Dr. Middleton; have you ever seen a vertebral artery that has an adhesion to the cranium as it passes through the Foramen Magnum? I've seen evidence on CT that their is some kind of membranous "coating" that continues from the surface of the Foramen Magnum, and appears to "encapsulate" the VA for about 1-1.5 cm... If this is an adhesion, it's likely to constrain free movement of the VA during rotation or extension, which would correlate with a central vertigo that occurs while standing, with neck extension... The symptoms look like VBI, and their appears to be symptoms of SIH/CSF leak, as well...
