when does natural variance end and abnormality begin

[Cece]

http://www.medscape.com/viewarticle/826467

"Perhaps the most striking finding in our study was the range of venous outflow anomalies detected that did not reflect pathology, but instead demonstrated the large natural variance in intracranial and extra-cranial venous anatomy," write the authors, led by Fiona Costello, MD, Department of Clinical Neurosciences and Surgery and the Hotchkiss Brain Institute, University of Calgary, Alberta, Canada.

[1eye]

Oh, Fiona. My former eye-doctor. Yup. I guess those astronauts and us MS patients are just too normal.

[MarkW]

http://www.medscape.com/viewarticle/826467

"Perhaps the most striking finding in our study was the range of venous outflow anomalies detected that did not reflect pathology, but instead demonstrated the large natural variance in intracranial and extra-cranial venous anatomy," write the authors, led by Fiona Costello, MD, Department of Clinical Neurosciences and Surgery and the Hotchkiss Brain Institute, University of Calgary, Alberta, Canada.

Hello Cece,
The answer to the question is that they overlap:
"when does natural variance end and abnormality begin"
What causes a problem in one human does not cause the same problem in another.
Think about smoking causing cancer. Some people who smoke get cancer, others smoke 60 a day for 50 years without any sign of cancer. Its called population variation and even Neuros in Alberta should be aware of it. However they just want to make an anti CCSVI point.
MarkW

[cheerleader]

Great point, Mark--thanks!
I'd also point out that many "normal" people have white matter lesions on MRI---but they do not impact brain function in normal individuals. Why? Does this mean white matter lesions are inconsequential? Obviously not. Again--population variance. We know about this when considering nutritional needs for individuals.

There are many sources of this type of variability. The ones most commonly considered in setting recommendations are the following: age and gender; life stage [puberty, menopause, reproductive status (pregnant or lactating)]; body size; lifestyle; medical history; and genetic susceptibility

http://jn.nutrition.org/content/131/2/361S.full

Just because we do not understand something doesn't negate its importance.
cheer

[AMcG]

This is one of the studies which was 'rushed' into being in 2009 to defuse the CCSVI controversy. It is a very poor design which found nothing and looks very much as if it was designed to find nothing. The same as Traboulsee's study. It merely promotes it's failure to find anything significant as a 'negative' result for CCSVI rather than criticism of it's own poor design. If you really want to refute Zamboni you must first develop a technique of reliably replicating Zamboni's results and then show convincing evidence why his interpretation of those results is flawed. Just attempting to use his 2009 criteria (which are acknowledged as fallible and no one uses anymore) and failing to find anything proves nothing.

I really believe opposing Zamboni's ideas is an honourable scientific path worth pursuing. Science advances by the effects of conflicting ideas. We need naysayers just as much as yeasayers, So attempts to refute Zamboni are welcome. But you have to do a better job than this. Why would anyone consider this is serious science? It looks like a piss-take why would we think it is anything else?

I think this proves the MS Society's strategy of 'rushed' five year research is as daft as coupling 'rushed' with 'five years' suggests.