Hypertensive brain stem encephalopathy: clinically silent massive edema of the pons.

Hypertensive encephalopathy is a medical emergency whose clinical manifestations are associated with bilateral parieto-occipital lesions. We describe a case of hypertensive brainstem encephalopathy in which high blood pressure was accompanied only by nuchal headaches of violent onset. T2-weighted magnetic resonance images showed hyperintensity and edema of the pons without any parietooccipital lesions, but with hyperintense lesions at the level of the basal nuclei, insula and temporal lobes. The lesions rapidly regressed once the hypertension had been controlled.