Bifocal implant and method for altering the refractive properties of the eye
The present invention relates to an implant for insertion between layers of the cornea. The Implant includes a first portion adapted to change the curvature of the cornea at first area and thereby alter the refractive properties of the cornea at the first area, and a second portion adapted to change the refractive properties of a second area of the eye adjacent the first area and compensate for error at the second area caused by the first area change in curvature.
1 . A method of altering the refractive properties in an eye, comprising the steps of
separating layers of the cornea to form a first corneal layer and a second corneal layer, the first corneal layer facing in a posterior direction and the second corneal layer facing in an anterior direction,
inserting an implant between the first corneal layer and the second corneal layer, said implant including a first portion and a second portion, said first portion adapted to alter the refractive properties of the eye and the said second portion adapted to correct error, including error caused by said first portion.
2 . A method according to claim 1 , wherein
said first portion is at the periphery of the implant.
3 . A method according to claim 2 , wherein
said second portion as at the center of the implant and is substantially surrounded by said first portion.
4 . A method according to claim 1 , wherein
said first portion is configured to correct presbyopia and said second portion is configured to correct at least one of myopia and hyperopia.
5 . A method according to claim 1 , wherein
said second portion is configured to correct presbyopia and said first portion is configured to correct at least one of myopia and hyperopia.
6 . A method according to claim 1 , wherein
said step of separating layers of the cornea includes separating layers of the cornea to form a flap attached to the cornea at a peripheral portion thereof.
7 . An implant adapted to be positioned between a first surface of the cornea and a second surface of the cornea for altering refractive properties of an eye, comprising:
a first portion adapted to alter the refractive properties of a predetermined first area of the eye by displacing the first surface of the cornea at said first predetermined area, thereby changing the curvature of the cornea at said first predetermined area; and
a second portion adapted to alter the refractive properties of a predetermined second area of the eye adjacent said first predetermined area, said second portion further adapted to compensate for error at said predetermined second area caused by said first portion.
8 . A method according to claim 7 , wherein said first portion is at the periphery of the implant.
9 . A method according to claim 8 , wherein
said second portion as at the center of the implant and is substantially surrounded by said first portion.
10 . A method according to claim 9 , wherein
said first portion is configured to correct presbyopia and said second portion is configured to correct at least one of myopia and hyperopia.
11 . A method according to claim 9 , wherein
said second portion is configured to correct presbyopia and said first portion is configured to correct at least one of myopia and hyperopia.
12 . An implant for insertion between layers of the cornea, comprising:
a first portion adapted to change the curvature of the cornea at first area and thereby alter the refractive properties of the cornea at said first area; and
a second portion adapted to change the refractive properties of a second area of the eye adjacent the first area and compensate for error at said second area caused by said first area change in curvature.
13 . An implant according to claim 12 , wherein
said implant is substantially circular and said first portion is substantially ring-shaped and at the periphery of said implant.
14 . An implant according to claim 12 , wherein
said second portion is substantially at the center of said implant and surrounded by said first portion.
15 . An implant according to claim 14 , wherein
said second portion is configured to correct presbyopia.
16 . An implant according to claim 15 , wherein
said first portion is configured to correct at least one of myopia and hyperopia
17 . An implant according to claim 14 , wherein
said first portion is configured to presbyopia.
18 . An implant according to claim 17 , wherein
said second portion is configured to correct at least one of myopia and hyperopia.
19 . An implant according to claim 17 , wherein
said second portion is configured to return the refractive properties of the second area to its original emmetropic condition.
20 . An implant according to claim 14 , wherein
said implant is sized and configured to be substantially centered about the main optical axis of the eye.
21 . A method of forming a multifocal implant for insertion between layers of a cornea of an eye, the implant configured to change the refractive properties of the eye, the method comprising the steps of
determining a first refractive error of a first condition in the eye,
forming a first portion of the implant such that the first portion is configured to alter the corneal curvature at a first predetermined area of the eye and thus correct the first refractive error at the first predetermined area,
determining a refractive error caused by the first portion altering the corneal curvature at a second predetermined area of the eye, and
forming a second portion of the implant such that the second portion of the implant is configured to alter the corneal curvature at the second predetermined area and thus correct the refractive error caused by the first portion.
22 . A method of forming a multifocal implant according to claim 21 , further comprising the steps of
determining a second refractive error of a second condition in the eye, and
forming the second portion of the implant such that the implant is configured to alter the corneal curvature of the second predetermined area to thus correct a combined refractive error caused by the first portion and the second condition.