Retinal blood flow and oxygen saturation were evaluated in patients with unilateral inner retinal degeneration secondary to neurogenic optic atrophy. Arteriovenous O2 saturation for temporal and nasal vascular segments of the affected eyes, evaluated by retinal vessel oximetry, was 12% +/- 9% higher than in the fellow eyes (seven patients). Blood flow in the temporal retinal arteries of the affected eyes, measured by the laser Doppler technique, was 48% +/- 20% lower than in the fellow eyes (four patients). The combination of these results indicated a 40% +/- 29% reduction in O2 delivery in the affected eyes (four patients), thereby quantifying the decrease in retinal metabolism that resulted from inner retinal degeneration.