Online visual field testing (perimetry) has many advantages over conventional machine-based perimetry. These include:
A more enjoyable experience for test-takers
As a busy Ophthalmologist and glaucoma specialist in Melbourne, every day I see dozens of patients who perform visual field testing. Using the conventional machine-based perimeters I was struck by how strongly they disliked the experience of visual field testing. This puzzled me greatly – what was it about visual field testing that was so unpleasant? Could we design a different way of doing it, which would not be so unpleasant, but would provide the same information? It was these thoughts that caused me to build an online visual field test, and create the Australian health tech company Eyeonic.
There are so many ways we can design an online app; hence so many options to make online perimetry more user-friendly.
There are several features that make the online Eyeonic visual field test more enjoyable than machine-based perimetry. Our test targets and fixation star are friendly to see, and encouraging sounds and helpful commentary guide the user through the test. A progress bar is present throughout the test, letting the user know how much longer there is to go. The test senses the user’s reflex time, and slows down or speeds up accordingly, so the user does not feel rushed or slowed down – the test goes at the right tempo for them. Because the computer’s webcam is monitoring the user throughout the test, they do not need to put their head in a brace, near an unsterilised bowl; the experience is much more familiar to them like regular computer use.
Figure 1. Spinning star fixation target, with blue-on-grey progress bar underneath. The length of the blue portion lets you know how far you have progressed during the test
These features explain why people so strongly prefer the online Eyeonic visual field test to machine-based visual field testing. In a survey of 95 test takers, 84% preferred the Eyeonic online test to machine perimetry; only 2% preferred the machine while the remaining 14% preferred neither. A 10-item survey was asked about various aspects of the experience of visual field testing, and a preference to online over machine perimetry was reported in 10/10 items; 8 of these reached statistical significance. This is a strong endorsement confirming the improved user experience of our test.
The ability for testing at home: telehealth
As online visual field testing will work on any computer, it can be performed by anyone at home. This has many benefits. If someone is too unwell or immobile to attend a clinic, or simply does not have the time or money to attend, they can still perform a test online. If people need more frequent visual field tests than visits with their eye healthcare professional, they may be able to avoid a visit to the clinic. Some people (eg those with high risk glaucoma) might benefit from monthly visual field testing, which is clearly not practical if they only see their clinician once or twice per year. Decoupling the field test from the clinic visit has these and other tremendous advantages. Even as we emerge from the Covid-19 pandemic, telehealth remains an important aspect of clinical care with many benefits for clinicians and patients.
Better Clinic Flow
Conventional, machine-based visual field testing slows down clinic flow. It can double the amount of time a person needs to spend at an eyecare practice – and exacerbate the well-known problem of waiting for doctors!
From the clinician’s perspective, the extra time their patients spend means more chair space needed in the waiting room, and more work for administrative staff and clinical assistants. If patients can arrive with their visual field test already done at home, it means less time and less inconvenience for all.
Cost Saving
An online test for glaucoma represents a significant cost saving for patients. Aside from the inconvenience of having to attend an eyecare practice every time they need a visual field test, providing the service remotely will be a major cost saving. This is especially true in parts of the world where access to visual field machines are scarce, and these machines can be extremely expensive relative to the average cost of eye healthcare. Decoupling visual field testing from dedicated machines can significantly reduce this financial barrier.
As well as cost saving for patients, clinicians also benefit financially. Dedicated visual field machines are expensive to purchase; for eye healthcare clinicians this is a significant investment which they can only hope to recover by on charging the cost of visual field tests to their patients. Large, bulky machines are often one-off purchases; in comparison a small ongoing monthly subscription fee is needed for unlimited access to online visual field testing.
Government or private healthcare funders will also save significantly. They will not have to purchase large machines that depreciate over time, require regular maintenance and eventual replacement. In comparison, an online service continually self-updates and improves, with the only hardware required are computers which have many other important uses in healthcare service delivery.
Better Continuity of Data and Data Control by Patients
When bulky machines are needed to perform visual field testing, the data is stored on those machines. This means your visual field data is owned by that clinic. If you move between clinics, it is not easy to extract that data from those machines, and harder still to import it into the machines at your new practice. Data being stored in machines reduces your options as a healthcare consumer. This is especially troubling if you have long-term glaucoma with years of follow up data; if you need to move to a new clinic that data is rendered virtually useless and your progress analysis needs to start again. Progress analysis is comparing sequential visual field tests for change over time. It is the heart of ongoing glaucoma monitoring and if disrupted can be quite negatively impactful for your eye care.
In comparison, when the visual field testing is online, the data is stored online. Your data is controlled by you – you chose who can see it, by selecting trusted clinicians. If you need to move to a different clinic, it is simply a matter of deselecting the old clinician and selecting the new one; the integrity of the sequential data for progress analysis is preserved. This model works very well for collaborative care between Optometry and Ophthalmology, where visual field testing at different practices can be added to the same database. This data is stored securely to the highest standards of data protection, under the vigilance of experts from Microsoft.
Improved access to sight saving healthcare for all
Perhaps most importantly, online visual field testing delivers increased access to all for sight saving technology. As an Ophthalmologist and glaucoma specialist based in some of the more privileged suburbs in Melbourne, I am conscious that many of my patients are the fortunate ones who can access our sight-saving services. We take for granted that in Melbourne and other Australian cities we are blessed with plentiful eye clinics; this is not the case for remote and regional parts of Australia, and many parts of the developing world. In Africa, and parts of Asia, where glaucoma is most prevalent, many people cannot afford or simply cannot access conventional visual field machines, and consequently their glaucoma is not as well managed.
Dedicated visual field machines are specialised, complex and expensive, depending on a trained workforce of clinical assistants and machinery operators. This is why they are scarce in many parts of the world where the need for better glaucoma care is greatest. Computers, in comparison, are versatile and everywhere – they are common throughout the developing world. Building online applications that work on commonplace hardware is much more sensible than having to supply speciality-crafted, expensive hardware with a very narrow range of use.
Online visual field testing means more people can access perimetry; barriers to healthcare access are lifted.
Perhaps most importantly, online visual field testing delivers increased access to all for sight saving technology.