The cisterna chyli (CC) (plural cisternae chyli), also known as the receptaculum chyli, is a normal anatomical structure in the lymphatic system. It is seen as a saccular area of dilatation in the lymphatic channels that are located in the retrocrural space, usually to the immediate right of the origin of the abdominal aorta.
The cisterna chyli is located at the level of L1 and L2 vertebral bodies immediately right to the aorta behind the right crus of the diaphragm.
It is an elongated, sac-like structure formed by the junction of a variable number of lumbar, intestinal, liver and descending intercostal lymphatic trunks. It extends 5-7 cm in the caudocephalad axis, but the size varies greatly with patient position.
Receives lymph from the abdominal viscera as well as the abdominal wall (below the level of the umbilicus), non-alimentary viscera and lower extremities.
- anterior: right crus of the diaphragm
- posterior: L1 and L2 vertebral bodies
- left lateral: abdominal aorta
- right lateral: azygos vein
The cisterna chyli can be identified as a rounded-to-elliptical retrocrural structure with an average attenuation of 4 HU. There is no enhancement following intravenous contrast administration.
The signal intensity characteristics of the cisterna chyli on MRI are the same as those for static or slow-moving fluids with high signal intensity on fluid-sensitive MR sequences .
On CT consider:
- enlarged retrocrural lymph node
- small neurenteric cyst