We thank K. Kavukcuoglu, A. Zisserman, M. Jaderberg, K. Simonyan for discussions, A. Cain and M. Cant for work on the visuals, D. Mitchell and M. Johnson for infrastructure and systems administration, J. Morgan and OpenEyes for providing the electronic health record records, T. Peto, P. Blows, A. O’Shea and the NIHR Clinical Research Facility for work on the labeling, T. Heeran, M. Lukic, K. Kortum, K. Fasler, S. Wagner and N. Pontikos for work on the labeling, E. Steele, V. Louw, S. Gill and the rest of Moorfields IT team for work on the data collection and deidentification, S. Al-Abed and N. Smith for Moorfields technical advice at project initiation, R. Wood and D. Corder at Softwire for engineering support at Moorfields, R. Ogbe and the Moorfields Information Governance team for support, M. Hassard for Moorfields research and development support, K. Bonstein and the National Institute for Health Research (NIHR) for support at the Moorfields Biomedical Research Centre (BRC), J. Besley for legal assistance, E. Manna for patient engagement and support, and the rest of the DeepMind team for their support, ideas and encouragement. P.A.K. is supported by an NIHR Clinician Scientist Award (NIHR-CS-2014-14-023). D.A.S., A.T., C.E. and P.T.K. are supported by the NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology and the NIHR Moorfields Clinical Research Facility. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health. R.C. receives studentship support from the College of Optometrists, United Kingdom.