Prolonged Venous Transit on MRI As A Prognostic Biomarker in Acute Ischemic Stroke: A Feasibility Study

Prolonged venous transit (PVT) on CT perfusion is an established marker of poor collaterals and stroke severity; feasibility on MR perfusion (MRP) is uncertain. We evaluated feasibility and prognostic value of PVT on MRP in 59 patients with suspected acute ischemic stroke using a "straight-to-MRI" workflow. Board-certified neuroradiologists visually defined PVT as Tmax ≥10 s in the superior sagittal sinus and/or torcula. Pearson correlation tested associations between binary PVT and discharge NIHSS and 90-day modified Rankin Scale (mRS) in the full cohort and treated sub-cohort (IV thrombolysis and/or thrombectomy). PVT correlated with worse outcomes in the full cohort (NIHSS r=0.469, p=0.002; mRS r=0.387, p=0.02) and more strongly in treated patients (NIHSS r=0.678, p=0.005; mRS r=0.631, p=0.01). These findings demonstrate that PVT can be assessed on MRP and is a potentially promising post-revascularization prognostic biomarker aligning with CTP-based physiology; larger studies are needed.