Clinical cerebrovascular anatomy.

Stroke is often the result of carotid atheroma, which may cause ischemia via progressive arterial narrowing or lead to superimposed thrombus formation and subsequent atheroembolism to the intracerebral vasculature. Revascularization through carotid endarterectomy or carotid artery stenting with embolic protection devices has produced favorable results in appropriately selected patients. In planning the percutaneous approach, an arch aortogram is first acquired to determine arch type and identify the presence of any anatomic variants which may affect the approach to the procedure and catheter selection. Subsequent imaging of the cerebral vasculature is performed to delineate the collateral circulation that is present, including an evaluation of the Circle of Willis. Although Doppler ultrasound, computed tomography (CT), and magnetic resonance angiography (MRA) may be useful in evaluating the presence of carotid or cerebrovascular disease, digital subtraction angiography is required prior to performance of a percutaneous intervention in order to create a procedural "roadmap". Additionally, the comprehensive management of cerebrovascular disease requires a detailed knowledge of the specific clinical syndromes that result from ischemia in each vascular territory. This methodical review of cerebrovascular anatomy and stroke syndromes will provide the operator with the tools to conduct a thorough neurological assessment prior to revascularization, evaluate any periprocedural complications that may arise, and evaluate the patient with suspected stroke.