Steady pulsed imaging and labeling scheme for noninvasive perfusion imaging.
OBJECTIVE
A steady pulsed imaging and labeling (SPIL) scheme is proposed to obtain high-resolution multislice perfusion images of mice brain using standard preclinical MRI equipment.


METHODS
The SPIL scheme repeats a pulsed arterial spin labeling (PASL) module together with a short mixing time to extend the temporal duration of the generated PASL bolus to the total experimental time. Multislice image acquisition takes place during the mixing times. The mixing time is also used for magnetization recovery following image acquisition. The new scheme is able to yield multislice perfusion images rapidly. The perfusion kinetic curve can be measured by a multipulsed imaging and labeling (MPIL) scheme, i.e., acquiring single-slice ASL signals before reaching steady-state in the SPIL sequence.


RESULTS
When applying the SPIL method to normal mice, and to mice with unilateral ischemia, high-resolution multislice (five slices) CBF images could be obtained in 8 min. Perfusion data from ischemic mice showed clear CBF reductions in ischemic regions. The SPIL method was also applied to postmortem mice, showing that the method is free from magnetization transfer confounds.


CONCLUSIONS
The new SPIL scheme provides for robust measurement of CBF with multislice imaging capability in small animals.
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.|F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.
Jiadi
J
Xu
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.|F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.
Qin
Q
Qin
Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Dan
D
Wu
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.|F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.
Jun
J
Hua
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Xiaolei
X
Song
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.|F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.
Michael T
MT
McMahon
Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Frances J
FJ
Northington
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Jiangyang
J
Zhang
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.|F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.
Peter C M
PC
van Zijl
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.|F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.
James J
JJ
Pekar
D000465:Algorithms; D000818:Animals; D001783:Blood Flow Velocity; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D002545:Brain Ischemia / Q000473:pathology / Q000503:physiopathology*; D002560:Cerebrovascular Circulation; D005260:Female; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D051379:Mice; D008807:Mice, Inbred BALB C; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D013113:Spin Labels
D013113:Spin Labels
arterial spin labeling (ASL); cerebral blood flow (CBF); multipulsed imaging and labeling (MPIL); perfusion; pulsed arterial spin labeling (PASL); steady pulsed imaging and labeling (SPIL); un-inverted flow-sensitive alternating inversion recovery (UNFAIR)