A Prospective Clinical Study Evaluating the Diagnostic Accuracy of Ultrasonography and Contrast-Enhanced Computed Tomography in the Preoperative Assessment of Patients Presenting With Acute Appendicitis

Abstract

Background: Acute appendicitis is a common surgical emergency in which early and accurate diagnosis is essential to prevent complications and unnecessary appendicectomy. Although ultrasonography (USG) is widely used as an initial imaging modality, contrast-enhanced computed tomography (CECT) may provide greater diagnostic accuracy. The present study was undertaken to compare the diagnostic accuracy of USG and CECT in patients with suspected acute appendicitis.

Materials and Methods: A prospective observational clinical study was conducted in the Department of Surgery at the Kodagu Institute of Medical Sciences, Madikeri, Karnataka, over 6 months. A total of 75 consecutive patients with clinically suspected acute appendicitis were included. All patients underwent clinical assessment and USG, while CECT was performed where clinically indicated and feasible. Operative findings and histopathological examination were used as the reference standard. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy were calculated for both imaging modalities.

Results: Among the 75 patients, 58 (77.3%) had histopathologically confirmed acute appendicitis. USG correctly identified 48 of these patients and demonstrated a sensitivity of 82.8%, specificity of 76.5%, PPV of 92.3%, NPV of 56.5% and diagnostic accuracy of 81.3%. CECT correctly identified 55 patients with acute appendicitis and demonstrated a sensitivity of 94.8%, specificity of 94.1%, PPV of 98.2%, NPV of 84.2% and diagnostic accuracy of 94.7%. Thus, CECT demonstrated superior diagnostic performance compared with USG.

Conclusion: CECT demonstrated higher diagnostic accuracy than USG in the preoperative diagnosis of acute appendicitis. USG remains a useful initial radiation-free investigation, while CECT may be considered in patients with equivocal ultrasound findings, persistent clinical suspicion or suspected complications.