1. Department of Anaesthesiology University Hospitals Leuven KU Leuven 3000 Leuven Belgium
2. Maastricht MultiModal Molecular Imaging (M4I) institute Division of Imaging Mass Spectrometry Maastricht University Maastricht The Netherlands
3. Neurosurgery Department University Hospitals Leuven Laboratory for Experimental Neurosurgery and Neuroanatomy Department of Neurosciences KU Leuven 3000 Leuven Belgium
4. Department of Anaesthesiology University Medical Center Groningen University of Groningen The Netherlands
5. Toxicology and Pharmacology Department KU Leuven 3000 Leuven Belgium