Measuring rod and cone dynamics in age-related maculopathy

Abstract

PURPOSE. A cathode-ray-tube (CRT) monitor-based technique was used to isolate clinically significant components of dark adaptation. The utility of the technique in identifying adaptation abnormalities in eyes with age-related maculopathy (ARM) is described. METHODS. A CRT dark adaptometer was developed to assess cone and rod recovery after photopigment bleach. The following measures were obtained: cone recovery rate (Rc; in decades per minute) and absolute threshold (Tfc; log candelas per square meter), rod recovery rate (Rr; decades per minute), and rod-cone transition (rod-cone break [RCB], in minutes). These components were isolated by appropriately selecting stimulus size, stimulus locat..