Ultrasonographic (Usg) Evaluation of Acute Appendicitis

Abstract

BACKGROUND:The diagnosis of acute appendicitis is mainly clinical and to augment the clinical diagnosis ultrasonography (USG) of the abdomen is being used to help in diagnosis of the disease. AIM: To find out the role of USG in the diagnosis of acute appendicitis in clinically equivocal cases and to correlate USG findings with histopathological reports (HPR) of removed appendix. MATERIALS AND METHODS:This study was performed during the period from November 2012 to March 2014.It wasnon-randomized, prospective study of 56 clinically suspected cases of acute appendicitis. All of them underwent ultrasound evaluation. A histopathological examination was performed on all surgically removed appendices, which formed the basis for definitive judgment.Patients not undergoing surgery were excluded for calculating sensitive and specificity. The diagnostic accuracy of sonography was examined using the NPV, positive predictive value (PPV), negative and positive likelihood ratios, sensitivity, specificity, and their respective 95% confidence intervals (CIs). RESULTS: Out of 56 patients, 38 patients were correctly diagnosed as having acute appendicitis on USG out of 47 finally diagnosed cases based on histopathological reports. This showed that USG scan has sensitivity of 89.74%, specificity of 77.78%, positive predictive value of 94.44% and negative predictive value of 87.23%. The most accurate appendiceal finding for appendicitis was a diameter of 6 mm or larger followed by non-compressibility of inflamed appendix. CONCLUSION: USG has high accuracy in diagnosing acute appendicitis and reduces negative appendectomies. Greater than 6-mm diameter of the appendix under compression is the most accurate USG finding with high positive predictive value for the diagnosis of acute appendicitis. Surgery followed by histopathological examination was the ultimate proof of acute appendicitis.