Macrovascular contamination may confound partial volume correction in ASL-derived CBF maps in patients with cerebrovascular disease

Motivation: Multi-delay arterial spin labeling (MD-ASL) can mitigate issues from delayed arterial transit times and secondary flow; however, partial volume correction (PVC) in the presence of macrovascular contamination may lead to overestimated cerebral blood flow (CBF) values. Goal(s): Evaluate the impact of macrovascular correction on CBF values using two common PVC methods. Approach: MD-ASL data from 20 Moyamoya patients was acquired using MRI and corrected for PVC, with and without macrovascular correction. Method agreement and potential differences were analyzed using Bland-Altman plots and paired t-tests (p<0.05). Results: Macrovascular correction paired with Bayesian PVC may overestimate CBF values compared to linear regression-based PVC methods. Impact: The choice of macrovascular correction method can negatively impact CBF estimates, depending on the PVC approach used. Linear regression PVC demonstrated greater precision, both with and without macrovascular correction, compared to the Bayesian method