1. Division of Otolaryngology, Department of Surgery, University of Alabama at Birmingham School of Medicine, Birmingham, Alabama, United States
2. Department of Neurosurgery, University of Alabama at Birmingham School of Medicine, Birmingham, Alabama, United States
3. Department of Radiology, University of Alabama at Birmingham School of Medicine, Birmingham, Alabama, United States
4. Department of Otolaryngology, University of New South Wales, Sydney, Australia