Quantitative assessment of macular contraction and vitreoretinal interface alterations in diabetic macular edema treated with intravitreal anti-VEGF injections.

BACKGROUND: Macular contraction after anti-vascular endothelial growth factor (anti-VEGF) injections for diabetic macular edema (DME) was evaluated by documenting the displacement of macular capillary vessels and epiretinal membrane (ERM) formation.

METHODS: A total of 130 eyes were included in this retrospective study. The study group consisted of 63 eyes which had intravitreal anti-VEGF injections for DME, and the control group included 67 eyes without central DME. The study and the control groups were well balanced in terms of diabetes duration and HbA1c. The distances between the bifurcation of the macular capillary retinal vessels were measured, and ERM status was evaluated based on spectral-OCT findings on the initial and final visit.

RESULTS: In the study group, the mean number of injections was 4.7 ± 2.6 (3-14). The mean follow-up time was 16.7 ± 7.8 months in the study group whereas it was 20.7 ± 10.9 months in the control group (p = 0.132). The change in distance measurements between the reference points on macular capillary vessels was significant in all lines except line c (p < 0.05 for lines a, b, d, e, and f) in the study group whereas it was significant in only line e in the control group (p = 0.007, paired samples test). However, when the change in macular thickness was accounted as a confounding factor, the change in distances between the references points from the initial visit to the final visit lost its significance (repeated measures ANCOVA, p > 0.05). During follow-up, the number of cases with ERM changed from 10 to 12 in the study group whereas it remained three in the control group.

CONCLUSION: There was a displacement of macular capillary vessels which was associated with the change in macular thickness in eyes having anti-VEGF injections for DME. The number of ERM cases did not change significantly during the follow-up.