1. Division of Otolaryngology, Department of Surgery; University of Alabama at Birmingham; Birmingham Alabama U.S.A.
2. Otolaryngology-Head and Neck Surgery Department; Grenoble University Hospital; Grenoble France
3. Department of Surgery; Colombia Asia Referral Hospital; Yeshwanthpur Bangalore India
4. Division of Otolaryngology, Department of Special Surgery, Faculty of Medicine; Jordan University of Science and Technology; Irbid Jordan