Acute appendicitis in unenhanced spiral CT: Diagnostic luxury or benefit.

Purpose: To evaluate the diagnostic accuracy of thin collimated unenhanced spiral-CT in patients with clinically suspected acute appendicitis and to d etermine the impact: on patient management and overall costs. Method: Unenh anced focussed appendiceal spiral-CT was performed in 56 patients (23 women and 33 men) with clinically suspected acute appendicitis. Scans were obtai ned from the L4 level to the symphysis pubis using 5 mm collimation, 7.5 mm table feed (pitch 1.5) and 4 mm increment without i.v., oral, or rectal co ntrast material, prospective diagnoses based on CT findings were compared w ith surgical (and histopathological) results and clinical follow-up. The ef fect of spiral-CT on patient management and clinical ressources was assesse d. Results: 29 patients (10 women and 19 men) underwent appendectomy. Unenh anced spiral-CT was an accurate imaging technique for the initial examinati on of patients with suspected acute appendicitis with a sensitivity of 95.4 % and a specificity 100%, an accuracy of 98.2%, a positive predictive Value of 100%, and a negative predictive value of 97.1%. In 27 patients with no evidence of acute appendicitis, an alternative diagnosis could be made in 2 4 patients by unenhanced spiral-CT. Conclusion: Unenhanced spiral-CT is an accurate test to diagnose or to exclude acute appendicitis. Routine appendi ceal spiral-CT can improve medical care and reduce the overall costs for pa tients suspected of having acute appendicitis.