[1] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Surg, Div Neurosurg, BR-05508 Sao Paulo, Brazil
[2] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Anat, Div Neurosurg, BR-05508 Sao Paulo, Brazil
[3] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Anat, Div Anat, BR-05508 Sao Paulo, Brazil
[4] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Surg, Div Anat, BR-05508 Sao Paulo, Brazil
[5] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Pathol, BR-05508 Sao Paulo, Brazil
[6] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Neurol Psychiat & Med Psychol, BR-05508 Sao Paulo, Brazil
[7] Univ Fed Rio de Janeiro, Dept Pathol, Rio De Janeiro, Brazil