Optometrists seem to be as good as ophthalmologists at correctly classifying wet age-related macular degeneration (AMD).
Wet AMD is a condition where new blood vessels develop at the back of the eye to supply the damaged macula, responsible for central vision. It can cause permanent vision loss if not treated quickly. Monthly follow-up in specialist clinics is then required to check the condition hasn’t reactivated, which places a high demand on resources.
This virtual trial using computer images and clinical information compared decision-making between optometrists and ophthalmologists to see if there is scope for shared community care to take the pressure off the UK Hospital Eye Service. The findings suggest there is potential for this, though cost-effectiveness needs to be assessed. Optometrists would need specialised training and the correct equipment, although many practices are reported to have already invested in this equipment.
Why was this study needed?
Age-related macular degeneration affects more than 600,000 people in the UK and is the leading cause of vision loss. About 10-15% of these people have the wet form of AMD, which untreated can cause vision to deteriorate within days. Treatment involves injection of drugs into the eye to stop the blood vessel growth. However, because the condition can ‘reactivate’, people with wet AMD require regular monthly reviews in the UK Hospital Eye Service to determine if treatment needs to recommence. Monitoring can be a burden for patients and carers, and places a high demand on healthcare resources. UK hospitals can struggle to provide appointments at regular intervals. This has prompted a review of how the service is provided.
Shared care between community optometrists and the hospitals for eye conditions other than wet AMD is well established. The trial aimed to determine if optometrists are as good as ophthalmologists for assessing the status of wet AMD at follow up clinics.
What did this study do?
This NIHR funded randomised controlled trial (ECHoES) included 48 UK ophthalmologists with experience of the AMD service and 48 qualified UK optometrists with at least three years training post registration but no AMD experience.
It was a virtual trial that did not involve examining actual patients but where participants were asked to review retinal images (optical coherence tomograms) and accompanying clinical information mimicking real patients, herein referred to as ‘scenarios’. Participants were asked to assess the status of AMD – whether it had reactivated, looked suspicious or was dormant – and this was compared against the judgment of three separate experts.
The main outcome of interest was correct classification of the status of wet AMD. Other outcomes were potentially sight-threatening errors, judgements about specific components of the condition, and the participant’s self-rated confidence in decision-making.
What did it find?
- There was no significant difference in the ability to correctly classify scenarios between optometrists (84.4%; 1,702 of 2,016) compared with ophthalmologists (85.4%; 1,722 of 2,016; odds ratio [OR] 0.91, 95% confidence interval [CI] 0.66 to 1.25).
- The number of potentially sight-threatening errors was also no different between optometrists and ophthalmologists (5.7% vs. 6.2%; OR 0.93, 95% CI 0.55 to 1.57).
- Looking at specific components, optometrists were more likely than ophthalmologists to correctly classify reactivated wet AMD (80.0% vs. 74.0%), but were less likely to correctly classify scenarios as dormant or suspicious (88.7% vs. 96.5%).
- However, ophthalmologists were more confident in their classifications. Ophthalmologists were ‘very confident’ for 58.3% of scenarios (1,175 of 2,016) compared to optometrists having the same level of confidence for only 28.5% of scenarios (575 of 2,016).
What does current guidance say on this issue?
Joint commissioning guidance on AMD states that people with wet AMD need monthly monitoring appointments for between three months to two or more years. They describe that the biggest challenge for AMD services is to ensure patients receive these follow-up appointments on time so as to minimise preventable sight loss. Innovative service models to improve initial detection and referral times from community to specialist clinics are described, which all had well integrated IT systems. However, there is no guidance about the role of community optometrists for providing follow-up care.
What are the implications?
This scenario-based study provides evidence that community optometrists are as good as ophthalmologists at correctly classifying lesions, although they made more cautious decisions. This can be desirable in minimising false negatives and aligns with community optometrist’s obligations to refer anything suspicious. However, if service change to the community was associated with large numbers of non-threatening conditions being referred back to UK Hospital Eye Services this could limit the potential for shared care to reduce the workload.
Cost and cost-effectiveness needs to be assessed, which should include the provision of specialised training and equipment for optometrists.
A limitation to this study is that virtual decision-making may not reflect real-life in person decision making, where history taking and examination are included skills.
Citation and Funding
Reeves B, Scott L, Taylor J, et al. Effectiveness of Community versus Hospital Eye Service follow-up for patients with neovascular age-related macular degeneration with quiescent disease (ECHoES): a virtual non-inferiority trial. BMJ Open. 2016;6(7):e010685.
This project was funded by the National Institute for Health Research Health Technology Assessment Programme (project number 11/129/195).
NHS Choices. Macular degeneration. London: Department of Health; 2015.
The College of Optometrists and The Royal College of Ophthalmologists. Commissioning better eye care: age-related macular degeneration. London: The College of Optometrists and The Royal College of Ophthalmologists; 2013.
Produced by the University of Southampton and Bazian on behalf of NIHR through the NIHR Dissemination Centre