Binocular versus monocular acuity in a patient with latent nystagmus.

This is a case of latent nystagmus with a significant improvement in acuity with both eyes open rather than with either eye alone. If this patient's visual acuity was tested only O.D. alone and O.S. alone, the best visual acuity obtainable would have been 20/60. This might have had serious implications for A.F.'s work since a minimum visual acuity of 20/40 is needed to keep a driver's license in New York State. Since binocular acuity was 20/20, I assured him that driving is safe.