CT is useful for the elderly patient in whom the diagnosis of periappendiceal abscess has not been suspected clinically due to an atypical clinical presentation. CT findings and its clinical applicability of periappendiceal abscesses were reviewed retros-pectively in 11 patients older than 40 years. The correct diagnosis was possible clinically in 4 patients(36%) The CT findings were mainly cystic (45%) of mixed (36%) masses which were located inferomedially to cecum(55%) or medially to right-sided colon (27%) The common associ-ated findings were adjacent peritoneal and intestinal thickenings mesenteric and/or omental ated findings were adjacent peritoneal and intestinal thickenings. mesenteric and/or omental infiltrations in most of the cases and retroperitoneal extensin of the inflammatory process(55%) . However there we five false-positive diagnoses in patients with a fluid-filled cecum a noncomplicated acue appendicitis and three chronic inflammatory diseases of the pericecal area. CT has the potential advantage of directly imaging the periappendiceal inflammation with a full assessment of the nature localization and extension of the abscesses and may guide percutaneous drainage of abscesses as an alternative to surgical drainage.