Abstract:
:Quantification of cerebral blood flow using QUIPSSII pulsed arterial spin labeling requires that the QUIPSS saturation delay TI1 is shorter than the natural temporal bolus width. Yet the duration of the bolus of tagged spins entering the region of interest varies during vasoactive stimuli such as gaseous challenges or across subjects due to differences in blood velocity or vessel geometry. A new technique, bolus turbo sampling, to rapidly measure the duration of the inflowing bolus is presented. It allows to optimize the arterial spin labeling acquisition to ensure reliable quantification of perfusion while maximizing the arterial spin labeling signal by avoiding the use of unnecessarily short label durations. The average bolus width measured in the right and left middle cerebral artery territories using the bolus turbo sampling technique has a repeatability coefficient of 75 ms and correlates significantly with the TI1,max determined from a novel multi-TI1 protocol (R=0.65, P<0.05). The possibility to measure the bolus width under hypercapnia is demonstrated.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Villien M,Chipon E,Troprès I,Bouvier J,Cantin S,Chechin D,Le Bas JF,Krainik A,Warnking JMdoi
10.1002/mrm.24412subject
Has Abstractpub_date
2013-06-01 00:00:00pages
1677-82issue
6eissn
0740-3194issn
1522-2594journal_volume
69pub_type
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