Primary omental torsion diagnosed during hysterectomy.

Omental torsion is a rare cause of acute abdominal pain. It presents with nonspecific symptoms and signs of an acute abdomen, making it difficult to diagnose preoperatively, because symptoms mimic those caused by other conditions such as appendicitis, cholecystitis, diverticulitis, and other gynecologic diseases. Computed tomography is an effective and useful method to diagnose and exclude other acute abdominal conditions. Our case presented with sudden right upper abdominal pain with tenderness, rebound tenderness, mild fever (37.2℃), increased erythrocyte sedimentation rate (37 mm/hr), increased high-sensitivity C-reactive protein level (5.97 mg/dL). Computed tomography showed a large, well-circumscribed heterogeneous fatty mass and a 7.3 cm subserosal myoma. We could not exclude the myoma as the cause of acute abdominal pain, so we performed an emergency operation with suspicion of omental torsion or necrotic degeneration of the myoma. During the operation, we diagnosed primary omental torsion with infarction and subserosal myoma without secondary degeneration.