Early retinal, optic disc and choriocapillaris microvascular alterations in children with type 1 diabetes without clinical retinopathy: an OCTA-based case-control study.
Children with type 1 diabetes without clinical retinopathy may show early microvascular alterations on OCTA, particularly increased central choriocapillaris non-perfusion and reduced intrapapillary vessel density.
Key Findings
Results
Choriocapillaris non-perfused area (NPCA) ratio was significantly increased in children with type 1 diabetes compared to healthy controls.
The study included 77 children with T1DM and 77 healthy controls in a cross-sectional, case-control design.
One eye from each participant was analyzed using OCTA.
The difference in choriocapillaris NPCA ratio between groups was statistically significant (p < 0.05).
None of the children with T1DM had clinically detectable retinopathy at the time of assessment.
Results
Intrapapillary vessel density was lower in children with type 1 diabetes compared to healthy controls.
Radial peripapillary capillary vessel density in the peripapillary region and whole-image analysis showed no significant differences between groups (p > 0.05).
The reduction was specific to the intrapapillary region (p < 0.05).
This finding suggests early optic disc microvascular involvement preceding clinical retinopathy.
Results
Foveal thickness was increased in children with type 1 diabetes compared to controls.
The difference in foveal thickness between the T1DM and control groups was statistically significant (p < 0.05).
Subfoveal choroidal thickness showed no significant difference between groups (p > 0.05).
Foveal thickness was measured using optical coherence tomography (OCT).
Results
Superficial capillary plexus vessel density and foveal avascular zone parameters did not differ significantly between the T1DM and control groups.
Comparisons of superficial capillary plexus vessel density yielded p > 0.05 across all regions.
Foveal avascular zone area was also comparable between groups (p > 0.05).
These null findings suggest that superficial retinal microvascular changes may not yet be detectable at this stage of disease.
Results
Deep capillary plexus vessel density was largely comparable between groups, with the exception of a higher superior hemi-area vessel density in the T1DM group on unadjusted analysis.
Deep capillary plexus vessel density was similar between groups across most regions (p > 0.05).
Superior hemi-area vessel density was higher in the T1DM group on unadjusted analysis (p < 0.05).
This finding was noted specifically on unadjusted analysis, implying potential confounding factors.
Methods
The study design included recording of disease duration and daily insulin dose in the T1DM group alongside HbA1c levels to characterize the diabetic cohort.
The study was cross-sectional and included 154 children total (77 T1DM, 77 controls).
Age, sex, body mass index, and HbA1c levels were recorded for all participants.
Disease duration and daily insulin dose were additionally recorded for the T1DM group.
All children with T1DM had no clinical retinopathy, representing a preclinical ocular disease stage.
What This Means
This research suggests that children with type 1 diabetes can develop subtle changes in the tiny blood vessels of their eyes even before any signs of diabetic eye disease (retinopathy) are visible during a standard eye exam. Using a specialized imaging technology called optical coherence tomography angiography (OCTA), researchers compared the eye vasculature of 77 children with type 1 diabetes to 77 healthy children of similar age and sex. They found that the diabetic children had reduced blood vessel density in the optic disc (the area where the optic nerve connects to the eye), reduced blood flow in the layer beneath the retina called the choriocapillaris, and slightly increased retinal thickness at the center of vision — all without any visible retinopathy.
Interestingly, not all vascular layers showed changes: the superficial blood vessel layer of the retina and the foveal avascular zone (a small central area normally free of blood vessels) appeared normal in the diabetic children, suggesting that different layers of the eye may be affected at different stages of disease progression. The choriocapillaris and optic disc appear to be among the earliest sites of microvascular damage in pediatric type 1 diabetes.
This research suggests that OCTA could be a valuable tool for detecting early, subclinical eye damage in children with type 1 diabetes before it becomes visible through conventional examination. Identifying these changes early may help in monitoring disease progression and potentially guiding preventive strategies, though further longitudinal studies are needed to understand whether these early changes predict future retinopathy.
Bolat S, Sönmez &, Topuz H, Özbaş M. (2026). Early retinal, optic disc and choriocapillaris microvascular alterations in children with type 1 diabetes without clinical retinopathy: an OCTA-based case-control study.. BMC ophthalmology. https://doi.org/10.1186/s12886-026-04888-5