[Cerebral blood flow reactivity to hyperventilation in children with spontaneous occlusion of the circle of willis (moyamoya disease)].

To elucidate the relationship between cerebral blood flow (CBF) after hyperventilation (HV) and the rebuild-up phenomenon on the encephaloelectrogram (EEG) in children with moyamoya disease, comparative study of CBF immediately after HV and CBF after administration of acetazolamide (Diamox) was examined. CBF was measured by means of single photon emission CT (SPECT) using the 133Xe inhalation method. The subjects were 11 children (21 hemispheres) with moyamoya disease who were divided into two groups as follows, 1) Bypass group; who underwent STA-MCA anastomosis with other synangiosis. 2) Non-Bypass group; who underwent only some synangiosis such as EDAS, EMAS, EMS. The summary of the results is shown below. Regional CBF (rCBF) after HV of the frontal lobes in the Non-Bypass group had an evident tendency to show low perfusion compared with CBF in other regions. The correlation between low perfusion area after HV, and areas where the increase of rCBF is less after administration of acetazolamide became clear. The strongest relation was observed between low perfusion after HV and re-build-up phenomenon on EEG. On the other hand, rCBF after HV of the frontal lobes in the Bypass group had, compared with other regions, no tendency to show low perfusion. From this study and our previous reports, it is assumed that there is some hemodynamic insufficiency in the frontal lobes of the Non-Bypass group. The reason why the reduction of rCBF was less after HV especially in the frontal lobes of the Bypass group is still unknown.(ABSTRACT TRUNCATED AT 250 WORDS)