Stroke, Vol 14, 356-362, Copyright © 1983 by American Heart Association
H Segawa, S Wakai, A Tamura, N Yoshimasu, O Nakamura and M Ohta
The present technique was developed to overcome some of the disadvantages
of measuring cerebral blood flow by radionuclide methods, such as poor
localization of flow values and errors that result if the brain is
pathological and local partition coefficients are altered. Serial CT
scanning in humans was carried out during and after inhalation of 50 to 70%
non-radioactive xenon. This diffusible gas with high atomic number enhanced
gray matter first by 19 +/- 4 Hounsfield Units (HU) and later white matter
by 24 +/- 4 HU. The regionality of flow values were cursored on CT pictures
with a high spatial resolution of 4 X 4 mm (64 pixels) or 0.16cm2 X 0.5cm.
In seven normal subjects, blood flow in gray matter was 82 +/- 11
ml/100gm/min and that in white matter 24 +/- 5ml/100gm/min. The partition
coefficient (lambda), which is not obtainable in vivo by radionuclide
scanning, was 0.9 +/- 0.1 for normal gray matter, 1.4 +/- 0.2 for normal
white matter. Reduced flow, 13% in gray matter and 46% in white matter, was
found in a large infarct secondary to complete occlusion of middle cerebral
artery. In edematous tissue, blood flow was not significantly impaired in
gray matter but was reduced to 29 to 54% in white matter. Local lambda
values were reduced to 0.6-0.9 in edematous tissue, and 0.3-0.7 in
infarction. This method appears to have several advantages over
conventional isotope methods of measuring cerebral blood flow and provides
useful clinical and research information.
ARTICLES
Computed tomographic measurement of local cerebral blood flow by xenon enhancement
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