Skip to main content

Diagnostic Accuracy of Portable Low- and Ultra-Low-Field MRI for Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

In brief

Portable low-field MRI finds 73% of acute strokes, misses one in four

A meta-analysis of nine studies (474 patients) showed portable low- and ultra-low-field MRI correctly identified about 73% of confirmed ischemic strokes, with a detection rate of roughly 88% overall, but roughly one in four small lesions were missed. The tool may aid bedside imaging when conventional MRI is unavailable, yet it cannot be relied on alone to rule out stroke.

Journal
AJNR. American journal of neuroradiology (Q1)
Published
16 July 2026
Study design
Systematic review / meta-analysis of RCTs
Evidence level
Level 1, High (CEBM 1a)
Authors
Mehmet Can Pence, Alperen Elek, Cem Bilgin, Sedat Giray Kandemirli, Hasan BaniHani, Ram Kadirvel, et al.
PMID
42463301
DOI
10.3174/ajnr.A9532

Why clinicians should know about it

Abstract

BACKGROUND: Portable low-field and ultra-low-field MRI enables bedside imaging, but its diagnostic performance for acute ischemic stroke (AIS) detection remains uncertain. PURPOSE: To evaluate the diagnostic performance of portable MRI for AIS detection. DATA SOURCES: Four databases were searched on February 2, 2026. STUDY SELECTION: Eligible studies enrolled adults with suspected or confirmed AIS undergoing portable MRI. Nine studies comprising 474 patients with AIS were included. DATA ANALYSIS: In studies with an appropriate reference standard, pooled sensitivity and specificity were synthesized using a bivariate random-effects model, and a hierarchical summary receiver operating characteristic curve was generated. Across all eligible AIS cohorts, the pooled lesion detection rate was estimated using a generalized linear mixed-effects model with random effects. DATA SYNTHESIS: In six comparative studies, the pooled sensitivity for AIS detection was 73.3% (95% CI, 65.4-80.0), corresponding to approximately one in four confirmed infarcts being missed, with missed lesions generally small or sub-centimetric. Pooled specificity was 79.3% (95% CI, 69.1-86.8), and the area under the curve was 0.818. The pooled AIS lesion detection rate was 87.65% (95% CI, 75.7-94.2). LIMITATIONS: There was substantial between-study heterogeneity (I2 = 74.2%). This estimate was interpreted as secondary and descriptive because it included case-only confirmed AIS cohorts. CONCLUSIONS: Portable low/ultra-low-field MRI showed moderate diagnostic performance for AIS detection in comparative studies and may serve as a bedside adjunct where conventional MRI is constrained. However, given the false-negative risk, portable MRI should not be relied upon as a stand-alone rule-out test for AIS when clinical suspicion persists.

Abstract as published, via PubMed.

View on PubMedFull text at the publisherOpen in the app

For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.