Rod and Cone Mediated Function in Retinal Disease

National Eye Institute

Investigators

Linked publications, trials & patents

Abstract

Specific Aim 1: To establish the normal ranges of dark-adapted retinal sensitivities for the Medmont, and for RF hyperacuity function on the Display++ monitor in healthy volunteers. We have established normal range for the Medmont dark adaptometer and RF hyperacuity measures for the Display++. Since the last continuing review, we have amended this protocol to add new fundus-guided and non-guided perimeters to the protocol. We are in the process of establishing normal ranges for these other perimeters. Specific Aim 2: To establish the normal ranges for the kinetics of dark adaptation for the Medmont DAC blue and red stimuli in healthy volunteers. We have established the normal range for dark adaptation with the Medmont dark adaptometer. We are in the process of establishing normal range for another perimeter that measures dark adaptation. Specific Aim 3: To quantify local changes in rod and cone photoreceptor function across the retina in participants with retinal disease. We have studied rod function and dark adaptation, from seven members of a family with late-onset retinal degeneration (L-ORD). We have followed several members longitudinally and plan to continue following these patients. We developed a new test of rod function based on scotopic contour and shape discrimination (Flynn and Jeffrey, PMID: 30747948). We used this test to investigate early changes in rod function in participants with intermediate age-related macular degeneration (iAMD) with or without reticular pseudodrusen (RPD). We found that our novel shape discrimination test revealed evidence of rod-mediated dysfunction in a subset of iAMD participants who had normal scotopic thresholds and normal dark adaptation. For the RPD participants, the shape test also detected changes in rod-mediated function in a subset of this group who had normal scotopic thresholds, although these RPD participants also had delayed dark adaptation. The results of this study have been accepted for publication (Jeffrey et al. PMID 35749129)