The natural history of hemispheric and brainstem infarction in Rochester, Minnesota.

All cases of first episodes of brain infarction occurring in the population of Rochester, Minnesota, from 1960 through 1979 were categorized as hemispheric or brainstem (including cerebellar) on the basis of clinical criteria, autopsy evidence, and the results of computed tomography (from 1973 on). Hemispheric infarction was 5 times more frequent than infarction of the brainstem and/or cerebellum. The magnitude of the decline in incidence was the same in each group during the 20-year period of the study. Thirty-day case fatality was similar in each group, but patients with brainstem infarction had a better long-term survival. Functional outcome among survivors of brainstem infarction was also better, 35% having returned to independent living by 1 year after onset compared with 22% of survivors of hemispheric infarction. This may have been a consequence of the higher proportion of residual cognitive and sensory impairments present in survivors of hemispheric infarction.