[1] Yale Sch Med, Div Neurocrit Care & Emergency Neurol, New Haven, CT 06510 USA
[2] Yale Sch Med, Dept Neurol, New Haven, CT USA
[3] Frank HNetter MD Sch Med, North Haven, CT USA
[4] Yale Sch Med, Dept Neurol, Div Vasc Neurol, New Haven, CT USA
[5] Yale Sch Med, Dept Internal Med, New Haven, CT USA