In case you missed this earlier question:
Almost all of these narrowings occur near the confluens of the jugular vein with the subcclavian where valves are seen normally in about 85 per cent of patients. Problem is these valves are highly dysfunctionally developed in patients with MS. I think the IVUS really shows this really well.The venogram shows narrowing but the IVUS shows that the narrowing is valvular.
These narrowings are not inflammatory strictures and they are not "buildup of tissue on the wall of the vein (sort of like plaqeu).
How do you determine that the narrowings are not caused inflammation?
Dr. Zamboni told us at the McMasters meeting a few months ago that pathology of the veins did not show inflammation.