Stroke, Vol 15, 80-90, Copyright © 1984 by American Heart Association
Stable xenon CT CBF measurements in prevalent cerebrovascular disorders (stroke)
JS Meyer, H Okayasu, H Tachibana and T Okabe
Local cerebral blood flow (LCBF) and local tissue: blood partition
coefficient (L lambda) values were measured for small volumes of gray or
white matter by CT CBF. Single compartment analysis was used but fitted to
infinity in normal volunteers aged between 20 to 100 years (N = 20).
Hemispheric LCBF and L lambda values were compared to those of 61 age
matched patients with transient ischemic attacks (TIAs, N = 10), reversible
ischemic neurologic deficits (RINDS, N = 10), acute and chronic cerebral
infarctions associated with emboli from atherosclerotic plaques or complete
occlusion of internal carotid or middle cerebral arteries (n = 9) or of
cardiac origin (N = 3), cerebral hemorrhage (N = 1), multi-infarct dementia
(MID) (N = 11) and arteriovenous malformations (AVM) (N = 17). In normal
aging, L lambda s were normal, but LCBF showed diffuse age-related
declines. Symptomatic cerebrovascular disease was characterized by
accentuation of age- related LCBF declines. TIAs with unilateral ICA
occlusion showed bilateral reductions of LCBF more evident in ischemic
hemispheres. TIAs due to fibrino-platelet emboli from ulcerated,
non-occlusive ICA plaques were characterized by transient unilateral,
localized LCBF reductions. All TIAs showed normal L lambda values. RINDS
showed both LCBF and L lambda reductions. Larger embolic infarctions of ICA
origin, whether acute or chronic, showed zones of zero flow with
surrounding reductions of LCBF and L lambda values. Recent cerebral
embolism of cardiac origin likewise exhibited zones of zero flow surrounded
by reduced LCBF and L lambda values; but in chronic stages LCBF and L
lambda values adjacent to zero flow zones were normal. MID was
characterized by patchy reductions of LCBF and L lambda values throughout
both hemispheres. Brain tissues surrounding AVM showed normal L lambda
values but LCBF values were reduced due to steal.