1. Department of Neurological Sciences, University of Chile, Santiago, Chile
2. Department of Cerebrovascular and Skull Base Surgery, Institute of Neurosurgery Asenjo, Providencia, Chile
3. Department of Neurology, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
4. Department of Neurosurgery, Hospital Barros Luco Trudeau, Santiago, Chile
5. Department of Neurosurgery, Universidad Santiago de Chile, Santiago, Chile
6. Department of Neurosurgery, Hospital de Coyhaique, Coyhaique, Chile