[EEG findings in moyamoya disease in children--with special reference to the genesis of re-build up].

EEG findings in Moyamoya diseases in children are characterized by build up during hyperventilation and re-build up after hyperventilation. We examined EEG, tcPO2, tcPCO2 and respiratory curves during and after hyperventilation in 10 cases of typical Moyamoya disease in children. In all of the cases, tcPCO2 decreased gradually by hyperventilation, and its level was about 50% of the pre-hyperventilation level at the end of hyperventilation. It took about five minutes for the tcPCO2 level to return to the pre-hyperventilation level. On the other hand, tcPO2 was increased by hyperventilation. However, it decreased down to 50% of the pre-hyperventilation level within a few minutes after hyperventilation because of the following decrease in the respiratory rate, and it took 5 to 10 minutes to return to the pre-hyperventilation level. Sequential changes in tcPCO2 and tcPO2 showed good correlation with the biphasic change in EEG by hyperventilation in children with Moyamoya disease. The decrease in tcPO2 after hyperventilation seemed in particular to play an important role in the appearance of re-build up. We also examined tcPO2 and tcPO2 during and after hyperventilation in 9 cases of normal children. Sequential changes in tcPCO2, tcPO2 and the respiratory rate were the same as those in children with Moyamoya disease, but re-build up was not observed. In 4 cases of Moyamoya disease we examined the sequential changes in EEG, tcPCO2, tcPO2 and the respiratory rate under the inhalation of 100% O2 and 8% CO2 air.(ABSTRACT TRUNCATED AT 250 WORDS)