Phacophotolysis method and apparatus

• US 20020123744A1
• Filed: 12/28/2000
• Published: 09/05/2002
• Est. Priority Date: 12/28/2000
• Status: Active Grant

• Current Assignee: Reynard, Michael
• Original Assignee: Reynard, Michael
• Inventors: Reynard, Michael
• Granted Patent: US 6,520,955 B2
• Time in Patent Office: Days
• US Class Current: 606/6
• CPC Class Codes: A61F 2/1662 Instruments for inserting intraocular lenses into the eye
• CPC Class Codes: A61F 2009/00842 Permanent Structural Change [PSC] in index of refraction; Limit between ablation and plasma ignition
• CPC Class Codes: A61F 2009/0087 Lens
• CPC Class Codes: A61F 2009/00887 Cataract
• CPC Class Codes: A61F 2009/00889 Capsulotomy
• CPC Class Codes: A61F 9/00736 Instruments for removal of intra-ocular material or intra-ocular injection, e.g. cataract instruments A61F9/008 takes precedence
• CPC Class Codes: A61F 9/0079 using non-laser electromagnetic radiation, e.g. non-coherent light or microwaves
• CPC Class Codes: A61F 9/008 using laser
• CPC Class Codes: A61F 9/00802 for photoablation
• CPC Class Codes: A61M 2210/0612 Eyes
• CPC Class Codes: A61N 5/062 Photodynamic therapy, i.e. excitation of an agent

Abstract

A process and apparatus for removing cataractous lens tissue (22) in a human or animal eye and substitution of the lens with replacement material (48) utilizing an apparatus in the form of a surgical instrument (42). The process contains the steps of injecting a therapeutic photosensitive agent (20) into the lens tissue, allowing a predetermined amount of time to elapse, exposing the photosensitive substance to a source of light energy at a predetermined period of time and wavelength causing the lens to microfracture and liquefy. Following this procedure the liquefied lens tissue is evacuated with the surgical instrument, and a lens replacement material is injected into the lens capsule (28) through the surgical instrument to reconstitute the intralenticular space and serve as a refracting medium. The dual cannula surgical instrument consists of a hollow cylindrical body (52) with a parallel shank (58) and a tapered section (60) on one end. An outer hollow needle (62) attached to the tapered section and an inner hollow needle (64) is axially disposed within the body and outer needle with both needles terminating at the same end. The opposite end of the body is in communication with an aspiration and infusion apparatus for withdrawing decomposed cataractous lens tissue under negative pressure and for supplying irrigation fluids.

Claims

1. A process for removing cataractous lens tissue and substitution thereof with a lens replacement material utilizing a surgical instrument which comprises the steps of

a) injecting a therapeutic photosensitive agent into the cataractous lens tissue of a human or animal eye,

b) allowing a predetermined amount of time to elapse, dependent upon cataractous lens tissue density and amount of penetration of the therapeutic photosensitive agent,

c) exposing the therapeutic photosensitive substance to a source of light energy for a predetermined period of time and wavelength causing the lens to microfracture and liquefy,

d) evacuating the liquefied lens tissue with a surgical instrument, and

e) injecting lens replacement material within the human'"'"'s or animal'"'"'s lens capsule through said surgical instrument to reconstitute the lens tissue intralenticular space and serve as a refracting medium.

2. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said photosensitive agent is composed of a substance that has the propensity to destroy ocular lens tissue.

3. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said photosensitive agent further comprises at least one component selected from the group consisting of chlorins, merocyanine, porphyrins, pheophorbides, purpurins, iminium salts, phthalocyanines, porphycenes, psoralen and verdins.

4. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said photosensitive agent further comprises a green porphyrin liposomal preparation.

5. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said photosensitive agent is complexed with low-density lipoprotein.

6. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said photosensitive agent further comprises a polypyrrolic macrocycle.

7. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said photosensitive agent is chemically bound to an agent specifically reactive to lens tissue.

8. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said photosensitive agent further comprises a combination of dissimilar agents.

9. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 8 wherein said combination of dissimilar agents is selected from the group consisting of protease, lipase and carbohydrase.

10. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said photosensitive agent is confined to the intracapsular space by occlusion of the lens capsule injection site with a non-toxic polymer.

11. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 10 wherein said non-toxic polymer is selected from the group consisting of carageenan, collagen, hyaluronic acid, pectin, and xanthan gum.

12. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said source of light is selected from the group consisting of a laser, a light emitting diode and an incandescent lamp.

13. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said source of light is a pulsed light of a wavelength and flux selected such that the lens in its ground state absorbs radiation and rises to an excited state and this state absorbs further radiation therefore rising to a higher state ultimately achieving photolysis.

14. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said source of light is comprised of laser pulses having essentially the same wavelength.

15. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 14 wherein each laser pulse has a wavelength within the range of 180 to 290 nm, a duration less than 1×

10<sub>−

5</sub> seconds and a flux greater than 1×

10₁₅ photons per square centimeter.

16. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 14 wherein each laser pulse has a wavelength from 220 nm to 290 nm, a duration of less than from 5×

10<sub>−

9</sub> seconds to 1×

10_{31 5} seconds and a flux greater than from 1×

10₅ photons to 1×

10₁₈ photons per square centimeter.

17. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 14 wherein each laser pulse has a wavelength from 220 nm to 280 nm, a duration of less than from 5×

10<sub>−

10</sub> seconds to 1×

10<sub>−

12</sub> seconds and a flux greater than from 1×

10₁₇ photons to 1×

10₁₈ photons per square centimeter.

18. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said pulsed light is comprised of laser pulses having essentially a different wavelength.

19. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 18 wherein said source of light further comprises at least one first pulsed light of a wavelength and flux selected such that the lens proteins in their ground state absorbs radiation and rises to an excited state and at least one additional pulse of a wavelength and flux selected such that said lens in their excited state absorb and undergo photolysis.

20. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 19 wherein said excited state of the lens nucleic acids are selected from the singlet state and the triplet state and wherein said additional pulses are applied during the lifetime of said excited states of nucleic acids.

21. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 19 wherein said additional pulse further comprises a second pulse.

22. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 21 wherein said second pulse is applied within one microsecond after each first pulse is applied.

23. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 19 wherein said additional pulse is simultaneously applied.

24. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 19 wherein said first and second pulse are applied in alternating sequences of more than one pulse each.

25. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 19 wherein said first and second pulse are, applied in alternating sequences of one pulse each.

26. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said source of light energy is delivered to the lens by an optical fiber within the surgical instrument which radially diffuses the light.

27. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said lens replacement material further comprises an elastomer.

28. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said lens replacement material further a photosensitive resin.

29. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said lens replacement material further a non-immunogenic and biocompatable thermoplastic.

30. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said lens replacement material is non-flowable at temperatures below 39 degrees C. and flowable at temperatures not higher than 45 degrees C.

31. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said lens replacement material further comprises a synthetic polymer.

32. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said lens replacement material further comprises a polymer having at least one additive.

33. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 32 wherein said additive is a curing catalyst.

34. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said lens replacement material is selected from the group consisting acrylate, polymethylmethacrylate, methacrylate, silicone, styrene, thermopolymer, photosensitive resin, plastic polymer, cyclohexane, organopolymer, or organopolysiloxane.

35. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said lens replacement material forms a lens in situ which is optically clear and chemically stable in the presence of bodily fluids.

36. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 further comprising an additional step of inserting a balloon into the intralenticular space of a human or animal eye prior to injecting lens replacement material and injecting lens replacement material into the balloon to reconstitute the lens and serve as a refracting medium.

37. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 36 wherein said balloon is made of a substance selected from the group consisting of hydroxymethylmethacrylate, polymethylmethacrylate, polyethelene, polystyrene, polypropylene, polytetrafluorethylene, polybutylene teraphthalate, polyether glycol, ethyl-vinyl-acetate, and silicone.

38. The process for removing cataractous lens tissue and substitution thereof with a lens replacement material as recited in claim 1 wherein said liquefaction of lens tissue can be enhanced by means of combining phacolytic chemicals with a conveyer fluid, heated to temperature ranging from 10 degrees to 220 degrees Farenheit.

41. The dual cannula surgical instrument as recited in claim 39 further comprising an internal divider disposed within the body contiguous with both the body and the inner hollow needle permitting dual function of the instrument simultaneously including infusion and aspiration functions of fluid materials.

42. The dual cannula surgical instrument as recited in claim 39 further comprising a fiber optical strand removably disposed within the inner hollow needle for conducting light energy to the cataractous lens tissue.

39. A process for removing cataractous lens tissue and substitution with a lens replacement material in a human or animal which comprises the steps of:

a) injecting into the cataractous lens tissue an effective amount of therapeutic photosensitive agent,

b) exposing the therapeutic photosensitive substance to a source of light energy causing the lens to liquefy,

c) evacuating the liquefied lens tissue with a surgical instrument, and

d) injecting lens replacement material within the intralenticular space of a human or animal eye to reconstitute the lens and serve as a refracting medium.

40. A dual cannula surgical instrument for introducing a therapeutic photosensitive agent into lens tissue of a human or animal eye, evacuating decomposed lens tissue while simultaneously maintaining intralenticular pressure and introducing a lens replacement material comprising:

a) a hollow cylindrical body having a first end and a second end,

b) said body having a parallel shank and tapered section on the second end,

c) an outer hollow needle is attached to the tapered section of the second end,

d) an inner hollow needle axially disposed within the body and outer needle, said inner needle terminating at the body'"'"'s second end, for introducing fluids and tubular items into the lens capsule, and

e) said body second end in communication with aspiration an infusion apparatus for withdrawing decomposed cataractous lens tissue under negative pressure and supplying irrigation fluids.