Author:
Meyer J S,Hayman L A,Amano T,Nakajima S,Shaw T,Lauzon P,Derman S,Karacan I,Harati Y
Abstract
Non-invasive methods are described for estimating local cerebral blood flows (LCBF) and partition coefficients (L lambda) during inhalation of 35% stable xenon gas (Xes) in oxygen during CT scanning. After denitrogenation by 100% oxygen breathing, 35% Xes is breathed for 7-8 minutes to minimize subanesthetic effects. Mean changes in brain Hounsfield units extrapolated to 15 minutes were 7.7 units for white matter and 5.3 units for gray matter. They were measured from volumes 80 cubic mm (10 mm2 area x 8 mm), or larger with an EMI 1010 scanner at 1 minute intervals. These data were used for computing LCBFs and L lambdas. Irradiation measured at the center of brain slices was 1 rad per minute. To calculate L lambdas about 6 exposures are necessary, thereafter, each 1 minute scan provides LCBF measurements for 2 adjacent 8 mm slices. Reproducibility for LCBF was r = 0.85 (P less 0.001). Mean L lambdas were 0.86 +/- 0.08 for gray and 1.34 +/- 0.10 for white matter. Normative mean flows (mls/100 g brain/min) were: basal ganglia = 79.6 +/- 9.3, cortex = 82.3 +/- 8.5, white matter = 29.2 +/- 5.9, midbrain tegmentum = 94.3 +/- 14.8, cerebellar cortex = 80.1 +/- 10.9, dorsal pons = 89.3 +/- 4.7, brachium pontis = 35.0 +/- 4.2. Subject finger exercises produced increases of LCBF in contralateral pre-central and post-central gyri. Eye closure decreased flow values limited to the visual system. Gray matter flow values diffusely decreased in non-REM sleep but increased above normal in REM sleep. Cerebral infarction and hemorrhage resulted in zones of zero flow with borders having reduced lambdas and low flows attributed to edema.
Publisher
Ovid Technologies (Wolters Kluwer Health)
Subject
Advanced and Specialised Nursing,Cardiology and Cardiovascular Medicine,Clinical Neurology
Reference34 articles.
1. Regional Cerebral Blood Flow Estimated by133Xenon Inhalation
2. Obrist WD Wang HS: Comparison of "*Xe inhalation and I.V. injection in regional CBF studies. In Cerebral Vascular Diseases 2 10th WFN Salzburg Conference on Cerebrovascular Disease. Amsterdam Excerpta Medica International Congress Series in press 1981
3. Cerebral Complications Following Measurements of Regional Cerebral Blood Flow (rCBF) With the lntra-arterial
133
Xenon Injection Method
4. Methodological shortcomings of the;Eichling JO;Xe inhalation technique of measuring rCBF. Acta Neurologica Scand,1977
5. Two Methods for Calculating Regional Cerebral Blood Flow from Emission Computed Tomography of Inert Gas Concentrations
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