Relationship between Outer Retinal Layers Thickness and Visual Acuity in Diabetic Macular Edema

Area of Science:

• Ophthalmology
• Medical Imaging
• Retinal Diseases

Background:

• Diabetic macular edema (DME) is a leading cause of vision loss in diabetic patients.
• Accurate assessment of visual function and prognostic factors is crucial for managing DME.
• Optical Coherence Tomography (OCT) is a key imaging modality for evaluating retinal structure in DME.

Purpose of the Study:

• To determine the correlation between outer retinal layers (ORL) thickness and visual acuity (VA) in patients with DME.
• To compare the predictive value of ORL thickness versus total retinal thickness on visual outcomes.
• To explore the potential of ORL thickness as a novel prognostic biomarker for DME.

Main Methods:

• Consecutive patients diagnosed with DME were recruited from a university retina clinic.
• Optical Coherence Tomography (OCT) was performed to assess retinal structure.
• Outer retinal layers (ORL) thickness was measured as the distance between the external limiting membrane (ELM) and retinal pigment epithelium (RPE) at the foveal center.
• Correlation coefficients were calculated between total retinal thickness, ORL thickness, and visual acuity (VA).

Main Results:

• The study included 78 patients with DME (mean age 58.1 years).
• A significant positive correlation was found between total retinal thickness and VA (r=0.34, P < 0.001).
• Outer retinal layers (ORL) thickness demonstrated a stronger correlation with VA (r=0.65, P < 0.001) compared to total retinal thickness.

Conclusions:

• Outer retinal layers (ORL) thickness is a more significant predictor of visual acuity than overall retinal thickness in DME patients.
• ORL thickness represents a novel and valuable OCT parameter for assessing DME.
• This measurement may serve as a potential long-term prognostic factor for visual outcomes in individuals with DME.