1. Department of Otolaryngology–Head and Neck Surgery Mayo Clinic Rochester Minnesota USA
2. Department of Quantitative Health Sciences Mayo Clinic Rochester Minnesota USA
3. Department of Laboratory Medicine and Pathology, Division of Anatomic Pathology Mayo Clinic Rochester Minnesota USA
4. Department of Otolaryngology–Head and Neck Surgery University of Pittsburgh Pittsburgh Pennsylvania USA
5. Department of Neurological Surgery University of Pittsburgh Pittsburgh Pennsylvania USA