Sensitivity Function to Contrast in Anisometropic and Strabismic Amblyopia

Overview

The sensitivity function to contrast was assessed by means of a distance tableVCTS 6500 in children aged 5-11 years with monolateral anisometropic (48) orstrabismic (13) amblyopia before the onset and after five weeks intense pleoptictreatment. The control group was formed by 41 eyes of 30 children with a centralvisual acuity of 1.0. With regard to vision the anisometropic amblyopias weredivided into two groups, the criterion of visual acuity being 0.25. The resultsproved a statistically significant decline of sensitivity to contrast in all spatialfrequencies not only in both types of amplyopia but also in the other „healthy“eye of these patients. On comparison of the sensitivity to contrast in groups withan approximately equal mean vision (0.42-0.46) no statistically significant diffe-rence was found between anisometropic or strabismic amblyopia. Intensive ple-optic treatment (occlusion combined with CAM) led to a statistically significantimprovement of sensitivity to contrast in amblyopic as well as "healthy" non-am-blyopic eyes. In some instances even when the central visual acuity did notimprove. The authors recommend this method for a more accurate assessment ofvisual functions in children. It is however necessary to correct the normative datagiven by the manufacturer.

Key words:
sensitivity to contrast, anisometropia, strabism, amblyopia