Right-sided segmental infarction of the omentum: clinical, US, and CT findings.

Clinical, ultrasound (US), and computed tomographic (CT) findings at hospital admission and follow-up were retrospectively studied in seven patients with right-sided segmental infarction of the omentum. In all patients, the presumptive clinical diagnosis was appendicitis, although in three patients cholecystitis and pyelitis were also considered. US revealed an ovoid or cakelike, moderately hyperechoic, noncompressible lesion adherent to the peritoneum and located at the level of the umbilicus, anterolateral to the right half of the colon. On CT scans, a corresponding, better defined area of fat interspersed with hyperattenuating streaks was found. No abnormality of bowel or appendix was seen. The clinical symptoms and abnormalities on US scans gradually disappeared in all patients. Because no patient underwent surgery, no histologic proof was obtained. In all patients, however, the clinical, US, and CT findings were similar and consistent. They corresponded to the abnormality called right-sided segmental omental infarction in the surgery and radiology literature and enabled exclusion of appendicitis, thus preventing unnecessary surgery.