Retinal Neural Layer Thickness and Contrast Sensitivity in Type 2 Diabetes Without Clinical Retinopathy: A Cross-Sectional Study
DOI:
https://doi.org/10.37275/bsm.v10i7.1660Keywords:
Contrast sensitivity, Diabetic retinal neurodegeneration, Ganglion cell-inner plexiform layer, Optical coherence tomography, Retinal nerve fiber layerAbstract
Background: Retinal neural dysfunction may occur in type 2 diabetes mellitus (T2DM) before clinically visible diabetic retinopathy.
Objective: We evaluated whether retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCL-IPL) thickness were associated with contrast sensitivity in adults with T2DM without clinical retinopathy.
Methods: This cross-sectional study included 30 eyes from 16 participants examined from September 2024 to June 2025. Swept-source optical coherence tomography measured average and quadrant RNFL thickness and macular GCL-IPL thickness. Monocular contrast sensitivity was assessed with the Pelli-Robson chart. Source-reported analyses included exploratory Spearman correlations, generalized estimating equations (GEE) for inter-eye clustering, and exploratory receiver operating characteristic (ROC) analysis.
Results: Mean RNFL thickness was 101.3 ± 12.55 µm, GCL-IPL thickness was 81.53 ± 7.34 µm, and contrast sensitivity was 1.773 ± 0.227 logCS. Eye-level correlations with contrast sensitivity were ρ=0.758 for GCL-IPL and ρ=0.640 for average RNFL (both source-reported p<0.001). In the exploratory GEE model, coefficients were 0.0104 logCS per µm for GCL-IPL (95% CI 0.001-0.019) and 0.0062 for RNFL (95% CI 0.001-0.011). Exploratory AUCs were 0.872 and 0.804, respectively.
Conclusion: Thicker GCL-IPL and RNFL measurements were associated with better contrast sensitivity in this small cohort. The estimates are hypothesis-generating and require confirmation with participant-level data, larger samples, and external validation before clinical use.
Authors
- Ramzi Amin1*
- Ririn Rahayu1
- Petty Purwanita1
- Muhammad Aulia Molid Ogest Putra Calisanie1
- 1Department of Ophthalmology, Faculty of Medicine, Universitas Sriwijaya / Dr. Mohammad Hoesin Central General Hospital, Palembang, Indonesia
Corresponding author Ramzi Amin — ramzi.amin26@gmail.com
Article history
- Submitted
- Accepted
- Published
Downloads
Published
Issue
Section
License
Copyright (c) 2026 Ramzi Amin, Ririn Rahayu, Petty Purwanita, Muhammad Aulia Molid Ogest Putra Calisanie

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Copyright and licensing
Copyright in each article remains with the author(s). Authors grant Bioscientia Medicina: Journal of Biomedicine and Translational Research a non-exclusive right of first publication and the right to identify itself as the original publisher. No exclusive transfer of copyright is required.
All articles are published under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License (CC BY-NC-SA 4.0): https://creativecommons.org/licenses/by-nc-sa/4.0/. Users may copy, redistribute, remix, transform, and build upon the material for non-commercial purposes, provided appropriate attribution is given, a link to the license is supplied, changes are indicated, and adaptations are distributed under the same license.
The license applies to the article's scholarly content unless a credit line states otherwise. Third-party material may be subject to separate rights. Authors retain patent, trademark, moral, and research-data rights. The copyright year follows the article's publication date.











