Omental torsion and infarction: CT appearance.

A 42-year-old male presented to the Emergency Department complaining of right lower quadrant pain of 2 days duration. He had no previous surgical history. On physical exam, the patient was afebrile with diffuse abdominal tenderness and peritoneal irritation. White blood cell, electrolytes, amylase and lipase serum levels were normal. A contrast-enhanced CT scan of the abdomen and pelvis (Picture 1) showed diffuse streaking of the greater omentum extending downwards and anteriorly to reach the pelvis, with a focal mass of fat density showing streaks in a whirling pattern. The fatty mass was located anteriorward in the greater omentum just below the ascending colon. There was no thickening of the adjacent bowel walls or abscess formation. Exploratory laparotomy revealed diffuse infarction of the greater omentum with a focal mass of omental torsion which extended along the lateral abdominal wall terminating in the upper right abdomen. Segmental infarction of the greater omentum is a rare cause of acute abdomen (1). Its etiology is uncertain although several predisposing factors have been underlined such as congenital venous anomalies, sudden change of position and substantial meal (2). The clinical picture simulates an appendicitis, diverticulitis, or cholecystitis (1, 3). Computed tomography scan findings such as a streaking or “whirling” pattern of inflammatory tissue and a fluid cavity based on the degree of necrosis present, can help to make this diagnosis preoperatively (1, 4). This will help to avoid unnecessary surgery since conservative management has been suggested in the absence of complications (1, 3).