A Method for Quantifying Angiographic Severity of Extracranial Vertebral Artery Stenosis.

Vertebral artery origin stenosis is a common occurrence among patients with ischemic events in the vertebral and basilar arterial distribution [1,2]. Of the 407 patients in the New England Medical Center Posterior Circulation Registry, 80 (20%) of patients with ischemic events in the vertebral and basilar arterial distribution had vertebral artery origin occlusion or high-grade stenosis [1]. Treatment options for vertebral artery origin occlusion or high-grade stenosis associated with ischemic events, include medical therapy, angioplasty and stent placement, and open surgical revascularization procedures. Aggressive medical therapy may or may not be effective for the reduction of cerebral ischemic events among patients with symptoms caused by hemodynamic impairment from vertebral artery origin occlusion or high-grade stenosis [3]. Stent placement is a treatment option for patients with extracranial vertebral artery stenosis when patients are having symptoms despite optimal medical treatment (Class IIb; Level of Evidence C) [3].