Research Article

Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging

Volume: 52 October 6, 2026
TR EN

Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging

Abstract

This study evaluated the interocular agreement and within-eye repeatability of cone photoreceptor metrics measured using a confocal cone analysis system in healthy young adults, as well as their associations with ocular dominance and axial length. This cross-sectional study included 94 eyes from 47 healthy participants. Cone density and cone diameter were measured from fovea-centered 3 × 3 mm images obtained using the MicroClear CRO system (MicroClear Biomedical Co., Ltd., Suzhou, China). Magnification-corrected and original uncorrected cone measurements were analyzed. Interocular agreement was assessed using paired comparisons, intraclass correlation coefficients (ICC), and Bland–Altman analysis. Within-eye repeatability was evaluated from two repeated measurements per eye using the within-subject standard deviation, coefficient of repeatability (CoR), ICC, and Bland–Altman analysis. Associations with axial length were examined using Spearman correlation and generalized estimating equation (GEE) models. No significant interocular differences were observed for magnification-corrected cone density (mean difference, −763 cells/mm²; 95% confidence interval [CI], −2,799 to 1,273; p = 0.455; ICC = 0.679) or cone diameter (mean difference, 0.07 μm; 95% CI, −0.12 to 0.27; p = 0.455; ICC = 0.359). After exclusion of four measurements with automated segmentation failure, within-eye repeatability was good for both cone density (CoR = 4,937 cells/mm²; ICC = 0.924) and cone diameter (CoR = 0.40 μm; ICC = 0.941). Cone photoreceptor parameters were also similar between dominant and nondominant eyes. At the participant level, magnification-corrected cone density showed a moderate negative correlation with axial length (Spearman ρ = −0.545; p < 0.001), and this association remained significant in the adjusted GEE model (β = −5,914.39 cells/mm²/mm; 95% CI, −8,567.73 to −3,261.06; p < 0.001). In contrast, axial length was not significantly associated with uncorrected cone density in either the participant-level correlation analysis (Spearman ρ = −0.121; p = 0.419) or the adjusted GEE model (β = −1,798.92 cells/mm²/mm; 95% CI, −4,104.46 to 506.62; p = 0.126). These findings indicate good within-eye repeatability after exclusion of segmentation-failure measurements, while the association between axial length and cone density was sensitive to the magnification-correction procedure and should therefore be interpreted cautiously.

Keywords

Ethical Statement

Ethics Committee Decision No. 97, Decision Date: August 27, 2025

References

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Details

Primary Language

English

Subjects

Ophthalmology

Journal Section

Research Article

Publication Date

October 6, 2026

Submission Date

June 8, 2026

Acceptance Date

September 12, 2026

Published in Issue

Year 2026 Volume: 52

APA
Karaca, S., Kızılay, O., Kırık, F., Batu Oto, B., & Çelik, G. (2026). Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging. Journal of Uludağ University Medical Faculty, 52. https://doi.org/10.32708/uutfd.1966222
AMA
1.Karaca S, Kızılay O, Kırık F, Batu Oto B, Çelik G. Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging. J Uludag Univ Med Fac. 2026;52. doi:10.32708/uutfd.1966222
Chicago
Karaca, Serap, Osman Kızılay, Furkan Kırık, Bilge Batu Oto, and Gökhan Çelik. 2026. “Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging”. Journal of Uludağ University Medical Faculty 52 (October). https://doi.org/10.32708/uutfd.1966222.
EndNote
Karaca S, Kızılay O, Kırık F, Batu Oto B, Çelik G (October 1, 2026) Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging. Journal of Uludağ University Medical Faculty 52
IEEE
[1]S. Karaca, O. Kızılay, F. Kırık, B. Batu Oto, and G. Çelik, “Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging”, J Uludag Univ Med Fac, vol. 52, Oct. 2026, doi: 10.32708/uutfd.1966222.
ISNAD
Karaca, Serap - Kızılay, Osman - Kırık, Furkan - Batu Oto, Bilge - Çelik, Gökhan. “Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging”. Journal of Uludağ University Medical Faculty 52 (October 1, 2026). https://doi.org/10.32708/uutfd.1966222.
JAMA
1.Karaca S, Kızılay O, Kırık F, Batu Oto B, Çelik G. Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging. J Uludag Univ Med Fac. 2026;52. doi:10.32708/uutfd.1966222.
MLA
Karaca, Serap, et al. “Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging”. Journal of Uludağ University Medical Faculty, vol. 52, Oct. 2026, doi:10.32708/uutfd.1966222.
Vancouver
1.Serap Karaca, Osman Kızılay, Furkan Kırık, Bilge Batu Oto, Gökhan Çelik. Preliminary Evaluation of Interocular Agreement and Biometric Associations of Cone Photoreceptor Metrics in Healthy Young Adults Using Confocal Retinal Imaging. J Uludag Univ Med Fac. 2026 Oct. 1;52. doi:10.32708/uutfd.1966222

ISSN: 1300-414X, e-ISSN: 2645-9027

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