Hyperdeviation and static ocular counterroll in unilateral abducens nerve palsy.

Twenty-seven patients with unilateral sixth nerve palsy and ten normal subjects were studied. The range of ductions was examined and the degree of abduction defect was recorded. The amount of horizontal and vertical deviations was measured in nine diagnostic positions by the prism and cover test, Maddox rod and prism test, and magnetic scleral search coils. MRI with enhancement was performed for patients under 50 years of age and those with neurologic signs. CT with contrast was obtained in patients with ischemic risk factors and those over 50 years of age. If CT was normal, patients were followed at about 3 months. Those without improvement at 3 months and those with an abnormal CT were further investigated with MRI. We report here the primary deviations in our subjects; the results for secondary deviations were similar. ANOVA was used for statistical analysis.