Further to the story discussed at length at this blog here and here, Alberta Health Services has weighed in on the controversy surrounding Dr. Paolo Zamboni's controversial theory about MS and his proposed "liberation treatment". While some politicians are irresponsibly jumping the gun, Alberta Health Services is sounding a note of caution:
Patients with multiple sclerosis considering heading overseas for the much-hyped liberation treatment should speak with medical experts instead of relying on positive anecdotal evidence from fellow sufferers since the unproven procedure could cause severe medical problems, Alberta Health Services says.“People with MS should be wary about getting information solely from media stories and reports or from patients’ blogs,” the provincial health authority says in a strongly worded position paper on the subject, posted to its website. “Be careful about where you get information and where you go for treatment.”
The information sheet can be accessed directly here (PDF). Some highlights:
...Current information from Buffalo suggests that people with MS have a 56.4% chance of having CCSVI, and that those without MS have a 22.4% chance. In addition, over 40% of people with other neurological diseases have vascular changes consistent with CCSVI. However, other groups (Doepp et al, 2010 Annals of Neurology) have not found an increased rate of CCSVI in British and German people with MS as compared to “control” persons without MS. In contrast, Dr. Zamboni reported that 100% of the MS patients he studied had MS but none of his controls had CCSVI.(...)Generally speaking, and based on current evidence, neurologists and neuroscientists who are up-to-date about the biology of MS and vascular diseases of the brain do not believe that CCSVI will be proven to be a cause of MS. Nor do these experts believe there is likely to be any merit in venous angioplasty for CCSVI. They know that brain injury in MS is caused by the immune system and they are also familiar with vascular diseases that affect the brain (most
commonly stroke and conditions such as cerebral venous sinus thrombosis where the veins that drain the brain are blocked). Thus, neurologists care for people with MS and for people with neurological diseases caused or related to abnormal blood vessels, so they have the expertise to understand the association between the brain and its blood supply and venous drainage, and they are aware of the
consequences of blocked veins within the brain and/or the neck. They also know that MS or an MS-like condition has never been shown to be a result of blocked or sluggish veins.
If poor venous drainage from the brain were to cause MS, then people with blocked or absent jugular or vertebral veins should develop MS or an MS-like condition. There are many people with true venous insufficiency but they never get MS. In fact, neck surgeons commonly tie off one or both jugular veins during surgery to treat head and neck cancer; this has no medical consequence because the venous drainage of the head and brain is designed to have alternative routes of drainage.(...)Because arteries are thick walled and are designed to deal with high pressure, they can tolerate angioplasty. Because arteries carry blood away from the heart and get smaller as they get farther from the heart, a stent will only get properly secured into an artery by its high pressure blood flow.
Veins, on the other hand, are thin walled, collapse when not filled with blood, and do not tolerate injury well. Veins clot off permanently if repeatedly or severely injured.
Angioplasty purposely causes the veins to be stretched by a balloon. The veins commonly react by clotting and then
often become completely blocked. Similarly, stents will often clot, especially in the low pressure
flow seen in veins.(...)For this reason, there are no situations where venous angioplasty is an accepted and satisfactory treatment. This is very different than arterial angioplasty which is known to be useful. Therefore, the claims that venous angioplasty
is a “routinely done procedure” are not true.
Venous angioplasty is a procedure that needs to be properly evaluated in well designed clinical trials that determine both the risks and the benefits. However, given that we can be confident that many people will sustain completely occluded veins from the procedure, we must be very sure that there is enough evidence to suggest that CCSVI actually contributes to ongoing brain injury in MS before we undertake such trials. Patients considering leaving the country for this purported treatment should also consider this.(...)As of today, no Canadian neurologist has found significant or sustained improvement upon examination of patients
who had had venous angioplasty performed, despite the fact that most returning patients report feeling better and sometimes note improvement in sensation or walking.(...)People with MS should be wary about getting information solely from media stories and reports or from patient’s “blogs.” They should seek out expert advice from knowledgeable MS caregivers and experts, and should carefully determine the credentials of any centre offering “liberation” treatment.
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