1. Radiologist and Researcher in Porto Alegre, RS, Brazil
2. Department of Morphological Sciences, Institute of Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
3. Department of Otolaryngology, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil
4. Department of Radiology, Hospital Ernesto Dornelles, Porto Alegre, RS, Brazil
5. Department of Neurosurgery, Centro Avançado de Neurologia e Neurocirurgia (CEANNE), Porto Alegre, RS, Brazil
6. Postgraduate Program in Medicine: Surgical Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
7. Division of Otolaryngology, Clínica Lavinsky, Porto Alegre, RS, Brazil