1. Division of Anaesthesia, Addenbrooke's Hospital, University of Cambridge, Cambridge, United Kingdom.
2. Department of Surgery, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
3. Clinician Investigator Program, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
4. Section of Brain Physics, Division of Neurosurgery, Addenbrooke's Hospital, University of Cambridge, Cambridge, United Kingdom.
5. Department of Neurosurgery, Cantonal Hospital Chur, Basel, Switzerland.
6. Department of Anesthesiology, Baylor College of medicine, Houston, Texas.