Binocular Function of Intermittent Exotropia Before and After Surgery

Purpose: We examined the binocular function of intermittent exotropia before and after surgery, and studied the effect of the surgery and the factor that might be involved in its result.Materials and Methods: 402 intermittent exotropic patients, who underwent their first surgical correction for the strabismus at Teikyo University Hospital, were examined for retinal correspondence and stereo acuity before and after surgery.Results: 367 patients (91.3%) had already had good stereo acuity before surgery when their eyes were straight. Regarding retinal correspondence, though 192 patients (47.8%) were abnormal (dual) before surgery, 301 patients (74.9%) were normal after surgery. The eye deviation of 101 patients who could not get normal retinal correspondence after surgery was significantly larger than normal (P <.001), and 77.2% of them had also vertical strabismus which was mainly composed of dissociated vertical deviation.Conclusion: Normal binocular function could be recovered by surgical treatment in most intermittent exotropic patients. When patients could not get normal retinal correspondence after surgery, we supposed that dissociated vertical deviation might exert an important effect upon their binocular function.