1. Department of Otolaryngology, China–Japan Friendship Hospital, Beijing, People's Republic of China
2. Department of Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
3. Division of Otolaryngology and Head–Neck Surgery, Department of Surgery, Albany Medical Center, Albany, New York, United States
4. Department of Neurosurgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
5. Department of Neurosurgery, Stanford University, Stanford, California, United States