Disorders of vertical optokinetic nystagmus in patients with ocular misalignment.

Purpose: To compare responses to vertical and horizontal optokinetic (OK) stimulation in patients with disorders of ocular alignment.

Methods: Using the magnetic search coil technique, we measured horizontal and vertical rotations of both eyes in six patients with strabismus since childhood and eight normal subjects. The OK stimulus subtended 72 degrees horizontally and 60 degrees vertically, consisted of black-and-white stripes with a spatial frequency of 0.