1Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, United Kingdom, 2Translational Imaging Group, UCL, London, United Kingdom, 3Developmental Imaging and Biophysics Section, UCL Institute of Child Health, London, United Kingdom, 4Centre for Medical Imaging, UCL, London, United Kingdom, 5Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, London, United Kingdom