FR2690331A1 - Intra=ocular lens implant with radiating haptic arms - has central lens portion, with two diametrically-opposed strands configured as double arcs, outer arc not being centred on centre of lens - Google Patents

Abstract

Posterior chamber intraocular implant (1) comprising: - an optical part (2) - and a haptic part (4) comprising two diametrically opposed handles (5, 6), each comprising a connecting segment (5a, 6a), with a path gradually moving away from the optical part, and a support segment (5b, 6b) of circular profile, and with a path in a different direction from that of the connecting segment, characterized in that the support segment (5b, 6b) has a profile substantially in an arc of a circle centered on a point (60) different from the center (7) of the optical part, located in the anterior quadrant (8) delimited by a first diameter passing through the two points (5d, 6d ) connecting the two handles (5, 6) respectively with the optical part (2), and a second diameter perpendicular to the first diameter, said anterior quadrant being located immediately before the so-called reference quadrant (9) containing the segment (6a) of attachment.

Description

INTRAOCULAR IMPLANT OF POSTERIOR CHAMBER
The present invention relates to an intraocular implant, intended to replace, by surgical placement in the posterior chamber, the cataract lens of the eye, previously eliminated and extracted by phacoemulsification.

 This implant can be placed behind the iris, either in ciliary support or in capsular support, that is to say in the capsular bag.

A posterior chamber implant is already known comprising - an optical part comprising a lens adapted to the
restitution of the patient's vision, after extraction of the
crystalline; this lens can be mono-focal or
multi-focal, bi-convex, bi-concave, concave / convex,
etc ...

- and a haptic part comprising two handles
diametrically opposite, each comprising a segment
connecting, progressively moving away
of the optical part, and of curvature turned towards this
last, and a profile support segment substantially
circular, and in a different direction to that of
connecting segment, from a retrograde zone
located at the end of said connecting segment,
opposite its point of connection with the optical part.

 The haptic part of such an implant is relatively flexible, and ensures its good support in the eye, once the implant is in place. But its manipulation is relatively difficult, through a small corneal incision, for example of the order of 5 mm, and as practiced by phacoemulsification.

 The present invention therefore relates to an implant of the aforementioned type, which can be handled much more easily by the surgeon, through small incisions, and this without harming the flexibility and proper positioning of the same implant.

 According to the present invention, and as demonstrated below, the handling of the implant is significantly improved by the following geometric characteristic.

 The support segment of each handle has a profile substantially in an arc, centered on a point different from the center of the optical part, located in the anterior quadrant delimited by a first diameter passing through the two connecting points of the two handles respectively with the optical part, and a second diameter perpendicular to the first diameter, said anterior quadrant being located immediately before the so-called reference quadrant, containing the connecting segment of the handle considered, according to the direction of rotation around the optical part, determined by the direction of the path of the connecting segment from said optical part.

The present invention is now described with reference to the accompanying drawings, in which - Figure 1 shows, seen from the front, an implant
intraocular according to the invention - Figure 2 shows a side view and in profile of
the implant represented in figure 1 - figure 3 represents the passage of an implant according to
the invention, through the capsular opening
previously provided by capsulotomy, under the effect of
manipulation of the surgeon.

An implant 1 according to the invention comprises - an optical part 2 comprising a lens 3, intended
to play the role of the previously extracted lens - and a haptic part 4 comprising two handles 5 and 6
diametrically opposite, extending respectively from
on either side of the optical part 2, and described
below.

 Each loop 5 or 6 comprises a segment 5a or 6a of attachment, of path progressively moving away from the optical part, from a point of connection 5d or 6d with the latter, to a retrograde zone 5c or 6c; each connecting segment has a curvature facing the optical part. After the aforementioned retrograde zone, each loop then comprises a segment 5b or 6b of support against the sulcus or the capsular wall, of substantially circular profile, and of travel in a direction different from that of the connecting segment preceding it; each support segment 5b or 6b extends from the retrograde zone 5c or 6c, located at the end of the attachment segment 5a or 6a, opposite its point of connection 5d or 6d with the optical part 2, up to 'at a free end 5th or 6th.

 According to the invention, each support segment 5b or 6b has a profile substantially in an arc, centered on a point 60 different or offset from the center 7 of the optical part 2. This point 60 is located in the quadrant front 8, delimited by a first diameter 12 passing through the two points 5d and 6d connecting the two handles 5 and 6 respectively with the optical part 2, and a second diameter 13 perpendicular to the first diameter, this anterior quadrant 8 being located immediately before the reference quadrant 9 containing the attachment segment 6a, with regard to the loop 6, according to the direction of rotation around the optical part 2, determined by the direction of the path of the attachment segment 6a from the optical part 2.

 The same geometric characteristics can be observed, but will not be described, with regard to the other loop 5 of the haptic part 2.

