Cerebral Hemodynamics in Cases with “Moyamoya” Disease

Abstract

Regional cerebral blood flow values (rCBF values) were measured during the resting state and during 5% CO2 inhalation by the Xe-133 clearance method in 11 cases with moyamoya disease and in 5 cases with unilateral moyamoya phenomenon. Electro-encephalography and cerebral angiography were simultaneously carried out. Examinations were performed in the chronic phase more than 3 months after the last subarachnoid hemorrhage or transient ischemic attack. Of the 11 cases with moyamoya disease, 3 were children under 20 years old. The 5 patients with unilateral moyamoya phenomenon were all adult. In the resting state, the rCBF values were normal in 5 and abnormally low in 3 out of the 8 adult cases, and were abnormally low in all 3 young cases of moyamoya disease. In the patients with unilateral moyamoya phenomenon, the rCBF values were normal in 3 and slight low in 2 cases. There were no obvious differences between the young and adult cases in their clinical features or in their electroencephalographic and cerebral angiographic findings. rCBF measurement during 5% CO2 inhalation were carried out in 9 cases with moyamoya disease and in 4 cases with unilateral moyamoya phenomenon. Increase in the rCBF values was noted in 3 out of 7 adult cases with moyamoya disease and in all 4 cases with unilateral moyamoya phenomenon, but was not observed in the 2 young cases with moyamoya disease. These results indicate that there are differences in the hemodynamic condition between cases with moyamoya disease and cases with unilateral moyamoya phenomenon. Furthermore, a discrepancy also exists between adult and young cases of moyamoya disease. The reason for these discrepancies can not be fully explained as yet. It is supposed that they are mainly due to differences of extent of the anastomotic process in small cortical branches.