Variability in bleach kinetics and amount of photopigment between individual foveal cones

Abstract

PURPOSE. To study the bleaching dynamics of individual foveal cone photoreceptors using an adaptive optics ophthalmoscope. METHODS. After dark adaptation, cones were progressively bleached and imaged by a series of flashes of 545-nm to 570-nm light at 12 Hz. Intensity measurements were made within the foveal avascular zone (FAZ) to avoid confounding signals from the inner retinal blood supply. Over 1300 cones in this region were identified and tracked through the imaging sequences. A single subject was used who demonstrated the necessary steady fixation, wide FAZ, and resolvability of cones close to the foveal center. RESULTS. The mean intensity of all cones was well-described by first-order..