Teleophthalmology for preventable blindness screening in semi-urban primary care: a cost-effectiveness study from Brazil

Background Visual impairment from preventable causes remains a critical public health challenge in Brazil, where over 34% of the population has never undergone ophthalmic examination and specialist access is severely maldistributed. Diabetic retinopathy, glaucoma, age-related macular degeneration, and cataract are leading causes of preventable blindness, yet systematic screening in primary care remains rare in semi-urban municipalities. This study evaluated the cost-effectiveness of a teleophthalmology-based active screening pathway versus the standard Brazilian Unified Health System (SUS) passive referral pathway, assessed acceptability among professionals and patients, and estimated quality-adjusted life years (QALYs) gained through early detection. Methods A multicenter cross-sectional study was conducted across eight Primary Health Care Units in a semi-urban municipality in Rio de Janeiro state, Brazil (October 2025–March 2026). A total of 1,290 patients aged 50 years or older and/or with type 2 diabetes mellitus (T2DM) were screened using a portable non-mydriatic fundus camera with remote specialist reporting assisted by artificial intelligence (AI)-based segmentation. A two-arm decision tree compared intervention costs (bottom-up micro-costing) against standard pathway costs (SIGTAP 2024/SISREG 2024) from the public payer perspective. The primary effectiveness measure was time to diagnosis. A QALY scenario analysis was performed using Brazilian-validated utility coefficients. Acceptability was assessed using the System Usability Scale (SUScale; n = 13 professionals) and the Telehealth Usability Questionnaire – Brazil (TUQ-Brazil; n = 99 patients). Results Of 1,290 patients, 41.79% had abnormal findings and 2.32% had ungradable images. Mean time to diagnosis was 1.26 days versus 83 days via standard referral. Cost per detected case was R$50.64 versus R$70.82, a reduction of 28.5%. Teleophthalmology was absolutely dominant across all sensitivity scenarios. A QALY analysis (n = 376) yielded an incremental cost-effectiveness ratio (ICER) of –R$4,330/QALY, well below the SUS threshold (~ R$132,000/QALY). Professionals rated the platform 90.96 ± 5.91 (SUScale; “Excellent”). Patients reported a mean TUQ-Brazil score of 6.61 ± 0.32 out of 7.00, with 93.9% willing to reuse the service. Conclusions Teleophthalmology demonstrated absolute dominance over standard SUS referral in both cost-effectiveness and QALY analyses, delivering earlier diagnosis at lower cost. High bilateral acceptability supports scalability within the SUS, and these findings offer actionable evidence for policymakers considering portable fundus camera integration into semi-urban primary care networks.