[1] Albert Ludwigs Univ Freiburg, Univ Med Ctr Freiburg, Med Fac, Dept Neurosurg, Freiburg, Germany
[2] Ruhr Univ Bochum, Univ Med Ctr Knappschaftskrankenhaus Bochum, Dept Neurosurg, Bochum, Germany
[3] Neuroloop GmbH, Freiburg, Germany
[4] Albert Ludwigs Univ Freiburg, Dept Microsyst Engn IMTEK, Lab Biomed Microtechnol, Freiburg, Germany
[5] Univ Freiburg, Fac Med, Med Ctr, Clin Trials Unit, Freiburg, Germany
[6] Univ Med Ctr Duesseldorf, Dept Prosthodont, Dusseldorf, Germany
[7] Albert Ludwigs Univ Freiburg, Univ Med Ctr Freiburg, Med Fac, Dept Stereotact & Funct Neurosurg, Freiburg, Germany
[8] Univ klinikum Freiburg, Freiburg, Germany