1 Neurology, Public Health and Disability Unit, Fondazione IRCSS Istituto Neurologico Carlo Besta, 20133 Milan, Italy. Electronic address: silvia.schiavolin@istituto-besta.it.
2 Division of Neurosurgery II, Fondazione IRCSS Istituto Neurologico Carlo Besta, 20133 Milan, Italy.
3 Neurology, Public Health and Disability Unit, Fondazione IRCSS Istituto Neurologico Carlo Besta, 20133 Milan, Italy.