1. General Medicine Department , Faculty of Medicine, , Damascus 963 , Syria
2. Damascus University , Faculty of Medicine, , Damascus 963 , Syria
3. General Surgery Department, Maarib General Hospital Authority , Maarib 967 , Yemen
4. General Surgery Department, Pavol Jozef Safarik University , Kosice , Slovakia
5. Department of Otolaryngology – Head and Neck Surgery , Al-Mouwasat University Hospital, Faculty of Medicine, , Damascus 963 , Syria
6. Damascus University , Al-Mouwasat University Hospital, Faculty of Medicine, , Damascus 963 , Syria
7. General Medicine Department , Faculty of Medicine, , Damascus 967 , Syria
8. Syrian Private University , Faculty of Medicine, , Damascus 967 , Syria