A PROSPECTIVE STUDY ON THE DIAGNOSIS OF ACUTE APPENDICITIS WITH ULTRASONOGRAPHY IN THE INITIAL EXAMINATION

Abstract

The diagnostic accuracy of ultrasonography for appendictis in the initial examination was prospectively studied in 636 consecutive patients with suspected acute appendicitis from February 1992 to January 1994. Ninety seven patients were diagnosed as acute appendicitis by ultrasonography, but in eight patients of them pathological examination revealed catarrhalis or normal appendix considered out of operation. On the other hand, 22 out of 539 patiens who were not diagnosed as appendicitis by ultrasonography on the initial examination were operated on later based on other findings, and 13 of 22 patients had phlegmonous or gangrenous appendix which should demand appendectomy. From these results, the sensitivity, specificity and overall accuracy of ultrasonography for acute appendicitis were 87.3, 98.5 and 96.7%, respectively. Although the rate of negative appendectomy was relatively high as 14% in all operated cases, nine (53%) of 17 negative appendectomy cases underwent laparotomy with only abdominal findings. We think that when a patient having peritoneal irritation signs is not diagnosed as acute appendicitis by ultrasonography, the patient should be in hospital under close observation and followed by ultrasonography.