CONGENITAL NYSTAGMUS SURGERY - QUANTITATIVE-EVALUATION OF THE EFFECTS

Nystagmus intensities at various gaze angles were studied preoperatively and postoperatively, using accurate ocular motility recordings, in 3 cases [children] of congential nystagmus. In addition to shifting the nystagmus null, the surgery broadened the null region and resulted in an overall reduction in nystagmus intensity at all gaze angles. Surgical rotation also resulted in improved visual acuity in all cases. The postoperative acuity at 0.degree. was better than the preoperative acuity at both 0.degree. and the patient''s preferred gaze angle (i.e., the preoperative null angle). This was true not only for the 2 patients who showed an improved preoperative acuity with their head turn but also for the patient whose preoperative acuity did not substantially improve with her preferred head turn. Eye movement recordings have made it possible to accurately determine the amount of surgery required and to predict acuity increases even when undetectable during the preoperative clinical examination.