What can modern eye tracking do for ophthalmic testing?
Author(s): Nadia Paraskevoudi, Marc Tonsen, Miguel Garcia, Neil M. Thomas, Kai Dierkes
August 7, 2023
Glaucoma: The silent thief of sight and its societal impacts
Glaucoma is an eye condition that causes progressive deterioration of the optic nerve, the nerve connecting the eye to the brain, leading to blind spots in vision. Approximately 10-13% of people in Europe are affected by glaucoma (Rossetti et al., 2015), with the cost per patient varying between €11-19K per year depending on the stage of the disease (Bo Poulsen et al., 2005; Traverso et al., 2005).
Often dubbed the "silent thief of sight," glaucoma is painless and typically only noticed when irreversible vision loss has occurred. Consequently, early detection is important to reduce its impact, especially given the significant societal challenges and its detrimental effects on patients' quality of life.
Pupil Labs and Reyedar are now collaborating to integrate eye tracking and artificial intelligence (AI) technologies, aiming to improve early glaucoma detection methods.
Limitations and challenges of traditional Glaucoma detection
Typically, glaucoma is diagnosed by eye doctors at ophthalmological units once suspicion of the condition arises. The diagnostic process may involve tonometry, a technique measuring pressure in the eye, and retinography to capture an image of the eye’s fundus. Subsequently, campimetry or perimetry is performed to identify visual field defects, a process known as functional testing. Functional testing requires the patient to actively engage and subjectively report their visual perception, with a qualified clinician interpreting the results for diagnosis.
Despite being the current gold standard for glaucoma detection, this process is time-consuming and tedious for patients. Furthermore, it necessitates a medical professional to conduct and interpret the test, limiting its accessibility and potentially leading to late diagnosis, often when the disease has advanced and symptoms have become noticeable. Therefore, there is a pressing need for easy-to-perform functional tests that can be conducted outside of the clinical environment and administered by practitioners without specialised skills. Such tests could facilitate better prevention as they allow for earlier screening and detection by less specialised personnel who can then refer the patient for diagnosis.
Eye tracking: A disrupter in early Glaucoma detection?
Eye tracking is a technique widely employed in the field of vision sciences that objectively characterises gaze behaviour in response to visual stimuli. However, it has traditionally been challenging to utilise, requiring specialist knowledge and/or operator training. Neon has recently made eye tracking more accessible and robust, effectively democratising what was once a specialist tool to lay users. This was a key motivation for incorporating Neon into Reyedar’s glaucoma detection approach, as it can be used to quickly and objectively evaluate eye movement characteristics.
Figure 1: Neon eye tracking glasses with exchangeable prescription lenses. Custom frame design for Reyedar.
Reyedar's method, which uses Neon to track the eyes, offers a user-friendly and viable alternative to traditional functional testing. During a three-minute testing session, the method gathers hundreds of thousands of data points by presenting standardized stimuli to the patient. These stimuli are designed to provoke specific eye movement responses and examine different areas of the visual field. AI-based mathematical techniques are then used to generate a biomarker that provides clinicians with important insights for detecting Glaucoma. Reyedar's testing can be performed by non-glaucoma specialists and does not require calibration, making it particularly beneficial for quicker screening applications, and where a specialist may not be available to operate the eye tracking component of the setup.
Transforming eye care and patient experiences
We are pleased to see that eye tracking has reached a stage where its ease of use and robustness make it a viable tool for ophthalmic testing, offering tangible promise to improve the quality of life for people with glaucoma via early screening and detection. For future developments in the field, we encourage you to follow Reyedar's updates on their website and LinkedIn.
Rossetti, L., et al. (2015) Blindness and Glaucoma: A Multicenter Data Review from 7 Academic Eye Clinics. PLoS ONE 10(8): e0136632. https://doi.org/10.1371/journal.pone.0136632
Poulsen, P. B., Buchholz, P., Walt, J. G., Christensen, T. L., & Thygesen, J. (2005). Cost analysis of glaucoma-related-blindness in Europe. International Congress Series, 1282, 262–266. https://doi.org/10.1016/j.ics.2005.05.091
Traverso, C. E., et al. (2005). Direct costs of glaucoma and severity of the disease: A multinational long term study of resource utilisation in Europe. British Journal of Ophthalmology, 89(10), 1245–1249. https://doi.org/10.1136/bjo.2005.067355