Effect of optical coherence tomography biomarkers on treatment outcomes in patients with diabetic macular edema.

PURPOSE: This study aimed to evaluate pre-treatment optical coherence tomography (OCT) biomarkers in patients with diabetic macular edema (DME) and to assess changes in these parameters and their impact on visual prognosis one year after intravitreal (IV) anti-VEGF and steroid treatment.

METHODS

This retrospective study included 250 eyes of 250 patients with DME. Best-corrected visual acuity (BCVA) and routine ophthalmologic examinations were evaluated at baseline and at 4, 6, and 12 months after treatment. Spectral-domain OCT biomarkers assessed were central macular thickness (CMT), serous retinal detachment (SRD), disorganization of retinal inner layers (DRIL), hyperreflective dots (HRD), integrity of the ellipsoid zone (EZ) and external limiting membrane (ELM), intraretinal cyst (IRC) size, vitreomacular adhesion (VMA), epiretinal membrane (ERM), and macular cube volume (MCV). Patients were classified according to letter gain as good (> 10 letters), moderate (5-10 letters), or poor (< 5 letters) responders. Statistical analyses included one-way ANOVA and Kruskal-Wallis tests with post-hoc multiple comparisons.

RESULTS

BCVA improved significantly at 4, 6, and 12 months after treatment (p < 0.001). Mean CMT, IRC, HRD, and MCV values showed significant reductions at all follow-up visits (p < 0.001). The good responder group had significantly lower baseline BCVA and higher baseline CMT, IRC, and HRD values (p < 0.001). In contrast, the poor responder group showed a significantly higher baseline presence of DRIL (p < 0.001).

CONCLUSION

IV anti-VEGF and dexamethasone treatments provide significant anatomical and functional improvement in DME. High baseline CMT, HRD, and IRC values may indicate a favorable visual prognosis, whereas the presence of DRIL at baseline is associated with limited visual gain. Providing accurate prognostic information at treatment initiation may improve patient compliance.