Effect of cross-sectional imaging on negative appendectomy and perforation rates in children.

PURPOSE: To compare negative appendectomy and perforation rates in children who underwent ultrasonography (US), computed tomography (CT), or no imaging before urgent appendectomy. MATERIALS AND METHODS: All children who underwent urgent appendectomy during a 4(1/2)-year period were identified in a surgical billing database. Pathology reports were coded as negative or as showing acute inflammation or perforation. Imaging up to 14 days before appendectomy or abscess drainage was noted, and imaging-based diagnoses were compared with pathologic findings. Patient age and sex were recorded. RESULTS: Two hundred ninety-nine children, 176 (59%) male and 123 (41%) female (mean age, 10.4 years; age range, 1--21 years), underwent urgent appendectomy. One hundred twenty-six (42%) underwent no imaging, 121 (41%) underwent US with or without CT, and 52 (17%) underwent CT only; 44 (15%) underwent both US and CT. There were significantly higher rates of appendectomy with normal pathologic findings ("negative appendectomy") in patients who underwent no imaging (14% [18 of 126]) or US (17% [20 of 121]) versus the rates in those who underwent CT only (2% [one of 52]) (P =.02 and P =.007, respectively). The negative appendectomy rate was 7% in 96 patients who underwent CT with or without prior US. The perforation rates were not significantly different. CONCLUSION: As compared with children who underwent no preoperative imaging and those who underwent US, children who underwent CT had a significantly lower negative appendectomy rate, without a significantly higher perforation rate.

Imaging evaluation of suspected appendicitis in a pediatric population: effectiveness of sonography versus CT.

OBJECTIVE: The purpose of this study was to compare the diagnostic accuracy of graded compression sonography with that of helical CT for the diagnosis of appendicitis in a pediatric and young adult population. SUBJECTS AND METHODS: Between June 1996 and April 1999, 386 pediatric and young adult patients with suspected appendicitis were examined using sonography, CT, or both: 233 underwent sonography only, 71 underwent CT only, and 82 underwent sonography and CT. All sonograms and CT scans were prospectively interpreted as showing positive or negative findings for appendicitis by one of six pediatric radiologists. CT and sonographic findings were correlated with surgical and histopathologic findings or findings at clinical follow-up. RESULTS: Helical CT had a significantly higher sensitivity (95% versus 78%, p = 0.009) and accuracy (94% versus 89%, p = 0.05) than graded compression sonography for the diagnosis of appendicitis in children, adolescents, and young adults. The specificity of both techniques was 93%. Twenty of 82 patients who underwent both sonography and CT had discordance between the findings of the two examinations. The CT results were correct in a significantly greater number of patients with discordant examinations (17/20 patients [85%]). CONCLUSION: Helical CT has a significantly higher sensitivity and accuracy than graded compression sonography for the diagnosis of appendicitis in a pediatric and young adult population, particularly in children more than 10 years old.

Evaluation of suspected appendicitis in children and young adults: helical CT.

PURPOSE: To evaluate the accuracy of helical computed tomography (CT) for the diagnosis of appendicitis in children and to assess the utility of CT in establishing alternative diagnoses. MATERIALS AND METHODS: The medical records of 154 children (median age, 12 years; age range, 1-20 years) who were suspected to have appendicitis and who underwent CT were reviewed. The gastrointestinal tract was opacified in 151 of 154 patients: Only orally administered contrast material was used in 126 patients; only rectally administered contrast material, in 21 patients; and both oral and rectal contrast material, in four patients. CT findings were correlated with surgical and histopathologic findings or with clinical follow-up findings. RESULTS: Sixty-four CT scans were interpreted as positive for appendicitis and included 58 true-positive and six false-positive scans. Ninety scans were interpreted as negative and included 87 true-negative and three false-negative scans. CT had a sensitivity of 95% and a specificity of 94% for the diagnosis of appendicitis. In addition, in 32 (34%) of 93 patients without appendicitis, an alternative diagnosis was established on the basis of CT findings. CONCLUSION: Helical CT is useful in a pediatric population to diagnose or exclude appendicitis and to establish an alternative diagnosis.