[1] Univ Utrecht, Med Ctr, Dept Neurol, NL-3484 CX Utrecht, Netherlands
[2] Univ Utrecht, Med Ctr, Dept Neurosurg, Rudolf Magnus Inst Neurosci, NL-3484 CX Utrecht, Netherlands
[3] Univ Amsterdam, Acad Med Ctr, Dept Neurosurg, NL-1105 AZ Amsterdam, Netherlands
[4] Vrije Univ Amsterdam, Med Ctr, Dept Neurosurg, NL-1081 HV Amsterdam, Netherlands