Retinal Thickness Deviation: A New OCT Parameter for Assessing Diabetic Macular Edema.

Area of Science:

• Ophthalmology
• Retinal Imaging
• Diabetic Retinopathy

Background:

• Diabetic macular edema (DME) is a leading cause of vision loss in diabetic patients.
• Intravitreal therapy is a common treatment for DME, but predicting visual outcomes remains crucial.
• Retinal thickness deviation (RTD) is a novel metric to assess retinal changes.

Purpose of the Study:

• To evaluate the "retinal thickness deviation" (RTD) in eyes with DME treated with intravitreal therapy.
• To determine the association between RTD and best-corrected visual acuity (BCVA) over two years.
• To compare the predictive power of RTD versus central subfield thickness (CST) on visual outcomes.

Main Methods:

• Retrospective analysis of 104 eyes with DME undergoing intravitreal therapy.
• Collected BCVA and CST data at baseline, 12 months, and 24 months.
• Calculated RTD as the difference between measured and normative CST; performed linear regression analyses.

Main Results:

• RTD significantly decreased over 24 months of treatment (p < 0.001).
• RTD showed a substantial association with BCVA at 24 months (R² = 0.272, p < 0.001).
• CST association with BCVA weakened over time, becoming weak at 24 months (R² = 0.065, p = 0.009).

Conclusions:

• RTD is a valuable indicator of visual outcomes in DME patients treated with intravitreal therapy.
• RTD demonstrates a stronger and more consistent association with BCVA compared to CST over two years.
• RTD may serve as a more reliable biomarker for monitoring treatment response and predicting visual prognosis in DME.