Comparison between MR-enterography and CT-enterography in patients with Crohn’s disease

Purpose: the aims of this study are: to evaluate diagnostic capabilities of Magnetic Resonance Imaging (MRI) and Multidetector Computed Tomography (MDCT) in Crohn’s disease (CD), to compare advantages and drawbacks of each technique in the assessment of CD. Materials and Methods: 40 consecutive patients with known or suspected CD underwent MRI and MDCT of the small bowel. MR and CT examinations were performed after oral administration of polyethylene-glycol solution. MRI protocol included T2-weighted SSFSE, FIESTA, Gd-enhanced T1-weighted LAVA sequences. MDCT scans were acquired 50 seconds after i.v. administration of 110-130 ml non ionic iodinated contrast medium. MR and CT scans were evaluated by two radiologists blinded to the gold standard represented by conventional enteroclysis, endoscopy and histology findings available in all patients. Results: disease prevalence was 77,5%. MRI showed accuracy of 92,5%, sensitivity of 93,5% (95% CI: 0,84-1,02), specificity of 88,9% (95% CI: 0,68-1,09), predictive positive value (PPV) of 96,7%, predictive negative value (NPV) of 80%. MDCT showed accuracy of 90%, sensitivity of 90,3% (95% CI 0,79-1), specificity of 88,9% (95% CI 0,68-1,09), PPV of 96,6%, NPV of 72,7%. MRI and MDCT evaluated luminal, parietal and extraintestinal findings. MR-fluoroscopy provided functional information about intestinal distension and motility. Conclusion: MRI and MDCT are useful methods for diagnosing CD. Lack of radiation exposure yields MRI the preferred method for follow-up of patients with CD.