Measurement of visual acuity in latent nystagmus

A method is described for rapid and accurate assessment of visual acuity in patients with latent (occlusion) nystagmus. By using the duochrome slide of the American Optical Project-O-Chart and the green filter of the Worth red-green glasses, monocular visual acuity may be readily measured in patients with nystagmus brought out by monocular cover. The results obtained in seven patients are compared with standard opaque occlusion and occlusion with a +5.00 diopter lens.