Laser surgery method
US5108388A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 16, 1987 |
| Grant date | Apr 28, 1992 |
| Priority date | — |
| Expiry date | Oct 16, 2007 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61F2009/00872
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
An argon-flouride excimer laser or other laser source capable of generating far-ultraviolet radiation at 193 nm is pulsed with energy densities of greater than 20 mj per cm.sup.2 at a repetition rate up to 25 pulses per second to direct its radiation through a mask and onto corneal tissue, or other biological matter, to form a groove therein of predetermined configuration and depth by a process of ablative photodecomposition. The masks are formed with a slit, circular, crescent or other openings of widths between 30 and 800 microns, and may even be formed to provide a graded intensity center to edge. The mask is reflective or composed of or faced with an organic polymer to prevent heat build-up. Each micron of the depth of a 200 micron deep groove formed in corneal tissue, for example, resulted from the application of 1 joule per square centimeter of radiation, from a series of pulses delivered at intensities of between 100 mj and 200 mj per square centimeter and at a laser pulse rate of between 1 and 25 Hertz; the entire groove taking 100 seconds.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.