Paralysis of downgaze in two patients with clinical-radiologic correlation.

Selective downgaze paralysis was correlated with discrete bilateral lesions at the mesencephalic-diencephalic junction in a 9-year-old girl following severe pneumococcal meningitis, and in a 64-year-old man who suffered an embolic infarction. Magnetic resonance imaging demonstrated bilateral lesions in the region of the rostral interstitial nucleus of the medial longitudinal fasciculus. Clinical-radiologic correlation allowed identification of the likely vascular cause in both patients.