CSF flow is abnormal in MS

[frodo]

I don't know if this is related to the study of Fonar and Dr. Rosa, but sounds similar. No amplitude difference found, but irregular timing was found instead.

Cerebrospinal Fluid Flow Dynamics in Multiple Sclerosis Patients through Phase Contrast Magnetic Resonance Imaging.
http://www.ncbi.nlm.nih.gov/pubmed/25233279

Abstract
We studied cerebrospinal fluid (CSF) flow dynamics at the cervical level in association with internal jugular veins (IJV) flow for 92 patients with multiple sclerosis (MS). Phase contrast magnetic resonance imaging was used to quantify flow of the CSF and major vessels (including the IJV and the carotid arteries) at the C2-C3 level in the neck. Contrast enhanced MR angiography and time-of-flight MR venography were used to subdivide MS patients into stenotic (ST) and non-stenotic (NST) populations. We evaluated: IJV flow normalized by arterial flow; CSF peaks; CSF outflow duration and its onset from systole. We tested if these variables were statistically different among different MS phenotypes and between ST and NST MS patients. The delay between the beginning of beginning of systole and the CSF outflow was higher in ST compared to NST MS. Less IJV flow was observed in ST vs NST MS. None of the measures was different between the different MS phenotypes.

These results suggest that alterations of IJV morphology affect both IJV flow and CSF flow timing but not CSF flow amplitude.

[Cece]

The delay between the beginning of beginning of systole and the CSF outflow was higher in ST compared to NST MS. Less IJV flow was observed in ST vs NST MS. None of the measures was different between the different MS phenotypes.

These results suggest that alterations of IJV morphology affect both IJV flow and CSF flow timing but not CSF flow amplitude.

They're finding stenoses in some MS patients (not all) and in the patients with stenoses, they're finding that the stenosis has an effect on IJV flow and on CSF flow timing. It seems to be strong research and in support of the existence of CCSVI.

What does it mean that CSF timing is abnormal? How would that affect the brain? Timing but not amplitude. Does timing mean that it drains more slowly?

I am no longer surprised that there is no differences seen in the different MS phenotypes. I think CCSVI sets the stage but there are additional factors such as the immune response that can determine how MS is expressed.

[Rogan]

Is this as simple as described the power is the same but it is less often?


Or are they referring to wave vocab? Distance between peaks and frequency?

I have thought I believed perfusion was lower but I guess I didn't know what that meant?

I thought it was constricted flow? Less fluids to the brain?


Thanks in advance to those that understand this.

[1eye]

It seems like a complicated circuit.

Consider that the neck is the point where the sum of all inflows must equal the sum of all outflows. Considering only the blood part of the circuit, a stenosis would make the resistance to blood flow higher. Thus far I am only considering instantaneous, average, and not pulsatile flow. You would get the same average outflow only if you were able to push hard enough to make the average pressure high enough to overcome the higher resistance.

If you were not able to push harder (on average), the average flow rate would have to go down. This is possibly where perfusion would also go down. The capillary beds serve to average out the pulsatility of the blood flow. If perfusion has gone down, the oxygen uptake of the organs served by that perfusion would also have to be reduced.

So far, we have not considered pulsatile flows. We have also not considered the contribution of blood to or from the CSF flow.

Now with MRI we are able to also measure instantaneous flows. So we can see peaks and troughs in bloodflow. Presumeably, though I have only read the abstract, we can also measure instantaneous CSF flow. Thus:

The delay between the beginning of beginning of systole and the CSF outflow was higher in ST compared to NST MS. Less IJV flow was observed in ST vs NST MS.

I take this to mean that
a) there is a measureable delay between blood flow (beginning of systole) and CSF outflow
b) there is less IJV flow with a stenosis than without
c) the measureable [blood-inflow] -> [CSF-outflow] delay is higher with a stenosis than without.

It is also stated that there is less IJV flow in ST vs NST MS. Note that (a) this does not say the overall, average, outflow from the neck is less in ST vs NST "MS". It only refers to the IJV flow, which may be supplemented by other flows (spinal or corollary). This may or may not affect overall, average perfusion. If, however, there are fewer capillaries, because some have disappeared, then even if perfusion has not gone down, oxygen uptake may be reduced. If there is a lower perfusion rate and fewer capillaries, oxygen uptake will be even lower still. Perhaps these two problems combine to cause higher progression rates and disability. We probably don't have enough variables to distinguish phenotypes. It is likely there are other pathologies, which may or may not be caused by stenosis.

Without reading the whole paper I can't tell if there is more or less overall CSF flow, or if the outflow duration is always identical to the bloodflow duration. Then again, I know very little about CSF flow: what drives it, where does it flow, what functions of the brain depend on the flow(s), what is normal, and what is not. I am not surprised that there is a phase difference between blood and CSF cycles.

The abstract says:

IJV flow normalized by arterial flow; CSF peaks; CSF outflow duration and its onset from systole

This normalization may affect interpretation of the results, and I cannot tell much from the abstract alone (as usual).

In fact, if there is a tightly-coupled CSF circuit directly connected with the blood flow, it may be that changes in this will have as much or more effect on "MS" symptoms as does CCSVI itself.

[Robnl]

Indeed, i directly had to think about the fonar/dr damadian study, with 8 ms patients that had an early neck trauma. Remember? They had also a disturbed csf flow.