An evaluation of night vision mobility aids.

Two night vision aids are commercially available to help individuals who have diseases that cause night blindness. The ITT Night Vision Aid (NVA) is a light amplification device; the Wide Angle Mobility Light (WAML) is a wide beam flashlight. The effectiveness of both instruments in helping night-blind, field-restricted subjects to walk a course of residential streets at night was tested. WAML users were also surveyed to determine the usage, applications, and reliability of the device. We found that the WAML significantly reduced error rates and was preferred by most subjects; it was reported to be used regularly by individuals who owned it. The NVA did not significantly improve error scores, and was not effective as an ambulatory night mobility aid for most patients.