Stroke, Vol 16, 92-101, Copyright © 1985 by American Heart Association
T Reich, H Rusinek, M Youdin and M Clagnaz
Distribution of cerebral blood flow was measured with an array of 200
ultra-pure germanium radiation detectors and 133-Xe by inhalation. The
array "sees" the head as a composite of different subvolumes and enables
measurement of the concentration history of tracer every 1-10 sec in each
subvolume simultaneously. Subvolume mean flows, (fm), and partition
coefficients, lambda m, are derived by compartmental analysis of tissue
concentration washout curves. Errors from "cross talk," scalp radiation,
"look through," and assumed partition coefficients are eliminated. Average
fm adjusted for 40 mm Hg PACO2 in 14 cortical subvolumes (7 right, 7 left)
of four normal 21-24 year old controls ranged from 50 to 60 ml/100 cc
tissue/min, and lambda m ranged from 0.97 to 1.14. Average fm and lambda m
in white matter was 24 ml/100 cc/min and 1.42 - 1.14 respectively. During
CO2 inhalation, right and left hemispheric fm increased 6.4% and 5.7%/mm Hg
respectively, whereas white matter fm increased 2.2% and 3.4% mm Hg
respectively. There was no systematic difference between front and back or
dominant vs non- dominant sides. Three 73-84 year old controls had reduced
fm and CO2 reactivity in all subvolumes, lambda m was in the same range as
in younger controls. Two patients with intracranial cerebrovascular disease
showed excellent localization of ischemic subvolumes. One patient with
asymptomatic unilateral 98% stenosis of the internal carotid artery had a
similar distribution of blood flow in both hemispheres.
ARTICLES
Cerebral distribution of 133-Xe and blood flow measured with high purity germanium