Case 15 Answer

Answer: Encapsulated Fat Necrosis

Fat necrosis has many forms in the abomen - epiploic appendigitis, omental infarct, etc. This is good example of encpasulated fat necrosis where we see a nice enhancing thick rim with a central smudgy liquified appearance. 

reference: nice review article from Radiographics: https://pubs.rsna.org/doi/full/10.1148/rg.317115046