MXPA00006744A - Anterior chamber implant for treating the phakic eye - Google Patents

Abstract

The invention concerns an anterior chamber implant for treating the phakic eye comprising an optical part (1) connected to loops (3, 4). Viewed in profile each loop has an arc-shaped profile with double radius of curvature, the radius of curvature (R1) of the proximal part being greater than that (R2) of the distal part.

Description

IMPLANT OF THE PREVIOUS CHAMBER FOR THE TREATMENT OF THE FAQUITIOUS EYE DESCRIPTION OF THE INVENTION The present invention relates to an ocular implant in the anterior chamber for treating facitic eye conditions, in particular myopia, astigmatism and hyperopia. Such an implant consists, in a known manner, of an optical part (lens), generally of the circular contour and with an appropriate section for the planned correction (flat, planoconvex, biconvex, planoconcave, biconcave, meniscus, toric); connected to this optical part there is a haptic part which is intended to fix the position of the optical part in the anterior chamber. The haptic part consists of fine and deformable loops that, in use, are housed in the iridocorneal angle. An implant of the above type, intended for the correction of myopia, is diagrammatically shown in Figures 1, 2 and 5 appended with the present disclosure, Figure 1 being a plan view, Figure 2 is a side view, and Figure 5 a REF.121427 diagrammatic view of the implant according to Figures 1 and 2 in position in an eye. Figure 1 shows the optical part 1, the zone 2 connection between this optical part and the two loops 3 and 4 that have the general shape of an S, the distal part of each loop has two feet 5 and 6 of support. Note in Figure 2 that the optical part 1 is of the concave type and that the loops 3, 4 are angled from their proximal part for connection with the optical part 1 towards their distal support part, relative to a plane A of vertical support. This angle a is of the order of 15 ° and is intended to ensure that the optical part 1 is placed in the anterior chamber of the eye without risk of contact either with the cornea on its front face or with the iris on its back face. It will also be noted in Figure 2 that the distal end of the loops 3 and 4 coincide with the vertical plane A along a relatively large length. The implant has a width of about 5.5 mm (reference L in Figure 1) and is recorded on a covered curve having a diameter between 12 mm and 13.5 mm (reference D in Figure 1). Such an implant is adapted in most forms and sizes of eyes found in patients recovering from refractive surgery. However, with the previous models, irritation was found in a not insignificant number of cases due to the fact that the distal part of the loops leads to the periphery of the iris. The object of the present invention is to overcome this disadvantage by greatly reducing the risk of this distal part of the loops leading to the periphery of the iris, without taking into account the size of the eye to which it was implanted. According to the invention, each loop, seen in profile, has a profile formed in arc with double radius of curvature to place the driven surface in the iridocorneal angle. The invention will be better understood with the aid of the following description of a non-limiting embodiment, with reference to Figures 3, 4 and 6. Figure 3 is a diagrammatic plan view of an implant to myopia in the anterior chamber in accordance with the invention Figure 4 is a diagrammatic side view of the implant shown in Figure 3.

And Figure 6 is a diagrammatic view of the implant according to Figures 3 and 4 in position in the eye. The references for the parts corresponding to those implants illustrated in Figures 1 and 2 are identical. There is an optical part 1, a peripheral connection part 2 and two loops 3 and 4 in the general form of an S (plan view), of which the distal part has a support foot 5 and 6. Each of the loops has, in side view according to Figure 4, a profile formed in an arc with double curvature. The radius of curvature (Rl) of the proximal part is greater than that of the distal part (R2). The point of passage from one radius of curvature to the other is located (cf. reference P in Figure 4) at a distance from the distal end of the loop in question, approximately equal to a quarter of the height of the loop, in a parallel direction to the support plane A. The formation of general angles of the loop relative to the support plane A is between 13.5 ° and 16 ° and is preferably 15.12 ° (angle a in Figure 4) for an implant with a 12.5 mm covered curve.

The value of the radius of curvature is between 10 and 35 mm for the proximal part (Rl) and 2.5 mm for the distal part (R2). With these configurations, the head of the loop (reference F in Figure 4) will be placed approximately 1 mm from the support plane A, and the point of the optical part closest to the cornea will be placed at 1.62 mm (reference c in the Figure 6). This guarantees that the deformations of the loops, secondary to those of the eyeball, do not cause risk to the contact of the implant with the cornea or with the iris. The bow shape with double radius of curvature ensures that the loops will only lead over the relatively strong structures of the iridocorneal angle (scleral spur, trabecula). More precisely, according to Figure 6, and in contrast to Figure 5: the proximal part of each loop, with large radii of curvature (Rl), is almost parallel to the optical plane; it is located as far as possible from the iris, to allow pupillary movement without contact between the loop and the iris; the distal part of each loop, with small radii of curvature (R2), attached to the proximal part practically at the site of implantation of the loops, which corresponds to the angle of the anterior chamber; • - each loop is thus placed in a middle position between the iris 10 and the corneal endothelium 11; the support surface of each loop in the iridocorneal angle remains limited; almost all contact between the distal part of each loop and the iris is prevented, thereby limiting any inflammatory reaction of the latter. An embodiment of an implant in the above has been described in which the haptic part comprises two loops, but it functions without saying that the present invention is applicable for any anterior chamber implant to treat the fachitic eye, without taking into account the number of ties of his haptic part. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects or products to which it refers.

Claims (5)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. An implant of the anterior chamber for treating the fachitic eye, comprising an optical part connected to loops, characterized in that, seen in profile, each loop has an arc-shaped profile with a double radius of curvature, the radius of curvature being (Rl) ) of the proximal part greater than that (R2) of the distal part.

2. The implant according to claim 1, characterized in that the point of passage between the two radii of curvature (Rl) and (R2) are located at a distance from the distal end of the loop approximately equal to a quarter of the height of the loop in a direction parallel to the vertical plane A.

3. The implant according to claim 1 or 2, characterized in that the formation of general angles () of a loop is between 13.5 ° and 16 ° relative to the support plane (A).

4. The implant according to claim 3, characterized in that the angle formation of a loop is 15.12 ° for an implant with a covered curve of 12.5 mm.

5. The implant according to any of claims 1 to 4, characterized in that the value of the radius of curvature is: Rl: > 10mm < _ 35 mm R2: 2.5 mm IMPLANT OF THE PREVIOUS CHAMBER FOR THE TREATMENT OF THE FAQUITIC EYE SUMMARY OF THE INVENTION The invention relates to an anterior chamber implant for treating the fachitoid eye comprising an optical part (1) connected to loops (3,4). Seen in profile, each loop has an arc-shaped profile with a double radius of curvature, the radius of curvature (Rl) of the proximal part being greater than that (R2) of the distal part.