Here are a few shots of my azygous vein. I noted a strange "bifurcation" in these shots. I have not seen enough images of an azygous to know for sure, but it looks to me to have collateralized.
Doc. Sclafani?
un-annotized shot of azygous.
This shot is from the TOF (time of flight) series.

My name is not really Johnson. MSed up since 1993