Diagnostic accuracy of neuroimaging in emergency department patients with acute vertigo or dizziness: A systematic review and meta‐analysis for the guidelines for reasonable and appropriate care in the emergency department

Background Patients presenting to the emergency department (ED) with acute vertigo or dizziness represent a diagnostic challenge. Neuroimaging has variable indications and yield. We aimed to conduct a systematic review and meta‐analysis of the diagnostic test accuracy of neuroimaging for patients presenting with acute vertigo or dizziness. Methods An electronic search was designed following patient–intervention–control–outcome (PICO) question—(P) adult patients with acute vertigo or dizziness presenting to the ED; (I) neuroimaging including computed tomography (CT), CT angiography (CTA), magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), and ultrasound (US); (C) MRI/clinical criterion standard; and (O) central causes (stroke, hemorrhage, tumor, others) versus peripheral causes of symptoms. Articles were assessed in duplicate. The Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines were followed. Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) was used to assess certainty of evidence in pooled estimates. Results We included studies that reported diagnostic test accuracy. From 6309 titles, 460 articles were retrieved, and 12 were included: noncontrast CT scan—six studies, 771 patients, pooled sensitivity 28.5% (95% confidence interval [CI] 14.4%–48.5%, moderate certainty) and specificity 98.9% (95% CI 93.4%–99.8%, moderate certainty); MRI—five studies, 943 patients, sensitivity 79.8% (95% CI 71.4%–86.2%, high certainty) and specificity 98.8% (95% CI 96.2%–100%, high certainty); CTA—one study, 153 patients, sensitivity 14.3% (95% CI 1.8%–42.8%) and specificity 97.7% (95% CI 93.8%–99.6%), CT had higher sensitivity than CTA (21.4% and 14.3%) for central etiology; MRA—one study, 24 patients, sensitivity 60.0% (95% CI 26.2%–87.8%) and specificity 92.9% (95% CI 66.1%–99.8%); US—three studies, 258 patients, sensitivity ranged from 30% to 53.6%, specificity from 94.9% to 100%. Conclusions Noncontrast CT has very low sensitivity and MRI will miss approximately one in five patients with stroke if imaging is obtained early after symptom onset. The evidence does not support neuroimaging as the only tool for ruling out stroke and other central causes in patients with acute dizziness or vertigo presenting to the ED.