‘Laterally alternating’ skew deviation Mechanism and significance

Abstract

Laterally alternating skew deviation was discovered in three patients with central neurological lesions. In two, it was associated with other oculomotor disorders suggesting a medial mesencephalic lesion, and CT scan showed marked abnormalities of the third ventricle. The third patient had a tuberculous meningo-encephalitis with basal symptoms. The pathophysiological mechanisms of the vertical interocular divergence is discussed: it was probably related to a bilateral defect of superior recti and overaction of the inferior obliques and suggested a medial supranuclear dysfunction.

Key Words:

• brainstem
• mesencephalon
• skew deviation