ABSTRACT
PURPOSE: This study was performed to evaluate the usefulness of abdominal computed tomography (CT) for patients with right lower quadrant (RLQ) pain. METHODS: Between January 2006 and July 2008, 191 consecutive patients with RLQ pain underwent abdominal CT (CT group). Forty-two patients who had undergone abdominal ultrasound (US group) and 52 patients without abdominal CT or abdominal ultrasound for RLQ pain (clinical Dx group) underwent emergent operations. Using the Alvarado scoring system, we scored all patients. The abdominal CT was performed in the abdominal and pelvic area with contrast. RESULTS: One hundred twenty-one (63.4%) of the 191 patients in the CT group were preoperatively diagnosed as having acute appendicitis and underwent surgery. There were three cases of negative appendectomy (1.6%). In the US group and the clinical Dx group, the negative appendectomy rates were 4.8% and 3.8%, respectively. The sensitivity of the abdominal CT was 96.7%. In the CT group, in addition to acute appendicitis, colitis, nonspecific enteritis, diverticulitis, urinary stone, ovary, uterine, and diseases were indentified. CONCLUSIONS: In this study, abdominal CT scans in patients with RLQ pain were useful for the diagnosis acute appendicitis and for the differential diagnosis of other diseases presenting with RLQ pain. The false positive rate was significantly lower in the CT group than in the other groups.