 As shown in Figure 2, the haptic part 4 is shaped, relative to the equatorial plane of the optical part 2, to project the latter behind the support plane 10 in the eye, determined by the two support segments 5b and 6b opposite.

 As shown in FIG. 1, the two directions of the two paths of the two attachment segments 5a and 6a respectively determine the same direction of rotation around the optical part 2.

 It will also be observed that each support segment 5b or 6b is entirely contained in the so-called reference quadrant, that is to say that containing the attachment segment of the handle considered. This means that the latter extends in the reference quadrant, from the retrograde zone 5c or 6c to the free end 5e or 6e.

 As discussed below, each retrograde zone 5c or 6c of each loop 5 or 6 determines a point of articulation 5f or 6f of the support segment 5b or 6b, relative to the attachment segment 5a or 6a. As shown in FIG. 1, each support segment 5b or 6b makes an angle relative to the circle 14 passing through the point of articulation 5f or 6f, between 5 and 150, and preferably equal to 110. This angle is determined by, on one side the tangent to the aforementioned circle, at the articulation point 5f or 6f, and on the other side by the straight line connecting, for a given support segment, the free end 5e or 6e and the point 5f or 6f.

 With regard to the value of the aforementioned angle, it has in fact been determined that for an angle a greater than 15, the support segment 5b or 6b is no longer in contact with the wall of the eye, in the vicinity of the retrograde zone 5c or 6c. And for a value of the angle a less than 5, each support segment 5b or 6b is no longer in contact with the wall of the eye, in the vicinity of the free end 5e or 6e.

 We will now explain below the different effects and advantages obtained thanks to the geometric characteristics described above, with regard to each handle 5 or 6.

 Each retrograde zone 5c or 6c creates an elbow in a location of each handle 5 or 6, intermediate between the optical part 2 and each support segment 5b and 6b. As shown in FIG. 3, during the placement of the implant 1 in the capsular bag, such an elbow 5c or 6c makes it possible to guide without effort the handle 5 or 6 which remains outside the capsular bag, to cross the upper capsular flap 16a, with a slight rotation of the implant, and place all of the latter in capsular support.

 Thanks to the invention, each support segment 5b or 6b is regularly centrifuged from the center 7 of the optical part 2. This makes it possible to ensure contact of this segment with the capsular bag, practically over its entire length, and this whatever the anatomical variations in the diameter of the capsular bag.

 As already said, each support segment 5b or 6b is articulated on the preceding attachment segment 5a or 6a, at a point of articulation 5c or 6c. This allows, when the implant is in position in the eye, to orient each support segment 5b or 6b, tangentially to the equator of the capsular bag.

 Furthermore, it should be observed that the solution according to the invention makes it possible both to ensure the greatest possible length of contact between each support segment 5b or 6b and the capsular bag, and to limit the force exerted on the wall of the latter, thanks to the flexibility in articulation provided to each said segment 5b or 6b.

 In total, and according to the invention, an implant is obtained which makes it possible to follow the shape of the capsular bag, without deforming it, and this with good stability and excellent centering in the eye.

Claims (5)

 1. Implant (1) intraocular posterior chamber, intended to replace in the capsular bag to the lens of the eye, comprising - an optical part (2) comprising a lens (3) - and a haptic part (4) including two handles (5.6)  diametrically opposite, each comprising a segment  (5a, 6a) connecting, moving away  gradually of the optical part, and of curvature  turned towards the latter, and a segment (5d, 6d)  circular profile support, and directional path  different from that of the connecting segment, from  a retrograde zone (5c, 6c) located at the end of said  connecting segment opposite its point of  connection (5d, 6d) with the optical part characterized in that the support segment (5b, 6b) has a profile substantially in an arc centered on a point (60) different from the center (7) of the optical part, located in the anterior quadrant (8) delimited by a first diameter passing through the two points (5d, 6d) connecting the two handles (5,6) respectively with the optical part (2), and a second diameter perpendicular to the first diameter , said anterior quadrant being located immediately before a so-called reference quadrant (9) containing the attachment segment (6a), according to the direction of rotation around the optical part (2), determined by the direction of travel of the attachment segment ( 6a) from said optical part.  2. Implant according to claim 1, characterized in that the haptic part (4) is shaped to project the optical part (2) behind the support plane (10) in the eye, determined by the two segments of support (5b, 6b).  3. Implant according to claim 1, characterized in that the two paths of the two attachment segments (5a, 6a) respectively determine the same direction of rotation around the optical part (2).  4. Implant according to claim 1, characterized in that each support segment (5b, 6b) is entirely contained in a reference quadrant.  5. Implant according to claim 1, characterized in that the bearing segment (5b, 6b) makes an angle relative to the circle centered on the center (7) of the optical part (2), and passing through the point d articulation of the retrograde zone (5c, 6c), between 5 and 150, and preferably equal to 110.