Abstract:
:Perfusion imaging by arterial spin labeling (ASL) can be highly sensitive to the transit time from the labeling site to the tissue. We report the results of a study designed to separate the transit time and perfusion contributions to activation in ASL images accompanying motor and visual stimulation. Fractional transit time decreases were found to be comparable to fractional perfusion increases and the transit time change was found to be the greatest contributor to ASL signal change in ASL sequences without delayed acquisition. The implications for activation imaging with ASL and the arterial control of flow are discussed.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Gonzalez-At JB,Alsop DC,Detre JAdoi
10.1002/(sici)1522-2594(200005)43:5<739::aid-mrm17subject
Has Abstractpub_date
2000-05-01 00:00:00pages
739-46issue
5eissn
0740-3194issn
1522-2594pii
10.1002/(SICI)1522-2594(200005)43:5<739::AID-MRM17journal_volume
43pub_type
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