NIHR Signal Optometrists are cautious, but may be as good as ophthalmologists at monitoring a common cause of blindness

Published on 30 August 2016

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.

Optometrists are cautious, but may be as good as ophthalmologists at monitoring a common cause of blindness

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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).

Bibliography

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.

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).

Bibliography

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.

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

Published on 8 July 2016

B Reeves, L Scott, J Taylor, S Harding, T Peto, A Muldrew, R Hogg, S Wordsworth, N Mills, D O'Reilly, C Rogers, U Chakravarthy

BMJ Open , 2016

Objectives To compare the ability of ophthalmologists versus optometrists to correctly classify retinal lesions due to neovascular age-related macular degeneration (nAMD). Design Randomised balanced incomplete block trial. Optometrists in the community and ophthalmologists in the Hospital Eye Service classified lesions from vignettes comprising clinical information, colour fundus photographs and optical coherence tomographic images. Participants' classifications were validated against experts' classifications (reference standard). Setting Internet-based application. Participants Ophthalmologists with experience in the age-related macular degeneration service; fully qualified optometrists not participating in nAMD shared care. Interventions The trial emulated a conventional trial comparing optometrists' and ophthalmologists' decision-making, but vignettes, not patients, were assessed. Therefore, there were no interventions and the trial was virtual. Participants received training before assessing vignettes. Main outcome measures Primary outcome—correct classification of the activity status of a lesion based on a vignette, compared with a reference standard. Secondary outcomes—potentially sight-threatening errors, judgements about specific lesion components and participants' confidence in their decisions. Results In total, 155 participants registered for the trial; 96 (48 in each group) completed all assessments and formed the analysis population. Optometrists and ophthalmologists achieved 1702/2016 (84.4%) and 1722/2016 (85.4%) correct classifications, respectively (OR 0.91, 95% CI 0.66 to 1.25; p=0.543). Optometrists' decision-making was non-inferior to ophthalmologists' with respect to the prespecified limit of 10% absolute difference (0.298 on the odds scale). Optometrists and ophthalmologists made similar numbers of sight-threatening errors (57/994 (5.7%) vs 62/994 (6.2%), OR 0.93, 95% CI 0.55 to 1.57; p=0.789). Ophthalmologists assessed lesion components as present less often than optometrists and were more confident about their classifications than optometrists. Conclusions Optometrists' ability to make nAMD retreatment decisions from vignettes is not inferior to ophthalmologists' ability. Shared care with optometrists monitoring quiescent nAMD lesions has the potential to reduce workload in hospitals.

Age-related macular degeneration (AMD) affects the macula, which is part of the retina at the back of the eye that is responsible for central vision. AMD is normally split into two types, “dry” and “wet”. Dry AMD is the more common type and it causes a gradual and progressive visual loss. About one in 10 people with AMD develop “wet” AMD. This is where fragile new blood vessels start to grow to supply the damaged retina. These can bleed easily and lead to scarring which can lead to rapid and permanent loss of vision.

Expert commentary

This virtual trial is useful because it shows with appropriate training; optometrists are just as good as ophthalmologists in detecting reactivation of AMD requiring new intervention and this could be shown without putting any patients at risk. This refutes any potential argument that optometrists lack the necessary skills and if anything they are more cautious than ophthalmologists.

The authors assert that a real world trial is not needed given the evidence provided here but not everyone will agree with this since what happens in the real world may not be the same as in this carefully constructed virtual model. There is sufficient information here to construct economic models of different options of care provision including patient's preferences and costs but how it all works in the real world will still need evaluation.

Mr Richard Wormald, Consultant Ophthalmologist; Co-ordinating Editor, Cochrane Eyes and VIsion