Title of Invention

ACCOMMODATIVE INTRACAPSULAR IMPLANT

Abstract ABSTRACT ACCOMMODATIVE INTRACAPSULAR IMPLANT Accommodative intracapsular implant comprising a central optical part, and at least two haptic arms (3, 4), the free ends (5, 6) of which are formed to cooperate with portions of equatorial zones of a capsular bag, characterized in that the optical part is formed by two bodies, elastically deformable and joined together, one body being shaped as an envelope (1), having an interior volume (V) and an own shape, and the other body being shaped as a core (2), having a volume (V) and an own shape, the interior volume (V) of the envelope (1) being identical to the volume (V) of the core (2) or greater than the same, the envelope (1) having an external surface with a convex anterior face (la) which has, when the envelope (1) is empty, a first radius of curvature (Rl), and when the envelope (1) houses the core (2), a second radius of curvature (R2), being smaller than the first radius of curvature (Rl), wherein the own shape of the interior volume (V) of the envelope (1), when empty, and the own shape of the core (2) in a free state are such that, when the two bodies (1,2) are assembled, they are elastically deformed in an antagonistic way via antagonistic forces to adopt a common shape, in which the core (2) and the envelope (1) mutually act against their respective tendency to elastically recover their own form and the antagonistic forces are in balance, and wherein, by causing an alteration of the balance of the antagonistic forces by an external field of forces F, the shape of the optical part and thus the optical power thereof is modified. Figure 3
Full Text

The present invention relates to accommodative intracapsular implant. The replacement of the natural crystalline lens by an artificial crystalline lens (implant) is nowadays usually practised, in particular on subjects reached of cataract.
The surgery more practised consists in withdrawing the matter of the natural crystalline lens contained in the capsular bag while preserving the integrity of this bag (except to the central part of its anterior wall) which then remains the receptacle of the implant located therein to replace the withdrawn natural matter.
BACKGROUND OF THE INVENTION
Intraocular lens assembly is disclosed in W09106259. There are now many implants. Most of them allow about recovering a far vision without accommodation possibility for a near vision.
Natural accommodation has made the subject of many studies with the aim to understand the phenomena which are involved to try to transpose them to the implants. The role of the capsular bag in the accomodation is extremely significant, in particular as an element of transmission to the crystalline matter of the forces generated by the ciliary muscle in the one or the other of its relaxed or contracted states, to which the capsular bag is connected by the zonular fibers.
Most recent work to date on the accommodative intracapsular lenses showed that the capsular bag and the crystalline matter are provided with their own elasticity which give the natural crystalline lens a modifiable form depending on the balance of forces between the state of tension of the zonular fibers, the elasticity of the capsular bag and the elasticity of the crystalline matter.
The loss of the accommodative capacity seems to be the result of an alteration of the
module of elasticity of the ciystalline matter in the course of the time, which opposes
an increasingly large resistance to the __

force of the bag for finally solidifying in an invariable state (regarding the forces brought into play) close to its shape for the far vision. This is the phenomenon of presbyopia.
OBJECT OF THE INVENTION
One of the objects of the invention is to propose an accommodative intracapsular implant which reproduces the natural mechanisms brought into play at the time of the accommodation.
BRIEF DESCRIPTION OF THE INVENTION
To this end the invention relates to an accommodative implant including a central optical part and at least two haptic arms whose loose ends are formed to co-operate with portions of the equatorial zone of the capsular bag, characterized in that the optical part is formed by two bodies elastically deformable joined together, one shaped as an envelope and the other in the shape of core, said enveloppe having an external surface with a convex anterior face which has, when the envelope is empty, a first radius of curvature and when the core is housed in the envelope, a second radius of curvature different from* the first radius of curvature.
It is thus reproduced, in the optical part of the implant an elastic structure in which two fields of antagonistic forces reign which give to the structure a determined shape when the forces are balanced. A disturbance of this balance by the addition of external forces results in a change of the shape of the optical part, in particular of the curve of its anterior face and thus of its optical power. The external forces are the ones transmitted to said composite optical part by the haptic parts which are themselves subjected to the change of the shape of the equatorial zone of the capsular bag. The implant accomodates primarily by a shape change of the optical part (with also a displacement of this one along the optical axis of the eye) contrary to all the known

implants which accommodate only by displacement.
BRIEF DESCRIPTION OF THE DRAWINGS
Other characteristics of the invention will appear in the description given hereafter as an exemple of one embodiment.
It will be refered to the annexed drawings in which:
- figure 1 is a diametrical cross section of the envelope of the implant according to the invention,
- figure 2 is a diametrical cross section of the core of the implant according to the invention,
- figure 3 is a diametrical cross section of the implant according to the invention, the envelope housing the core,
- figure 4 is a diametrical cut of the implant in its configuration corresponding in an accomodated state,
- figures 5 and 6 illustrate an alternative embodiment of figures 1 and 2,
figure 7 is a partial top view of the implant according to the invention.
The implant includes two parts: an envelope 1 represented empty on figure 1 and a core 2 represented in its free state on figure 2. The envelope 1 forms a hull made of elastic material, provided with two radial arms 3 and 4 equipped with end soles 5 and 6. This is the haptic part of the implant which engages equatorial zones of the capsular bag of the eye which is not represented.
Interior volume V of hull 1 is identical to volume V of core 2. This core 2 is carried out in an elastomer material, therefore elastically deformable so that when introduced into hull 2 this latter is inflated by the core and the core is flattened by the hull, because the free shape of the core 2 is more convex than the shape of volume V of the hull. The final shape reached by the optical part of the implant (that constitutes volume V of the hull filled with the core 2) is represented on figure 3.

