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Schlagwörter:
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Zusammenfassung:
Purpose/Introduction: Arterial Spin Labeling (ASL) has become a valuable tool to quantify perfusion in gray matter. However, quantitatively and accurately measuring blood flow in the much less perfused white matter has so
far not been possible. This is due to the low perfusion signal, the long transit
times in white matter and the unavoidable partial volume effects that arise
when white matter pixels of a high-resolution perfusion image are added to
obtain the necessary sensitivity [1]. These problems can to a certain degree
be avoided by using a single voxel technique to quantify blood flow in a relatively
large, but well-defined region.
Subjects and Methods: The FAIRPRESS-technique [2] combines a FAIR
perfusion module with a single voxel PRESS localization. To avoid partial
volume effects, saturation pulses were added to suppress signal contributions
from outside the selected region. Arterial signal was suppressed by strong
bipolar gradients in all three dimensions. Distal and proximal volumes were
saturated to additionally suppress inflowing blood.
