Quantifying early haemodynamic treatment effects in carotid stenosis using arterial transit artifacts and spatial CoV on ASL-MRI

Motivation: There is little understanding of how arterial transit artefacts (ATA) on ASL-MRI, which indicate regions of haemodynamic compromise, change in patients with carotid artery stenosis following optimised medical therapy versus surgical revascularisation. Goal(s): To assess treatment effects using visually rated ATA severity and a spatial coefficient of variance before and after optimised medical therapy versus additional surgical revascularisation. Approach: We visually rated ATAs using an established four-point grading system and computed the spatial coefficient of variance in corresponding regions. Results: Both methods demonstrated only surgical revascularisation led to significant improvements in haemodynamics 1-month post-treatment, solely within the ipsilateral middle cerebral artery cortical territory. Impact: A robust method of quantifying early haemodynamic treatment effects could be used to identify who truly benefits from surgical revascularisation in the long-term. Future work will correlate these measures to long-term clinical outcomes.