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.