1. Division of Neurosurgery, Clinics Hospital, School of Medicine, University of São Paulo, São Paulo, Brazil, and Barrow Neurological Institute, Phoenix, Arizona
2. Division of Neurosurgery, Clinics Hospital, School of Medicine, University of São Paulo, São Paulo, Brazil
3. Hospital Alemão Osvaldo Cruz, São Paulo, Brazil
4. Division of Pathology, Clinics Hospital, School of Medicine, University of São Paulo, São Paulo, Brazil