PENDULAR NYSTAGMUS IN PATIENTS WITH PEROXISOMAL ASSEMBLY DISORDER

Background: Pendular nystagmus commonly occurs in congenital and acqui red disorders of myelin. Objective: To characterize the nystagmus in 3 siblings with an infantile form of an autosomal recessive peroxisomal assembly disorder causing leukodystrophy. Design: We examined visual function and measured eye movements using infrared oculography. We not ed changes in eye speed and frequency before and after the administrat ion of gabapentin to 1 patient. Results: All 3 siblings showed optic a trophy and pendular nystagmus that was predominantly horizontal, at a frequency of 3 to 6 Hz, with phase shifts of 45 degrees to 80 degrees between the oscillations of each eye. Gabapentin administered to 1 chi ld caused a modest improvement of vision and the reduction of the velo city and frequency of oscillations in the eye with worse nystagmus. Co nclusion: The pendular nystagmus in these patients was due to their le ukodystrophy and may have a similar pathogenesis to the oscillations s een in other disorders affecting central myelin.