Method and apparatus for lowering the intraocular pressure of an eye

• US 5,704,907 A
• Filed: 12/11/1995
• Issued: 01/06/1998
• Est. Priority Date: 07/22/1994
• Status: Expired due to Term

• Current Assignee: Wound Healing of Oklahoma
• Original Assignee: Wound Healing of Oklahoma
• Inventors: Li, Bing, Nordquist, Robert E.
• Primary Examiner(s): JONES, MARYBETH O
• Application Number:
  US08/570,400
• Time in Patent Office: 757 Days
• Field of Search: 604/8-10, 604/294, 623/4-6, 424/427
• US Class Current: 604/8
• CPC Class Codes: A61F 9/00781 Apparatus for modifying intraocular pressure, e.g. for glaucoma treatment drainage implants in general A61M27/002

Abstract

A method and apparatus for lowering the intraocular pressure of an eye are provided. The apparatus of the invention is a filtering implant comprising a cellulosic membrane adapted to extend from the anterior chamber of the eye through an opening in the limbus corneae to a drainage area beneath a scleral flap. In its most preferred embodiment, the cellulosic membrane consists essentially of a homopolymer of glucose units connected in a 1,4'"'"'-β linkage. The implant is of a planar, generally rectangular shape. The method of the invention involves preparing and implanting the device within the eye such that it extends from the anterior chamber of the eye through an opening in the limbus corneae to a drainage area beneath a scleral flap.

Claims

1. An implant for lowering the intraocular pressure of an eye which comprises a planar cellulosic membrane shaped and adapted to extend from the anterior chamber of the eye through an opening in the limbus cornea to a drainage area beneath a scleral flap.

2. The implant according to claim 1, wherein said cellulosic membrane consists essentially of a homopolymer of glucose units connected in a 1,4'"'"'-β

linkage.

3. The implant according to claim 1, wherein said implant is of a generally rectangular shape having a proximal end, a distal end, and outer margins.

4. The implant according to claim 3, wherein said margins of said implant toward said proximal end form a foot portion for placement in the anterior chamber of the eye and a body portion opposed to said foot portion for burial beneath the scleral flap.

5. The implant according to claim 4, wherein said implant has a center cut axially extending from said proximal end toward said distal end such that said foot portion can be folded for easy insertion through the opening in the limbus corneae.

6. The implant according to claim 4, wherein two opposing rectangular notches are formed in said margins toward said proximal end so as to form said foot portion.

7. The implant according to claim 4, wherein said implant is of a thickness of approximately 25-150 microns.

8. The implant according to claim 7, wherein the overall length of said implant is approximately 8-10 mm and the overall width is approximately 6 mm.

9. An implant for lowering the intraocular pressure of an eye which comprises a cellulosic membrane consisting essentially of a homopolymer of glucose units connected in a 1,4'"'"'-β

linkage adapted to extend from the anterior chamber of the eye through an opening in the limbus corneae to a drainage area beneath a scleral flap, said implant being of a planar, generally rectangular shape and having a proximal end, a distal end, and outer margins, said margins toward said proximal end forming a foot portion for placement in the anterior chamber and a body portion opposed to said foot portion for burial beneath the scleral flap, said implant having a center cut axially extending from said proximal end toward said distal end such that said foot portion can be folded for easy insertion through the opening in the limbus corneae.

10. The implant according to claim 9, wherein said implant is of a thickness of approximately 25-150 microns.

11. The implant according to claim 10, wherein the overall length of said implant is approximately 8-10 mm and the overall width is approximately 6 mm.

12. The implant according to claim 9, wherein two opposing rectangular notches are formed in said margins toward said proximal end so as to form said foot portion.

13. The implant according to claim 12, wherein said foot portion has a length of approximately 1 mm and a width of approximately 6 mm, said two opposing rectangular notches measure approximately 1 mm in length and 1.5 mm in width, and said body portion has a length of approximately 8 mm and a width of approximately 6 mm.

14. The implant according to claim 9, wherein said foot portion is provided with at least one curved, resilient arm member radially extending therefrom for abutting the inner surface of the limbus corneae after implantation so as to maintain the post-surgical position of said implant.

15. The implant according to claim 14, wherein said arm member is formed of polypropylene and is glued to said foot portion with a cyanoacrylate surgical adhesive.

16. The implant according to claim 14, wherein said arm member is formed of polymethylacrylate and is polymerized integrally to said foot portion.

17. An implant for lowering the intraocular pressure of an eye which comprises a cellulosic membrane consisting essentially of a homopolymer of glucose units connected in a 1,4'"'"'-β

linkage adapted to extend from the anterior chamber of the eye through an opening in the limbus corneae to a drainage area beneath a scleral flap, said implant being of a planar, generally rectangular shape and having a proximal end and a distal end, said proximal end having an integrally formed key projecting therefrom for placement through said opening and into said anterior chamber, said key having at least one curved, resilient arm member radially extending therefrom for abutting the inner surface of the limbus corneae after implantation so as to maintain the post-surgical position of said implant.

18. The implant according to claim 17, wherein said key is center cut to divide said key into a first piece and a second piece such that said key can be folded for easy insertion through the opening in the limbus corneae.

19. The implant according to claim 18, wherein said key has two curved, resilient arm members, a first arm member radially extending from said first piece and a second arm member radially extending from said second piece.