Interior volume of the hull may be slightly greater than the one of the core made of elastomeric material in as much as this volume in excess has no significative influence on the mutual action of the hull and the core when assembled. The location of the core into the hull is made by any appropriate means : injection through an equatorial slit of the hull, jonction of two half hulls around the core...
In this shape, the radius of curvature R2 of the anterior face la of hull 1 is different from this same radius Rl when the hull is empty. Here the R2 radius is smaller than the radius Rl. The shape reached on figure 3 is the result of the balance of two fields of antagonistic forces born from the elastic compression of core 2 by hull 1 and from elastic expansion of hull 1 by core 2.
By causing an alteration of this balance by an external field of forces F (see figure 4) one modifies the balance, therefore the shape, of the optical part of the implant, therefore the radius of curvature R3 of its anterior face la is modified. The optical power of the composite lens 1, 2 is thus modified.
In the case*of figure 4, the field of forces F results from the action of the bag capsulaire on soles 5 and 6 when the zonular fibers are relaxed and that, by natural elasticity, the bag contracts radially. This is the state of the implant for a near sight, the radius R3 being smaller than the radius R2 which corresponds to the shape of the lens for a far vision.
Of course the posterior face lb of hull 1 has its radius of curvature changing as a result of the modification of the balance of the forces. It is possible, for example, by means of using various thicknesses of the hull wall 1, to influence such or such deformation, anterior or posterior, or even such type of deformation (spherical, conical...) . Figure 7 shows slits 7 provided in the anterior wall of the hull 1 to illustrate means of

adjustment of the ability of this hull to become deformed.
On figures 5 and 6, the shown embodiment illustrates a hull 10 which, empty, has a volume V more convex than that of core 20 to be housed. This difference in shapes generates, like previously, fields of forces, the balance of which results in the intermediate shape of the core housed in the hull.
Core 2, 20 can be made of a non elastic colloidal material (gel) housed in an envelope or an elastic pocket which confers to him its shape and its capacity with being elastically deformed.





WE CLAIM :
1. Accommodative intracapsular implant comprising
a central optical part, and
at least two haptic arms (3, 4), the free ends (5, 6) of which are formed to cooperate with portions of equatorial zones of a capsular bag, characterized in that
the optical part is formed by two bodies, elastically deformable and joined together,
one body being shaped as an envelope (1), having an interior volume (V) and an own shape, and
the other body being shaped as a core (2), having a volume (V) and an own shape,
the interior volume (V) of the envelope (1) being identical to the volume (V) of the core (2) or greater than the same,
the envelope (1) having an external surface with a convex anterior face (la) which has,
when the envelope (1) is empty, a first radius of curvature (Rl), and
when the envelope (1) houses the core (2), a second radius of curvature (R2), being smaller than the first radius of curvature (Rl),
wherein the own shape of the interior volume (V) of the envelope (1), when empty, and the own shape of the core (2) in a free state are such that, when the two bodies (1, 2) are assembled, they are elastically deformed in an antagonistic way via antagonistic forces to adopt a common shape, in which the core (2) and the envelope (1) mutually act against their respective tendency to elastically recover their own form and the antagonistic forces are in balance, and

wherein, by causing an alteration of the balance of the antagonistic forces by an external field of forces F, the shape of the optical part and thus the optical power thereof is modified.
2. Implant as claimed in claim 1, wherein the interior volume (V) of the envelope
(1) is identical to the volume (V) of the core (2) but of own shape different from that
of the core (2), when the envelope (1) and the core (2) are in a free state.
3. Implant as claimed in claim 1, wherein the core (2) is made of a colloidal material housed in an elastic envelope which determines its own form.
4. Implant as claimed in claim 1, wherein the core (2) is made of an elastomeric material having its own shape.
5. Implant as claimed in claim 1, wherein the anterior wall of the envelope is
provided with at least one radial slit (7).


Documents:

1676-chenp-2004- abstract.pdf

1676-chenp-2004- claims duplicate.pdf

1676-chenp-2004- claims original.pdf

1676-chenp-2004- correspondence others.pdf

1676-chenp-2004- correspondence po.pdf

1676-chenp-2004- description complete duplicate.pdf

1676-chenp-2004- description complete original.pdf

1676-chenp-2004- drawings.pdf

1676-chenp-2004- form 1.pdf

1676-chenp-2004- form 19.pdf

1676-chenp-2004- form 26.pdf

1676-chenp-2004- form 3.pdf

1676-chenp-2004- form 5.pdf

1676-chenp-2004- pct.pdf


Patent Number 207641
Indian Patent Application Number 1676/CHENP/2004
PG Journal Number 27/2007
Publication Date 06-Jul-2007
Grant Date 19-Jun-2007
Date of Filing 29-Jul-2004
Name of Patentee HUMANOPTICS AG
Applicant Address SPARDORFER STRASSE 150, D-91054 ERLANGEN.
Inventors:
# Inventor's Name Inventor's Address
1 HANNA KHALIL RUE COGNACQ JAY, F-75007 PARIS.
PCT International Classification Number A 61 F 2/16
PCT International Application Number PCT/FR03/00320
PCT International Filing date 2003-02-03
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 02/01240 2002-02-01 France