Smartphones could be used to screen for cataracts and other eye problems

London, UK: Researchers have found a high level of agreement between cataract referral decisions based on smartphone images reviewed remotely and those made by ophthalmologists examining patients in person at rural eye camps.

The finding could make it possible for health workers to detect cataracts, pterygia (a fleshy growth on the white of the eye) and other eye diseases in people who live in remote rural areas and who find it difficult to visit an ophthalmologist, either because of geographical barriers or because of age or infirmity.

Dr Prabhu Krishna Ravilla, a medical officer at Aravind Eye Hospital, Madurai, India, told the 44^th Congress of the European Society of Cataract and Refractive Surgeons (ESCRS) today (Sunday) that the results of the study could play an important role in tackling cataracts and preventing blindness in the future [1].

“Cataract is still the major cause of global blindness, affecting nearly 100 million people worldwide, and it disproportionately impacts low-resource settings where access to eye specialists is severely limited,” he said.

“In India and similar countries, the primary model for reaching rural communities has long been the ‘eye camp’ – temporary outreach clinics where ophthalmologists travel from urban hospitals to rural sites on fixed dates. But this model has serious constraints: it's expensive, logistically complex, entirely dependent on specialist availability and reaches only a fraction of those who need it.

“An earlier Aravind Eye Hospital study found that eye camps screened only 7% of rural residents in the targeted region, with attendance dropping by 80% for those living more than three kilometres away – and among those who didn't attend, one-third needed cataract surgery. Women, the elderly and the poorest communities are most underserved. The COVID-19 pandemic made things worse by halting outreach activities entirely.”

Dr Ravilla and his colleagues developed a small, portable attachment that clips on to an Android phone. It contains a lens to magnify the front of the eye, two small white LEDs powered by the phone and a silicone scope that rests comfortably against the patient's eye socket, blocking ambient light and maintaining a fixed, consistent distance from the eye. The device is made in India and is inexpensive, costing less than £150, including the phone [see attached images]. It is paired with a mobile app that is used for telemedicine in areas with low bandwidth, and is available in English and Tamil.

“We hypothesised that a low-cost, easy-to-use smartphone imaging device could allow community health workers – people with minimal ophthalmic training – to capture diagnostic-quality eye images in the field, which could then be reviewed remotely by ophthalmologists. This would decouple the need for a specialist to be physically present at every screening,” he said.

After three hours’ training, the community health workers (CHWs) screened 1093 patients in 19 rural eye camps at five towns near the city of Pondicherry in Tamilnadu (Chengam, Tiruvannamalai, Cheyyar, Arani and Cuddalore) targeting rural villages around these towns. Diagnoses and referral decisions were made by remote ophthalmologists and then compared with those by ophthalmologists who saw the patients in person at the same eye camps.

“The most clinically important finding was that when the remote ophthalmologist reviewed the smartphone images and the in-person eye camp doctor independently decided whether a patient needed to be referred to hospital for further care, they agreed in 96 out of every 100 cases,” said Dr Ravilla.

There was substantial agreement between the two doctors on the diagnosis of any cataract – they agreed in 89% of cases – mature cataracts (96%), immature cataracts (85%), no cataract, described as clear crystalline lens (89%), and pseudophakia (identifying eyes that already had a lens implant) (97%). There was moderate agreement on pterygia (94%). The CHWs learned quickly to screen each eye in less than 2.5 minutes, and agreement between doctors increased with the quality of the images.

“These findings challenge the assumption that specialist presence is necessary for accurate cataract screening. They suggest a model where a trained ophthalmologist's time is used for diagnosis and decision-making – where it is most valuable – rather than travel and in-person examination,” said Dr Ravilla. “For patients, particularly in rural and underserved communities, door-to-door screening becomes imaginable.

“For policymakers and public health planners, it offers a potential path to scaling up cataract screening without a proportional increase in a specialist workforce. The platform integrates with existing community health worker infrastructure, works in low-bandwidth environments, and has demonstrated patient acceptability. It is also compatible with future AI-based grading, which could eventually reduce dependence on remote ophthalmologist review for initial triage.”

