Glaucoma laser trabeculodissection

• US 5,549,598 A
• Filed: 05/22/1995
• Issued: 08/27/1996
• Est. Priority Date: 05/22/1995
• Status: Expired due to Fees

• Current Assignee: O'Donnell, Francis E. Jr.
• Original Assignee: O'Donnell, Francis E. Jr.
• Inventors: O'Donnell, Francis E. Jr.
• Primary Examiner(s): Shay, David M.
• Application Number:
  US08/445,898
• Time in Patent Office: 463 Days
• Field of Search: 606/2, 606/3-6, 606/10-13
• US Class Current: 606/6
• CPC Class Codes: A61F 2009/00853 Laser thermal keratoplasty or radial keratotomy
• CPC Class Codes: A61F 2009/00868 Ciliary muscles or trabecular meshwork
• CPC Class Codes: A61F 2009/00891 Glaucoma
• CPC Class Codes: A61F 2009/00897 Scanning mechanisms or algorithms
• CPC Class Codes: A61F 9/00802 for photoablation

Abstract

A method for performing a trabeculodissection comprising the steps of forming a scleral flap, determining the treatment arc of tissue located under the scleral flap, designating a number of discrete test areas along the treatment arc under the scleral flap, performing test ablations within the discrete test areas with a galvanometric scanning laser delivery system, determing the discrete treatment zones corresponding to the test areas, programming the galvanometric scanning laser delivery system based upon the results of the test ablations, ablating the tissue, and repairing the sclearal flap.

Claims

1. A method of performing trabeculodissection comprising performing a laser ablation in discrete treatment areas along a defined treatment arc of the trabecular meshwork to obtain equal residual depth along the treatment arc despite the fact that the trabecular meshwork varies in thickness along the length of the treatment arc.

2. The method of claim 1 wherein the step of ablating in discrete treatment areas includes preventing filtration through a previously ablated area from interfering with the ablation in a subsequent treatment area.

3. A method for performing a trabeculodissection comprising the steps of:

fashioning a scleral flap;

determining a treatment arc of tissue under the scleral flap;

designating a number of discrete test areas along the treatment arc under the scleral flap;

performing test ablations within the discrete test areas with a galvanometric scanning laser delivery system;

evaluating the test ablations;

designating a number of discrete treatment zones corresponding to the discrete test areas along the treatment arc;

programming the galvanometric scanning laser delivery system based upon the results of the test ablations;

ablating the tissue in the discrete treatment zones to a sufficient depth to allow for adequate drainage of aqueous humor; and

repairing the scleral flap.

4. The method of claim 3 wherein the step of fashioning includes fashioning the scleral flap with a diamond knife with a blade extension of 400 microns.

5. The method of claim 3 wherein the step of programming includes programming the galvanometric scanning laser delivery system for a low but suprathreshold fluence.

6. The method of claim 5 wherein the step of programming the low but suprathreshold fluence further comprises the step of programming the fluence to be less than 120 mJ/cm² to reduce a risk of full thickness penetration.

7. The method of claim 6 further includes the step of setting the pulse frequency between 60 to 300 hertz.