1. MRC Biochemical and Clinical Magnetic Resonance Unit, Department of Biochemistry, University of Oxford, and Department of Neurosurgery, Oxford Radcliffe Hospitals, Oxford, United Kingdom.
2. MRC Biochemical and Clinical Magnetic Resonance Unit, Department of Biochemistry, University of Oxford, and Department of Neurology, Oxford Radcliffe Hospitals, Oxford, United Kingdom.
3. MRC Biochemical and Clinical Magnetic Resonance Unit, Department of Biochemistry, University of Oxford, Oxford, United Kingdom.
4. Department of Anaesthetics, Oxford Radcliffe Hospitals, Oxford, United Kingdom.