[1] National Hospital for Neurology & Neurosurgery,Acute Stroke and Brain Injury Service
[2] National Hospital for Neurology & Neurosurgery,Lysholm Department of Neuroradiology
[3] National Hospital for Neurology & Neurosurgery,Victor Horsley Department of Neurosurgery
[4] University College London and Royal Free,Clinical Research Fellow, The Hatter Cardiovascular Institute, Division of Medicine
[5] Hospital Medical School,undefined