1Radiology, C.J.Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, ZH, Netherlands
Time encoded pseudo continuous arterial spin labeling (te-pCASL, a.k.a. Hadamard encoded pCASL) combined with a Look-Locker (LL) read out was applied to sample the tracer kinetics curve with high temporal resolution (50 ms). To improve LL performance a flip angle sweep and a temporal shift of LL images in subsequent acquisitions were implemented. Perfusion signal curves in arteries and tissue were fitted and variants of perfusion modeling were evaluated. Measurement of tissue perfusion in the visual cortex demonstrated decreased arterial cerebral blood volume (aCBV) and arterial transit time (ATT) upon visual stimulation while cerebral blood flow (CBF) increased.