Diagnostic performance of CT findings in differentiation of perforated from nonperforated appendicitis

Objective: To assess performance of CT finding in differentiation of perforated from non-perforated appendicitis in Siriraj hospital, Bangkok, Thailand and evaluate accuracy of each finding by using multidetector row computer tomography (MDCT). Material and Method: Between June 2006 and May 2009, all adult patients (age more than 15 years) who had a diagnosis of acute appendicitis in Siriraj Hospital that was confirmed by pathology or surgical records and received a CT scan whole abdomen or lower abdomen with contrast administration before surgical or medical treatment were included in this study. The 48 consecutive CTs of whole or lower abdomen examinations were retrospectively reviewed by two radiologists. Sensitivity, specificity, and accuracy of CT compared with pathologic or surgical findings. Results: In 48 patients, 21 patients of non-perforated appendicitis and 27 patients of perforated appendicitis were enrolled. The CT findings of abscess, extraluminal appendicolith, and extraluminal air had the highest specificities for perforated appendicitis, 95.24%, 100%, 95.24%, respectively. The best accurate finding was defect in enhancing appendiceal wall. The CT findings of enlarged mesenteric lymph nodes at right lower quadrant region and defect in enhancing appendiceal wall had the highest sensitivities, 88.88% and 88.46%, respectively. Group 3 of combined specific findings had the best sensitivity (92.59%) and accuracy (83.3%). Conclusion: Multi-detector CT can help to differentiate perforated from non-perforated appendicitis.