The evidence for cerebral protection: an analysis and summary of the literature.

It has been considered likely that the majority of cerebral ischaemic episodes following carotid artery stenting are due to cerebral embolisation. It is intuitive therefore, to attempt to prevent these presumptive emboli, whether they are comprised of air or formed elements, from reaching the brain. Various pharmacological and mechanical solutions are being used. The available literature is hampered by comparisons against historical controls of unprotected CAS with many confounding variables that may influence outcome. There is no clinical Level-I evidence to support the use of protection devices but Level-III and Level-IV evidence suggest benefit.