Does Computed Tomography Have Any Additional Value After Sonography in Patients With Suspected Acute Appendicitis?

Abstract

cute appendicitis is the most common condition requiring prompt abdominal surgery to minimize morbidity and mortality. Sonography and computed tomography (CT) have been widely used as the preferred imaging tools in patients with suspected acute appendicitis. 1 In previous studies of these diagnostic techniques, the sensitivities and specificities of sonography were 67% to 88% and 78% to 100%, respectively, whereas the sensitivities and specificities of CT were 76% to 96% and 75% to 95%. [2][3][4][5][6] Hye Soo Koo, MD, Hyun Cheol Kim, MD, Dal Mo Yang, MD, Sang Won Kim, MD, Seong Jin Park, MD, Jung Kyu Ryu, MD Received December 17, 2012, Objectives-The purpose of this study was to evaluate the additional value of supplementary computed tomography (CT) after sonography for diagnosing acute appendicitis.Methods-Among 140 consecutive patients with suspected acute appendicitis who underwent both initial sonography and supplementary CT within 12 hours, 88 patients whose appendices could not be visualized on sonography were excluded. The remaining 52 patients (mean age, 37.3 years; range, 15-98 years) were enrolled in this study. Two radiologists retrospectively reviewed the findings of 52 sonographic and CT examinations, and the appendix of each patient was classified as normal, equivocal appendicitis, nonperforated acute appendicitis, or perforated appendicitis. Causes of right lower quadrant pain other than appendicitis were also recorded. The additional value of supplementary CT was evaluated by performing head-to-head comparisons between CT and sonographic results.Results-No patients with a normal appendix on sonography showed appendicitis on CT. In addition, there were no patients with a sonographic diagnosis of appendicitis who had a normal appendix on CT. Ten patients (19.2%) were determined to have additional value gained from CT. Among these 10 patients, however, the additional information from CT affected treatment modality decisions in only 5.Conclusions-Initial sonography can be as effective as CT in patients with suspected acute appendicitis when the results are definite. Supplementary CT should only be performed when sonography is inconclusive.

The management of intra-abdominal infections from a global perspective: 2017 WSES guidelines for management of intra-abdominal infections

“…Proposals of staged algorithmics with a step-up approach with CT performed after an inconclusive or negative US were proposed in the setting of acute appendicitis and acute diverticulitis [48–51]. …”

Management of intra-abdominal infections: recommendations by the WSES 2016 consensus conference

“…Proposals of staged algorithms using a step-up approach with CT performed after an inconclusive or negative US have been proposed in the setting of acute appendicitis and acute diverticulitis [29–32]. …”

Searching for certainty: findings predictive of appendicitis in equivocal ultrasound exams

“…Equivocal exams can also result in unnecessary surgeries and negative appendectomies [3]. To avoid these harmful outcomes, some authors have suggested a protocol in which CT is performed after inconclusive US exams, thereby exposing children to the potential long-term consequences of ionizing radiation [7][8][9]. At some institutions MRI is being used instead of CT as a secondary exam to evaluate cases of equivocal appendicitis and has been found to have high diagnostic accuracy [10,11].…”