RT Journal Article SR Electronic T1 Collateral flow as causative of good outcomes in endovascular stroke therapy JF Journal of NeuroInterventional Surgery JO J NeuroIntervent Surg FD BMJ Publishing Group Ltd. SP 2 OP 7 DO 10.1136/neurintsurg-2014-011438 VO 8 IS 1 A1 Sheth, Sunil A A1 Sanossian, Nerses A1 Hao, Qing A1 Starkman, Sidney A1 Ali, Latisha K A1 Kim, Doojin A1 Gonzalez, Nestor R A1 Tateshima, Satoshi A1 Jahan, Reza A1 Duckwiler, Gary R A1 Saver, Jeffrey L A1 Vinuela, Fernando A1 Liebeskind, David S A1 for the UCLA Collateral Investigators YR 2016 UL http://jnis.bmj.com/content/8/1/2.abstract AB Background Endovascular reperfusion techniques are a promising intervention for acute ischemic stroke (AIS). Prior studies have identified markers of initial injury (arrival NIH stroke scale (NIHSS) or infarct volume) as predictive of outcome after these procedures. We sought to define the role of collateral flow at the time of presentation in determining the extent of initial ischemic injury and its influence on final outcome.Methods Demographic, clinical, laboratory, and radiographic data were prospectively collected on a consecutive cohort of patients who received endovascular therapy for acute cerebral ischemia at a single tertiary referral center from September 2004 to August 2010.Results Higher collateral grade as assessed by the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) grading scheme on angiography at the time of presentation was associated with improved reperfusion rates after endovascular intervention, decreased post-procedural hemorrhage, smaller infarcts on presentation and discharge, as well as improved neurological function on arrival to the hospital, discharge, and 90 days later. Patients matched by vessel occlusion, age, and time of onset demonstrated smaller strokes on presentation and better functional and radiographic outcome if found to have superior collateral flow. In multivariate analysis, lower collateral grade independently predicted higher NIHSS on arrival.Conclusions Improved collateral flow in patients with AIS undergoing endovascular therapy was associated with improved radiographic and clinical outcomes. Independent of age, vessel occlusion and time, in patients with comparable ischemic burdens, changes in collateral grade alone led to significant differences in initial stroke severity as well as ultimate clinical outcome.