Diagnostic accuracy of magnetic resonance imaging: A prospective evaluation of patients with suspected appendicitis (Diamond)

Purpose: To show the effect of standard magnetic resonance imaging (MRI) in patients with suspected appendicitis on negative laparotomy and perforation rate. Moreover, the economic impact on hospital resources was evaluated. Materials and Methods: In all, 52 patients (21 female; mean age 44.7 years) were prospectively included in this Institutional Review Board (IRB)-approved study. Abdominal MRI including coronal inversion recovery, axial T2weighted, and contrast-enhanced axial T1-weighted sequences was performed. MRI results were compared to final clinical outcome determined by follow-up or histopathology. Change of treatment was evaluated according to the final clinical outcome. Economic impact was evaluated by comparing the costs of MRI to the savings due to a change in treatment after MRI. Negative laparotomy and perforation rate as well as sensitivity and specificity were derived. Results: Negative laparotomy and perforation rate were 0% (0/52) and 8% (1/13). Sensitivity and specificity for detecting acute appendicitis were 85% (11/13) and 97% (38/39). In 40% of patients therapy changed due to the MRI. The overall effect on the use of hospital resources was a net saving of (sic) 2335. Conclusion: Abdominal MRI in the evaluation of patients with suspected appendicitis and equivocal clinical findings is safe, reliable, and cost-effective. It should be considered an important alternative to computed tomography.