Assessment of baseline hemodynamic parameters within infarct progression areas in acute stroke patients using perfusion-weighted MRI.
BACKGROUND
The value of perfusion MRI for identifying the tissue at risk has been questioned. Our objective was to assess baseline perfusion-weighted imaging parameters within infarct progression areas.


METHODS
Patients with anterior circulation stroke without early reperfusion were included from a prospective MRI database. Sequential MRI examinations were performed on admission, 2-3 h (H2), 2-3 days (D2), and between 15 and 30 days after the initial MRI. Maps of baseline time-to-peak (TTP), mean transit time (MTT), cerebral blood volume (CBV), and cerebral blood flow (CBF) were calculated. Lesion extension areas were defined as pixels showing de novo lesions between each MRI and were generated by subtracting successive lesion masks: V(0), baseline diffusion-weighted imaging (DWI) lesion; V(1), lesion extension between baseline and H2 DWI; V(2), lesion extension from H2 to D2 DWI; and V(3), lesion extension from D2 DWI to final FLAIR. Repeated measures analysis was used to compare hemodynamic parameters within the baseline diffusion lesion and subsequent lesion extension areas.


RESULTS
Thirty-two patients were included. Baseline perfusion parameters were significantly more impaired within the acute DWI lesion compared to lesion extension areas (TTP, p < 0.0001; MTT, p < 0.0001; CBF p < 0.0001; CBV, p < 0.0001). A significant decrease in MTT (p = 0.01) and TTP (p = 0.01) was found within successive lesion growth areas.


CONCLUSIONS
A decreasing gradient of severity for TTP and MTT was observed within successive infarct growth areas.
Cerebrovascular Unit, Hôpital Neurologique Pierre Wertheimer, Hospices Civils de Lyon, 59 Bd Pinel, 69677, Bron, France.
Thomas
T
Ritzenthaler
Tae-Hee
TH
Cho
Marlène
M
Wiart
Julien
J
Berthiller
Leif
L
Østergaard
Marc
M
Hermier
Laurent
L
Derex
Yves
Y
Berthezène
Norbert
N
Nighoghossian
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D002544:Cerebral Infarction / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology*; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D020521:Stroke / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology*