valve malformations in healthy volunteers

A forum to discuss Chronic Cerebrospinal Venous Insufficiency and its relationship to Multiple Sclerosis.

valve malformations in healthy volunteers

Postby Cece » Mon Dec 06, 2010 6:45 pm

Functional and Morphological Criteria of Internal Jugular Valve Insufficiency as Assessed by Ultrasound
Max Nedelmann MD, B. Martin Eicke MD, Marianne Dieterich MDArticle first published online: 13 FEB 2006

Journal of Neuroimaging
Volume 15, Issue 1, pages 70–75, January 2005

ABSTRACT
Background and Purpose. Jugular venous valve insufficiency may play a role in different neurological diseases. This study describes the methodology to detect internal jugular valve insuf ficiency and establishes functional and morphological criteria to discriminate retrograde flow during valve closure from retro grade insufficiency flow. Methods. Valve closure was assessed in 100 valves (50 healthy volunteers). The valves were visualized in B-mode. During a pressure-controlled Valsalva maneuver, valve closure was monitored by color duplex. The duration and the peak velocity of retrograde flow were determined. Results. Backward flow during valve closure in competent valves was visually clearly discernible from a retrograde flow jet through insufficient valves. Insufficiency was found in 29% of valves. The duration of backward flow in competent valves was between 0.22 and 0.78 seconds (mean = 0.46 ± 0.14 seconds on Dopp ler measurements) and in insufficient valves between 1.23 and 6.15 seconds (mean = 2.66 ± 1.28; P < .0001). Peak velocity of retrograde flow in competent valves was between 12 and 65 cm/s (mean = 26.2 ± 11.1 cm/s) and between 25 and 160 cm/s (mean = 89.5 ± 39.3 cm/s; P < .0001) in insufficient valves. On B-mode imaging, the “typical” aspect of an immobile, frozen valve was seen only in 5 cases of insufficient valves; 21 insuffi cient valves did not display this aspect. Conclusion. The dura tion of retrograde flow clearly discriminates competent and incompetent valves. On the basis of our results, we provide cut off values that help differentiate between physiological and insufficiency reflux. The differences in peak velocity and morphology criteria are helpful but not reliable to predict insufficiency of the valve.

http://onlinelibrary.wiley.com/doi/10.1 ... x/abstract

An immobile frozen IJV valve sounds like potential CCSVI to me. Here it was found in 5% of valves in a study of 100 valves (50 healthy volunteers).

The rest of the study is looking at the other type of reflux, the kind Doepp got confused by, that is present under Valsalva and is venous valve insufficiency of the "backflow" variety, not the frozen immobile valve outflow obstruction variety.
Cece
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Re: valve malformations in healthy volunteers

Postby David1949 » Tue Dec 07, 2010 2:14 pm

Cece wrote:
Functional and Morphological Criteria of Internal Jugular Valve Insufficiency as Assessed by Ultrasound
Max Nedelmann MD, B. Martin Eicke MD, Marianne Dieterich MDArticle first published online: 13 FEB 2006

Journal of Neuroimaging
Volume 15, Issue 1, pages 70–75, January 2005

The duration of backward flow in competent valves was between 0.22 and 0.78 seconds (mean = 0.46 ± 0.14 seconds on Dopp ler measurements) and in insufficient valves between 1.23 and 6.15 seconds (mean = 2.66 ± 1.28; P < .0001).

http://onlinelibrary.wiley.com/doi/10.1 ... x/abstract



What I find most surprising about this is that in insufficient valves blood can flow backward for up to 6.15 seconds. In other words it is flowing backward over a period of several heartbeats. My earlier understanding of reflux was that blood would flow in the normal direction during each heart beat but would flow backward between heartbeats. Am I reading the article correctly?
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Re: valve malformations in healthy volunteers

Postby Cece » Tue Dec 07, 2010 2:32 pm

David1949 wrote:What I find most surprising about this is that in insufficient valves blood can flow backward for up to 6.15 seconds. In other words it is flowing backward over a period of several heartbeats. My earlier understanding of reflux was that blood would flow in the normal direction during each heart beat but would flow backward between heartbeats. Am I reading the article correctly?

I think you are reading this correctly but I believe it is under Valsalva conditions. This is the other type of reflux (when the valve lets blood out but lets it back in again). In our type of reflux, the blood doesn't get out that way in the first place, so it refluxes back from the obstruction, but blood that gets past the obstruction (perhaps via collateral) will not backflow back through it again.

I'm ignoring all the descriptions of that other sort of reflux in these papers as irrelevant to CCSVI, it's why I considered the talk of frozen immobile valves in the jugular to be the salient detail.

However you make a very interesting point about reflux vs solid reverse flow. I'd not heard of reverse flow until I interpreted (or perhaps misinterpreted) the flow graphs that came with my Haacke protocol MRV. This is from the explanation for what the Haacke MRV results mean:
http://www.ms-mri.com/docs/ms-report-in ... mh-9pm.pdf
Five graphs are shown including; total integrated flow per cardiac cycle, flow rates in
the form of total, positive and negative, and average speed coincide with the magnitude and
phase images. These allow us to determine if there are abnormal flow patterns such as no flow,
reverse or reflux flow, and circulatory flow patterns (often the case for widened bulbous lower
levels in the internal jugular veins). If the flow curves for a given vein fall through zero and
change direction, then we refer to this as reflux flow. However, on occasion the vessel shows
flow in both directions at any given time. This we refer to as circulatory flow.

So those are the possible variations of flow in CCSVI: no flow, reverse or reflux, and circulatory flow. My own MRV appeared to show reflux (positive, then dropped past the zero to negative, then back to positive) in the azygous but in the jugulars and straight sinus it fluctuated within the negative side but never made it past the zero to the positive, which would seem to be reverse flow, which I don't hemodynamically understand.

A friend suggested that negative might mean positive and positive negative, but the azygous seems interpreted correctly; you'd expect the positive surge at the start of the cardiac cycle, then the drop to negative, then positive again, not the opposite.
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