Comparison of FAIR perfusion kinetics with DSC-MRI and functional histology in a model of transient ischemia.
Flow-sensitive alternating inversion recovery (FAIR) is a noninvasive method for perfusion imaging. It has been shown that the FAIR signal may depend on hemodynamic parameters other than perfusion, the most important one being transit delays of labeled spins to the observed tissue. These parameters are expected to change with ischemia. The goal of this study was to assess the effect of these changes on the interpretation of FAIR results in the case of altered perfusion. This was investigated in a rat model of transient cerebral ischemia. It was shown that the ratio of FAIR signal in the infarct compared to the contralateral side was lower at short inflow times, which suggests that transit times affected the effective FAIR signal. The FAIR results were compared with those from functional histology and dynamic susceptibility contrast MRI, and the findings indicated that the altered kinetics of the FAIR signal were related to reduced and delayed inflow in the infarct region--not to a decrease in the number of functional vessels.
Schepers
Janneke
J
Department of Experimental In Vivo NMR, Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands.
Veldhuis
Wouter B
WB
Pauw
Robert-Jan
RJ
de Groot
Jan-Willem
JW
van Osch
Matthias J P
MJ
Nicolay
Klaas
K
van der Sanden
Boudewijn P J
BP
D000818:Animals; D002545:Brain Ischemia / Q000503:physiopathology*; D002560:Cerebrovascular Circulation; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344; D012039:Regional Blood Flow