Walsh & Hoyt: Ocular Motor Syndromes Caused by Lesions of the Superior Colliculus

Lesions restricted to the superior colliculi are rare in humans. One patient underwent removal of a cavernous angioma from the right superior colliculus. Following surgery, he had persistently impaired upward gaze, implying pretectal damage, but a full range of horizontal eye movements. Systematic testing of horizontal saccades demonstrated a paucity of spontaneous refixations contralateral to the side of the lesion. Saccades to the left occurred after a normal latency but were hypometric. These findings are similar to those seen after experimental ablation of the superior colliculi in monkeys. Pierrot-Deseilligny et al. reported a patient who had a hematoma largely restricted to the right superior colliculus. The patient showed defects in latency and accuracy for contralateral saccades and increased numbers of inappropriate saccades during the antisaccade task.