1 Neurosurgery Service and Gamma Knife Center, Lausanne University Hospital (CHUV), Lausanne, Switzerland.
2 Assistance Publique-Hôpitaux de Paris, Hôpitaux Universitaires Paris Sud, Centre Hospitalier Universitaire de Bicêtre, Service de Neurochirurgie, Le Kremlin-Bicêtre, France.
3 Université de Lausanne (Unil), Faculté de Biologie et de Médecine (FBM), Lausanne, Switzerland.
4 Signal Processing Laboratory (LTS 5), Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland.