Medscape vertebral artery dissection tear in the vertebral artery arterial dissection http://emedicine.medscape.com/article/761451-overview tear in the vertebral artery Vertebral Artery Dissection http://emedicine.medscape.com/article/761451-overview Vertebral Artery Dissection Vertebral Artery Dissection Medscape http://emedicine.medscape.com/article/761451-overview vertebral artery dissection vertebral artery dissection,