A 78Seconds Complete Brain MRI Examination in Ischemic Stroke: A Prospective Cohort Study.

Abstract

BackgroundFast 78‐second multicontrast echo‐planar MRI (EPIMix) has shown good diagnostic performance for detecting infarctions at a comprehensive stroke center, but its diagnostic performance has not been evaluated in a prospective study at a primary stroke center.PurposeTo prospectively determine whether EPIMix was noninferior in detecting ischemic lesions compared to routine clinical MRI.Study typeProspective cohort study.PopulationA total of 118 patients with acute MRI and symptoms of ischemic stroke.Field Strength and SequenceA 3 T. EPIMix (echo‐planar based: T1‐FLAIR, T2‐weighted, T2‐FLAIR, T2*, DWI) and routine clinical MRI sequences (T1‐weighted fast spin echo, T2‐weighted PROPELLER, T2‐weighted‐FLAIR fast spin echo, T2* gradient echo echo‐planar, and DWI spin echo echo‐planar).AssessmentThree radiologists, blinded for clinical information, assessed signs of ischemic lesions (DWI↑, ADC↓, and T2/T2‐FLAIR↑) on EPIMix and routine clinical MRI, with disagreements solved in consensus with a fourth reader to establish the reference standard.Statistical testsDiagnostic performance including sensitivity and specificity against the reference standard was evaluated. EPIMix sensitivity was tested for noninferiority compared to the reference standard using Nam's restricted maximum likelihood estimation (RMLE) Score. A P‐value < 0.05 was considered statistically significant.ResultsOf 118 patients (mean age 62 ± 16 years, 58% males), 25% (n = 30) had MRI signs of acute infarcts. EPIMix was noninferior with 97% (95% CI 83–100) sensitivity for reader 1, 100% (95% CI 88–100) sensitivity for reader 2, and 90% (95% CI 88–98) sensitivity for reader 3 vs. 93% (95% CI 78–99) sensitivity for readers 1 and 2 and 90% (95% CI 74–98) for reader 3 on routine clinical MRI. Specificity was 99% (95% CI 94–100) for reader 1, 100% (95% CI 96–100) for reader 2, and 98% (95% CI 92–100) for reader 3 on EPIMix vs. 100% (95% CI 96–100) for all readers on routine clinical MRI.ConclusionEPIMix was noninferior to routine clinical MRI for the diagnosis of acute ischemic stroke.Evidence Level2Technical EfficacyStage 2