Aneurysms? Is there an aneurysm where the swelling appears to be along the arch? There is also an odd attachment at the top of the ascending portion. Ok, I googled for vein aneurysms and didn't find any comparison images in an azygous but did find these images of an internal jugular vein aneurysm. http://img.medscape.com/article/586/585/586585-fig3.jpgAZYGOUS VEIN
An aneurysm will have high-velocity blood flow within the central part of the aneurysm and much slower near the aneurysmal wall, with a "pseudothrombosis" effect? (http://www.medscape.com/viewarticle/586585) How does that affect drainage?
Wait, here is an aneurysm of the azygous reported in the literature, in an Ehler Danos patient: http://www.ncbi.nlm.nih.gov/pubmed/16252082
That patient was treated with a stent-graft shunt from the right hepatic vein to the azygos vein.
I don't think ballooning would do anything good for an aneurysm. Could ballooning worsen an aneurysm? Was the previous IR correct to want to stent?
Ok, now I found several more reports of azygos vein aneurysms in the medical literature: http://www.ncbi.nlm.nih.gov/pubmed?term ... 20aneurysm
Eeep! http://www.ncbi.nlm.nih.gov/pubmed/18656023 They treated the azygos aneurysm by occluding the azygos.