Campbell, B. C.V. et al. (2019) Penumbral imaging and functional outcome in patients with anterior circulation ischaemic stroke treated with endovascular thrombectomy versus medical therapy: a meta-analysis of individual patient-level data.ABSTRACT Background: CT-perfusion (CTP) and MRI may assist patient selection for endovascular thrombectomy. We aimed to establish whether imaging assessments of ischaemic core and penumbra volumes were associated with functional outcomes and treatment effect.

"mismatch" between positive DWI and negative FLAIR allows the identification of patients that are highly likely to be within the 3-hour time window. Within the first 6 hours of stroke, the sensitivity of FLAIR sequences for acute ischemic lesions increases with time from symptom onset elapsing, approximating 100% after 3 to 6 hours.

Stroke MRI on admission predicts malignant course in severe MCA stroke with high positive and negative predictive value and may help in guiding treatment decisions, such as decompressive surgery. In a subset of patients with small initial DWI lesion volumes, repeated diagnostic tests are required.