title: On the Role of Ultrasonography and CT Scan in the Diagnosis of Acute Appendicitis.
abstract: The purposes of this study were to revisit the utility of ultrasonography (USG) as a primary imaging modality in acute appendicitis (AA) and to establish the role of CT scan as a second-line/problem-solving modality. All cases of suspected AA were referred for urgent USG. USG was done with standard protocol for appendicitis. Limited computed tomographic (CT) scan [NCCT ± CECT (IV contrast only)] was done for the lower abdomen and pelvis where sonographic findings were equivocal. One hundred and twenty-one patients were referred for USG for suspected appendicitis. Eight-four patients underwent surgery for AA based on clinical as well as imaging findings, of whom 76 had appendicitis confirmed at histopathology. Three patients were misdiagnosed (3.6 %) on USG as appendicitis. Of 76 patients of appendicitis confirmed histopathologically, 63 (82.8 %) had features of appendicitis on USG and did not require any additional imaging modality. Of 121 patients, 12 (10 %) needed CT scan because of atypical features on USG. Of these 12 patients, seven had retrocecal appendicitis, and three high-up paracolic appendicitis. USG alone had sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of 81, 88, 92.6, 71.6, and 83 %, respectively. When combined with CT scan in select cases, the sensitivity, specificity, PPV, NPV, and accuracy of combined USG + CT scan were 96 % (P = 0.0014), 89 %, 93 %, 93.5 % (P = 0.0001), and 93 % (P = 0.0484), respectively. Twenty-eight (23 %) patients were given alternative diagnosis on USG. Dedicated appendiceal USG should be used as a primary imaging modality in diagnosing or excluding AA. Appendiceal CT can serve as a problem-solving modality.
authors.affiliation: Department of Radiology, Armed Forces Medical College, Pune, 411 040 Maharashtra India.
authors.forename: Jyotindu
authors.initials: J
authors.lastname: Debnath
authors.affiliation: Department of Surgery, 151 Base Hospital, Guwahati, India.
authors.forename: Rajesh
authors.initials: R
authors.lastname: Kumar
authors.affiliation: Department of Radiodiagnosis and Imaging, 167 Military Hospital, Pathankot, 145001 Punjab India.
authors.forename: Ankit
authors.initials: A
authors.lastname: Mathur
authors.affiliation: Department of Surgery, 167 Military Hospital, Pathankot, India.
authors.forename: Pawan
authors.initials: P
authors.lastname: Sharma
authors.affiliation: Pathology, 167 Military Hospital, Pathankot, India.
authors.forename: Nikhilesh
authors.initials: N
authors.lastname: Kumar
authors.affiliation: Anesthesiology, 167 Military Hospital, Pathankot, India.
authors.forename: Nagaraj
authors.initials: N
authors.lastname: Shridhar
authors.affiliation: Department of Surgery, Military Hospital, Dehradun, India.
authors.forename: Ashwani
authors.initials: A
authors.lastname: Shukla
authors.affiliation: Pathology, 167 Military Hospital, Pathankot, India.
authors.forename: Shiv Pankaj
authors.initials: SP
authors.lastname: Khanna
keywords: Appendicitis; CT scan; Ultrasonography