Wouter Teeuwisse1, Christopher Collins2,
Ching Wang2, Qing Yang2, William Ma2, Nadine
Smith1, Matthias van Osch1, Andrew Webb1
1Radiology, Leiden University Medical
Center, Leiden, Netherlands; 2Radiology, Hershey Medical School,
Hershey, PA, United States
Although
pulsed arterial spin labelling should benefit from high fields in terms of
sensitivity and longer blood T1
values, there are significant challenges to its successful implementation.
One of the major difficulties is in using commercial volume transmit coils
for efficient arterial labelling due to the inherent B1 inhomogeneities
produced by a human subject at high field. This work presents a simulation
study, and confirmatory experimental results, which show that the use of
appropriately-positioned water-based dielectric pads can be used to increase
the labelling efficiency and improve the quality of ASL scans at 7 Tesla.