Department of Neurology;
the Third Affiliated Hospital of Sun Yat-Sen University;
Guangzhou 510630;
Guangdong Province;
China;
Department of Neurology;
the Municipal Hospital of Qingdao;
Qingdao 266071;
Shandong Province;
China;
Department of Neurology;
the Affiliated Hospital of Qingdao University;
Qingdao 266003;
Shandong Province;
China;