Recommendations for visual evaluations of patients treated with vigabatrin.

Although vigabatrin has been used for many years in Europe, this antiepileptic medication was approved for use in the USA only 1 year ago because of concerns for irreversible peripheral visual field loss that can result in functional visual disability. Visual function testing involves both subjective and objective techniques, some of which can be standardized across multiple centers. With these subjective and objectives issues as a reference, the current literature about the pathogenesis of vigabatrin visual toxicity is reviewed in order to develop a practical and reliable testing program for detecting peripheral visual field changes early in their course; thereby, hopefully limiting disabling visual field loss. Based upon the existing literature as well as the currently available data about the evaluation of visual function, an algorithm has been developed to serve as a starting point for clinicians to evaluate patients treated with vigabatrin for refractory epilepsy.