Here's NPH-I have seen this happen in “normal pressure hydrocephalus- (NPH) Where there is a loss of gait, cognitive and bladder issues and the lesions disappear because the expanded ventricle swallows the lesion. I have shunted the brains of NPH patients, and they showed remarkable improvements. Again, the enlargement of the third ventricle precedes the changes.
We know that hydrocephalus can occur due to jugular stenosis or blockage. This is well documented in Crouzon's and jugular foramen stenosis....but the hydrocephalus is REALLY apparent. In normal pressure hydrocephalus, it takes longer to cause damage, because it is a slower process. So...I took it from here to look in to why some more progressive folks might be having restenosis after stenting...PERHAPS the CSF excess pressure is not relieved enough by merely opening the jugulars, restenosis can form. I have sent the following research to Dr. Dake-The brain and spinal cord are surrounded by a clear fluid called cerebrospinal fluid (CSF). This fluid is produced and stored in cavities in the brain called ventricles. It circulates around the brain, moving from ventricle to ventricle. The purposes of the fluid are to cushion and protect the brain and spinal cord, to supply them with nutrients, and to remove some of their waste products. Any excess fluid drains away from the brain and is absorbed by other tissues.
Hydrocephalus is a condition in which there is too much CSF in the ventricles. This occurs when the natural system for draining and absorbing extra CSF does not work right. The ventricles enlarge to accommodate the extra fluid and then press on different parts of the brain, causing a number of different symptoms. Hydrocephalus has many different causes. Some people are born with the condition, while others develop it during their lives.
Normal pressure hydrocephalus (NPH) is a type of hydrocephalus that occurs in adults, usually older adults. The average age of people with NPH is older than 60 years. NPH is different than other types of hydrocephalus in that it develops slowly over time. The drainage of CSF is blocked gradually, and the excess fluid builds up slowly. The slow enlargement of the ventricles means that the fluid pressure in the brain may not be as high as in other types of hydrocephalus. However, the enlarged ventricles still press on the brain and can cause symptoms. (The term "normal pressure" is somewhat misleading.)
http://www.ajnr.org/cgi/content/full/28/4/656
If you're still following me here...this is the thought....maybe in most individuals (like my Jeff), it is the stenosis causing the CSF level changes, and resolving the stenosis takes care of it....BUT maybe in some folks, like our dear skydog....it is the CSF levels causing the stenosis, and relieving the stenosis in one place only creates restenosis somewhere else, because the CSF issue is not resolved.By definition, in secondary intracranial hypertension (SIH), there is an underlying medical condition, whereas in IIH, the cause is not known. In many cases of SIH, an increased cerebral venous pressure raises the intracranial pressure as in dural venous fistulas, venous sinus thrombosis, or venous sinus compression.1 However, in almost all patients with IIH (and also in our patients), neuroimaging shows narrowing of the transverse sinuses,2,3,5–7 not reflecting acute thrombosis. The important question is whether those venous abnormalities are cause or consequence of increased intracranial pressure. In the former situation, fixed stenoses (for example postthrombotic fibrotic changes) could obstruct the venous outflow, increase intracranial venous pressure proximal to the stenosis, and lead to increased CSF pressure as a result of a reduction in CSF absorption via the arachnoid granulations. In this setting, a pressure gradient across the stenosis should be measured and reconstruction of the venous lumen with endovascular stents would be effective in lowering elevated CSF pressure. This procedure was successfully used several times4,6 but seems not to be efficient in all patients.6 In the latter (ie, venous abnormalities as a consequence of intracranial pressure), elevated intracranial CSF pressure could lead to a secondary narrowing of the sinus lumen by compression, which can be reversed by lumbar puncture or shunt surgery procedures.5,7,8 In fixed stenoses (the 1st model), therapeutic reduction of CSF pressure should have no effect on sinus diameter.
We'll see what Dr. D says on this, or if my thinking is wrong. THIS IS WHY WE NEED NEUROS WORKING WITH VASCULAR DOCS TOGETHER...
cheer