Differentiating Brain Metastases Recurrence from Treatment-Induced Changes Using Velocity-Selective ASL: Initial Experience

Motivation: Brain metastases (BM) have increased frequency of treatment-related changes difficult to distinguish from progressive disease. To date, there are no studies evaluating arterial spin labeling (ASL) for BM patients during post-therapy follow-up. Goal(s): To evaluate the feasibility of velocity-selective ASL (VSASL) derived cerebral blood flow (CBF) mapping in differentiating metastases recurrence from treatment-induced changes. Approach: VSASL was applied to 9 BM patients, and compared with pseudo-continuous ASL (PCASL), dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI), and pathologic confirmation for some patients. Results: VSASL is clinically feasible and more comparable with DSC-PWI than PCASL in patients with treated BM at suspicion of tumor progression. Impact: This study showed that velocity-selective arterial spin labeling has the potential to offer a non-invasive alternative to dynamic susceptibility contrast perfusion-weighted imaging in differentiating tumor recurrence from treatment-induced changes among patients with brain metastases.