Abstract 179: International Survey of Clinical Case Vignettes in Acute Ischemic Stroke

Background and Purpose: To quantify consistency across stroke centers worldwide in the typical imaging and treatment decisions made when presented with independent clinical case vignettes including various imaging findings across specific time from onset intervals. Methods: Stroke Imaging Repository (STIR) and Virtual International Stroke Trials Archive (VISTA)-Imaging circulated an online survey of clinical case vignettes through its website, through the websites of national professional societies from multiple countries as well as through email distribution lists from STIR and participating societies. Vignettes varied in terms of patient’s age, time from onset, neurological symptoms and NIHSS. The survey displayed the imaging findings offered by the imaging strategy selected, and the responders selected the appropriate therapy considering time from onset, clinical presentation and imaging findings. Results: We received responses from 30 countries including 260 centers. The specific onset interval presented: 0-3 hours, 6 hours, 10 hours or wake-up, influenced the type of imaging work-up selected rather than the clinical scenario. CT was used more often than MRI across all time intervals. For cases with M1 occlusion and large penumbra, vascular imaging was most common (36%) in 0-3 hours and perfusion imaging more frequently used in 6 hours (62%) and wake-up stroke (65%). For large penumbra cases with M1 or ICA occlusion, combination, IV tPA thrombolysis followed by endovascularIA, treatment (81%) was most common in 0-3 hours. Endovascular treatment was selected the most at 6 hours (43%) for M1 occlusion and large penumbra cases but still selected in 27% of patients up to 10 hours for ICA occlusion and large penumbra cases. For M1 occlusion and large penumbra cases imaged with MRI only, treatment of wake-up stroke increased to 89% from 58% cases imaged with CT alone. Sites that obtained more imaging tended to be more aggressive in terms of revascularization treatment, particularly endovascular therapy. Conclusions: Adding vascular andor perfusion imaging increased the likelihood of thrombolysis across all time intervals. Usage of MRI perfusion imaging was associated with an increased likelihood of enrollment into a randomized trial up to 83%.