ASL Acquisition Principles

A variety of acquisition methods for arterial spin labeling (ASL) perfusion MRI exist, often with different names referring to broadly similar approaches. This chapter outlines the main flavors of ASL in common use, along with their strengths and weaknesses, before finally presenting the current consensus of the community on good acquisition parameters for general use. The chapter considers the choice of labeling (e.g. pseudo-continuous versus pulsed), readout (e.g. 2D versus 3D), the choice of post-label delay, and a number of other solutions to correct for artifacts such as arterial contamination. Avoiding extensive technical details, this chapter seeks to inform the ASL user when making choices about acquisition parameters for the use of ASL and also provides enough terminology to help a new user understand the key parameters that they need to know when presented with a new ASL dataset.