Intracranial arterial stenoses: current viewpoints, novel approaches, and surgical perspectives

Neurosurg Rev. 2013 Apr;36(2):175-84; discussion 184-5. doi: 10.1007/s10143-012-0432-z. Epub 2012 Oct 25.

Abstract

Ten percent of all strokes occurring in the USA are caused by intracranial arterial stenosis (IAS). Symptomatic IAS carries one of the highest rates of recurrent stroke despite intensive medical therapy (25 % in high-risk groups). Clinical results for endovascular angioplasty and stenting have been disappointing. The objectives of this study were to review the contemporary understanding of symptomatic IAS and present potential alternative treatments to resolve factors not addressed by current therapies. We performed a literature review on IAS pathophysiology, natural history, and current treatment. We present an evaluation of the currently deficient aspects in its treatment and explore the role of alternative surgical approaches. There is a well-documented interrelation between hemodynamic and embolic factors in cerebral ischemia caused by IAS. Despite the effectiveness of medical therapy, hemodynamic factors are not addressed satisfactorily by medications alone. Collateral circulation and severity of stenosis are the strongest predictors of risk for stroke and death. Indirect revascularization techniques, such as encephaloduroarteriosynangiosis, offer an alternative treatment to enhance collateral circulation while minimizing risk of hemorrhage associated with hyperemia and endovascular manipulation, with promising results in preliminary studies on chronic cerebrovascular occlusive disease. Despite improvements in medical management for IAS, relevant aspects of its pathophysiology are not resolved by medical treatment alone, such as poor collateral circulation. Surgical indirect revascularization can improve collateral circulation and play a role in the treatment of this condition. Further formal evaluation of indirect revascularization for IAS is a logical and worthy step in the development of intracranial atherosclerosis treatment strategies.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Cerebral Arterial Diseases / surgery*
  • Cerebral Arteries / surgery*
  • Collateral Circulation
  • Constriction, Pathologic
  • Endovascular Procedures / methods*
  • Humans
  • Intracranial Arteriosclerosis / epidemiology
  • Intracranial Arteriosclerosis / surgery
  • Ischemic Attack, Transient / epidemiology
  • Ischemic Attack, Transient / physiopathology
  • Ischemic Attack, Transient / surgery*
  • Neovascularization, Physiologic / physiology
  • Neurosurgical Procedures / methods*
  • Stroke / epidemiology
  • Stroke / physiopathology
  • Stroke / surgery*