No sure about your numbers- some of the other members that had that test might be able to help with those.

but found this on the R vs L differences-
[An interesting finding in our study is difference between right and left vertebral arteries in patients younger than 60 year old. We have showed that in young adults peak systolic velocity (PSV) and flow volume (FV) in left vertebral artery are significantly higher than right side. We think that this is because of anatomical difference of right and left vertebral arteries; in right side, subclavian artery originates from brachiocephalic artery but left subclavian artery directly originates from aorta, beside this branching angle of left vertebral artery from subclavian and also branching angle of left subclavian from aorta is more acute than same angles in right side. ]
http://www.cardiovascularultrasound.com/content/7/1/2

What kinds of things were they doing- or having you do, during the PT sessions?
weights or strengthening? stretches, or basic posture work?

Also sometimes the extra c ribs are small or only partial, unless it has been a lifelong problem, something has changed to make them cause the problems.

What kind of work do you do, or any previous upper body injuries, car accident, sports etc?