BACKGROUND Acute appendicitis (AA) is one of the commonest causes of acute abdominal emergencies. Accurate diagnosis and earlier surgery is imperative in such cases. Ultrasonography (US), and computed tomography (CT), are main stays accurate diagnosis of this disease. This study was conducted to compare the accuracy of US and CT in the diagnosis of AA and reduce number of negative appendectomies. METHODS This prospective study was done after approval from institutional ethical committee and obtaining written consent. 164 patients with clinical features suggestive of AA, were selected from emergency department of Patna Medical College, Patna India during the period from January 2019 to December 2020. 98 were males and 66 females, mean age being 18.08 years. 142 patents (86.58 %) underwent surgery, and 22 patients (13.41 %) were kept on clinical observation in hospital after imaging. After detailed clinical workup and laboratory investigations, all patients were subjected to both US and CT examination. Each patient was reevaluated clinically, and a clinical correlation was done between both sets of results. Based on these, final decision was made. Accuracy was decided based on intra-operative findings in appendectomy group and were correlated with imaging findings later with histopathologic findings. RESULTS Males outnumbered females, 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 92.6 %, 76.4 %, 95.3%, 71.0% and 88.9 % respectively. The sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy of CT in diagnosis of AA were 99.1 %, 90.5 %, 98.6%, 87.8% and 97.8 % respectively. CONCLUSIONS US should be the first-line imaging modality as it is free from radiation. CT is recommended as additional imaging tool to raise accuracy in diagnosis except in pregnancy and selected pediatric patients. KEYWORDS Acute Appendicitis, Computed Tomography, Ultrasound

Breast Ultrasonography (US) is now a days considered the first line examination in the Screening of breast for detection of early breast lesions including cancer. Yet only few single center cohort studies analyzing breast US as screening tool could be found in literature. In spite of the fact that mammography is considered as the primary method for screening for its ability to detect microcalcifications, US is good in mass or mass like lesion detection, especially in the dense breast population as proved by the study of ACRIN 6666 (American College Of Radiology Imaging Network). A lobular hypoechoic area, lesion with ductal extension and dilatation, and a hypoechoic nodular lesion with a dilated lactiferous duct leading to the retroareolar region, were the common ultrasound findings in Ductal carcinoma in situ (DCIS) have been found. Recent introduction of Computer programmes have been developed and approved for use in clinical practice, like CAD (computer aided/assisted detection/ diagnosis), ABUS (Automated breast US), elastography and microbubbles in contrast-enhanced ultrasound. The standardized scanning, with addition of computer technology implementation and finding the picture of DCIS may prove an important radiation free modality for detecting early breast cancer. Results: Out of 176 cases in which we analysed US data and compared with histocytological findings sensitivity and specificity were 94.5% and 92.3% respectively. It was concluded that conventional USG examination can very well complement the diagnosis of breast lesions including cancer. Moreover, this method has the lowest cost/efficiency ratio and it is also the most non-invasive and easily accessible imaging method, with an accuracy comparable to MRI.