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Deep learning prediction of steep and flat corneal curvature using fundus photography in post-COVID telemedicine era

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Abstract

Recently, fundus photography (FP) is being increasingly used. Corneal curvature is an essential factor in refractive errors and is associated with several pathological corneal conditions. As FP-based examination systems have already been widely distributed, it would be helpful for telemedicine to extract information such as corneal curvature using FP. This study aims to develop a deep learning model based on FP for corneal curvature prediction by categorizing corneas into steep, regular, and flat groups. The EfficientNetB0 architecture with transfer learning was used to learn FP patterns to predict flat, regular, and steep corneas. In validation, the model achieved a multiclass accuracy of 0.727, a Matthews correlation coefficient of 0.519, and an unweighted Cohen’s κ of 0.590. The areas under the receiver operating characteristic curves for binary prediction of flat and steep corneas were 0.863 and 0.848, respectively. The optic nerve and its peripheral areas were the main focus of the model. The developed algorithm shows that FP can potentially be used as an imaging modality to estimate corneal curvature in the post-COVID-19 era, whereby patients may benefit from the detection of abnormal corneal curvatures using FP in the telemedicine setting.

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Data availability

Sample FP images of corneal curvature groups were deposited into a public repository (https://data.mendeley.com/datasets/bc2jfr7dv9) to validate the study. Data will be made available by the corresponding author upon reasonable request.

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Acknowledgements

Bo Young Lee and Hee Jin Kim played significant roles in preprocessing the data.

Funding

This research was supported by the “Regional Innovation Strategy (RIS)” through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (MOE) in 2023 (2022RIS-005) and by a National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (RS-2023–00251484).

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Contributions

TKY and JYC had full access to all the data in the study and take responsibility for the integrity of the data and accuracy of the data analysis. Tae Keun Yoo and Joon Yul Choi contributed equally to the work presented here and should be regarded as equivalent authors. JYC, IHR, and TKY developed the algorithms. JKK, ISL, and TKY consolidated the data and performed data analyses. JYC and TKY drafted the manuscript. IHR and JKK conceived and designed the study. All authors contributed to the revisions and finalization of the submitted manuscript. All authors met the following criteria: (1) substantial contribution to the conception or design of the work or the acquisition, analysis, or interpretation of the data; (2) drafting the work or critically revising it for important intellectual content; (3) final approval of the completed version; and (4) accountability for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work were appropriately investigated and resolved.

Corresponding author

Correspondence to Tae Keun Yoo.

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Ethical approval

All procedures of studies involving human participants were performed in accordance with the ethical standards of the Institutional Review Board of the Korean National Institute for Bioethics Policy (KNIBP No. 2023–0088-001) and the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Informed consent

The Institutional Review Board waived the requirement for informed consent because the data were fully de-identified to protect patient confidentiality.

Competing interests

Ik Hee Ryu and Jin Kuk Kim are directors of VISUWORKS and own company stock. Ik Hee Ryu serves on the Advisory Board of Carl Zeiss Meditec AG and Avellino Lab USA/MAB for Avellino Lab Korea. Jin Kuk Kim is an executive of the Korea Intelligent Medical Industry Association (KIMIA). Tae Keun Yoo is an employee of VISUWORKS and receives salary and stock as part of the standard compensation package. The authors declare no conflicts of interest. VISUWORKS has received research grants for SMILE surgery from Carl Zeiss Meditec AG, Germany. The research grants had no effect on this study.

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Choi, J.Y., Kim, H., Kim, J.K. et al. Deep learning prediction of steep and flat corneal curvature using fundus photography in post-COVID telemedicine era. Med Biol Eng Comput 62, 449–463 (2024). https://doi.org/10.1007/s11517-023-02952-6

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