Eye Asymmetry Signals Diabetic Retinopathy Severity
A retrospective study of 221 patients links differences between left and right eyes to the progression of diabetic retinopathy.
Updated on Nov. 3, 2026 in Diabetes
Researchers analyzed 442 eyes from 221 patients with the same stage of diabetic retinopathy in both eyes, published in Acta Ophthalmologica. Greater asymmetry in the foveal avascular zone of the superficial capillary plexus was linked to male sex, diabetic macular edema and increased disease severity.
Why it matters
The findings suggest that comparing the two eyes may reveal disease changes earlier than fundus examination can detect them. The authors indicate this asymmetry may have prognostic value and that both eyes should be evaluated in clinical trials for severe diabetic retinopathy.
The retrospective analysis of OCT angiography in 442 eyes from 221 patients found significantly larger foveal avascular zone area and perimeter in the left eye among 34 proliferative cases, while perfusion density, vessel density and fractal dimension showed no significant inter-eye differences. Whether this asymmetry reflects a causal vascular mechanism or predicts outcomes has not been established.
The players
Acta Ophthalmologica
Acta Ophthalmologica is a peer-reviewed international journal of ophthalmology published by the Scandinavian Ophthalmological Society and Wiley.
IRCCS MultiMedica
IRCCS MultiMedica is an Italian research hospital institution that conducts biomedical and clinical research.
The details
The researchers measured central subfield thickness, foveal avascular zone area and perimeter, perfusion density, vessel density and fractal dimension in both capillary plexuses. They calculated an asymmetry index for foveal avascular zone area and examined its association with demographic and clinical factors using regression models.
Timeline
Study results were published in Acta Ophthalmologica on November 3, 2026.
Health Landscape
Optical coherence tomography angiography has increasingly been used to quantify retinal microvasculature without dye injection. This study extends that approach by treating the fellow eye as an internal comparator for detecting disease severity in diabetic retinopathy.
Patients with diabetic retinopathy may benefit from having both eyes evaluated during follow-up, since asymmetry in retinal blood vessel measurements could appear before changes are visible on routine examination. Clinicians may consider this in monitoring disease progression, though the approach is not yet standard practice.
The takeaway
Comparing the two eyes in diabetic retinopathy may add a useful signal to routine assessment. Regular eye examinations remain essential for anyone living with diabetes.
Further reading
Explore more on Diabetes to see how eye complications relate to broader disease management.
