This seroma is stable compared with the study of 3 months before. The thick walled appearance is typical but not pathognomonic for a seroma. The almost nodular appearance of the wall is also seen in fat necrosis.

Anecdotally it seems that once the seroma is thick-walled as in this case, it does not resolve any further. Aspiration is easy under ultrasound guidance and often gives symptomatic relief.