The bright vessel sign on arterial spin labeling MRI for heralding and localizing large vessel occlusions

Abstract

Background and Purpose The significance of a bright vessel sign (BVS) at the site of a large vessel occlusion (LVO) on MR arterial spin labeling (ASL) sequence is not widely reported. We compared the utility of the ASL BVS to the gradient echo (GRE) susceptibility vessel sign (SVS) in heralding and localizing LVOs in a large cohort; most underwent digital subtraction angiography (DSA) and endovascular therapy for acute stroke. Methods A total of 171 patients with large hemispheric stroke symptoms had baseline and follow‐up MRIs with ASL, GRE, and MR angiogram (MRA). Scans were evaluated for (1) presence versus absence and (2) location of ASL BVS and GRE SVS. For patients who underwent DSA, data comparing presence and location of ASL BVS and GRE SVS to occlusions found on angiography, as well as resolution of the signs after successful recanalization, were also evaluated. Results Compared to MRA, the sensitivity of the ASL BVS for an LVO was .83, significantly better than .67 for GRE SVS (p = .001). Localization of vessel occlusion was correct 60.4% of the time by ASL compared to 64.4% by GRE (p = .502). For the 107 patients who underwent DSA, the sensitivity of ASL BVS was .80 compared to .64 for GRE SVS (p = .009). Localization of LVO found on DSA was correct 63.5% of the time by ASL BVS compared to 72.9% by GRE SVS (p = .251). Conclusion ASL BVS is significantly more sensitive than GRE SVS for identification of LVO on both MRA and DSA.

Predictive value of clot imaging in acute ischemic stroke: A systematic review of artificial intelligence and conventional studies

“…As evidence shows, the SVS sign is amply considered by conventional MRI studies as marker of the clot. Although the evidence is scarce, other sequences are being investigated as well: a recent study suggests that the bright vessel sign on arterial spin labeling (ASL BVS) is more sensitive for identification of LVO, when superposed with either MRA or DSA, compared to GRE SVS [76].…”