Capsular infarcts: location, size and etiology of pure motor hemiparesis, sensorimotor stroke and ataxic hemiparesis.

We investigated the types of syndrome, location, size and presumed causes of 72 patients with acute capsular lacunar infarction. Clinical syndromes were classified into pure motor hemiparesis (PM), sensorimotor stroke (SM) and ataxic hemiparesis (AH). Lesion sizes of AH were significantly smaller than those of PM (p < 0.01) or SM (p < 0.01). When the lesion volume was classified into two groups, > or = 1 ml and < 1 ml, the large volume group had more frequent cardioembolic sources than the small volume group (41% and 18% respectively, p < 0.05). In AH patients no cardioembolic sources could be detected. Significant carotid stenosis was found in only 4% of patients. Patients with anterior choroidal artery territory infarction had infrequent cardioembolic sources (7%). The results suggest that the lesion size varies with clinical syndrome and some etiological trends are seen in the volume and the location of lesions.