1. College of Medicine, King Saud University, Riyadh, Saudi Arabia
2. Department of Otolaryngology – Head & Neck Surgery, College of Medicine, King Saud University, Riyadh, Saudi Arabia
3. Department of Surgery, Unit of Otolaryngology – Head & Neck Surgery, Security Forces Hospital Program, Riyadh, Saudi Arabia
4. Otolaryngology – Head & Neck Surgery Unit, Surgery Department, Security Forces Hospital Program, Riyadh, Saudi Arabia