The researchers plan further investigations, including adding slit-beam and blue light or dilated-eye images to improve diagnostic accuracy; these are included in the comprehensive eye examination that is considered the gold standard for detecting cataracts and other eye problems. They also plan to explore AI-assisted cataract grading, and to assess the platform's effectiveness and generalisability in other geographic and cultural settings beyond rural South India.

At present, the results may not be generalisable to other settings, and further research is required to see if the technology could be more widely applicable and deployed across the globe in areas with reduced access to eyecare, including the Americas, Asia, Africa, rural parts of Europe etc.

The study does not compare remote assessment by eye camp doctors who used penlights with the gold standard in which an ophthalmologist is ‘masked’ to prevent any bias and uses the more accurate slit lamp; therefore, limited conclusions can be drawn from it. Other limitations include the platform performed less well for non-lens diagnoses such as pterygium, refractive error and corneal opacity; and the eye camp doctors sometimes examined eyes after pupil dilation whereas the CHWs captured images before dilation, which may have limited the remote ophthalmologists’ ability to grade cataract severity.

Strengths of the study include its large, real-world sample, CHWs had minimal training, which makes the results more generalisable, and the technology was designed with the local environment, manufacturing capacity and affordability in mind. It was a collaboration between Johns Hopkins University in the US and Aravind Eye Care System.

ESCRS President, Professor Burkhard Dick, chair of the ophthalmology department at the University Eye Hospital Bochum, Germany, who was not involved in the research, said: “This is a promising approach for under-served regions, where access to ophthalmologists can be limited, and is an example of how the ESCRS encourages research that investigates the feasibility of reaching patients who find it difficult to consult an ophthalmologist in conventional clinics.

“The high level of agreement on referral decisions is encouraging. It should not be regarded as a replacement for a comprehensive ophthalmological examination, particularly as the in-person comparison in this study was based on assessments conducted in rural eye camps and performance was weaker for some non-lens conditions. However, as a carefully governed screening and triage tool, it could enable ophthalmologists to use their expertise remotely and help more people access timely cataract assessment and treatment. Further research in other settings will now be important to establish how widely the approach could be applied.”

(ends)

Notes to editors:

Please acknowledge the ESCRS Congress as a source in any articles.

[1] Abstract FP08.01, ‘Decentralizing cataract screening: validation of a novel smartphone-based anterior segment imaging system for remote diagnosis of anterior segment eye disease’, by Prabhu Krishna Ravilla et al, ‘Frontiers in anterior segment imaging and diagnostics’ session, 14.00-15.30 hrs BST, Sunday 13 September: https://pagv3.virtual-meeting.org/escrs/escrs2026/en-GB/pag/presentation/575014?guestPreview=1&q=FP08.01&view=list&segment=presentations&sort=starts_at 

[2]

Funding: The study was funded by the following: National Eye Institute grants R21EY034343, K23EY032988, and P30EY01765 (Biostatistics Core); a Microsoft Innovation Acceleration Award; the Johns Hopkins Center for Global Health; the Stephen F. Raab and Mariellen Brickley-Raab Rising Professorship in Ophthalmology; and the T. Boone Pickens Rising Professorship in Ophthalmology.

Note: When obtaining outside comment, journalists are requested to ensure that their contacts are aware of the embargo on this release.

The European Society of Cataract and Refractive Surgeons (ESCRS) was founded in 1991 to promote education and research in the field of implant and refractive surgery and to advance and promote the study and practice of ophthalmology. It has over 7,500 members from 130 countries worldwide. https://www.escrs.org/

The ESCRS Congress is the once-a-year occasion when about 16,000 ophthalmology experts from 120 countries come together to present and discuss their latest discoveries for improving and preserving eyesight. https://congress.escrs.org/ #ESCRS2026