Coutts SB, Moreau F, Asdaghi N, et al. - In this prospective, observational, international, multicenter cohort study involving 1,028 patients (mean [SD] age, 63.0 [11.6] years), researchers established the frequency of acute infarct defined by diffusion restriction detected on diffusion-weighted imaging (DWI) MRI scan (DWI positive). Between June 1, 2010, and October 31, 2016, patients were enrolled. In total, 139 patients (13.5%) had an acute stroke as defined by diffusion restriction identified on MRI scans (DWI positive). After undergoing a brain MRI, the final diagnosis was revised in 308 patients (30.0%). Outcomes revealed that there were 7 (0.7%) recurrent strokes at 1 year. Older age, male gender, motor or speech symptoms, ongoing symptoms at assessment, no prior identical symptomatic event, and abnormal results of the initial neurologic examination were factors linked to MRI evidence of stroke in multivariable modeling. This research proposed that patients with transient ischemic attack and symptoms traditionally deemed low risk carry a significant risk of acute stroke as described on a brain MRI scan by diffusion restriction (DWI positive). A definitive diagnosis requires early MRI.