Selective treatment of external carotid artery stenosis

摘要

The relevance of the extracranial-to-intracrani-al (EC IC) collateral circulation has been a matter of debate for a long time. In vivo experimental settings mimicking internal carotid artery (ICA) occlusion suggested a contribution of the external carotid artery (ECA) in up to 15% of middle cerebral artery blood flow.1 In various other studies on patients with unilateral ICA occlusion, the role of leptomeningeal anastomoses and alternative cerebropetal arteries was established, revealing retrograde flow in the ophthalmic artery in 36% to 89% of cases,2 while focal brain regions may angio-graphically depend strongly on ipsilateral ECA contribution.3 Until now, no benefit of any type of ECA revascularization in symptomatic patients has been established over conservative best medical treatment in terms of stroke prevention and postprocedural increase in cerebral perfusion.