Optical Coherence Tomographic Patterns as Predictors of Structural Outcome After Intravitreal Ranibizumab in Diabetic Macula Edema.

Background/objectives: The purpose of this study was to present an association between the treatment response of diabetic macular edema (DME) to intravitreal ranibizumab (IVR) injections and different morphology patterns using spectral domain optical coherence tomography (SD-OCT).

Subjects/methods: This retrospective study included 216 eyes of 142 subjects who received IVR for DME and were observed for at least 2 years. Medical charts and SD-OCT images of consecutive patients were reviewed at baseline, 1, 3, 6, 12, and 24 months after first IVR treatment. The OCT patterns were characterized as diffuse retinal thickening (DRT), cystoid macular edema (CME), serous retinal detachment (SRD), and vitreomacular interface abnormalities (VMIAs). All patients were classified into four groups based on the OCT findings.

Results: For a total of 216 eyes, 36 eyes were classified into the DRT group, 76 in the CME group, 42 in the SRD group, and 62 in the VMIA group. There were significant central macula thickness (CMT) improvements in all groups at the 1st month and the 2nd year, except for the DRT group at the 2nd year. Patients with OCT findings of hyperreflective dots (HRDs), metabolic parameters of hyperlipidemia, and coronary artery disease (CAD) had significantly less improvements in CMT at 2-year follow-up (=0.029, 0.007, <0.001, respectively).

Conclusion: A trend toward decreased effectiveness after long-term IVR treatment was observed in the DRT group. Consistent IVR treatment could still achieve favorable improvement in the reduction of CMT in 2-year follow-up in the VMIA group. Different OCT patterns in DME may affect the therapeutic role of anti-VEGF agents and predict the structure outcome.