[1] St Michaels Hosp, Div Vasc Surg, Toronto, ON M5B 1W8, Canada
[2] Unity Hlth Toronto, St Michaels Hosp, Li Ka Shing Knowledge Inst, Toronto, ON M5B 1W8, Canada
[3] Univ Toronto, Dept Med, Div Neurol, Toronto, ON M5S 1A1, Canada
[4] Univ Toronto, Dept Surg, Toronto, ON M5T 1P5, Canada