ExploreASL: image processing toolbox for multi-center arterial spin labeling population analyses

Arterial spin labeling (ASL) perfusion MRI1 is rapidly maturing as a research tool, potential future biomarker2 and pharmacological monitoring agent3 for many diseases including neurodegeneration. There is thus a growing need for standardization of ASL image processing and quality control (QC) for voxel-based (VBA) and region-of-interest (ROI)-based analyses. Here, we present ExploreASL, a non-commercial software package that aims to harmonize image processing for ASL perfusion images for single- and multi-center studies4, 5. In addition, ExploreASL combines key structural image processing tools from recent literature to differentiate perfusion from structural effects.
Initiated through the EU-funded COST-action "ASL In Dementia", ExploreASL is a collaborative framework of researchers and clinical investigators. It was already used to process ~4000 ASL images from all major MRI vendors and ASL sequences, and a large variety of patient populations. The ultimate goal is to combine data from a large number of studies and identify common and different perfusion patterns to enhance knowledge of ASL image analysis and of the role of perfusion and structural changes in neurodegenerative pathophysiology.