The effect of
intravenous infusion of 10%
glycerol on polymorphic delta waves of EEG was investigated in 13 patients (15 studies) with
brain tumors in cerebral hemisphere. The delta waves were analyzed by two-dimensional EEG topography and power spectrum of delta waves (P(delta)) over the
tumor, adjacent, and distant regions in the same hemisphere to the
tumor, and ipsi- and contralateral hemispheres to the
tumor. The data focus of EEG topography was well corresponded to the
tumor and surrounding
brain edema which visualized by x-ray CT-scan. In the patient with
brain tumors with marked
brain edema (group A, 11 studies), EEG topography showed marked reduction of delta focus within 20 minutes from the end of
intravenous infusion of
glycerol, and returned to preinfusion distribution within 60 minutes. In patients with absent to minimum
brain edema (group B, 4 studies), delta focus showed the tendency to enlarge and returned to preinfusion state at 60 minutes after the end of
glycerol infusion. In patients of group A, P(delta) of ipsilateral hemisphere to
tumor decreased at the end of
glycerol infusion, and showing maximal reduction ratio (30%, p less than 0.01) at 20 minutes, re-increased there-after. In group B, P(delta) of ipsilateral hemisphere showed no definite changes after the
glycerol infusion. P(delta) of contralateral hemispheres in patients of both group A and B, showed similar reduction ratio and time course to those of ipsilateral hemisphere of group A.(ABSTRACT TRUNCATED AT 250 WORDS)