Clinical studies on cerebral infarction

Hemorrhagic infarction (HI) is termed as the infarction in which a large part of the necrotic tissue is stippled with small hemorrhage. The pathogenetic mechanism of this disease still remains controversial. Cerebral infarction has long been divided into two subtypes-thrombosis and embolism-according to the pathogenetic mechanisms. Clinical studies were carried out in 31 cases of HI with cerebral thrombosis. CT findings of these cases were classified into five groups according to both size of low density area which indicates regions of infarction and distribution of arterial supply. The low density area of Type I-Type III were observed in the area of the middle cerebral artery. That of Type IV was observed in the area of the internal capsule and basal ganglia. That of Type V was observed in the area of the posterior cerebral artery. CT reveals two patterns of HI -pattern A and pattern B-. The CT finding of pattern A is appearance of high density area in the low density area. The CT finding of pattern B is appearance of iso density area in the low density area. rCBF was measured by 133Xe inhalation technique in 21 patients with CT type I, II and III. Thereafter, with regard to the various findings in CT, the clinical findings and CBF findings, a comparative study was carried out on these ten groups. From the results of present studies, it is concluded that sequential changes of CBF in cases with pattern A are different from those with pattern B, and that CBF measurement does not permit an estimation of a patient's chance for functionary recovery after a stroke in acute and subacute stage but permits estimation of functional outcome in chronic stage. (J.P.N.)