Visual field loss in young children and mentally handicapped adolescents receiving vigabatrin

PURPOSE: In adult patients and in children of school age who have been treated with vigabatrin (VGB), persistent visual field defects have been reported as a side effect. To date, it is unknown to what extent VGB causes visual field loss in young children and mentally handicapped adolescents who cannot be tested with conventional perimetric METHODS: The purpose of the present study was to investigate VGB-induced visual field loss in these patients by using a noncommercial arc perimeter and a forced-choice, preferential-looking method. The visual field size was measured in 30 patients aged 1 to 15 years who had epilepsy and who were treated with VGB. The visual field of these patients was compared to the visual field of 70 control subjects. RESULTS: In eight (27%) patients who had been treated with VGB, the visual field was constricted compared with the visual field of the children belonging to the control group. CONCLUSIONS: Arc perimetry shows that mentally handicapped patients and children younger than 6 years treated with VGB have visual field loss compared with the loss reported in adult patients receiving VGB.