Clinical Presentation

A 50-year-old woman presents to the emergency department with the recent onset of left lower quadrant pain.

Enhanced axial computed tomography (CT) shows a fatty structure anterior to the sigmoid colon surrounded by a hyperdense rim (arrow) and edematous fat stranding. A central focus of increased density within this structure represents infarcted vein due to torsion of the vascular pedicle of the epiploic appendage, which is the root cause of this condition.

Differential Diagnosis

• Acute epiploic appendagitis: This usually presents as an oval fatty structure adjacent to the anterior sigmoid colon surrounded by a hyperdense ring.

• Omental infarction: This can also present as a larger structure in the right lower quadrant with a heterogeneous whirl of stranded fat between the abdominal wall and ascending/transverse colon. However, it displays no hyperdense ring in most cases.