Evaluation of optic nerve function by flicker adaptation in optic nerve diseases

Abstract

The time required for the fading of a full-field 30-Hz flick-ering stimulus was measured in 15 patients (18 eyes) with optic nerve diseases to evaluate optic nerve function. Eleven eyes of eight patients had optic neuritis, five eyes had autosomal dominant hereditary optic nerve atrophy (DOA), and two eyes had Leber's hereditary optic neu-ropathy (LHON). The results were correlated with visual acuities and critical flicker frequencies (CFF). The fading was not complete within 50 seconds in the eyes with DOA (Group A) or in normal subjects; con-versely, complete fading was experienced in the eyes with optic neuri-tis and with LHON (Group B). No significant differences in CFF and visual acuity were found between Groups A and B. We conclude that visual fatigue in optic neuritis and LHON can be observed easily by flicker adaptation, and that flicker adaptation can be used as an addi-tional test for evaluating optic nerve function.