1. Department of Otolaryngology-ENT, Faculty of Medicine, El Fayoum University, Cairo, Egypt
2. Lecturer of Radiodiagnosis, Faculty of Medicine, Zagazig University, Zagazig, Egypt
3. Rhinology and Endoscopic Fellowship Program, Department of Otolaryngology, University of Miami, Miller School of Medicine, Miami, Florida, United States
4. Department of Otolaryngology, Faculty of Medicine, Zagazig University, Zagazig, Egypt