Microperimetry.
In SLO microperimetry a multi-channel overlay graphics frame grabber synchronizes the scanning of an infra-red laser with the modulation of a visible laser source. Graphics are created in the laser raster with a fast 25 ns sub-pixel rise-time 80 MHz acousto-optic modulator, Bragg angle optimized for 532 nm, 543.5 nm, 632.8 nm or 660 nm wavelengths over a 40 dB attenuation range. Our software kernel comprises 4 alternative forced choice (4AFC), parameter estimation by sequential testing (PEST) and manual or automated tracking algorithms based on two-dimensional normalized gray-scale correlation. They enable fast and accurate registration of fixation patterns, precise measurements of potential acuities and retinal sensitivity using a range of background illumination levels. Opto-electronic characteristics of physiologic significance are discussed. Clinical examples are given.
Van de Velde
F J
FJ
The Schepens Retina Associates Foundation and SERI, Harvard University, Boston, MA, USA. vdv@sloresearch.org
D000465:Algorithms; D003196:Computer Graphics; D005654:Fundus Oculi; D006801:Humans; D007834:Lasers; D008268:Macular Degeneration / Q000175:diagnosis / Q000534:rehabilitation; D008297:Male; D008875:Middle Aged; D019721:Ophthalmoscopes; D012164:Retinal Diseases / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D012985:Software Design; D015354:Vision, Low / Q000175:diagnosis; D014792:Visual Acuity; D058609:Visual Field Tests / Q000295:instrumentation* / Q000379:methods