1. Institute of Neurology and Neurosurgery of Passo Fundo, Passo Fundo, RS, Brazil
2. Associação Hospitalar São Vicente de Paulo (HSVP), Passo Fundo, RS, Brazil
3. Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
4. Department of Pathology, Santa Casa de Misericórdia de Porto Alegre, Porto Alegre, RS, Brazil
5. School of Medicine, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
6. Researcher of School of Medicine of ABC, Santo André, São Paulo, Brazil
7. Pontifícia Universidade Católica de São Paulo, São Paulo, Brazil
8. Department of Neurosurgery, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil