Periappendiceal inflammatory masses: CT-directed management and clinical outcome in 70 patients.

The outcome was reviewed in 70 patients with computed tomographic (CT) and clinical evidence of periappendiceal inflammatory masses. On the basis of the initial CT scan, patients were divided into three broad categories: (a) patients with periappendiceal phlegmons or abscesses less than 3 cm (n = 32); (b) patients with well-defined and well-localized periappendiceal abscesses greater than 3 cm (n = 28); and (c) patients with extensive, poorly defined periappendiceal abscesses with either pelvic, retroperitoneal, or interloop involvement (n = 10). Thirty-two patients with either phlegmons or small abscesses were treated initially with antibiotic therapy alone; clinical resolution of the inflammatory process occurred in 28 patients (88%). Twenty-eight patients with well-defined and well-localized periappendiceal abscesses underwent percutaneous catheter drainage, which was successful in 26 patients (93%). Nine of ten patients underwent early surgical drainage for extensive, poorly defined abscesses. One patient underwent percutaneous drainage as a temporizing measure before surgery. There were three false-positive CT diagnoses of periappendiceal abscesses in this series.