1 From the Department of Neurology (C.H.G.), Beth Israel Deaconess Medical Center, Boston, MA; and Department of Neurology (C.K.), Mayo Clinic, Rochester, MN. cgibbons@bidmc.harvard.edu.
2 From the Department of Neurology (C.H.G.), Beth Israel Deaconess Medical Center, Boston, MA; and Department of Neurology (C.K.), Mayo Clinic, Rochester, MN.