Whole Brain Quantification of Arterial Transit Time & Perfusion using Multi-Slice Pseudo-Continuous Arterial Spin Labelling

Wayne Lee¹, Rafal Janik², Bojana Stefanovic^2,3, John G. Sled^1,3

Whole brain quantitative imaging of cerebral perfusion and transit time provides a means to assess and characterize neurodegeneration. Robust estimation of perfusion and transit time by arterial spin labelling requires adequate sampling of the labelled spins in the tissue preceding the difference signal peak. However, even with rapidly acquired slices, the top third of the brain may not be sampled before the signal peak, too late for estimation of tA and having lower SNR. To address the issue of poor time-delay sampling of distal slices in traditional multi-slice acquisitions, we propose a novel slice ordering approach to multi-slice pseudo-continuous ASL. This Round Robin approach ensures that all slices are equally acquired across the same range of delays, enabling reliable model fits for a wide range of transit times throughout the brain.