I have had a veinogram and a doppler ultrasound of the brachial plexus vessels.. I had no blood flow on the doppler the guy had to go out of the room for help he had never seen it before!!!!
The veinogram clinched the surgery for me....it showed over a 90% occlucion on the right side subclavian vein so it was why I had my surgery to correct this issue....I think it is still there as all my symptoms are back.........
anyhow good valid test to see about your blood flow, but make sure they put you in provocative positions...ie the superman test...arms overhead like you are flying.....and arm in weird positions....the ones that cause you problems...
best of luck love and hugs,
Victoria