Cobalt-55 positron emission tomography in symptomatic atherosclerotic carotid artery disease: borderzone versus territorial infarcts.
BACKGROUND
Borderzone as well as territorial infarcts can occur in severe atherosclerotic carotid artery disease. It remains controversial whether the borderzone distribution of infarcts is due to hypoperfusion or due to artery-to-artery embolism.


OBJECTIVE
The present study investigates whether cobalt-55 (55Co) positron emission tomography (PET) shows a different pattern of ischaemia according to the topography of the infarct in severe atherosclerotic carotid artery disease.


METHODS
Five patients with a cortical borderzone and seven with a territorial infarct, due to symptomatic carotid artery disease, were investigated with 55Co PET 3-6 months after stroke. Average 55Co counts in the infarct area, the adjacent cortical zone, the deep white matter and, contralateral cerebral cortex and white matter, were compared to the values in the cerebellum used as reference.


RESULTS
No differences in 55Co ratio were observed in the different regions of interest (ROIs) between patients with cortical borderzone and those with territorial infarcts. The 55Co uptake was similar or lower than the reference value for all ROIs in all individual patients.


CONCLUSIONS
In patients with borderzone as well as with territorial infarcts no evidence was found for subclinical ischaemic injury in or around the infarcts. These data do support the conclusion that cortical borderzone infarcts may not be due to ongoing chronic haemodynamic impairment, but by no means is this conclusive evidence.
De Reuck
Jacques
J
Department of Neurology, Ghent University Hospital, De Pintelaan 185, B-9000 Ghent, Belgium. jacques.dereuck@yucom.be
Paemeleire
Koen
K
Santens
Patrick
P
Strijckmans
Karel
K
Lemahieu
Ignace
I
D000328:Adult; D000368:Aged; D002545:Brain Ischemia / Q000000981:diagnostic imaging; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging*; D016893:Carotid Stenosis / Q000000981:diagnostic imaging*; D002531:Cerebellum / Q000098:blood supply*; D002540:Cerebral Cortex / Q000098:blood supply*; D002544:Cerebral Infarction / Q000000981:diagnostic imaging*; D002908:Chronic Disease; D003037:Cobalt Radioisotopes / Q000493:pharmacokinetics; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006801:Humans; D002537:Intracranial Arteriosclerosis / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012039:Regional Blood Flow / Q000502:physiology; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014055:Tomography, Emission-Computed
D003037:Cobalt Radioisotopes