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Abstract #2004

Observations on the Tagging Time and Velocity Cutoff Dependence in Velocity Selective ASL

Jia Guo1, Eric C. Wong2

1Bioengineering, University of California San Diego, La Jolla, CA, United States; 2Radiology and Psychiatry, University of California San Diego, La Jolla, CA, United States

We explore here the dependence of the velocity selective ASL signal on the tagging time and the velocity cutoff. We note that the peak of the ASL signal occurs at lower TI than expected, suggesting significant tissue water exchange or a shorter than expected bolus length. We also note oscillations in the inflow curve in some subjects that may provide information on the rate of deceleration in arteries.

Keywords

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