturing before the liquid polymer is injected. - A cyanoacrylate-type compound or something like medical glue. - A medical cement-type compound (based on polyphosphates). - One or more photo-crosslinkable polymers, possibly mixed (e.g., acrylates, PEGDA or methacrylate gelatin) - A synthetic polymer (e.g. polyethylene glycol or other ethoxylated polymers) or natural polymer (e.g. low melting point fatty acid ester) used alone or in mixtures, the hardening of which would be triggered by the cooling of the liquid after injection.

[0038] Generally, the hardening compound is chosen for its biocompatibility and its hardening time. This time should not be too short to allow the surgeon sufficient time to fill the pocket. For example, the compound should have a viscosity that allows the filling device to be removed and the canal to be ligated after a period of between 10 and 20 minutes, for example, 15 minutes.

[0039] Once the bag is filled via channel 15, the channel is no longer needed. After filling, it can be ligated or closed by a plug, a septum or a valve.

[0040] It is also necessary to provide an attachment device 130 for the pouch 13 against the posterior part of the eye O. This attachment device 130 may consist of a solution with several suction cups distributed on the face of the pouch 13 located opposite the posterior part of the eye O. Each suction cup, for example, has a diameter of less than a few hundred microns and is adapted to function in a humid environment. The suction cups are distributed to apply to all or part of the staphyloma.

[0041] As an alternative to suction cups, it is also possible to provide an attachment device composed of gecko-type hairs, made of silicone, TPU or other biocompatible elastomer.

[0042] As indicated above, for its insertion, the implant 1 temporarily uses an optical fiber 14. The frame is traversed by an internal sheath 140 opening at the concavity opposite the pocket 13. The optical fiber 14 is inserted into said sheath 140 and is removed after the procedure. At the entry of the optical fiber, A light signal S is injected using a light source, this signal propagating through the optical fiber 14 to the pocket (signal S shown in [Fig. 3]). As the pocket 13 is made of a transparent material, the surgeon can control the positioning of the implant 1 during the procedure by trans-illumination of the posterior part of the eye O.

[0043] The positioning of the implant 1 is, for example, carried out in the following manner: - After conjunctival dissection in the lower temporal quadrant, the subconjunctival space is exposed by opening the tenon in contact with the sclera. - The implant is slid towards the posterior pole, keeping it as close as possible to the sclera. To ensure proper positioning at the macular level, a fiber optic is used to view the device trans-sclerally with the aid of a microscope and a contact lens. - Once properly positioned, the implant is attached to the sclera anteriorly by sutures (2 to 4 Mersuture 5 / 0 sutures), approximately 3 to 6mm from the limbus, in the inferior temporal quadrant. - Once the implant is fixed, the pocket is filled with the hardening compound, preferably a thermosensitive hydrogel with a liquid-to-solid transition temperature of around 20°C (room temperature) and a hardening time of around 15 minutes. - The optical fiber that was positioned behind the implant is then removed. - The conjunctiva is sutured with Vicryl 8 / 0. - The intervention is estimated to last 30 minutes.

[0044] It should be noted that it is also possible to foresee other architectural configurations for the implant: - The frame 10 can be provided articulated at its first end by means of a hinge or a ball joint to facilitate fixing on the eye O. - A telescopic system or one with a notched rod can be added to adjust the length of the frame 10. - An additional adhesion zone can be added at the anchor point, to adjust the fixation of implant 1 before suturing. - Each suction cup can be fitted with a protective cover, the covers being removed at the time of application. - As a replacement for the hardening compound, pocket 13 can be inflated with medical air. It is possible to provide a solution for delivering medication (e.g., atropine) or stem cells to the staphyloma using the bag or a second reservoir. It is possible to manufacture part of the implant as a single unit made of a flexible and biocompatible material. This unit would incorporate the functions of the pocket and the attachment device (suction cups or other), and a rigid framework could be added to reinforce the entire structure. Other designs could also be considered.

Claims

Demands

1. Extraocular implant (1) used for the prevention of the aggravation of pathological myopia, said implant comprising a frame (10) made in the form of an arm having at a first end anchoring means and a second end comprising a concavity (120), said implant (1) being characterized in that it also comprises a pocket (13) in which is placed a compound adapted to inflate said pocket (13), said pocket (13) being positioned at the second end of the arm to occupy said concavity (120), the implant (1) also comprising a hooking device (130) arranged on said pocket (13) to come to be positioned on the posterior part of the eye.

2. Implant according to claim 1, characterized in that the pocket is made of a transparent material.

3. Implant according to claim 1 or 2, characterized in that the pocket (13) is made of biocompatible silicone or elastomer.

4. Implant according to any one of claims 1 to 3, characterized in that the compound placed in the pocket is a biocompatible hardening compound.

5. Implant according to claim 4, characterized in that the hardening compound is selected from a hydrogel, a crosslinkable or photocrosslinkable polymer, a medical or cyanoacrylate type adhesive, a medical cement and a synthetic or natural polymer alone or mixed.

6. Implant according to any one of claims 1 to 5, characterized in that the reinforcement (10) is made in the form of a rigid lattice structure.

7. Implant according to any one of claims 1 to 6, characterized in that the framework (10) is made of a material selected from a biocompatible metal or coated with a biocompatible layer, PMMA (Polymethyl methacrylate), PSU (Polysulfone), PEEK (Polyetheretherketone) and PEKK (Polyetherketoneketone).

8. Implant according to any one of claims 1 to 7, characterized in that it comprises a filling channel (15) connected to said pouch and attached to said rigid frame.

9. An implant according to any one of claims 1 to 8, characterized in that it comprises at least one optical fiber (14) having an input located on the side of the first end of the rigid frame and extending through a free end through a sleeve (140) made in the frame (10) to open opposite said pocket (13).

10. Implant according to any one of claims 1 to 9, characterized in that the attachment device comprises several suction cups or hairs made of biocompatible elastomer or biocompatible synthetic material.

11. Implant according to any one of claims 1 to 10, characterized in that the anchoring means comprise one or more tabs (11) each provided with at least one orifice (110) adapted for the passage of a stitch.

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