Well I digested slowly and methodically, all the while understanding there wouldn't be any true zingers in there, but grateful that there is something substantial to bring to the table now, especially for those seeking to explore this with their medical professionals. Some parts I read and reread and sometimes 5 times so as to really understand them. While some will try to poke holes through it "because it's not blinded", the paper clearly states as such at the end and invites continuing testing of the theory independently and blinded. Not sure how much more clearer they could have been !
I understand that's been elucidated in here frequently and for awhile now, but bears repeating nonetheless. There's no "gotcha" moments but just blithely saying as some have on the net, "Aha, it's not blinded, this study is junk!", is avoiding the real gems of data that are contained therein. At the end of p.1355 into 1366, it states:
Venous pressure measurement is a key point in our
study. With patients supine, values of pressure recorded in
segments showing a stenosis were more elevated but not
significantly different from those registered in segments
with a normal venogram. This result is not surprising. All
patients presented stenoses, although differently located, in
a freely communicating venous tree. Presumably, this affects the measurements in venous segments with no evidence
In contrast, pressure in the AZY and in the IJVs was
previously measured as being significantly higher in patients
vs controls, testifying to the hemodynamic significance of
venous obstruction.4 In the present study, PTA significantly
decreased venous pressure in all the treated segments
(Fig 6), immediately correcting one of the more obvious
So strictly measuring pressure gradients, either across stenosis or the venous system, pre-op, will NOT show any conclusive evidence of stenosis. I think this is a point that is important to understand. Vs. controls, yes, but you sitting there getting measured independtly won't show much at all. Aha but then you get a procedure, and it has a profound effect on the localized pressures, although I didn't see sytemwide type pressures post-op specifically mentioned, but we get the point.
That alone I believe is a significant finding, that should be easy to replicate and confirm independently.
The lack of azy restenosis is intriguing. The rate of jugular restenosis is lamentable, but since a retreat is easily obtained, and hopefully they'll get more to the bottom of that. It will be interesting to see how the re-treats far in the future, as they adjusted the inflation pressure from 16 atm to 20 atm to see if that will correct the problem, possibly reducing future re-stenosis rates down into a more acceptable range..
We are currently evaluating the secondary patency in
the same cohort in which we performed a second treatment
at the end of the follow-up using a high-pressure (20 atm)
balloon. Another possible option could be open surgery,
especially in patients who experienced clinical and MRI
benefits after PTA, followed by worsening or relapse, or
both, with concomitant restenosis
It's great to have the paper. They put enough caveats at the end to satisfy the critics for the time being, IMHO. True critics, not those with a dinosaur sized bone to pick...
ps I'm also curious about the method of contrast dye delivery, and the localized manometer measurements, as they seem to get very specific to the are involved both before and after, especially the azygous. Is this an internal measurement that is being used at Stanford? I haven't the foggiest if there is a before/after pressure measurement. Back to the dye, it says "retrograde contrast medium was injected manually", does that mean they IV'd the dye or put it locally? I know our dye was IV'd. I'm also curious about the number of membranous obstructions that were specific to the azy. Seems obvious to me at least that the physical disruptions happening in the azy are vastly different than the noted annulus of the IJV's. I know that's calling the sun yellow but still interesting.
RRMS Dx'd 2007, first episode 2004. Bilateral stent placement, 3 on left, 1 stent on right, at Stanford August 2009. Watch my operation video: http://www.youtube.com/watch?v=cwc6QlLVtko
, Virtually symptom free since, no relap