Including contrast MR imaging can help physicians differentiate between perforated and non-perforated appendicitis.
Contrast-enhanced MRI can differentiate between perforated and non-perforated appendicitis among children, and may help guide management decisions in the work-up of pediatric appendicitis, according to a study published in Pediatric Radiology.
Researchers from New York-Presbyterian Hospital/Weill Cornell Medicine, in New York, performed a retrospective review to assess the performance of MRI in differentiating perforated from non-perforated pediatric appendicitis.
The review evaluated the records of 77 patients (mean age 12.2 years) with appendicitis. Twenty-two of the children had perforation. The researchers assessed: appendiceal restricted diffusion, wall defect, appendicolith, periappendiceal free fluid, remote free fluid, restricted diffusion within free fluid, abscess, peritoneal enhancement, ileocecal wall thickening, and ileus.
The results showed that the children who had perforations had a larger mean appendiceal diameter and mean number of MRI findings than the non-perforated group:
|Children with perforation||Children without perforation|
|Appendiceal diameter||12.3 mm||8.6 mm|
|Mean number of MRI findings||5.0||2.0|
Abscess, wall defect, and restricted diffusion within free fluid had the greatest specificity for perforation (1.00, 1.00, and 0.96, respectively) but low sensitivity (0.36, 0.25, and 0.32, respectively). The receiver operator characteristic curve for total number of MRI findings had an area under the curve of 0.92, with an optimal threshold of 3.5. A threshold of any four findings had the best ability to accurately discriminate between perforated and non-perforated cases, with a sensitivity of 82% and specificity of 85%.
The researchers concluded that contrast-enhanced MRI can differentiate perforated from non-perforated appendicitis and the presence of multiple findings increases diagnostic accuracy, with a threshold of any four findings optimally discriminating between perforated and non-perforated cases.