The combined analysis by Rothwell et al369 of CEA in patients with recent stroke or TIA found no ben- efit in patients with <50% ICA stenosis. 12. In COSS (Carotid Occlusion Surgery Study), 195 subjects with recently symptomatic carotid occlu- sion and increased oxygen extraction fraction measured by positron emission tomography were assigned to bypass surgery or medical therapy.377 The primary end point was stroke/death within 30 days and ipsilateral stroke up to 2 years. The pri- mary end point occurred in 21.0% of the surgery group and 22.7% of the medically treated patients (P=0.78). This supports the recommendation against bypass surgery for patients with recently symptomatic carotid occlusion. 5.1.2.2. Extracranial Vertebral Artery Stenosis Recommendations for Extracranial Vertebral Artery Stenosis Referenced studies that support recommendations are summarized in online Data Supplement 28. COR LOE Recommendations In patients with recently symptomatic extra- cranial vertebral artery stenosis, intensive medical therapy (antiplatelet therapy, lipid lowering, BP control) is recommended to reduce stroke risk.378 In patients with ischemic stroke or TIA and extracranial vertebral artery stenosis who are having symptoms despite optimal medical treatment, the usefulness of stenting is not In patients with ischemic stroke or TIA and extracranial vertebral artery stenosis who are having symptoms despite optimal medical treatment, the usefulness of open surgical procedures, including vertebral endarterec- tomy and vertebral artery transposition, is not well established. Synopsis Extracranial vertebral artery stenosis is thought to account for 10% of posterior circulation strokes. Revas- cularization procedures are not performed often for ver- tebral artery stenosis. Small trials (VAST, VIST) did not show a clear benefit for vertebral artery stenting, and a recent combined analysis also did not demonstrate clear benefit for vertebral artery stenting compared with medical therapy. Recommendation-Specific Supportive Text 1. 