An application of threshold-versus-intensity functions in automated static perimetry.
Increment thresholds were measured over a range of adapting illuminances using a modified automated static perimeter. The data were fitted to a threshold versus intensity model (logT - logT(0) + log((A + A(0))/A(0))n) and the values logT(0) and logA(0) estimated. The effect of eccentricity and age on logT(0) and logA(0) was examined in normal subjects. A small group of patients with ocular disease were then assessed. Macular degeneration appeared to act as disease processes acting near the photoreceptor (d1 model). Glaucoma seemed to act near the site of retinal gain (d3 model). This analysis method may be of value in developing light adaptation strategies in people with ocular disease.
Herse
Peter
P
School of Optometry and Vision Science, University of New South Wales, Sydney, NSW 2053, Australia. p.herse@unsw.edu.au
D000221:Adaptation, Ocular; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology; D005260:Female; D005902:Glaucoma, Open-Angle / Q000503:physiopathology* / Q000534:rehabilitation; D006801:Humans; D008029:Lighting; D008268:Macular Degeneration / Q000503:physiopathology* / Q000534:rehabilitation; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D011601:Psychophysics; D012684:Sensory Thresholds; D014792:Visual Acuity; D058609:Visual Field Tests / Q000379:methods*