Visual defects associated with vigabatrin: a study of epileptic argentine patients

Abstract

Objective: The aim of the present study was to assess visual alterations in a population of Argentine patients treated with the antiepileptic drug vigabatrin. Methods: Twenty patients receiving vigabatrin and 15 patients receiving carbamazepine were examined with automated perimetry using a Humphrey 120-point full screening strategy. In addition, scotopic flash electroretinograms were performed. Results: Of 20 patients treated with vigabatrin, two were unable to cooperate with testing. Of the remaining 18 patients, all but two showed at least one non-detected point inside the central 40° of the visual field of each eye. Of the 15 carbamazepine-treated patients, three were unable to perform the study. None of the remaining 12 patients showed visual field defects. Both a- and b-wave amplitudes of the scotopic electroretinogram were significantly reduced in 12 patients receiving vigabatrin.The aim of the present study was to assess visual alterations in a population of Argentine patients treated with the antiepileptic drug vigabatrin. Methods: Twenty patients receiving vigabatrin and 15 patients receiving carbamazepine were examined with automated perimetry using a Humphrey 120-point full screening strategy. In addition, scotopic flash electroretinograms were performed. Results: Of 20 patients treated with vigabatrin, two were unable to cooperate with testing. Of the remaining 18 patients, all but two showed at least one non-detected point inside the central 40° of the visual field of each eye. Of the 15 carbamazepine-treated patients, three were unable to perform the study. None of the remaining 12 patients showed visual field defects. Both a- and b-wave amplitudes of the scotopic electroretinogram were significantly reduced in 12 patients receiving vigabatrin.Methods: Twenty patients receiving vigabatrin and 15 patients receiving carbamazepine were examined with automated perimetry using a Humphrey 120-point full screening strategy. In addition, scotopic flash electroretinograms were performed. Results: Of 20 patients treated with vigabatrin, two were unable to cooperate with testing. Of the remaining 18 patients, all but two showed at least one non-detected point inside the central 40° of the visual field of each eye. Of the 15 carbamazepine-treated patients, three were unable to perform the study. None of the remaining 12 patients showed visual field defects. Both a- and b-wave amplitudes of the scotopic electroretinogram were significantly reduced in 12 patients receiving vigabatrin.Results: Of 20 patients treated with vigabatrin, two were unable to cooperate with testing. Of the remaining 18 patients, all but two showed at least one non-detected point inside the central 40° of the visual field of each eye. Of the 15 carbamazepine-treated patients, three were unable to perform the study. None of the remaining 12 patients showed visual field defects. Both a- and b-wave amplitudes of the scotopic electroretinogram were significantly reduced in 12 patients receiving vigabatrin. Conclusions: Visual field defects among patients on vigabatrin therapy may occur with a higher frequency than previously recognized. The Humphrey 120-points full field screening test and electroretinography are useful tools to assess the visual dysfunction associated with vigabatrin.Visual field defects among patients on vigabatrin therapy may occur with a higher frequency than previously recognized. The Humphrey 120-points full field screening test and electroretinography are useful tools to assess the visual dysfunction associated with vigabatrin.

Objectif: Le but de cette étude était d’évaluer les changements visuels chez un groupe de patients argentins traités par le vigabatrin, un médicament anti-épileptique. Méthodes: Vingt patients recevant du vigabatrin et 15 patients recevant de la carbamazépine ont subi une périmétrie de dépistage plein écran de 120 points au moyen de l’appareil automatisé Humphrey. De plus, des électrorétinogrammes au flash scotopique ont été effectués. Résultats: L’étude n’a pu être réalisée chez deux des 20 patients traités par le vigabatrin à cause de leur manque de coopération. Chez les 18 autres patients, tous sauf deux avaient au moins un point non détecté au champ visuel central de 40o de chaque œil. Trois des 15 patients recevant de la carbamazépine n’ont pu compléter l’étude. Aucun des 12 autres patients n’avait de déficit au niveau des champs visuels. L’amplitude des ondes a et b de l’électrorétinogramme scotopique était significativement diminuée chez 12 patients recevant le vigabatrin. Conclusions: Des anomalies du champ visuel sont peut-être plus fréquentes qu’on ne l’estimait chez les patients recevant du vigabatrin. La périmétrie automatisée Humphrey plein écran de 120 points et l’électrorétinographie sont des méthodes utiles pour évaluer la dysfonction visuelle associée au vigabatrin.