Extracranial-intracranial bypass for cerebral ischaemia

Symptomatic stenosis or occlusion of the cervical (C1) internal carotid artery (ICA) is best addressed surgically with direct endarterectomy or thrombectomy procedures. This strategy is not usually possible for more distal lesions, and restoring brain perfusion requires diversion of blood from the extracranial to intracranial circulation with a variety of indirect and direct bypass techniques. However, despite five decades of experience and technical refinement, extracranial-intracranial (EC-IC) bypass for cerebral ischaemia remains contentious. This chapter looks at the conflicting bodies of evidence and opinion regarding how best to select patients for surgery, and asks whether there is meaningful clinical benefit with the surgical options available.