[Detection of acute appendicitis using ultrasonography]

1318 patients with a clinically equivocal diagnosis of appendicitis were evaluated using graded compression sonography. Sonographic (US) examination could able be performed in 1199 patients. Appendicitis was diagnosed if the appendiceal maximal mural thickness was 3 mm or more, or the appendices presented with luminal dilatation due to a large appendicolith or non-expressible fluid. In patients with verified appendicitis (n = 176) sonographic findings on a visualized appendix were correlated with surgical and histopathological findings. In patients who did not have surgery the reference standard was the clinical consensus based follow-up. A pathological appendix was detected in 165 cases of 176 surgically verified ones. The sensitivity of US in detecting appendicitis was 93.7%, the specificity 95.5% and the accuracy 95.2%.