Computed tomography and ultrasonography in the diagnosis of equivocal acute appendicitis. A meta-analysis.

Acute appendicitis is the most common acute surgical condition of the abdomen. Computed tomography (CT) and Ultrasonography (US) can reduce the rate of complications and unnecessary appendectomies, in addition, they can establish an alternative diagnosis. We carried out a systematic review to evaluate the evidence relating radiological imaging (US and CT scan) and early detection of acute appendicitis in patients presenting with equivocal findings, and to provide recommendations to use radiological imaging (US and CT scan) in diagnosing acute appendicitis as part of the initial clinical assessment of the patients presenting with equivocal findings to reduce complications and unnecessary appendectomies. We used the MEDLINE to search for articles published from 1966 to December 2005 that related to radiological imaging of acute appendicitis; additional articles were identified from the bibliographies of review articles. Selection criteria were used to limit the analysis to prospective studies with more than 100 patients involved in each study as a study group. Forty-five studies fulfilling our inclusion and exclusion criteria were extracted, and 13,046 patients were included. Although the CT scan was more sensitive than US in diagnosing patients with equivocal appendicitis (93.4% [95% CI 92.1-94.6] versus 83.7% [95% CI 82.3-85.0]), either diagnostic study should be used as part of the initial assessment of the patients presenting with equivocal findings.