1. Department of Ophthalmology and Visual Sciences, McGill University Health Center, Montreal, Canada
2. Neuro-ophthalmology Unit, Albahar Ophthalmology Center, Ibn Sina Hospital, Shuwaikh, Kuwait
3. Royal Eye Unit, Kingston Hospital Foundation Trust, London, UK
4. Neuro-ophthalmology Department, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia