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Underappreciated in the midst of these clashing positions is one other example of a similar venous lesion with potential relevance to MS – sheathing of retinal veins. This cuffing or sheathing of veins can be appreciated on fundoscopic examination of the eyes and may be associated with retinal vein thrombosis, optic neuritis and vision loss. In the majority of cases when it is diagnosed during an evaluation of disturbed vision, it occurs in patients with MS. Studied extensively at the Mayo Clinic, it is not however singularly associated with cases of established MS. Its frequency among MS patients is estimated to range from 11% to 42%. After fluoroscein dye administration, it is possible to observe leakage of dye around the retinal veins and histologically, the veins display a thickened wall similar to appearances observed in other chronically obstructed venous territories.

When contemplating the possible association between venous obstruction, blood-brain barrier leakage, myelin destruction and immune mechanisms responsible for the initiation of MS, it is interesting to note that the retinal nerve fibres are not myelinated in 99% of the population.

RETINAL VENOUS SHEATHING IN OPTIC NEURITIS
ITS SIGNIFICANCE FOR THE PATHOGENESIS OF MULTIPLE SCLEROSIS
S. LIGHTMAN, W. I. McDONALD1,2, A.C. BIRD1, D.A. FRANCIS2,3, A. HOSKINS1,J.R. BATCHOLER3 and A.M. HALLIDAY2
The occurrence of perivenular abnormalities in a region free of myclin and oligodendrocytes provides evidence that the vascular changes in MS can occur independently of contiguous demyelination, and may be the primary event in the formation of a new lesion.

Everything suggests that the presence of retinal abnormalities, whenever these may have occurred with respect to the recent onset of optic neuritis, carries the same significance for subsequent clinical conversion as does clinical or laboratory evidence for a lesion outside the visual system; and the retinal vascular abnormalities indicate that the pathological process underling demyelination of the CNS is already active during this inaugural event.

MSBOB wrote: Backing up a little, those vessels coming in and out of the eyes are also the same viens responsible for signaling the muscles in the jugulars to speed up or slow down the blood flow to the head. That there is a lot to think about.

Thanks for the friendly conversation and the new links.

cheerleader wrote:Dr. Dake made a very important point for the CIRSE conference with his in depth essay on the importance of CCSVI research.

Retinal Vein Sheathing in MS-- the veins of the retina in pwMS become enlarged and thickened and there is damage to the retinal nerves. Without myelin. Again, there is no myelin on retinal nerves, but there is immune activation. The optic nerve, which exits the back of the eyeball, does have myelin. The retinal nerve sheath, inside the eyeball, does not.

Here's Dr. Dake---

Underappreciated in the midst of these clashing positions is one other example of a similar venous lesion with potential relevance to MS – sheathing of retinal veins. This cuffing or sheathing of veins can be appreciated on fundoscopic examination of the eyes and may be associated with retinal vein thrombosis, optic neuritis and vision loss. In the majority of cases when it is diagnosed during an evaluation of disturbed vision, it occurs in patients with MS. Studied extensively at the Mayo Clinic, it is not however singularly associated with cases of established MS. Its frequency among MS patients is estimated to range from 11% to 42%. After fluoroscein dye administration, it is possible to observe leakage of dye around the retinal veins and histologically, the veins display a thickened wall similar to appearances observed in other chronically obstructed venous territories.

When contemplating the possible association between venous obstruction, blood-brain barrier leakage, myelin destruction and immune mechanisms responsible for the initiation of MS, it is interesting to note that the retinal nerve fibres are not myelinated in 99% of the population.

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Lesions that look like MS lesions, occuring on nerves that do not have myelin. Leaking veins....in people who develop MS. "Cuffs" that contain immune cells around these leaking veins.

RETINAL VENOUS SHEATHING IN OPTIC NEURITIS
ITS SIGNIFICANCE FOR THE PATHOGENESIS OF MULTIPLE SCLEROSIS
S. LIGHTMAN, W. I. McDONALD1,2, A.C. BIRD1, D.A. FRANCIS2,3, A. HOSKINS1,J.R. BATCHOLER3 and A.M. HALLIDAY2
The occurrence of perivenular abnormalities in a region free of myclin and oligodendrocytes provides evidence that the vascular changes in MS can occur independently of contiguous demyelination, and may be the primary event in the formation of a new lesion.

http://brain.oxfordjournals.org/content ... 5.abstract
cheer

cheerleader wrote:After fluoroscein dye administration, it is possible to observe leakage of dye around the retinal veins and histologically, the veins display a thickened wall similar to appearances observed in other chronically obstructed venous territories.

Cece wrote:
Do the retina veins actually look completely normal again once they've had a chance to heal after CCSVI syndrome has been treated?

A Johns Hopkins-based study of a group of 40 multiple sclerosis (MS) patients used a process called optical coherence tomography (OCT) to scan the layers of nerve fibers of the retina in the back of the eye, which become the optic nerve. The process, which uses a desktop machine similar to a slit-lamp, is simple and painless. The retinal nerve fiber layer is the one part of the brain where nerve cells are not covered with the fat and protein sheathing called myelin, making this assessment specific for nerve damage as opposed to brain MRI changes, which reflect an array of different types of tissue processes in the brain.

Results of the scans were calibrated using accepted norms for retinal fiber thickness and then compared to an MRI of each of the patient's brains - also calibrated using accepted norms. Experimenters found a correlation coefficient of 0.46, after accounting for age differences. Correlation coefficients represent how closely two variables are related -- in this case MRI of the brain and OCT scans. Correlation coefficients range from -1 (a perfect opposing correlation) through 0 (no correlation) to +1 (a perfect positive correlation). In a subset of patients with relapsing remitting MS, the most common form of the disease, the correlation coefficient jumped to 0.69, suggesting an even stronger association between the retinal measurement and brain atrophy.

“This is an encouraging result,” says Johns Hopkins neurologist Peter Calabresi, M.D., lead author of the study, which appears in the October 2007 issue of Neurology. “MRI is an imperfect tool that measures the result of many types of tissue loss rather than specifically nerve damage itself. With OCT we can see exactly how healthy these nerves are, potentially in advance of other symptoms.”

I now see value in having a paradigm in which to study the vascular impacts of MS

I think obstruction and inflammation of the vascular offer another checken or egg scenario.

MSBOB wrote:White blood cells can't pass the blood brain barrier, and are not native to the CNS.

MSBOB wrote:Then later, the white blood cells have the duel purposes of cleanup and repair.

MrSuccess wrote:good exchange of ideas and information . As you know , there has been a long held view that -trauma - has been long suspected as the trigger for MS. I suspect that X % of children born ..... suffer some form of neck trauma , in the birthing process.

If you have ever witnessed forcep deliveries ...... you might agree with this point of view.


Has anyone done followup study's on children delivered by the forcep method ?

I do wonder how many go on to have CCSVI ..... then ..... MS.



Mr.Success