Abstract
An optical guide dispenses laser light that is incident outside a selected region during laser eye surgery. The guide is formed as a body with a passageway of selected geometrical cross-section that defines a mininmum optical opening. The body has a material which circumferentially surrounds the passageway that is effective to dispense laser light incident thereto such that the energy thereof is dissipated to a level that will not affect eye tissue. A handle may optionally be provided to facilitate manipulation of the body. The passageway is preferably frustoconical. An optical system incorporates the optical guide and includes a mount that is to be placed in contact with the eye. The optical guide is secured to the mount, such as by cooperative rails and protrusions. A method is described to perform laser eye surgery using such optical guide and directing laser light along an optical path parallel to the central axis of the passageway. The laser light beam is...
Filing date: Apr 26, 1996
Issue date: Sep 15, 1998
Inventor: Jon G. Dishler
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What is claimed is:
1. An optical guide adapted for use in laser surgery of an eye and operative to disperse laser light of a selected energy which is incident outside of a selected region, said optical guide comprising a body having a passageway therethrough and a sidewall surrounding said passageway, said passageway having a selected geometrical cross-section that defines a minimum optical opening having a periphery of a selected configuration through which the laser light may pass, said body constructed of a material that is effective in dispersing the laser light which is incident thereto such that the energy thereof is dissipated to a level that will not affect eye tissues.
2. An optical guide according to claim 1 wherein said body is annular in shape with said passageway defined by an inner sidewall of said body.
3. An optical guide according to claim 2 wherein said passageway is frustoconical in shape such that said sidewall is angularly divergent.
4. An optical guide according to claim 3 wherein said sidewall has an angle of divergence of about thirty degrees.
5. An optical guide according to claim 3 wherein said passageway is frustoconical in shape such that said sidewall is angularly divergent.
6. An optical guide according to claim 1 wherein the passageway extends axially through said body.
7. An optical guide according to claim 1 wherein said body portion is fabricated of a plastic material.
8. An optical system adapted for use in corrective eye surgery wherein focusing optics directs a beam of laser light from a laser light source of a selected energy along an optical path that is incident onto tissues of an eye, said energy being such that cellular eye tissue is removed by the laser light directly incident thereto, and wherein a control system is provided to control the size of the beam of laser light and a tracking path therefor, said optical system comprising:
- (a) a mount operative to be placed in contact with the eye over a region targeted for laser surgery; and
- (b) an optical guide adapted to be secured to said mount, said optical guide including a body portion having an axial passageway extending therethrough between a top and a bottom thereof and an inner sidewall surrounding said axial passageway, said axial passageway having a selected geometrical cross-section that defines a minimum optical opening having a periphery of a selected configuration through which the laser may pass in an axial direction, said body constructed of a material that is effective in dispersing the laser light which is incident thereto such that the energy thereof is dissipated to a level that will not affect eye tissues.
9. An optical guide according to claim 8 wherein said body is annular in shape with said passageway defined by an inner sidewall of said body.
10. An optical guide according to claim 8 wherein said mount is a suction ring.
11. A method of performing laser eye surgery for correction of hyperopia comprising the steps of:
- (a) preparing an eye to have an exposed section of corneal tissue;
- (b) disposing an optical guide proximate to said section of corneal tissue, said optical guide including a body portion having an axial passageway therethrough which permits unobstructed passage of axial laser light through an operative region surrounded by a sidewall of said optical guide, said operative region having a surrounding periphery of a selected configuration and a center point with said axial passageway having a central axis passing through the center point;
- (c) directing a beam of laser light at a selected energy sufficient to remove corneal tissue cells along an optical path that is parallel to the central axis such that said laser beam is incident to said exposed section with said beam of laser light having a central area of maximum intensity, said beam of laser light being sized to have a diameter that is greater than a radial dimension of the operative region and positioned such that the central area thereof is offset from the center point whereby an active portion of light will pass through said axial passageway and wherein an inactive portion of said laser light will be incident to said body portion, said sidewall constructed of a material that is effective in dispersing the energy of said laser cells; and
- (d) moving the beam of laser light such that the central area thereof follows a pathway that surrounds the central point whereby a recess is formed by removal of corneal tissue cells, said recess having a greatest depth along a medial area of the pathway.
12. A method according to claim 11 wherein the diameter of said beam is varied as said beam is moved along the pathway.
13. A method according to claim 12 wherein the diameter is expanded as said beam is moved along the pathway.
14. A method according to claim 12 wherein said central area is disposed 2.5-3.5 millimeters from the center point.
15. A method according to claim 14 wherein the diameter of said beam is varied between 1.0 millimeters and 5.0 millimeters.
16. A method according to claim 11 wherein said pathway is a geometrical shape selected from a group consisting of: circular pathways and ovoid pathways.
17. An optical guide adapted for use in laser surgery of an eye and operative to disperse laser light of a selected energy which is incident outside of a selected region, said optical guide comprising:
- (a) a body having a passageway therethrough and a sidewall surrounding said passageway, said passageway having a selected geometrical cross-section that defines a minimum optical opening having a periphery of a selected configuration through which the laser light may pass, said body constructed of a material that is effective in dispersing the laser light which is incident thereto such that the energy thereof is dissipated to a level that will not affect eye tissues; and
- (b) a handle member secured to said body and operative to facilitate manipulation thereof.
18. An optical guide adapted for use in laser surgery of an eye and operative to disperse laser light of a selected energy which is incident outside of a selected region, said optical guide comprising a body having a passageway therethrough and a sidewall surrounding said passageway, said passageway having a selected geometrical cross-section that defines a minimum optical opening having a periphery of a selected configuration through which the laser light may pass, said body constructed of a material that is effective in dispersing the laser light which is incident thereto such that the energy thereof is dissipated to a level that will not affect eye tissues, said material being selected from a group consisting of plastic and glass.
19. An optical system adapted for use in corrective eve surgery wherein focusing optics directs a beam of laser light from a laser light source of a selected energy along an optical path that is incident onto tissues of an eye, said energy being such that cellular eye tissue is removed by the laser light directly incident thereto, and wherein a control system is provided to control the size of the beam of laser light and a tracking path therefor, said optical system comprising:
- (a) a mount operative to be placed in contact with the eye over a region targeted for laser surgery, said mount including a pair of parallel rail elements in spaced-apart facing relationship; and
- (b) an optical guide adapted to be secured to said mount and including an engagement structure sized and configured to engage said rails thereby to assist in securing said optical guide to said mount, said mount further including a body portion having an axial passageway extending therethrough between a top and bottom thereof and an inner sidewall surrounding said axial passageway, said axial passageway having a selected geometrical cross-section that defines a minimum optical opening having a periphery of a selected configuration through which the laser may pass, said body constructed of a material that is effective in dispersing the laser light which is incident thereto such that the energy thereof is dissipated to a level that will not affect eye tissues.
20. An optical guide according to claim 19 wherein said engagement structure includes a foot portion operative to engage one of said rails.
21. An optical guide according to claim 20 wherein said engagement structure includes a shoulder portion disposed oppositely of said foot portion and operative to engage another of said rails, said mount including a retaining element operative to bear against said body portion to retain said body portion to retain said foot and shoulder portions in engagement with said rails.
22. An optical guide according to claim 21 wherein said retaining element is resiliently biased against said body portion when said optical guide is secured to said mount.