Marco Giulioni1, Matteo Martinoni2, Gianluca Marucci3. 1. IRCCS Institute of Neurological Sciences, Section of Neurosurgery, Bellaria Hospital, Bologna, Italy. Electronic address: giulioni.m@tiscali.it. 2. IRCCS Institute of Neurological Sciences, Section of Neurosurgery, Bellaria Hospital, Bologna, Italy. 3. Department of Biomedical and NeuroMotor Sciences (DiBiNeM), Section of Pathology, Bellaria Hospital, Bologna, Italy.