PURPOSE: The purpose of this study is to examine the applicability of a fast, contrast-free, 3-Tesla MRI protocol in children with suspected appendicitis and inconclusive sonographic findings.
MATERIALS AND METHODS: MRI studies of 18 pediatric patients with acute abdominal pain were prospectively collected and retrospectively evaluated. Fourteen out of 18 children were initially examined by ultrasound which was interpreted by a pediatric radiologist. Studies declared as inconclusive were referred to further evaluation by fast 3-Tesla MRI, all but one was performed within 24 hours after the ultrasound. One MRI was performed after 42 hours. Four of 18 patients were evaluated only by MRI. MRI protocol included three-plane single-shot breath-holding turbo spin-echo T2 weighted sequence with and without fat suppression, and a coronal balanced turbo field-echo cine, with administration of neither oral nor intravenous contrast agent. The efficacy of the MRI protocol was compared to a control group of seven pediatric patients with acute abdominal pain and equivocal sonogram who were further investigated by MRI with intravenous contrast agent.
RESULTS: The study group constituted of 18 MRI studies in 18 patients, 13 girls and 5 boys aged 8- 18 years, mean age 14.8 years. MRI scans ruled out appendicitis in 11/18 exams. Acute appendicitis was diagnosed in 5/18 studies. 2/18 studies were equivocal. Scan time was 6 to 30 minutes, median 15 minutes. In comparison, the control group included 8 MRI studies in 7 patients, 3 girls and 4 boys aged 9-16 years, mean 13.1 years. Acute appendicitis was diagnosed in 2/8 of control studies, ruled out in 4/8 and equivocal in 2/8. Scan time was 15 to 53 minutes, median 32 minutes (p value <0.0001).
CONCLUSION: Tailored breath-holding, fast 3-T MRI is a feasible alternative imaging modality for the diagnosis of acute appendicitis in pediatric population, especially in cases where sonographic findings are inconclusive. Administration of intravenous and oral contrast agent may be waivered for this subset of patients.
