Sponsor: NINDS

Principle Investigator: Randolph S. Marshall, MS, MD, Columbia University Medical Center, Department of Neurology

This NIH-sponsored clinical trial is an ancillary study to the Carotid Occlusion Surgery Study (COSS). The goal of RECON is to assess the relationship between cerebral blood flow and cognitive function in patients undergoing treatment for unilateral carotid artery occlusion with extracranial-intracranial (EC-IC) bypass in COSS. Patients undergo a 1-hour neurocognitive test at the beginning of the trial and at the 2-year follow up point to test the hypothesis that EC-IC bypass will improve or preserve cognitive function.