1. King Fahad Medical City, MOH, As Sulimaniyah, Riyadh 12231, Saudi Arabia
2. King Abdullah International Medical Research Center, King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, National Guard Health Affairs, Riyadh 11481, Saudi Arabia
3. Division of Neurology, Department of Medicine, Amiri Hospital, Gulf Road, Bin Misbah St, Sharq, Kuwait
4. Department of Neuroscience, King Faisal Specialist Hospital and Research Centre, Al Rawdah Street, Jeddah, Saudi Arabia
5. Neurology Department, King Faisal Specialist Hospital, Zahrawi St, Riyadh 12713, Saudi Arabia
6. Neurology Department, King Khalid University Hospital, Riyadh 12372 6864, Saudi Arabia
7. Neurology Department, Herrah General Hospital, Makkah 20993, Saudi Arabia
8. Neurology Department, King Fahad Specialist Hospital, Ammar Bin Thabit St, Al Merikbat Neighborhood, Dammam 32253, Saudi Arabia
9. Neurology Department, Cairo University Hospital, Old Cairo, Cairo Governorate, Egypt
10. Neurology Department, Faculty of Medicine, Ain Shams University, El-Khalyfa El-Mamoun St, El-Abaseya, Egypt
11. Habib Bourguiba Hospital, Rue Al Firdaws, 3029 Sfax, Tunisia
12. Razi Hospital, 1st Street Ovanges, 2010 Manouba, Tunisia
13. Merck Serono, Tahaliyah St, 502 Jameel Square, Jeddah, Saudi Arabia, An Affiliate of Merck KGaA, Darmstadt, Germany