Visual field constriction on vigabatrin.

(1) Vigabatrin carries a high risk of concentric visual field constriction, sometimes associated with a drop in visual acuity. The changes in the visual field appear to be irreversible. (2) Consequently, vigabatrin can be considered only as a last resort for infantile spasms refractory to steroid therapy and for partial epilepsy refractory to other anticonvulsants. (3) Patients treated with vigabatrin must have their visual fields monitored regularly.