Corneal implant and method of manufacture
Prosthetic implants designed to be implanted in the cornea for modifying the cornea curvature and altering the corneal refractive power for correcting myopia, and myopia with astigmatism, such implants formed of a micro-porous hydrogel material.
1. A corneal implant for correcting hyperopia, comprising:
(a) a body formed of an optically clear, biocompatible, material having an index of refraction in the range of 1.36 to 1.39;
(b) the body being solid and having an anterior surface and a posterior surface that bi-meniscus in shape and joining each other at the periphery of the lens; with the anterior and prosterior surfaces having different radii of curvature; and
(c) the thickness of the edge being less than about 15 micrometers;
wherein said body is configured to alter an outer surface of a cornea of an eye to correct refractive error of the eye when implanted in the cornea.
2. The implant of claim 1 , wherein the body is generally circular in shape.
3. The implant of claim 1 , wherein the body is of a size greater than the size of the pupil in normal or bright light.
4. The implant of claim 1 , wherein the body is about 4.5 mm in diameter.
5. The implant of claim 1 , wherein the center of the body is no greater than 50 micrometers thick.
6. The implant of claim 1 , wherein the biocompatible, material is a microporous hydrogel.
7. The implant of claim 6 , wherein the microporous hydrogel has a water content greater than 40% up to approximately 90%.
8. The implant of claim 6 , wherein the microporous hydrogel has passageways to permit nutrient and fluid transfer, said passageways being small enough to act as a barrier against tissue in growth.
9. The implant of claim 6 , wherein the microporous hydrogel is made from at least one hydrophilic monomer which is polymerized and cross-linked with at least one multi- or di-olefinic cross-linking agent.
10. A method of implanting a corneal implant for correcting hyoperia, comprising the steps of:
(a) cutting away a portion of the outer surface of a cornea of an eye;
(b) implanting a lens on the exposed surface of the cornea with a body formed of an optically clear, biocompatible, material having an index of refraction range of 1.36 to 1.39, the body being solid and having an anterior surface and a posterior surface that are bi-meniscus in shape and joining each other at the periphery of the lens, with the anterior and posterior surfaces having different radii of curvature, the thickness of the edge being less than about 15 micrometers; and
(c) replacing the portion of the cornea that was cut away;
wherein the outer surface of the cornea is altered to corrected refractive error of the eye.
11. The method of claim 10 , wherein the body is generally circular in shape.
12. The method of claim 10 , wherein the biocompatible, material is a microporous hydrogel.
13. The method of claim 12 , wherein the microporous hydrogel has a water content greater than 40% up to approximately 90%.
14. The method of claim 12 , wherein the microporous hydrogel has passageways to permit nutrient and fluid transfer, said passageways being small enough to act as a barrier against tissue in growth.
15. The method of claim 12 , wherein the microporous hydrogel is made from at least one hydrophilic monomer which is polymerized and cross-linked with at least one multi- or di-olefinic cross-linking agent.