BACKGROUND: Acute appendicitis is a common cause of hospital admission and emergency laparotomy among children and young adults. Although the diagnosis is clinical, the use of radiological imaging has emerged over the past decades. Its principal use is as a problem-solving tool in equivocal cases. Owing to the increased use of imaging in the last few years, the negative appendicectomy rate has dropped significantly. In this prospective observational study, we compared the diagnostic accuracy of Ultrasonography and Non-Contrast Computed Tomography.

METHOD: One hundred and eighteen patients with clinically suspected appendicitis followed a designed protocol. Patients underwent appendicectomy after a first performed positive ultrasonography or after a positive Non-Contrast Computed Tomography when Ultrasonography was equivocal or nonspecific. When any other diagnosis was apparent in either imaging modality which could explain the symptomatology in the patient, they were considered negative for acute appendicitis and treated accordingly.

RESULTS: The respective sensitivity, specificity, and accuracy for Ultrasonography, Non-Contrast Computed Tomography, and the whole diagnostic pathway for the diagnosis of acute appendicitis were 70.73%,80.83%, and 78.54; 100%,100%,100%, and 83.6%; and 100%,83.33% and 94.92%.

CONCLUSION: Using Ultrasonography as the first-line diagnostic tool and Non-Contrast Computed Tomography as a complementary second-line diagnostic tool, appendicitis can be diagnosed with high accuracy and the negative laparotomy rate can be brought down significantly without any increase in the risk of complications. Computed Tomography is superior to Ultrasonography for the diagnosis of acute appendicitis.

KEYWORDS: Ultrasound, Computed Tomography, Acute appendicitis