Patients who have suffered from stroke and receive carotid bypass surgery - which improves blood flow to the brain - see no overall improvement in cognitive performance, researchers informed at The American Stroke Association's International Stroke Conference 2013.

http://www.medicalnewstoday.com/articles/256136.php


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Among participants with recently symptomatic atherosclerotic internal carotid artery occlusion (AICAO) and hemodynamic cerebral ischemia, extracranial-intracranial (EC-IC) bypass surgery plus medical therapy compared with medical therapy alone did not reduce the risk of recurrent ipsilateral ischemic stroke at 2 years.

http://jama.jamanetwork.com/article.aspx?articleid=1104607