Abstract
Purpose :
To determine OCT morphological characteristics that can predict the response to anti-VEGF treatment of Diabetic Macular Edema (DME).
Methods :
Seventy-one patients with DME were enrolled in a prospective, observational study, following accepted clinical practice (NCT01947881-CHARTRES). Of these, 67 completed the study. All patients received monthly intravitreal injections of anti-VEGF Lucentis in the first 3 months. All patients underwent BCVA measurements by ETDRS protocol and SD-OCT (Cirrus HD-OCT 5000, Zeiss Meditec) at baseline, months 1, 2, 3 and 6 and Color Fundus Photography (CFP) and Fluorescein Angiography (FA) at baseline and months 3 and 6. The treatment response was characterized in groups according to the increase of BCVA letters: Good Responders (improvement of ≥ 10 letters), Moderate Responders (improvement between 5 letters and 10 letters) and Poor Responders (improvement of < 5 letters or loss of letters). The SD-OCT images were analyzed and graded by an independent Reading Center to obtain a morphological characterization of DME before and after treatment. Central Retinal Thickness (CRT), extension of Disorganization of the Retinal Inner Layers (DRIL), size of intraretinal cystoid spaces and extension of disruption of External Limitant Membrane (ELM), Ellipsoid Zone (EZ) and Retinal Pigment Epithelium (RPE), were quantified in the 1 mm area centered on the fovea.
Results :
Twenty-six patients (38.80%) were identified as Good Responders, 19 (28.35%) as Moderate Responders and 22 (32.83%) as Poor Responders. No significant differences regarding BCVA and central retinal thickness (CRT) were found at baseline between the 3 groups (p=0.176 and p=0.573 respectively). Higher values of DRIL area and disruption of external retinal layers at baseline, especially EZ and ELM layers, were significantly correlated with a poor response to treatment ((0.12; CI: 0.02- 0.59; P=0.009) (0.24; CI: 0.07- 0.86; P=0.029) and (0.21; CI: 0.04- 1.20; P=0.079, respectively). A poor response to treatment was also correlated with the presence of larger cystoid spaces in the 1 mm centered on fovea (80.95% of larger cysts in poor responders vs 46.15% in good responders).
Conclusions :
Higher values of DRIL area and disruption of external retinal layers, especially damage of the EZ and ELM are good predictors for BCVA response to anti-VEGF therapy in DME.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.