Extra-ocular implant used to prevent worsening of pathological myopia

Abstract

The invention relates to an extra-ocular implant (1) used to prevent worsening of pathological myopia, the implant comprising a support structure (10) produced in the form of an arm having, at a first end, anchoring means and a second end comprising a concavity (120), the implant (1) being characterized in that it further comprises a pouch (13) in which a compound suitable for inflating the pouch (13) is arranged, the pouch (13) being positioned at the second end of the arm so as to occupy the concavity (120), the implant (1) further comprising an attachment device (130) arranged on the pouch (13) for positioning against the posterior portion of the eye.

Description

[0001] DD24582 LP

[0002] 1

[0003] Description

[0004] Title of the invention: Extraocular implant used for the prevention of the worsening of pathological myopia

[0005] Technical field of the invention

[0006] The invention relates to an extraocular implant used for the prevention of the worsening of pathological myopia.

[0007] State of the art

[0008] 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.

[0009] Furthermore, high myopia is characterized by axial elongation of the eye with a thinning of the sclera. It is important to distinguish between "classic" myopia (from 0 to -6D) and high myopia, where the refractive power of correction is less than -6D. The type of myopia can also be characterized 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, new blood vessels, macular holes), and retinal detachments. This is referred to as pathological myopia.

[0010] An ocular implant has already been described in patent application WO2017 / 033081 A1.

[0011] To prevent eye elongation, some authors propose a solution called posterior scleral reinforcement (PSR). The goal of this PSR is to slow down, or even stop, axial elongation at the macular level (the area most important for vision).

[0012] Different configurations have been proposed in the prior art, described in patent applications CN104523367, CN21937515A and CN108066054A.

[0013] These earlier documents are based on principles of indentation and fixation, not reinforcement. As a reminder, indentation involves passing a silicone band under the eye muscles to press on the sclera and bring it closer to the detached retina. These principles result in uneven pressure on the eye and often require a significant number of sutures, making the surgery complex.

[0014] Other solutions have been proposed in patent documents CN115414175A, CN213607387, CN203815706U and CN114306755A. DD24582 LP

[0015] 2

[0016] More specifically, the solution described in patent application CN108066054A does not provide for the presence of a special attachment device on the back of the eye, the pocket being held by simple mechanical pressure.

[0017] The aim of the invention is to propose an extraocular implant-type device for use in the treatment of high myopia, operating without indentation, i.e. without applying forces likely to deform the posterior pole of the eye, this device being simple to put in place and ultimately allowing to block the elongation of the eye at the level of the posterior sclera.

[0018] Description of the invention

[0019] 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 one 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, the hooking device comprising several prominent hooking elements on an inner face, this inner face being intended to come to rest against the posterior part of the eye.

[0020] One of its distinctive features is that the pocket is made of a transparent material.

[0021] Another distinctive feature is that the pouch is made of biocompatible silicone or elastomer.

[0022] According to another distinctive feature, the compound placed in the pocket is a biocompatible hardening compound.

[0023] According to another particularity, the hardening compound is chosen 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.

[0024] Another distinctive feature is that the reinforcement is made in the form of a rigid lattice structure.

[0025] Another distinctive feature is that the frame is made of a material chosen from among a biocompatible metal or one coated with a biocompatible layer, PMMA (Polymethyl Methacrylate), PSU (Polysulfone), PEEK (Polyetheretherketone), and PEKK (Polyetheretherketone). DD24582 LP

[0026] 3

[0027] According to another feature, the implant includes a filling channel connected to said pocket and attached to said rigid frame.

[0028] According to another feature, the implant includes at least one optical fiber with an entry located on the side of the first end of the rigid frame and extending through a free end through a sheath made in the frame to emerge opposite said pocket.

[0029] According to another distinctive feature, the prominent gripping elements of the gripping device are formed of suction cups or hairs made of biocompatible elastomer or biocompatible synthetic material.

[0030] According to another feature, the anchoring devices include one or more tabs, each equipped with at least one opening suitable for the passage of a stitch.

[0031] Brief description of the figures

[0032] Other features and advantages will appear in the detailed description that follows, in conjunction with the attached figures listed below:

[0033] Figure 1 represents the implant according to the invention, seen in perspective;

[0034] Figure 2 shows the implant according to the invention, seen in perspective and exploded view; Figure 3 shows the implant according to the invention, seen in section along a vertical longitudinal plane;

[0035] Figure 4 shows the implant according to the invention, seen in profile and installed on an eye;

[0036] Figure 5 shows the attachment device made on the inner face of the implant pocket;

[0037] Detailed description of at least one embodiment

[0038] In the following description, the terms "front" and "back", or "anterior" and "posterior" are to be understood by taking as a reference the direction of vision (V in Figure 4) of an eye following a horizontal direction.

[0039] With reference to Figure 1, Figure 2, and Figure 3, implant 1 primarily comprises a framework 10 made in a rigid form (see example of materials used below). By "rigid form," it is meant that the framework 10 is only capable of flexing with a small degree of freedom.

[0040] This armature 10 is made in the form of an arm. DD24582 LP

[0041] 4

[0042] This frame 10 is preferably made with a lattice structure, but could also have a solid structure. This lattice structure ensures good mechanical resistance while remaining lightweight and compact for patient comfort.

