Objective: To evaluate short-term markers of outcome in diabetic macular edema (DME).
Methods: Prospective interventional case series included 122 eyes of 122 patients with recently diagnosed DME. Eyes were treated with a 3-monthly loading dose of ranibizumab or aflibercept and pro re nata thereafter. Serial enhanced deep imaging SD-OCT high resolution scans were used to measure subfoveal choroidal thickness (SFCT) and central retinal thickness (CRT). Anatomic (10% CRT decrease) and functional responses (best corrected visual acuity, BCVA gain ≥5 letters) were assessed at 3 months and 6 months using univariate and multivariate analyses. Parameters tested were gender, duration of diabetes, HbA1c, hypertension, CRT, SFCT, BCVA, ellipsoid zone (EZ) status, subfoveal neuroretinal detachment (SND), anti-VEGF used and laser naivety. A logistic regression model was applied to find independent markers outcome.
Results: BCVA increased, CRT and SFCT decreased at 3 months and 6 months. Good metabolic control (p = 0.003), intact baseline EZ (p = 0.030), EZ re-grading at 3 M (p < 0.001) and laser naivety (p = 0.001) were associated with better functional outcome. The multivariate linear regression model showed that baseline SND and CRT are predictors of anatomic response, while lower baseline BCVA and intact EZ are predictors of functional response.
Conclusion: The presence of SND predicts anatomic response only, while an intact EZ is critical to achieve a good functional outcome in DME.
Keywords: Anti-vascular endothelial growth factor; Diabetic macular edema; Laser; Outcome factors; Spectral-domain optical coherence tomography.