Inflammatory Bowel Disease Diagnosed with US, MR, Scintigraphy, and CT: Meta-analysis of Prospective Studies

PURPOSE: To compare, by performing a meta-analysis, the accuracies of ultrasonography (US), magnetic resonance (MR) imaging, scintigraphy, computed tomography (CT), and positron emission tomography (PET) in the diagnosis of inflammatory bowel disease (IBD). MATERIALS AND METHODS: MEDLINE, EMBASE, CINAHL, and Cochrane databases were searched for studies on the accuracy of US, MR imaging, scintigraphy, CT, and PET, as compared with a predefined reference standard, in the diagnosis of IBD. Sensitivity and specificity estimates were calculated on per-patient and per-bowel-segment bases by using a bivariate random-effects model. RESULTS: Thirty-three studies, from a search that yielded 1406 articles, were included in the final analysis. Mean sensitivity estimates for the diagnosis of IBD on a per-patient basis were high and not significantly different among the imaging modalities (89.7%, 93.0%, 87.8%, and 84.3% for US, MR imaging, scintigraphy, and CT, respectively). Mean per-patient specificity estimates were 95.6% for US, 92.8% for MR imaging, 84.5% for scintigraphy, and 95.1% for CT; the only significant difference in values was that between scintigraphy and US (P = .009). Mean per-bowel-segment sensitivity estimates were lower: 73.5% for US, 70.4% for MR imaging, 77.3% for scintigraphy, and 67.4% for CT. Mean per-bowel-segment specificity estimates were 92.9% for US, 94.0% for MR imaging, 90.3% for scintigraphy, and 90.2% for CT. CT proved to be significantly less sensitive and specific compared with scintigraphy (P = .006) and MR imaging (P = .037) CONCLUSION: No significant differences in diagnostic accuracy among the imaging techniques were observed. Because patients with IBD often need frequent reevaluation of disease status, use of a diagnostic modality that does not involve the use of ionizing radiation is preferable.