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Skull Base 2005; 15(1): 43-62
DOI: 10.1055/s-2005-868162
Copyright © 2005 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA.

Revascularization of the Posterior Circulation

Bert A. Coert1 , 3 , 4 , Steven D. Chang1 , 3 , 4 , Michael P. Marks1 , 2 , 3 , 4 , Gary K. Steinberg1 , 3 , 4
  • 1Departments of Neurosurgery, Stanford University School of Medicine, Stanford, California
  • 2Departments of Radiology, Stanford University School of Medicine, Stanford, California
  • 3Departments of Stanford Stroke Center, Stanford University School of Medicine, Stanford, California
  • 4Departments of Neuroscience Institute at Stanford, Stanford University School of Medicine, Stanford, California
Further Information

Publication History

Publication Date:
14 April 2005 (online)

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The primary objective of revascularization procedures in the posterior circulation is the prevention of vertebrobasilar ischemic stroke. Specific anatomical and neurophysiologic characteristics such as posterior communicating artery size affect the susceptibility to ischemia. Current indications for revascularization include symptomatic vertebrobasilar ischemia refractory to medical therapy and ischemia caused by parent vessel occlusion as treatment for complex aneurysms. Treatment options include endovascular angioplasty and stenting, surgical endarterectomy, arterial reimplantation, extracranial-to-intracranial anastomosis, and indirect bypasses. Pretreatment studies including cerebral blood flow measurements with assessment of hemodynamic reserve can affect treatment decisions. Careful blood pressure regulation, neurophysiologic monitoring, and neuroprotective measures such as mild brain hypothermia can help minimize the risks of intervention. Microscope, microinstruments and intraoperative Doppler are routinely used. The superficial temporal artery, occipital artery, and external carotid artery can be used to augment blood flow to the superior cerebellar artery, posterior cerebral artery, posterior inferior cerebellar artery, or anterior inferior cerebellar artery. Interposition venous or arterial grafts can be used to increase length. Several published series report improvement or relief of symptoms in 60 to 100% of patients with a reduction of risk of future stroke and low complication rates.

KEYWORDS

Vertebrobasilar ischemia - angioplasty - parent vessel occlusion - bypass - revascularization

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Gary K SteinbergM.D. Ph.D. 

Department of Neurosurgery, Stanford University School of Medicine

300 Pasteur Dr., Rm. R281

Stanford, CA, 94304-5327

Email: gsteinberg@stanford.edu

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