Visually evoked response (VER) in amblyopia: A diagnostic and prognostic indicator?

Abstract

A study comprising 15 cases of anisometropic amblyopia and 15 cases of strabismic amblyopia was undertaken to analyse the alterations in the visually evoked response (VER) in amblyopia. Ten normal cases were taken to standardize the technique. A Nicolet Clinical Averager CA100 was used to record the VER. A full ophthalmic check up including cycloplegic refraction, visual acuity recording and fixation pattern by visuscope was carried out in all the cases.In normal cases the amplitude and implicit time of VER showed no statistically significant difference between the two eyes. However, a wide inter-subject variability was observed. the maximum amplitude was seen with a check size of 60′. In amblyopic eyes (both strabismic and anisometropic) there was a significant reduction in the amplitude and a significant increase in the implicit time when compared to the normal fellow eye. A significant amplitude difference of more than 5 μV, as also a significant increase of implicit time (more than 10 msec) was notice...