Effect of ultrasonography and optional computed tomography on the outcome of appendectomy

The aim of this study was to investigate the value of US and complementary CT in patients with suspected appendicitis, and to detect adverse outcomes of preoperative imaging. We retrospectively reviewed the data of 233 consecutive patients who underwent an appendectomy as an emergency procedure in our hospital, within a 2-year period. Our hospital policy is to perform diagnostic imaging in all patients with clinical suspicion of appendicitis. The US was performed in 227 patients, followed by additional unenhanced helical focused appendiceal CT in 30 patients with equivocal US results. We evaluated the negative appendectomy rate, occurrence of perforation, and our in-hospital delay. Acute appendicitis was pathologically proven in 219 patients, corresponding to a negative appendectomy rate of 6%. The US with optional CT diagnosed appendicitis with a sensitivity of 96.7%. Forty-eight appendices (21.9%) were perforated. The median overall in-hospital delay was 5 h (range 0.5-123.5 h). For the perforated appendices this was 4.5 h (range 0.5-64.5 h), for the non-perforated appendices 6.0 h (range 0.5-123.5 h). In patients with suspected acute appendicitis, US examination with the option of additional CT significantly lowers the negative appendectomy rate as compared with the clinical acumen alone, without adverse effects on the perforation rate or the in-hospital delay.