Lucila Argentina Rosines MD, Presenter: Nothing to Disclose

Daniel S. Chow MD, Abstract Co-Author: Nothing to Disclose

Firas Salem Ahmed MBChB,MPH, Abstract Co-Author: Nothing to Disclose

Brooke Sara Lampl DO, Abstract Co-Author: Nothing to Disclose

Carrie B. Ruzal-Shapiro MD, Abstract Co-Author: Nothing to Disclose

This study aims to determine the value of gadolinium enhanced magnetic resonance imaging (MRI) in children with acute appendicitis, and to determine which sequences are best at detecting acute appendicitis, thereby decreasing imaging time.

This was a retrospective analysis, between 7/2010 and 1/2011, examining MRI and hospital records for children (age 7-18) who visited the ER and were clinically suspected of having appendicitis. Images were reviewed by 6 radiologists who were blinded to the final diagnosis. Sequences performed included: axial/coronal balanced steady-state free precession (bSSFP), axial/coronal/sagittal T2-weighted, and axial/coronal T1-weighted post contrast. Each sequence was assessed independently and radiologists were asked to decide whether or not appendicitis was present on a five point scale.  Diagnostic performance between sequences were assessed by examining sensitivity, specificity, and by multireader, multicase receiver operating characteristic (ROC) method.

A total of 64 children clinically suspected of having appendicitis received MR imaging. Patients who underwent appendectomy numbered 17/64 of which 17/17 were consistent with appendicitis on pathology. Additionally, 1/64 patients had appendicitis treated medically. The sensitivities for the axial & coronal bSSFP, sagittal, axial & coronal T2, and axial & coronal T1 post contrast sequences were 66%, 40%, 58%, 77%, 68%, 73%, 80% respectively. The specificities for the axial & coronal bSSFP, sagittal, axial & coronal T2, and axial & coronal T1 post contrast sequences were 89%, 93%, 94%, 92%, 91%, 94%, 95% respectively. For ROC analysis, T1 post contrast images (AUC 0.923) performed significantly better than bSSFP sequences (AUC 0.808), with the average difference between the two modalities of 0.116 (95% CI: 0.060, 0.171). T2 images (AUC 0.893) also performed significantly better than bSSFP sequences, with the average difference between the two modalities of 0.0852 (95% CI: 0.029, 0.141). No significance difference was seen in performance between T1 post contrast and T2 images (95% CI: -0.025, 0.086).

Gadolinium enhanced and T2-weighted MR images are superior in diagnosing acute appendicitis in the ER pediatric population compared to bSSFP images.

The addition of gadolinium enhanced MRI in children with acute appendicitis, may increase the diagnositc accuracy of detecting appendicitis on MRI. 

Rosines, L, Chow, D, Ahmed, F, Lampl, B, Ruzal-Shapiro, C, Value of Gadolinium Enhanced Contrast Magnetic Resonance Imaging in Detecting Acute Appendicitis in the Pediatric Emergency Room Population.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12021394.html