Fundus imaging is widely used for diagnosing and monitoring ocular diseases such as diabetic retinopathy, glaucoma, and age-related macular degeneration. However, the high cost and limited availability of conventional fundus cameras pose significant barriers, particularly in resource-constrained settings. This study introduces the Glaucoma Screening on Phone (GSoP), an affordable and portable smartphone-based fundus imaging adapter designed to address these challenges. The adapter was developed using accessible and cost-effective components. We recorded retinal videos from dilated pupil with a focus on the optic disc region, which provides critical information on the degeneration of the optic nerve. While clinical trials revealed artifacts such as glare and noise that reduced overall image quality, the GSoP demonstrated its ability to capture diagnostically relevant images of the optic disc region. A subjective qualitative comparison with the commercially available ophthalmoscope called oDocs-nun showed that although the GSoP’s field of view is smaller, it effectively highlights the optic nerve head, a critical area for glaucoma screening. Our approach is well-suited for mydriatic video-based screening due to its limited field of view. With a production cost of under C10, the GSoP offers a practical and accessible solution for primary healthcare and educational purposes. Future improvements, including glare reduction mechanisms, AI-driven automation, and modular design options, have the potential to enhance its diagnostic capabilities and broaden its impact.

The authors have declared no competing interest.

This study was funded by the 5E - Group T Fund, KU Leuven, under grant No. ZKD7969-00-W01

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Institutional Review Board of Institute of Health of Jimma University gave ethical approval for this work.

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* This work was granted by the 5E - Group T Fund, KU Leuven, under grant No. ZKD7969-00-W01

solomongebru.abaykuleuven.be; melkamuhunegnaw.asmarekuleuven.be; lucca.geurtskuleuven.be

All data produced in the present study are available upon reasonable request to the authors