1. Department of de Neurosurgery, Federal University of Rio de Janeiro, University Hospital Clementino Fraga Filho,
Rio de Janeiro RJ, Brazil
2. Department of de Neurosurgery, State University of Rio de Janeiro, University Hospital
Pedro Ernesto, Rio de Janeiro RJ, Brazil
3. Department of Neurosurgery, Santa Casa de Belo Horizonte, Rio de Janeiro
RJ, Brazil