Epiploic appendages are small adipose protrusions from the serosal surface of the colon.
Epiploic appendagitis is thought to occur as a result of spontaneous torsion, ischemia, or inflammation of an epiploic appendage of the colon. The condition presents with acute focal abdominal pain that simulates appendicitis when located in the right lower quadrant or diverticulitis when located in the left lower quadrant.
On helical CT, the lesion shows a characteristic appearance as an ovoid fat-attenuation focus with a hyperattenuating rim associated with the serosal surface of the adjacent colon. Mild inflammatory changes of the surrounding fat may be seen.
Epiploic appendagitis has been reported in approximately 1% of patients clinically suspected of having appendicitis.
It is very important to make a positive diagnosis of this characteristic entity since epiploic appendagitis is a self-limiting disease.
Both US and CT will depict an inflamed fatty mass adjacent to the colon.