Macular laser photocoagulation guided by spectral-domain optical coherence tomography versus fluorescein angiography for diabetic macular edema

Background: The aim of this study was to compare the efficacy of spectral-domain optical coherence tomography (SD-OCT) and fluorescein angiography (FA) in the guidance of macular laser photocoagulation for diabetic macular edema. Methods: This was a prospective interventional clinical comparative pilot study. Forty eyes from 24 consecutive patients with diabetic macular edema were allocated to receive laser pho- tocoagulation guided by SD-OCT or FA. Best-corrected visual acuity (BCVA), central macular thickness, and retinal volume were assessed at baseline and two months after treatment. Results: Subjects treated using FA-guided laser improved BCVA from the logarithm of the minimum angle of resolution (logMAR) 0.52 ± 0.2 to 0.37 ± 0.2 (P, 0.001), and decreased mean central macular thickness from 397.25 ± 139.1 to 333.50 ± 105.7 μm (P< 0.001) and retinal volume from 12.61 ± 1.6 to 10.94 ± 1.4 mm³ (P< 0.001). Subjects treated using SD-OCT guided laser had improved BCVA from 0.48 ± 0.2 to 0.33 ± 0.2 logMAR (P< 0.001), and decreased mean central macular thickness from 425.90 ± 149.6 to 353.4 ± 140 μm (P< 0.001) and retinal volume from 12.38 ± 2.1 to 11.53 ± 1.1 mm³ (P< 0.001). No significant differences between the groups were found in two-month BCVA (P = 0.505), two-month central macular thickness (P = 0.660), or two-month retinal volume (P = 0.582). Conclusion: The short-term results of this pilot study suggest that SD-OCT is a safe and effective technique and could be considered as a valid alternative to FA in the guidance of macular laser photocoagulation treatment for diabetic macular edema.