R Sawaya1, W Radwan2, R Alameddine3, S Hammoud2. 1. Department of Neurology, American University Medical Center, Beirut, Lebanon. Electronic address: rs01@aub.edu.lb. 2. Department of Neurology, American University Medical Center, Beirut, Lebanon. 3. Department of Ophthalmology, American University Medical Center, Beirut, Lebanon.