*Department of Ophthalmology, Moorfields Eye Hospital, London, United Kingdom; and

†Tennent Institute of Ophthalmology, Gartnavel Hospital, Glasgow, United Kingdom.

Reprint requests: Edward J. Casswell, MBBS, Moorfields Eye Hospital, 162 City Road, London EC2A 4PD, United Kingdom; e-mail: [email protected]

E. J. Casswell was supported by the Royal College of Surgeons in Edinburgh (RCSEd). The funding organization had no role in the design or conduct of this research. The views expressed in this publication are those of the author(s) and not necessarily those of the RCSEd. D. G. Charteris is supported by the National Institute for Health Research (NIHR) Biomedical Research Centre based at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology. The funding organization had no role in the design or conduct of this research. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health.

None of the authors has any financial/conflicting interests to disclose.