1. Corneal and External Eye Service, Bristol Eye Hospital, Bristol, United Kingdom;
2. School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London, London, United Kingdom;
3. Royal College of Ophthalmologists, London, United Kingdom;
4. Corneal and External Disease Service, Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom; and
5. International Centre for Eye Health, London School of Hygiene and Tropical Medicine, London, United Kingdom.