1. Division of Neurology, Amiri Hospital, Qurtoba 73767, Kuwait
2. Division of Neurology, Dasman Diabetes Institute, P.O. Box 1180, Dasman 15462, Kuwait
3. Department of Neurology, Ibn Sina Hospital, P.O. Box 25427, Safat 13115, Kuwait
4. Department of Medicine, Kuwait University, P.O. Box 24923, Safat 13110, Kuwait
5. Department of Neurology and Psychiatry, Minia University, P.O. Box 61519, Minia 61111, Egypt