20. The implant according to claim 17, wherein said arm member is formed of polypropylene and is glued to said key with a cyanoacrylate surgical adhesive.

21. The implant according to claim 17, wherein said arm member is formed of polymethylacrylate and is polymerized integrally to said key.

22. A method for lowering the intraocular pressure of an eye, which comprises positioning an implant within the eye such that said implant comprises a pre-formed cellulosic membrane, said membrane extends from the anterior chamber of the eye through an opening in the limbus cornea to a drainage area beneath a scleral flap.

23. The method according to claim 22, wherein said cellulosic membrane consists essentially of a homopolymer of glucose units connected in a 1,4'"'"'-β

linkage.

24. The method according to claim 23, wherein said implant is of a planar, generally rectangular shape having a proximal end, a distal end, and outer margins, said margins toward said proximal end forming a foot portion for placement in the anterior chamber and a body portion opposed to said foot portion for burial beneath the scleral flap.

25. The method according to claim 24, wherein said implant has a center cut axially extending from said proximal end toward said distal end such that said foot portion can be folded for easy insertion through the opening in the limbus corneae.

26. The method according to claim 24, wherein said implant is of a thickness of approximately 25-150 microns.

27. The method according to claim 24, wherein the overall length of said implant is approximately 8-10 mm and the overall width is approximately 6 mm.

28. The method according to claim 24, wherein two opposing rectangular notches are formed in said margins toward said proximal end so as to form said foot portion.

29. The method according to claim 28, wherein said foot portion has a length of approximately 1 mm and a width of approximately 6 mm, said two opposing rectangular notches measure approximately 1 mm in length and 1.5 mm in width, and said body portion has a length of approximately 8 mm and a width of approximately 6 mm.

30. The method according to claim 24, wherein said foot portion is provided with at least one curved, resilient arm member radially extending therefrom for abutting the inner surface of the limbus corneae after implantation so as to maintain the post-surgical position of said implant.

31. The method according to claim 30, wherein said arm member is formed of polypropylene and is glued to said foot portion with a cyanoacrylate surgical adhesive.

32. The method according to claim 30, wherein said arm member is formed of polymethylacrylate and is polymerized integrally to said foot portion.

33. A method for lowering the intraocular pressure of an eye, which comprises positioning an implant within the eye such that said implant extends from the anterior chamber of the eye through an opening in the limbus corneae to a drainage area beneath a scleral flap, said implant comprising a pre-formed cellulosic membrane consisting essentially of a homopolymer of glucose units connected in a 1,4'"'"'-β

linkage, said implant being of a planar, generally rectangular shape and having a proximal end and a distal end, said proximal end having an integrally formed key projecting therefrom for placement through said opening and into said anterior chamber, said key having at least one curved, resilient arm member radially extending therefrom for abutting the inner surface of the limbus corneae after implantation so as to maintain the post-surgical position of said implant.

34. The method according to claim 33, wherein said key is center cut to divide said key into a first piece and a second piece such that said key can be folded for easy insertion through the opening in the limbus corneae.

35. The method according to claim 34, wherein said key has two curved, resilient arm members, a first arm member radially extending from said first piece and a second arm member radially extending from said second piece.

36. The method according to claim 33, wherein said arm member is formed of polypropylene and is glued to said key with a cyanoacrylate surgical adhesive.

37. The method according to claim 33, wherein said arm member is formed of polymethylacrylate and is polymerized integrally to said key.

38. A method for lowering the intraocular pressure of an eye, which comprises the steps of:

(a) die cutting a cellulosic membrane into a planar, generally rectangular shape to form an implant, said implant having a proximal end, a distal end, and outer margins, said margins toward said proximal end being altered so as to form a foot portion and a body portion;

(b) thoroughly rinsing said cellulosic membrane in distilled water;

(c) heating said cellulosic membrane to 100°

C. for 30 minutes in 2% sodium bicarbonate and 1% ethylenediuminetetraacetic acid;

(d) cooling said cellulosic membrane at 4°

C. in 2% formaldehyde or balanced saline solution;

(e) rinsing said cellulosic membrane in a balanced saline solution;

(f) implanting said implant within the eye such that said foot portion extends into the anterior chamber of the eye through an opening in the limbus corneae and said body portion is buried beneath a scleral flap.

39. A method for lowering the intraocular pressure of an eye, which comprises the steps of:

(a) making an 8 mm cord length conjunctival incision 8-10 mm posterior to the surgical limbus of the eye in the desired quadrant;

(b) forming a conjunctival flap by dissecting the conjunctiva from Tenon'"'"'s capsule;

(c) forming a scleral flap by cauterizing an area of the sclera to define the perimeter of said scleral flap, outlining the margins of said scleral flap with partial thickness incisions, and dissecting, starting posteriorly, the outlined sclera to obtain said scleral flap;

(e) positioning an implant within the eye such that said implant extends from the anterior chamber of the eye through the opening in the limbus corneae to a drainage area beneath said scleral flap, said implant comprising a pre-formed cellulosic membrane consisting essentially of a homopolymer of glucose units connected in a 1,4'"'"'-β

linkage;

(f) suturing said scleral flap and said implant to the sclera; and

(g) closing the conjunctiva and Tenon'"'"'s capsule with sutures.