Method and apparatus for early detection of glaucoma
US5912723A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 24, 1996 |
| Grant date | Jun 15, 1999 |
| Priority date | — |
| Expiry date | Oct 24, 2016 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B3/06
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A diagnostic test for glaucoma which preferably uses four types of frequency doubled illusion patterns to determine the existence of glaucomatous damage in different regions of the eye. The four frequency doubled illusion patterns are preferably generated on a cathode ray tube by single spatial frequencies in the range of 0.1 to 4.0 cycles per degree whose contrast is modulated in time at between 10 and 50 Hz. As the contrast of each of these patterns is lessened, a threshold value is determined for each pattern at the point where the subject can only discern thick vertical stripes in the test pattern rather than the frequency doubled illusion. By comparing the detected threshold values for the various patterns among themselves and with other test data for normal sighted persons, the presence of glaucomatous damage to different regions of the eye can be detected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.