[1] Imperial Coll London, Med Sch, London, England
[2] Univ Hosp Birmingham NHS Fdn Trust, Birmingham, England
[3] Univ Birmingham, Birmingham, England
[4] Univ Birmingham, Inst Metab & Syst Res, Translat Brain Sci, Edgbaston, England
[5] Ctr Endocrinol Diabet & Metab, Birmingham, England
[6] Univ Hosp Birmingham NHS Fdn Trust, Dept Neurol, Birmingham, England
[7] Univ Hosp Birmingham NHS Fdn Trust, Birmingham Neuroophthalmol, Birmingham B15 2GW, England