Diagnostic value of 33 Hz steady-state visual evoked potentials in low-vision children.

Pattern-reversal visual evoked potentials elicited by patterns of 60' and 20' checks and 33 Hz steady-state flash visual evoked potentials were recorded in low-vision children (visual acuity less than 20/120) with optic atrophy (18 eyes), amblyopia (18 eyes), macular degeneration (7 eyes) and controls (24 eyes). Steady-state visual evoked potentials were non-recordable in 17 out of 18 eyes of optic atrophy patients and normal in other children. Abnormalities of pattern-reversal visual evoked potentials were similar in all groups of patients. 33 Hz steady-state flash visual evoked potentials are recommended for differential diagnosis of optic atrophy with other causes of low vision in children.