1. Department of Neurosurgery, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland
2. Clinical Neuroscience Center, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland
3. Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, UMC Utrecht, 3584 CX Utrecht, The Netherlands
4. Department of Neurosurgery, Careggi Hospital and University of Florence, 50134 Florence, Italy
5. Department of Neurology, University Hospital Zurich, University of Zurich, 8091 Zurich, Switzerland