Intraocular lenses

• US 4,731,079 A
• Filed: 11/26/1986
• Issued: 03/15/1988
• Est. Priority Date: 11/26/1986
• Status: Expired due to Term

• Current Assignee: CIBA Vision AG (Novartis Ag)
• Original Assignee: Kingston Technology Incorporated (Kingston Technology Corporation)
• Inventors: Stoy, Vladimir
• Primary Examiner(s): FRINKS, RONALD
• Application Number:
  US06/935,224
• Time in Patent Office: 475 Days
• Field of Search: 623/6, 206/5.1, 128/303 R
• US Class Current: 623/6.58
• CPC Class Codes: A61F 2/16 Intraocular lenses
• CPC Class Codes: A61F 2/1613 having special lens configurations, e.g. multipart lenses; having particular optical properties, e.g. pseudo-accommodative lenses, lenses having aberration corrections, diffractive lenses, lenses for variably absorbing electromagnetic radiation, lenses having variable focus
• CPC Class Codes: A61F 2/1616 Pseudo-accommodative, e.g. multifocal or enabling monovision
• CPC Class Codes: A61F 2/1664 for manual insertion during surgery, e.g. forceps-like instruments
• CPC Class Codes: A61L 2430/16 for reconstruction of eye parts, e.g. intraocular lens, cornea
• CPC Class Codes: A61L 27/52 Hydrogels or hydrocolloids
• CPC Class Codes: B29C 61/06 Making preforms having internal stresses, e.g. plastic memory
• CPC Class Codes: B29D 11/023 Implants for natural eyes
• CPC Class Codes: B29L 2011/0041 Contact lenses

Abstract

There is provided a novel intraocular lens and mode of insertion therefore. The lens is of conventional shape and dimensions but is made of polymeric material having a softening point in the range of body temperature. The lens, prior to insertion is dimensionally reduced to enable introduction thru a small incision by compression or by axial extension. The deformed lens is frozen in this configuration by cooling the lens below its softening temperature. The cooled, deformed lens is then inserted into the eye. The action of body heat, optionally supplemented by various non-harmful methods, permits the lens to regain its original configuration within the eye.

Claims

1. In an intraocular lens which includes at least a non-toxic, biocompatible, hydrolytically and enzymatically stable, photodegradation resistant, polymeric optical zone portion,

wherein the improvement comprises said polymeric optical zone portion having the following characteristics, when in osmotic equilibrium with body liquids:

(a) softening temperature T_s between about 0°

C. and about 42°

C.;

(b) damaging temperature T_d higher than 42°

C.;

(c) refractive index greater than 1.39; and

(d) temperature range of elastic deformation Te, above T_s but below T_d, and

when said polymeric optical zone portion is heated to T_e and one of its original dimensions is reduced by at least 20%,

then cooled to at least 5°

C. below T_s and,

upon reheating to T_e said polymeric optical zone portion will return to its original dimensions existing prior to said first heating to T_e, dimensional reduction and cooling.

2. A lens in accordance with claim 1 wherein said polymeric material is plastizable by water or isotonic aqueous solution containing a biocompatible solute.

3. A lens in accordance with claim 1 wherein the polymer is a co-polymer derived from at least two co-monomers.

4. A lens in accordance with claim 3 additionally comprising a cross-linking agent.

5. A lens in accordance with claim 3 wherein at least one of the co-monomers is hydrophilic.

6. A lens in accordance with claim 3 wherein at least one of the co-monomers is hydrophobic.

7. A lens in accordance with claim 6 wherein at least one of the co-monomers is hydrophilic.

8. A lens in accordance with claim 2 comprising an outer hydrogel lens capable of maintaining a water content greater than 90% by weight when inserted in the eye.

9. A lens in accordance with claim 8 wherein the thickness of the hydrogel layer is between 1 and 100 microns after swelling.

10. A sterile package comprising:

a lens of claim 1,

a dimension reducing means capable of reducing the dimension of said lens by at least 20% of its prereduction dimension, in a predetermined direction, after heating to a temperature above T_s and below T_d and autoclavable encapsulating means surrounding said lens and said clamping means.

11. A package according to claim 10 wherein said lens is located within said clamping means.

12. A package according to claim 11 wherein said lens is in the Optical Configuration.

13. A package in accordance with claim 11 wherein said lens has been reduced by at least 20% of its prereduction dimension in a predetermined direction in the Optical Configuration and is maintained in said reduced state by said dimension reducing means.

14. A method of introducing and implanting an artificial intraocular lens for replacement of a surgically removed crystalline lens, through an incision in an eye, comprising the steps of:

providing an intraocular lens of non-toxic, biocompatible, hydrolytically and enzymatically stable, photodegradation resistant, elastomeric, polymeric material having the following characteristics;

(a) T_s between about 0°

C. and about 42°

C.;

(b) T_d above 42°

C.; and

(c) refractive index greater than 1.39;

said lens having an optical axis and an axis transverse thereto designated as the longitudinal axis where said longitudinal axis is substantially coaxial with the direction of insertion of said lens into said incision in said eye;

heating said lens to a temperature above T_s and below T_d ;

reducing at least one dimension of said lens, in a direction transverse to said longitudinal axis, to a dimension at least 20% less than the pre-reduction dimension in said direction;

cooling said lens to a temperature above -5°

C. which is at least 5°

C. less than T_s while maintaining the reduced dimension of the lens;

inserting said lens into said incision in said eye; and

permitting the lens to warm to a temperature below 42°

C. and above T_d ;

whereby said lens will return to its original dimensions of full size and fixed focal length to provide a safer, more convenient surgical procedure and a more comfortable fit in the eye.

15. A method of claim 14, wherein the dimension reduction is provided by tension applied along the longitudinal axis.

16. A method of claim 14 wherein the dimension reduction is prvoided by compression transverse to the longitudinal axis.

17. A method in accordance with claim 14 wherein said polymeric material is plasticizable by water or an isotonic aqueous solution containing a biocompatible solute.

18. A method in accordance with claim 14 wherein the polymer is a co-polymer derived from at least two co-monomers.

19. A method in accordance with claim 18 additionally comprising a cross-linking agent.

20. A method in accordance with claim 18 wherein at least one of the co-monomers is hydrophilic.

21. A method in accordance with claim 18 wherein at least one of the co-monomers is hydrophobic.

22. A method in accordance with claim 21 wherein at least one of the co-monomers is hydrophilic.

23. A method in accordance with claim 14 comprising an outer hydrogel layer capable of maintaining a water content greater than 90% by weight when inserted in the eye.

24. A method in accordance with claim 23 wherein the thickness of the hydrogel layer is between 1 and 100 microns after swelling.