Accuracy of ultrasonography in the diagnosis of acute appendicitis.

AIMS AND OBJECTIVES To assess the accuracy of ultrasonography in the diagnosis of acute appendicitis. METHODOLOGY A prospective randomized study was carried in the Dept. of Radiology and Imaging, Tribhuvan University, Teaching Hospital, Maharajgunj, Kathmandu, Nepal. A total of 120 patients, who were clinically diagnosed as acute appendicitis were subjected to ultrasonography of the abdomen. A detailed ultrasonography was performed and the findings were recorded. Twenty one cases had alternate diagnosis. Ninety nine cases ultimately underwent laparotomy and the retrieved appendices were sent for histopathological examination. Intra-operative, histopathological and ultrasonographic diagnoses were then statistically analyzed. RESULTS Ultrasonographic, intra-operative and histopathological findings were statistically insignificant (P0.05). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy percentage of ultrasonography in the diagnosis of acute appendicitis was 85.7%, 100%, 100%, 6.7% and 85.9% respectively. CONCLUSION Ultrasonography has a high degree of accuracy in the diagnosis of acute appendicitis. However, the diagnosis should be considered with the diameter of appendix over 6 mm. Therefore acute appendicitis with diameter of appendix having less than 6 mm should be evaluated with other diagnostic parameters.