Don't get disappointed with your results. Ok, you 've found a juggular larger than the other, or, better, one narrower than the other. Your doctor could say that this is normal. Of course it is... for him. He is responsible and educated to prevent deaths. I can assume that you are still alivve, so you are a proof that this hasn't killed you.
When I talked to my vascular surgeon, I was told that I should only check the azygos, because a clot there could kill me. The juggulars were not so important to him. But, remember. MS is NOT associated with stenoses but altered venous hemodynamics which COULD be caused by focal stenoses, but they could also be caused by a narrower vein or any other reasons, unknown so far.
Only ultrasound can measure velocities inside veins. You must accumulate evidence and form a big picture. Then show it to a doctor who can translate it. Remember that doctors consider normal what does not kill you or cause problems and CCSVI has not been proven to cause any problem for them. They were not educated on that.
The thoughts above are reasonable. But I also think that my cerebral venous system will be found normal. Am I the only one that thinks that will be the only one to have an unknown form of MS unrelated to CCSVI?