- Background: The most efficient approach to diagnosis of acute appendicitis (AA) continues to be a challenge. We sought to determine diagnostic accuracy, sensitivity, and specificity of computed tomography (CT), ultrasonography, and laparoscopy and compared benefits and advantages in patients with suspected AA. Patients and methods: A retrospective review of all patients who had laparoscopic surgery between January 2000 and December 2009 was conducted. Preoperative information, surgery results, and outcomes were compared. Results: Of 887 laparoscopic procedures performed for suspected AA, 254 (29%) patients had preoperative imaging: 171 CT scans and 83 ultrasound (US) scans. Overall, 754 patients underwent laparoscopic appendectomy (LA), and 133 underwent diagnostic laparoscopy (DL). DL was negative in 23 patients. The sensitivity of LA was higher than that of CT (98% versus 94%), whereas the specificity of LA was higher than that of CT and US in complicated appendicitis and in women. Complicated AA was significantly less common in patients who underwent laparoscopic surgery compared with patients evaluated by preoperative CT. Comparing the kappa value between the preoperative diagnosis by imaging and DL, a weak agreement was found (κ=0.234 ± 0.057). Conclusions: Laparoscopy achieves early and accurate diagnosis of AA and can reduce the incidence of perforated appendicitis. Abdominal CT remains a valuable diagnostic tool. DL is useful in the early stages of the diagnostic work-up and avoids unnecessary exposure to radiation of the abdomen and pelvis in young women.