Certificate In Diagnostic Ultrasound
Falciform fat is a large fat pad that is located at the base of the abdominal wall, in the falciform ligament of the liver.
Falciform fat may be seen in the near field along the ventral margin of the liver, especially in overweight animals, and should not be mistaken for hepatic parenchyma.
The abdominal organs are surrounded by mesentery and omentum. On radiographs, the fat stored in these structures are what allow us to see the serosal surfaces of the soft tissue density organs. Fat is hyperechoic on ultrasound, giving a fairly uniform background for the abdominal
organs. You can see examples in the falciform fat ventral to the liver, and retroperitoneal fat surrounding the kidneys. Sometimes the fat is even more hyperechoic than usual, and that can be an important clue in diagnosing disease.
Liver margination and comparative echogenicity to the falciform fat.
(A) Image of the falciform fat. Note the linear subcutaneous facial planes and falciform fat. Liver echogenicity can be similar to the falciform fat. This especially depends on sonographic gain settings and hence comparative echogenicity can vary. This image demonstrates the delineation between the falciform fat and normal liver by the thin echogenic line (arrow) representing the liver capsule.
(B) Another example of the contrast in echogenicity between the liver and falciform fat. Note the sharp, normal liver margin.