Sixty adult patients with partial epilepsy who have been treated with vigabatrin for 7 months to 14 years as mono- or add-on therapy were examined with repeated kinetic Goldmann perimetries to evaluate the prevalence, risk factors, and long-term outcome of vigabatrin-associated visual field defects. A follow-up examination was performed after 4 to 38 months (mean, 15 +/- 7) in 55 patients, 29 of whom had discontinued vigabatrin therapy. Neither reversion nor progression in visual field constriction was observed.