Ischemic infarction of epiploic appendages (small pouches filled with fat, located along colon)

Noncompressible, hyperechoic oval mass, adjacent to colon, deep to region of maximal tenderness

Adjacent absent or minimal bowel wall thickening with local mass effect

Hypoechoic rim of inflamed visceral peritoneum (93%)

± central hypoechoic areas of hemorrhagic change

Color Doppler: Absence of central blood flow

Contrast-enhanced ultrasound

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  Rim of peripheral arterial hyperenhancement

  
  
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  Central, nonenhancing hypoechoic regions

Segmental omental infarction

Diverticulitis

Appendicitis

Sclerosing mesenteritis

Primary tumors and mesocolon metastases

Pelvic inflammatory disease

Torsion of epiploic appendage along its long axis with impairment of its vascular supply and subsequent necrosis

Rectosigmoid junction is most common site

4th-5th decades of life; male predominance (M:F = 4:1)

Abrupt onset of very localized abdominal pain, most frequently left lower quadrant, gradually resolving over 3-10 days, palpable mass (10-30%)

Mild or absent systemic symptoms and signs

Obesity and strenuous exercise are recognized risk factors

Conservatively managed

Usually self-limiting condition with clinical recovery within 10 days

Use combination of linear and curved transducers over area of maximal pain and tenderness