Bradyopsia is a rare retinal disorder, first described in 3 unrelated Dutch families.1 Patients with bradyopsia have difficulty tracking moving objects and adapting to sudden changes in luminance levels owing to a defect in the photoreceptor deactivation mechanism within the phototransduction cascades. Homozygous mutations in either the regulator G-protein signaling 9 (RGS9) or RGS9 anchor protein (R9AP) gene that encode the photoreceptor GTPase accelerating protein and its anchor protein, respectively, have been identified in patients with bradyopsia.2 We report a case of bradyopsia in an Asian man with characteristic electrophysiological and genetic findings. This study was approved by the institutional review board of the Singapore Eye Research Institute.
Cheng JYC, Luu CD, Yong VHK, Mathur R, Aung T, Vithana EN. Bradyopsia in an Asian Man. Arch Ophthalmol. 2007;125(8):1138-1140. doi:10.1001/archopht.125.8.1138