1. Department of Otorhinolaryngology-Head and Neck Surgery; University of Pennsylvania; Perelman School of Medicine Philadelphia PA
2. Department of Otorhinolaryngology-Head and Neck Surgery; Aurora Medical Group, Milwaukee; WI
3. Department of Neurosurgery, University of Pennsylvania; Perelman School of Medicine; Philadelphia PA
4. Department of Radiology; University of Pennsylvania; Perelman School of Medicine Philadelphia PA