1 Ophthalmology and Visual Sciences, Division of Clinical Neurosciences, B Floor, EENT Centre, Queen's Medical Centre, University of Nottingham, Nottingham, UK.
2 Ophthalmology and Visual Sciences, Division of Clinical Neurosciences, B Floor, EENT Centre, Queen's Medical Centre, University of Nottingham, Nottingham, UK. harminder.dua@nottingham.ac.uk.