[1] Uppsala Univ, Uppsala Univ Hosp, Neurosurg, Dept Neurosci, Uppsala, Sweden
[2] Lund Univ, Skane Univ Hosp, Dept Clin Sci Lund, Neurosurg, Lund, Sweden
[3] Karolinska Inst, Dept Neurosci, Solna, Sweden
[4] Karolinska Inst, Karolinska Univ Hosp, Dept Med & Clin Neurosci, Neurosurg, Stockholm, Sweden
[5] Univ Gothenburg, Sahlgrenska Acad, Sahlgrenska Univ Hosp, Dept Clin Neurosci,Neurosurg, Gothenburg, Sweden
[6] Linkoping Univ, Linkoping Univ Hosp, Neurosurg, Dept Clin & Expt Med, Linkoping, Sweden
[7] Umea Univ, Umea Univ Hosp, Dept Clin Neurosci, Neurosurg, Umea, Sweden
[8] Copenhagen Univ Hosp, Rigshosp, Dept Neurosurg, Copenhagen, Denmark