A Binocular Approach to Treating Amblyopia: Antisuppression Therapy

Purpose. We developed a binocular treatment for amblyopia based on antisuppression therapy. Methods. A novel procedure is outlined for measuring the extent to which the fixing eye suppresses the fellow amblyopic eye. We hypothesize that suppression renders a structurally binocular system, functionally monocular. Results. We demonstrate using three strabismic amblyopes that information can be combined normally between their eyes under viewing conditions where suppression is reduced. Also, we show that prolonged periods of viewing (under the artificial conditions of stimuli of different contrast in each eye) during which information from the two eyes is combined leads to a strengthening of binocular vision in such cases and eventual combination of binocular information under natural viewing conditions (stimuli of the same contrast in each eye). Concomitant improvement in monocular acuity of the amblyopic eye occurs with this reduction in suppression and strengthening of binocular fusion. Furthermore, in each of the three cases, stereoscopic function is established. Conclusions. This provides the basis for a new treatment of amblyopia, one that is purely binocular and aimed at reducing suppression as a first step. (Optom Vis Sci 2010; 87:697-704)