A Night Vision Device as an Aid for Patients With Retinitis Pigmentosa

Marked improvements in visual thresholds were observed in 14 patients with retinitis pigmentosa and in two patients with stationary night-blindness with myopia tested under scotopic conditions with a Generation I night vision device. All had visual acuities under scotopic conditions with the device that were comparable to their best visual acuities under photopic conditions. Psychophysical studies showed this device provided sufficient light amplification to allow cone function under dim scotopic conditions. Stimuli too dim to elicit a cone electroretinogram (ERG) without the device could elicit one with it. Results with this Generation I device as well as recent advances in microchannel technology (Generation II) suggest that a practical night vision device could be developed for patients with retinitis pigmentosa and other night-blinding conditions.