The CT shows an ovoid fat density structure arising from inferior to the falciform ligament and lying anterior to the left lobe of the liver. There is streaky increased attenuation noted around the base of the lesion, with a twisting morphology discernable on the sagittal reformatted images (below). An enhancing margin is noted around the lesion. There is no associated focal liver or gallbladder lesion and no free intraperitoneal gas or fluid. The abnormality is distinct from the adjacent transverse colon.
The findings are in keeping with infarction of a fatty appendage of the falciform ligament, an entity falling within the umbrella term of "intraperitoneal focal fat infarction" or IFFI. Other and more common types of IFFI include epiploic appendagitis. The diagnosis is important to make accurately as management is usually conservative. CT is the key diagnostic tool as it excludes other more serious pathology such as visceral perforation.