The clinical role of noncontrast helical computed tomography in the diagnosis of acute appendicitis.

BACKGROUND

The accuracy of noncontrast helical computed tomography (CT) for appendicitis has recently been demonstrated. What is its clinical utility?

METHODS

This was a retrospective review of 443 consecutive community hospital patients evaluated for acute appendicitis over an 18-month period using limited pelvic CT scan or clinical acumen alone.

RESULTS

Appendicitis was pathologically proven in 158 patients. The negative appendectomy rate was 5.4%. The best radiological indicators for a positive CT for appendicitis were pericecal inflammation (88%) and appendicolith(57%). Appendiceal CT was found to have a 92% sensitivity, 99.6% specificity, and a 97.5% accuracy. There were 260 patients who had a negative CT; 243 of these were sent home. Alternative diagnoses were identified in 22% of patients.

CONCLUSIONS

The liberal use of noncontrast helical CT results in a low negative appendectomy rate and a high degree of confidence that a negative CT will allow patients to be sent home safely.