Comparative evaluation of emergency non-contrast CT abdomen screening and ultrasonography in the diagnosis of acute appendicitis: A prospective observational study done at Saveetha Medical College, Chennai

Abstract

Objective: The aim of this prospective observational study was to compare the diagnostic accuracy and efficacy of emergency non-contrast CT abdomen screening and ultrasonography in the evaluation of acute appendicitis among patients visiting the Emergency Room (ER) of Saveetha Medical College, Chennai, over a two-year period from January 2020 to January 2022.Methods: A total of 500 patients presenting to the ER with suspected acute appendicitis were included in the study. All patients underwent both emergency non-contrast CT abdomen screening and ultrasonography. The findings were recorded, and the diagnostic accuracy of each modality was assessed using surgical or histopathological findings as the gold standard.Results: The 500 patients included, 285 were male and 215 were female, with a mean age of 32.4 years. The sensitivity and specificity of emergency non-contrast CT abdomen screening in diagnosing acute appendicitis were 92.3% and 95.8%, respectively, while for ultrasonography, the sensitivity and specificity were 78.9% and 90.4%, respectively. The positive predictive value (PPV) and negative predictive value (NPV) for emergency non-contrast CT abdomen screening were 89.4% and 96.2%, respectively, compared to 79.8% and 89.7% for ultrasonography. The diagnostic accuracy of emergency non-contrast CT abdomen screening was significantly higher than that of ultrasonography (p