A rounded, fluid-density (~20HU) retrocrural structure is located between the aorta and IVC. It measures 24 x 30 mm. The structure displaces both vessels however fat planes are preserved. There is no solid component or internal complexity and the lesion has a benign apperance.
Differential diagnoses for this finding included an enlarged cisterna chyli, foregut duplication cyst or less likely a cystic GIST.