Can Spectral-Domain Optical Coherence Tomography Findings Forecast Visual Outcome in the Case of Macular Edema?

Purpose: To evaluate the relationship between visual outcome and the photoreceptor inner segment/outer segment (IS/OS) layer status in patients with macular edema of any etiology. Design: Cross-sectional study Patients with macular edema of any etiology and who did not present with a disrupted IS/OS line were enrolled. We obtained simultaneous visual acuity and optical coherence tomography (OCT) of patients with macular edema using a spectral-domain (SD) OCT system. The device recorded retinal thickness on tomography. SD OCT was recorded repeatedly in patients before and after treatment with an anti-vascular endothelial growth factor agent or triamcinolone, and the central thickness, IS, and OS were measured. The IS/OS ratio was calculated, and the data were analyzed statistically. We also reviewed the OCT scans to determine the type of macular edema, i.e., cystoid macular edema or diffuse macular edema (absence of any cysts). Results: Forty-eight patients (48 eyes: 21 male and 27 female; median age, 58.50 ± 10.8 years) with macular edema were enrolled. Twenty-seven eyes had cystoid macular edema, and 10 eyes had diffuse macular edema. The median central subfield thickness was 462 ± 150.3 μm. The IS/OS layer was observed in all 48 eyes, and the IS/OS ratio was calculated. Eight (16.7%), 11 (22.9%), and 29 (60.4%) eyes had venous tributary occlusion, post-cataract cystoid macular edema, and diabetic macular edema, respectively. There was a significant difference between pre- and post-treatment vision (p = 0.001, Table 2). When we compared the pre and post treatment IS, OS, and IS/OS ratio with t test (p = 0.000 with 95% CI). The presenting vision differed significantly according to the IS/OS ratio (p = 0.010, Table 3). Conclusion: This study demonstrated that the IS/OS ratio is not significantly correlated with final visual acuity following treatment for macular edema.