Diagnostic Ultrasound - Abdomen and Pelvis

Epiploic Appendagitis
Diagnoses: Bowel
TERMINOLOGY
• Ischemic infarction of epiploic appendage (may be primary
or secondary)
IMAGING
• Noncompressible avascular hyperechoic oval mass,
adjacent to colon, deep to region of maximal tenderness
• Normal or mild localized asymmetric thickening of adjacent
colonic wall
• Peripheral 2-3 mm hypoechoic/hyperattenuating rim of
inflamed visceral peritoneum: Hyperattenuating ring sign
• Central focus of hypoechogenicity/hyperattenuation
(central engorged or thrombosed vessel &/or central areas
of hemorrhage): Central dot sign
TOP DIFFERENTIAL DIAGNOSES
• Segmental omental infarction
• Diverticulitis
• Appendicitis
KEY FACTS
• Sclerosing mesenteritis
• Primary tumors and mesocolon metastases
• Pelvic inflammatory disease
PATHOLOGY
• Torsion of epiploic appendage along its long axis with
impairment of its vascular supply and subsequent venous
thrombosis or spontaneous central vein thrombosis
resulting in necrosis
DIAGNOSTIC CHECKLIST
• Differentiate from more common causes of acute
abdominal pain (especially acute appendicitis and
diverticulitis)
• Pericolonic avascular ovoid fatty lesion with visceral
peritoneal thickening at site of maximal tenderness
• Most common in sigmoid but not limited to left colon
(Left) Graphic shows a torsed
and infarcted epiploic
appendage and 2 adjacent
normal appendages. (Right)
Axial NECT shows normal
sigmoid colon epiploic
appendages of fat density
outlined by ascites.
(Left) Grayscale
transabdominal ultrasound at
the point of maximal
tenderness in a patient with
clinically suspected ovarian
torsion shows an ovoid
hyperechoic mass adherent
to the colonic wall ſt. (Right)
Axial CECT of the same
patient demonstrates an ovoid
fat-density lesion with a
hyperattenuating rim and
surrounding inflammation
abutting the sigmoid colon
consistent with epiploic
appendagitis.
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