Role of imaging in the diagnosis of acute appendicitis in children.

The aim of the study was to investigate the place of imaging in the diagnosis and treatment of acute appendicitis. The files of 2,427 children with suspected acute appendicitis were reviewed for clinical management and operative findings. The sample was divided into 3 groups at time of admission: (1) before diagnostic imaging was available in our department (1991-1994); (2) after the introduction of imaging studies on a random basis in equivocal cases (1995-1998); and (3) after a policy was formulated for ultrasound use in all equivocal cases followed by computed tomography if necessary (1999-2000). Results showed that the rate of misdiagnosis decreased from 13.2% in group 1 to 6.5% in group 2 and 6.1% in group 3. False-positive findings (normal appendix with positive scan) were noted in 16.7% of group 2 and 25% of group 3; false-negative findings (appendicitis at surgery with negative scan) in 23.8% and 9.5%, respectively. Computed tomography was performed in 8 children and prevented unnecessary surgery in 4 of them. We conclude that in equivocal cases of acute appendicitis, imaging studies performed by skilled operators can improve the accuracy of diagnosis, saving patients unnecessary surgery, and identifying other conditions that mimic appendicitis.