Diagnostic performance of MRI for pregnant patients with clinically suspected appendicitis

PurposeTo evaluate the accuracy of magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis in pregnant patients and the value of additional diffusion-weighted MRI (DWI).MethodsA total of 125 pregnant patients with clinically suspected appendicitis who underwent 1.5T MRI were enrolled between May 2011 and January 2016. During this period, two radiologists prospectively predicted acute appendicitis on MRI during daily interpretation. We retrospectively reviewed clinical records, and radiological results were correlated with surgical pathology and clinical outcomes. We calculated the sensitivity, specificity, and accuracy of MRI for diagnosing acute appendicitis. We performed additional DWI between August 2014 and January 2016, and we calculated sensitivity, specificity, and accuracy of MRI with or without DWI.ResultsThe sensitivity, specificity, and accuracy of MRI for acute appendicitis were 100%, 95%, and 96%, respectively. The sensitivity, specificity, and accuracy of MRI without DWI (n=72) vs. with DWI (n=53) were 100%, 94.7%, and 95.8% versus 100%, 95%, and 96%, respectively.ConclusionsMRI has high accuracy for the diagnosis of acute appendicitis in pregnant patients. Therefore, MRI is recommended for use as a first-line diagnostic test for pregnant patients with clinically suspected appendicitis.