Ninety-six consecutive stroke patients were examined by sequential CT scans. Edema in the acute/subacute state and atrophy in the chronic state were evaluated by measuring a frontal horn index, septum-caudate distance and width of cortical sulci. In the acute state the degree of edema increased with increasing size of the infarct. Cerebral swelling was more marked and persisted for a longer period in patients having intracerebral hematomas than in patients with ischemic infarcts. Surprisingly, edema was present in the unaffected hemisphere as well. Development of atrophy was seen in the affected hemisphere in patients having large infarcts and intracerebral hematomas. Atrophy did not develop in the unaffected hemisphere.