[1] Policlin Univ Campus Biomed Roma, UOS Cefalee & Neurosonol, Via Alvaro Portillo 200, I-00128 Rome, Italy
[2] Fdn Fatebenefratelli Ric & Formaz Sanitaria & Soc, Serv Stat Med, Rome, Italy
[3] Univ Bologna, IRCCS Ist Sci Neurol Bologna, DIBINEM, Alma Mater Studiorum, Bologna, Italy
[4] Ist Neurol Carlo Besta, Milan, Italy