This Is MS Multiple Sclerosis Community: Knowledge & Support

i don't know if article has been posted but should be read.





http://www.nature.com/jcbfm/journal/v28 ... 0872a.html



Bob

Ok, we know one thing the reduced perfusion is not due to (it is not secondary to axonal loss). The article suggests a complicated theory relating to astrocytes as a possibility.

The idea around here has been that the reduced perfusion is due to the blockages in the neck veins. But there is an easy way to test this idea. Perfusion needs to be measured before and after the endovascular treatment of the stenoses of the neck veins. If improving the outflow through the neck veins also improves the cerebral perfusion, then the reduced perfusion was a result of those blockages.

I do not know if there is as easy of a way to test the astrocyte theory.

Great article, orion. I will read it more closely tomorrow. My astrocytes get a little tired at this time of night.

this is a good one, orion.
I wrote a note in Facebook on this paper back in 2009, delving into a bit, and breaking it into bite size chunks.
https://www.facebook.com/notes/ccsvi-in ... 9656952210



cheer

_________________
Husband dx RRMS 3/07
dx dual jugular vein stenosis (CCSVI) 4/09
dual stents placed 5/09
CCSVI in MS

I think there is reduced perfusion if the cerebral bloodflow (sum of all flows going in, which equals the sum of all outflows) is low. It's just a question of which part gets the reduced flow, if it isn't evenly perfused. I believe the p in PWI is perfusion, so yes, it can be measured, with MRI. Measuring the astrocytes, no clue.

Further to the thread on metabolism, I think, though flow is the same on both sides of a stenosis (in the jugular), there must be a difference in pressure. I think the pressure should be higher on the upstream side (brain-wards). Also, if the jugulars are a main route (because of the relative diameters of other veins, and the fourth power relationship between diameter and resistance), then any stenosis or obstruction will reduce the overall flow, and thus perfusion. The jugulars appear in parallel with the other veins and collaterals of the neck. The favoured route is the largest vein. That is why after stenosis is removed, the collaterals appear to vanish. The difference in diameters has such a pronounced effect that they now carry only a miniscule amount of the overall low..

So a) which jugular is affected matters, because they are not the same diameter; and b) together they comprise the favoured route, having direct series connection with large brain vessels. Overall, throughout the brain, flow, pressure, and resistance of blood are affected by a jugular stenosis.

Pressure and resistance to flow are increased, and flow (again, thus perfusion) is reduced, over the whole brain.

You can measure it, but it is a fact.

The notion that you will stay alive after ligation of the two largest vessels draining the brain may be technically true, but QOL is definitely in jeopardy.

The way they work in upright humans is mainly when we are lying down. They are a main reason we don't like to sleep standing up.

_________________
"Try - Just A Little Bit Harder" - Janis Joplin
CCSVI procedure Albany Aug 2010
'_MS' is over - if you want it
Patients sans/without patience

If we assume that low perfusion is the cause of MS then the $64,000 question is what causes the low perfusion rate and more importantly

HOW CAN WE FIX IT?

This article discusses factors that control the cerebral blood flow.
https://en.wikipedia.org/wiki/Cerebral_blood_flow

Here is an article on autoregulation of blood flow.
http://www.cvphysiology.com/Blood%20Flow/BF004.htm
Certain organs including the brain, have a means of compensating for a fall in blood pressure by dilating the small arteries and arterioles to allow more blood flow.

So as I see it there are five categories of things that could cause low blood
low:

Low blood pressure.
Blockage or stenosis in the veins
Blockage or stenosis in the arteries
Malfunction of the autoregulation system in the brain.
High viscosity of the blood.

We could probably rule out low blood pressure. I don't have low blood pressure and I think many other MSers also have normal pressure.

I asked Dr.Arata about MS patients having high blood pressure and he stated that most of his MS patients have low blood pressure. My bp is low and has been low normal for years.

Sounds like we need a poll.