[1] Univ Hosp Southampton, Dept Neurosurg, Southampton, England
[2] Kings Coll Hosp London, Dept Neurosurg, London, England
[3] Beaumont Hosp, Dept Neurosurg, Dublin, Ireland
[4] Leeds Teaching Hosp, Dept Neurosurg, Leeds, England
[5] Univ Hosp Sussex, Dept Neurosurg, Brighton, England
[6] North Bristol NHS Trust, Bristol Inst Clin Neurosci, Dept Neurosurg, Bristol, England
[7] Univ Coll London Hosp, Dept Neurosurg, London, England
[8] Cambridge Univ Hosp, Dept Neurosurg, Cambridge, England
[9] Barts Hlth NHS Trust, Dept Neurosurg, London, England
[10] Havering & Redbridge Univ Hosp, Dept Neurosurg, Romford, England
[11] Salford Royal Hosp, Manchester Ctr Clin Neurosci, Dept Neurosurg, Manchester, England
[12] Cardiff & Vale Univ Hlth Board, Dept Neurosurg, Cardiff, Wales
[13] Univ Hosp Southampton, Wessex Neurol Ctr, Tremona Rd, Southampton SO16 6YD, England