Sonographic diagnosis of right segmental omental infarction

Purpose. The purpose of this study was to identify the characteristic features of omental infarction so that this entity can be differentiated from other acute conditions in the right lower quadrant of the abdomen. Methods. A retrospective review was undertaken. We searched our hospital medical records and found 6 patients with the diagnosis of omental infarction in the last 3 years. Clinical, sonographic, and CT findings at the time of hospital admission and at follow-up were studied. Results. In 5 of the 6 patients (83%) sonography demonstrated a moderately hyperechoic, noncompressible ovoid mass located in the omental fat between the umbilicus and the right colon corresponding to the point of maximal tenderness or to the site of a palpable lesion on physical examination. In 1 patient, sonography revealed no abnormalities. In all patients, the diagnosis of omental infarction was confirmed by CT. One patient underwent laparoscopy because of intractable pain; laparoscopy revealed a necrotic segment in the omentum, and pathologic analysis confirmed the original diagnosis. Conclusions. Omental infarction is a benign self-limited disease that can mimic acute abdomen. The diagnosis can be established preoperatively with sonography and CT, which may avoid unnecessary laparotomy.