[0043] This armature 10 is made of a biocompatible material. Without limitation, it can be made of a biocompatible metal (e.g., titanium) or of a metal coated with a biocompatible plastic layer. It can also be made of a material such as polymethyl methacrylate (PMMA), polysulfone (PSU), or a PEEK (polyetheretherketone) or PEKK (polyetherketoneketone) type material.

[0044] 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.

[0045] The arm forming the frame 10 has a first end and a second end.

[0046] According to a 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 figure 4).

[0047] At its first end, the arm has anchoring means. These anchoring means have one or more tabs 1 1, each tab 1 1 having at least one orifice 1 10 adapted for the passage of a suture (not shown), for anchoring the frame 10 to the upper part of the eye O.

[0048] 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.

[0049] The thickness of the reinforcement 10 can vary along its length, with a thin thickness at its anchorage to minimize bulk (preferably 1 mm) and a thicker thickness at its end shape 12.

[0050] 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 DD24582 LP

[0051] 5 of the staphyloma by applying uniform pressure to the staphyloma and without indentation.

[0052] 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 to allow it to be filled with the curing compound. Without limitation, each of its two front and rear faces has a surface area 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.

[0053] Without limitation, the hardening compound is initially in the form of a liquid injected into pocket 13 when implant 1 is already in place. Implant 1 thus comprises a channel 15 advantageously mounted on the framework 10, accessible at one end, forming its inlet, to receive the hardening compound and opening at a second end, forming its outlet, directly into the internal volume of pocket 13.

[0054] This channel can be made from 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 appropriate 150 attachments. The channel opening is advantageously located in the middle of the implant to avoid causing discomfort to the patient.

[0055] The hardening compound is, for example, chosen from one of the compounds listed below:

[0056] - A thermosensitive hydrogel with a liquid-solid transition temperature around 20°C (for example, a hydrogel from the poloxamer family)

[0057] - 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.

[0058] A cyanoacrylate-type compound or something like medical glue.

[0059] A medical cement-type compound (polyphosphate-based). DD24582 LP

[0060] 6

[0061] One or more photo-crosslinkable polymers, possibly mixed (e.g., acrylates, PEGDA or gelatin methacrylate)

[0062] 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.

[0063] Generally, the hardening compound is chosen for its biocompatibility and its curing 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 ligated after 10 to 20 minutes, such as 15 minutes.

[0064] Once the bag is filled via channel 15, the channel is no longer needed. After filling, it can be ligated or closed with a plug, septum, or valve.

[0065] It is also necessary to provide a device 130 for attaching the pouch 13 to the posterior part of the eye O. This device has several prominent attachment elements 131 on its inner surface (Figure 5), this inner surface being the one intended to bear against the posterior part of the eye. The attachment elements 131 of the device 130 can be composed of several suction cups distributed on the face of the pouch 13 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 moist environment. The suction cups are distributed to apply to all or part of the staphyloma.

[0066] As an alternative to suction cups, it is also possible to provide 131 attachment elements composed of gecko-type hairs, made of silicone, TPU or other biocompatible elastomer.

[0067] As indicated above, for its placement, 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 input of the optical fiber, a light signal S is injected using a light source; this signal then passes through DD24582 LP

[0068] 7 propagates through the optical fiber 14 to the pocket (signal S shown in Figure 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.

[0069] The positioning of implant 1 is, for example, carried out in the following manner:

[0070] - After conjunctival dissection in the lower temporal quadrant, the subconjunctival space is exposed by opening the tenon in contact with the sclera.

[0071] The implant is slid towards the posterior pole, keeping it as close as possible to the sclera. To ensure precise macular positioning, a fiber optic cable is used to view the device trans-sclerally with the aid of a microscope and a contact lens.

[0072] 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.

[0073] 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.

[0074] The optical fiber, which was positioned behind the implant, is then removed. The conjunctiva is sutured with 8 / 0 Vicryl.

[0075] The intervention is estimated to last 30 minutes.

[0076] It should be noted that other architectural configurations for the implant are also possible:

[0077] - 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.

[0078] A telescopic system or one with a notched rod can be added to adjust the length of the frame 10.

[0079] An additional adhesion zone can be added at the anchor point to adjust the fixation of implant 1 before suturing.

[0080] - Each suction cup can be fitted with a protective cover, the covers being removed at the time of application.

[0081] As an alternative to the hardening compound, pocket 13 can be inflated with medical air. DD24582 LP

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[0083] 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.

[0084] 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

DD24582 LP 9 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, the hooking device comprising several prominent hooking elements on an inner face, this inner face being intended to come to rest against 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 crosslinked 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), PS11 (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 bag and secured to said rigid frame. DD24582 LP 10 9. Implant according to any one of claims 1 to 8, characterized in that it comprises at least one optical fiber (14) having an entry located on the side of the first end of the rigid frame and penetrating by a free end through a sleeve (140) made in the frame (10) to emerge opposite said pocket (13).

10. Implant according to any one of claims 1 to 9, characterized in that the prominent attachment elements are formed of 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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