T2*-weighted MRI versus oxygen extraction fraction PET in acute stroke.
BACKGROUND
Mapping high oxygen extraction fraction (OEF) in acute stroke is of considerable interest to depict the at-risk tissue. Being sensitive to deoxyhemoglobin, T2*-weighted MRI has been suggested as a potential marker of high OEF.


METHODS
We compared T2*-weighted images from pre-contrast arrival perfusion scans against quantitative positron emission tomography in 5 patients studied 7-21 h after onset of carotid territory stroke. OEF and T2* signal were obtained in the voxels with significantly high OEF.


RESULTS
All patients showed increased OEF. No significant relationship between OEF and T2*-weighted signal was found either within or between subjects.


CONCLUSIONS
We found no indication that T2*-weighted MRI in the way implemented in this investigation was sensitive to high OEF in acute stroke.
Donswijk
M L
ML
Stroke Research Group, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.
Jones
P S
PS
Guadagno
J V
JV
Carpenter
T A
TA
Moustafa
R R
RR
Fryer
T D
TD
Aigbirhio
F I
FI
Warburton
E A
EA
Baron
J C
JC
D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000473:pathology; D002340:Carotid Artery Diseases / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D049268:Positron-Emission Tomography; D020521:Stroke / Q000000981:diagnostic imaging* / Q000473:pathology*; D017585:Ultrasonography, Doppler, Transcranial
D010100:Oxygen