Regional Cerebral Blood Flow in Cases of Brain Tumor

The present series consists of 21 patients with brain tumors: 12 malignant gliomas, 4 oligo- dendro gliomas, 3 meningeomas and 2 metastases, studied by the133Xe-gamma-clearance rCBF method. In 16 patients at least 3 determinations of rCBF were performed: a) in the resting state, R; b) during hyperventilation, HV, and c) during hypertension, HT. Of the remaining 5 patients, 1 was studied only during R, while the other 4 were submitted either to HV or to HT additionally to the R study. The average age of this series of patients was 47 years, the youngest being 19 and the oldest 64. rCBF studies had to be performed under general anesthesia (N2O + O2, Engstrom respirator) in 5 instances in which the patients were uncooperative. MABP was continuously recorded through the internal carotid catheter. End- expiratory CO2was also monitored (and recorded) by means of an infrared analyser in selected cases. Arterial (and in some cases also cerebral venous) pH, pCO2 and pO2 were determined at least once for each Xenon injection.