Method of improving adherence and centering of intra-corneal implants on corneal bed

• US 6,733,526 B2
• Filed: 04/25/2002
• Issued: 05/11/2004
• Est. Priority Date: 04/25/2002
• Status: Expired due to Term

• Current Assignee: Johnson & Johnson Surgical Vision, Inc. (Johnson & Johnson)
• Original Assignee: Advanced Medical Optics Incorporated (Johnson & Johnson)
• Inventors: Paul, Marlene L., Glick, Robert
• Primary Examiner(s): Willse, David H.
• Assistant Examiner(s): Matthews, William H.
• Application Number:
  US10/132,465
• Publication Number:
  US 20030204252A1
• Time in Patent Office: 747 Days
• Field of Search: 623/4.1, 623/5.11, 623/5.12, 623/5.16, 623/901, 623/920
• US Class Current: 623/5.11
• CPC Class Codes: A61F 2/0095 Packages or dispensers for prostheses or other implants for intraocular lenses A61F2/1691; for dental surgery A61C19/02
• CPC Class Codes: A61F 2/147 Implants to be inserted in the stroma for refractive correction, e.g. ring-like implants
• CPC Class Codes: A61L 2430/16 for reconstruction of eye parts, e.g. intraocular lens, cornea
• CPC Class Codes: A61L 27/50 Materials characterised by their function or physical properties , e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials

Abstract

A partially hydrated lens is provided for implantation into a cornea. The partially hydrated lens has a water content less than the water content of the cornea, resulting in an osmotic pressure differential between the lens and the cornea which improves adhesion between the lens and the corneal tissue. It also causes the lens to expand and flatten when implanted, and to [naturally center itself while flattening.] In the preferred embodiment of the invention, the lens is maintained in its partially hydrated state by storage in a hypertonic hydration medium.

Claims

1. An intra-corneal implant comprising:

a lens structured to be implanted in a cornea and comprising a hydrophilic polymeric material;

the lens having an initial state prior to implantation into the cornea wherein the lens is partially hydrated and is more steeply curved than a central portion of the cornea, the lens being structured to be further hydrated after implantation into the cornea to a final state in which the lens assumes a flatter shape than the lens in the partially hydrated state.

2. The intra-corneal implant according to claim 1, wherein the lens in the final state has a curvature closely conforming to a substantially uniformly curved central area of a corneal stroma.

3. The intra-corneal implant according to claim 1, wherein the lens in the partially hydrated state has a first imbibition pressure causing the lens to absorb water from the cornea when implanted therein, and the lens in the final hydrated state has a second imbibition pressure causing the lens to substantially cease absorbing water from the cornea.

4. The intra-corneal implant according to claim 1, wherein the partially hydrated lens comprises an amount of fluid selected to create an osmotic pressure relative to stromal fluids in the cornea when the partially hydrated lens is implanted in the stroma of the cornea, the osmotic pressure gradient causing enhanced adhesion of the lens to the stroma.

5. The intra-corneal implant according to claim 1, in combination with means for maintaining the lens in the partially hydrated state prior to implantation in a cornea.

6. The combination according to claim 5, wherein the means for maintaining the lens in the partially hydrated state comprises a hypertonic hydration medium.

7. A packaging arrangement comprising:

a vessel containing a hypertonic hydration medium; and

a lens stored in the hydration medium for implantation in a cornea, wherein the lens is formed of a hydrophilic polymeric material.

the hydration medium having a tonicity such that the lens is in an initial state in which the lens is partially hydrated and is more steeply curved than a central portion of the cornea, the lens being structured to be further hydrated after implantation into the cornea to a final state in which the lens substantially conforms to the curvature of the central portion.

8. The packaging arrangement according to claim 7, wherein the hydration medium comprises an aqueous carrier and a tonicity adjusting agent.

9. The packaging arrangement according to claim 8, wherein the tonicity adjusting agent is selected from the group consisting of sodium chloride, potassium chloride, sodium phosphate monobasic, sodium phosphate dibasic and combinations thereof.

10. The packaging arrangement according to claim 7, wherein the lens is stored in a partially hydrated state.

11. The packaging arrangement according to claim 10, wherein the lens is expandable from the partially hydrated state to the final hydrated state.

12. A method for treating refractive errors in the cornea of an eye, comprising:

of implanting a partially hydrated lens in a cornea, the lens being more steeply curved than a central portion of the cornea;

causing the lens to absorb water from the cornea so as to flatten the lens;

allowing the lens to self-center within the cornea.

13. The method according to claim 12, wherein the lens has an imbibition pressure that causes the lens to absorb water when implanted in the cornea.

14. The method according to claim 13, wherein the lens expands to an equilibrium state as it absorbs water from the cornea, the lens substantially ceasing to absorb water when in the equilibrium state.

15. The method according to claim 14, wherein:

the lens in the equilibrium state has a curvature closely conforming to a substantially uniformly curved central area of a cornea;

the partially hydrated lens is more steeply curved than the lens in the equilibrium state; and

the lens flattens while expanding into the equilibrium state, centering itself on the central area of the cornea as it flattens.

16. The method according to claim 12, wherein the partially hydrated lens comprises an amount of fluid selected to create an osmotic pressure gradient against stromal fluids when the partially hydrated lens is implanted in the stroma of a cornea, the osmotic pressure gradient causing enhanced adhesion of the lens to the stroma.

17. The method according to claim 12, comprising wetting a prehydrated lens to a partially hydrated state prior to the step of implanting the pre-hydrated lens in the cornea.

18. The method according to claim 17, wherein of wetting a pre-hydrated lens to a partially hydrated state comprises soaking the pre-hydrated lens in a hypertonic solution.

19. The method according to claim 12, further comprising allowing the lens to adhere to the cornea.