Glaucoma goes unnoticed for years. The brain compensates — until it can't. Early detection depends on a single examination that today is done with an expensive, slow, and rarely available device. At the Institute of Advanced Studies we are working to change that.
Glaucoma goes unnoticed by the patient for years. The brain compensates for the loss — while it still can. Early detection depends on a single examination that today is done with an expensive, slow, and scarce device. At the Institute of Advanced Studies we are working to change that.
Institute of Advanced Studies · published April 2026
The silent loss of sight
Glaucoma is the second leading cause of irreversible blindness worldwide. The World Health Organization estimates that by 2040 more than 110 million people will be affected. Its insidious nature is in this: the patient does not notice it for years. Eye pressure rises slowly, the optic nerve gradually disappears, peripheral vision recedes step by step. Until one day the patient notices that the world looks like a tunnel — and the tunnel keeps narrowing.
The brain is remarkable in that it fills in missing data. If a defect appears in the visual field, the brain seals it — fills it with what the other eye sees, or constructs it from prior experience. Because of this, patients often realise the loss only when thirty or more percent of the visual field is gone forever. Glaucoma cannot be cured — we can only slow its further progression. That is why early detection is everything.
Perimetry — measuring the visual field
How does a doctor determine whether a patient really sees in every part of their visual field? They must test it point by point. This test is called perimetry. In practice it looks like this: the patient looks into a device shaped like a half dome, fixates on a central point, and presses a button whenever they detect a flash of light somewhere in the periphery. The test takes six to fifteen minutes per eye.
The classical clinical perimeter has been used for almost forty years. It is precise and standardised — but it has three fundamental weaknesses. First, it is expensive: one unit costs thirty to forty thousand euros. Many optometric and primary ophthalmology practices cannot afford it, so they refer patients to a separate examination at a hospital — weeks or often months later. Second, it requires a fixed position of the patient in a darkened room, is non-mobile — you cannot take it into the field, into a senior care facility or to a patient’s home. And third, it is exhausting: during a long test, fatigue makes patients invent answers towards the end.
The result? Perimetry — despite its key role — is the weakest link in glaucoma care. Audits in both Europe and the US show that fewer than forty percent of patients adhere to the recommended testing cadence (two tests a year for at-risk, four for affected). Many patients simply never come back after the first referral.
Enter virtual reality
At the Institute of Advanced Studies we are working to change this. Our answer is technologically elegant: perimetry built on commonly available virtual-reality headsets with integrated eye tracking. The principle remains the same — the patient observes light stimuli in the visual field and reacts to them. The way they do it, however, changes from the ground up.
A VR headset — goggles with two displays, one in front of each eye — creates a controlled, precisely calibrated visual environment. Eye tracking runs at 90 Hz. This means the system continuously checks whether the patient is maintaining fixation on the central point — and if not, automatically repeats the stimulus. No lost responses, no unreliable tests.
The second fundamental change is in the algorithm. Classical perimeters test each point relatively independently, which takes time. A modern Bayesian algorithm — built on open, scientifically validated methods — uses the fact that adjacent points in the visual field are interconnected. If one point is normal, we can predict the response in a neighbouring one with high probability. The test thus shortens to two and a half to four minutes per eye, while preserving the accuracy of the traditional standard.
“A test that today takes fifteen minutes in a darkened room can run in five minutes in the consulting room — and the result is in the medical record before the patient returns to the doctor.”
Benefits that count in years
Shortening the test is important, but not the most important. The real value of the platform is in continuity and accessibility.
Cost
A VR headset with clinical-grade eye tracking costs roughly an order of magnitude less than a traditional clinical perimeter. This opens the door for optometric clinics, small ophthalmology practices, geriatric facilities — all places where patients today do not get regular perimetry simply because the device is unavailable.
Standardised digital data
Results are stored in international formats (DICOM Visual Field Analyzer, HL7 FHIR), which means that when a patient changes doctors, their entire test history goes with them. Today, raw data is often lost on a change of practice — and with it the ability to compare tests over time, a key capability for detecting slow disease progression.
At-home monitoring
The patient can test at home — once or twice a week, conveniently, without travelling to the clinic. The clinician receives an aggregated report and an alert if something changes. Studies published in the past decade show that frequent at-home testing reveals disease progression twelve to eighteen months earlier than the standard schedule of two clinical visits per year. For a disease that cannot be reversed, those years are literally years of more sight.
Innovations that the traditional perimeter could never have
Virtual reality as a platform offers more than a better price. It opens space for entirely new diagnostic methods that traditional devices cannot provide.
Objective pupillometry
Our eyes do not respond to a light stimulus only consciously — the pupil contracts automatically. Eye tracking in the headset can capture this reaction with an accuracy classical perimeters cannot reach. This means we can also test patients who cannot cooperate: small children, patients with advanced dementia, post-stroke patients. For them, classical perimetry is today almost inaccessible.
A game instead of an exam, for children
A child patient does not sit still at a perimeter for fifteen minutes. In VR the test can be “butterfly hunt” or “catch the star” — the patient has fun, and the results are valid. Paediatric studies show an increase in successfully completed tests from forty to over eighty percent.
Linking structure and function
Another examination — optical coherence tomography — shows what the optic nerve looks like. The functional test (perimetry) shows what the patient actually sees. Our algorithm joins these two views. If the structural test shows nerve fibre loss but perimetry has not yet detected the corresponding defect, the system flags preperimetric glaucoma. These are patients we currently cannot detect until two or three more years pass and the damage deepens.
The science behind it
Our work is not an experiment. It rests on decades of research in Bayesian psychophysics — the discipline that studies how to efficiently measure perceptual thresholds using probabilistic models. It rests on the international open perimetry initiative, which gathers validated algorithms and normative databases. And it rests on a growing body of clinical studies comparing VR perimetry with traditional devices — which show that with proper design, VR achieves equivalent sensitivity to a tenfold more expensive classical instrument.
Our own methodological choices — selecting open algorithms over patented ones, focusing on patient outcomes rather than purely technical parameters, long-term availability without dependence on a single vendor — reflect the ethos of the Institute of Advanced Studies: independent science in the service of the public good.
The road ahead
The development of medical devices is not fast. Before full clinical availability we face prospective clinical studies, peer-reviewed publications in top ophthalmology journals, and regulatory certification in the European Union and the United States — a process that will take roughly another three to four years. The science, however, already speaks clearly: virtual reality is not a game; it is a tool of medicine.
And for millions of people who today are losing their sight because testing is unavailable, it can be the difference between diagnosis at forty and at sixty. That is the difference between twenty years of sight and a tunnel.
At the Institute of Advanced Studies we believe this future is worth bringing to it the very best that today’s science, technology and clinic can offer. Glaucoma does not wait. Perimetry, finally, no longer has to either.
Institute of Advanced Studies (IOAS) · Inštitút pokročilých štúdií, o. z. Gagarinova 3, 911 01 Trenčín, Slovakia director@ioas.pro · +421 903 667 654
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