CORRELATION BETWEEN INTRA-RETINAL CYST DIMENSIONS AND VISION IN DME: AN OCT-BASED STUDY

This retrospective, cross-sectional study aimed to evaluate the correlation between intra-retinal cyst dimensions and best-corrected visual acuity (BCVA) in diabetic macular edema (DME) patients using spectral-domain optical coherence tomography (OCT). Eighty-two eyes of 82 patients with type 2 diabetes mellitus and diabetic retinopathy were included, meeting the criterion of BCVA ≥ 20/200. Patients were categorized into two groups: DME without cysts (n = 38) and DME with intra-retinal cysts (n = 44). Exclusion criteria included prior macular grid laser photocoagulation, pars plana vitrectomy, significant media opacity, other ocular conditions impeding OCT assessment, or incomplete records. Comprehensive ophthalmic evaluation included BCVA measurement (logMAR), slit-lamp biomicroscopy, Goldmann applanation tonometry, fundoscopy, and OCT measurement of central macular thickness (CMT) and cyst dimensions. Mean BCVA was significantly worse in the cyst group (0.74 ± 0.15) compared to the non-cyst group (0.46 ± 0.12; p < 0.001), and mean CMT was significantly greater (398 ± 46 μm vs. 322 ± 34 m; p < 0.001). Vertical cyst size demonstrated a strong positive correlation with BCVA (r = 0.64, 95% CI: 0.48–0.76; p < 0.001), while horizontal cyst size showed a moderate correlation (r = 0.59, 95% CI: 0.42–0.73; p < 0.001). Larger cysts were associated with disruption of the outer retinal layers, particularly the ellipsoid zone, contributing to poorer vision. These findings suggest that intraretinal cyst size is a valuable prognostic biomarker in DME, and OCT-based assessment could guide timely intervention, including early initiation or intensification of anti-VEGF or corticosteroid therapy to preserve vision. Further prospective studies are warranted to validate these results and assess treatment outcomes based on cyst dimension monitoring.