Optic nerve dysfunction in familial dysautonomia.

We examined 12 patients with familial dysautonomia who had clear corneas to determine if there was any optic nerve involvement. The patients ranged in age from 6 to 34 years. Visual acuity ranged from 20/20 to 20/100. Nineteen eyes of 12 patients (79%) had abnormal (mean +/- 3 S.D.) pattern reversal visual-evoked potentials as compared to 50 control eyes (P100 = 98.8 msec; S.D., +/- 4.5 msec). P100 latency appeared to worsen with age. Exodeviation was present in seven patients (58%) and correlated with visual acuity and P100 latency. Ophthalmoscopic examination showed some degree of optic nerve pallor in all eyes.