Stereoacuity and fusional amplitude in foveal suppression

A retrospective study of 100 cases with suppression of one fovea was carried out to discover the relationship between the residual angle of strabismus (if present), the quality of stereopsis and fusional amplitudes. No direct linear relationship was present. However, the following conclusion could be reached. The greatest number of patients with one fovea suppressed who exhibited normal fusional amplitude have a residual esotropia between 5 and 10 prism dioptres. Stereoacuity, as well, tended to be superior in this group. From a practical standpoint, in patients with permanent suppression of one fovea, under binocular conditions, the eradication of any residual tropia, provided it is under 10 prism dioptres, will not improve binocular visual function.