Anatomic Biomarkers of Macular Edema Associated with Retinal Vein Occlusion

Purpose: To assess the relationship between best-corrected visual acuity (BCVA) and anatomic features in patients with macular edema (ME) related to retinal vein occlusion (RVO).

Design: Post hoc analysis of 3 clinical trials, which included verified diagnoses, protocol refractions, and the assessment of OCT and fluorescein angiography (FA) images at a masked reading center.

Participants: Patients diagnosed with RVO-ME.

Methods: Correlation analyses were performed to determine the correlation between BCVA and macular anatomy at baseline and at 12 and 24 weeks and between changes from baseline to 12 and 24 weeks.

Main outcome measures: The correlations between BCVA and central subfield thickness (CST), ellipsoid zone (EZ) integrity, intraretinal fluid (IRF), subretinal fluid, central leakage, and ischemia were assessed.

Results: In a total of 828 eyes with RVO-ME, the mean age, BCVA, and CST at baseline was 64.7 years, 51.1 letters, and 656.9 μm, respectively. At baseline, a moderate negative correlation was observed between BCVA and CST (r = - 0.56, P < 0.001). At weeks 12 and 24, the mean BCVA of eyes with definitely abnormal (absent) EZ was statistically significantly worse than that of eyes with normal EZ. At week 12, a moderate negative correlation was observed between changes in BCVA and changes in CST (r = - 0.35, P < 0.001), with a similar degree of association noted at week 24 (r = - 0.35, P < 0.001). At weeks 12 and 24, eyes that showed any improvement in central IRF showed a greater improvement in BCVA than eyes that showed no improvement worsening (week 12: 463 eyes, 18.3 letters vs. 177 eyes, 13.0 letters, respectively, P < 0.001) and (week 24: 332 eyes, 20.2 letters vs. 131 eyes, 13.3 letters, respectively, P < 0.001). With respect to the correlation between baseline BCVA and fluorescein leakage or capillary nonperfusion, the Pearson correlation coefficients were - 0.41 (P < 0.001) and - 0.16 (P = 0.060), respectively.

Conclusions: In addition to CST, there are important clinically relevant relationships between BCVA and both OCT and FA anatomic features in patients with RVO-ME.