ULTRASONOGRAPHY VERSUS COMPUTED TOMOGRAPHY IN DIAGNOSIS OF ACUTE APPENDICITIS

Abstract

Background: Acute appendicitis (AA) is among the most common cause of acute abdominal pain. Imaging methods, such as ultrasonography (US) and computed tomography (CT), aimed at avoiding a misdiagnosis and facilitating earlier surgery, when necessary, have become increasingly important for decreasing the morbidity of the disease. Objective: This study aimed to compare the accuracy of US and CT in the diagnosis of AA. Patients and Methods: After local ethical approval and written consent taken, 107 patients with signs and symptoms suggesting AA, selected from emergency department of Al-Azhar University Hospital, New Damietta during the period from March, 2016 to April 2017. They were 63 males and 44 females, mean age was 17.09±3.02 years. 90 (84.11%) underwent surgery, and 17 patients (15.9%) were hospitalized for clinical observation after imaging (12 patients (11.2%) were dismissed from the hospital while 5 cases (4.7%) presented with positive CT findings underwent surgery). After history taking, full clinical examination and laboratory investigations, all patients were subjected to US and CT examination. All patients were reevaluated clinically, and a correlation was made between both sets of results. Accordingly, final decision was made. Accuracy was ascertained intra-operatively for those underwent appendectomy, and the results were compared with those found by radiological examination. The results were correlated with surgical and histopathologic findings. Results: Males affected more than females, and abdominal pain was present in 100%. The sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy of US in diagnosis of AA in our study were found to be 91.7 %, 77.8 %, 94.3%, 70.0% and 88.9 % respectively.The sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy of CT in diagnosis of AA were 98.8 %, 88.9 %, 98.8%, 88.9% and 97.8 % respectively. Conclusion: US should be the first-line imaging modality. As US sensitivity is limited, and non-confirmed US examinations, diagnostic strategies and algorithms should focus on clinical reassessment and CT examination.