Cerebral blood flow and blood volume measured by magnetic resonance imaging bolus tracking after acute stroke in pigs: comparison with [(15)O]H(2)O positron emission tomography.
OBJECTIVE
Early and accurate assessments of cerebral ischemia allow therapy to be tailored to individual stroke patients. We examined the feasibility of using a novel method for measuring cerebral blood flow (CBF) of ischemic tissue based on MRI after middle cerebral artery occlusion (MCAO). Moreover, the regional correlations between CBF and cerebral blood volume (CBV) were investigated in the regions with acute ischemic stroke.


METHODS
CBF and CBV were measured before and after MCAO or reperfusion by positron emission tomography (PET) in 13 pigs. Just after the PET scans, CBF and CBV were measured by MR bolus tracking and were compared with results obtained by PET at 6 hours after permanent MCAO or reperfusion. The infarction was verified histologically.


RESULTS
The MR method yielded parametric CBF and CBV maps with tissue contrast in good agreement with parametric PET images, which demonstrated hypoperfused and hyperperfused areas after MCAO or reperfusion. Both MRI and PET technology showed that CBF values below 60% of the contralateral value induced a reduction of CBV, which committed the tissue to infarction.


CONCLUSIONS
The novel MR method provides accurate measurement of CBF and CBV in acute stroke and hence gives useful information for planning the appropriate therapeutic intervention.
PET-Center, Aarhus University Hospital, Denmark. sakoh@m.ehime-u.ac.jp
M
M
Sakoh
L
L
Røhl
C
C
Gyldensted
A
A
Gjedde
L
L
Ostergaard
D000208:Acute Disease; D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology*; D002545:Brain Ischemia / Q000175:diagnosis / Q000503:physiopathology*; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004195:Disease Models, Animal; D005240:Feasibility Studies; D005260:Female; D008279:Magnetic Resonance Imaging; D015588:Observer Variation; D010103:Oxygen Isotopes; D015203:Reproducibility of Results; D013552:Swine; D014055:Tomography, Emission-Computed
D010103:Oxygen Isotopes