[Cerebral circulation and oxygen metabolism in children's "moyamoya" diseases]

Regional (r) CBF, rOEF, rCMRO2, rCBV in five cases of "moyamoya" disease in children were studied with PET scan, using 15O steady-state methods. All cases showed ischemic symptoms such as TIA, RIND and minor stroke. Intervals from the latest ictus to PET ranged from 3 days to 3 years 6 months. Control data were obtained through PET studies in 8 normal volunteers. Physiological parameters described above, in cerebral gray matter, white matter and basal ganglia were calculated and were carefully compared with normal control. Apparently low density area in X-ray CT were excluded from this analysis. Although rCBF showed a little bit higher value in all gray, white and basal ganglia, it was not statistically significant. rCBV of "moyamoya" disease significantly increased in gray, white and basal ganglia. The calculated value of CBF/CBV is considered to be an index of perfusion pressure and is the reversed value of transit time. This value was significantly decreased in "moyamoya" disease in every three region. Under the normal autoregulation, further decrease of perfusion pressure initiate increase of rOER and also decrease of rCBF. In spite of reduction of CBF/CBV, rOER was not significantly increased in every three region. Hence the cerebral circulation in children's "moyamoya" disease of ischemic type appears to be characterized by the mild decrease of perfusion pressure, dilated resistant vessels and prolonged circulation time.