Investigation of choroidal structure changes after intravitreal anti-VEGF therapy for retinal vein occlusion.

Background: We aimed to investigate the effect of retinal vein occlusion (RVO) on the posterior segment structures of the eye and its changes with intravitreal anti-Vascular Endothelial Growth Factor (VEGF) treatment.

Methods: This prospective longitudinal study included 29 eyes of 29 patients with RVO (17 males and 12 females) followed for 6 months. The best corrected visual acuity (BCVA), macula, choroid ticknesses and choroidal vascularity index (CVI) obtained by spectral-domain optical coherence tomography were recorded at baseline and the first, third, and sixth months after the first injection. Results were compared with fellow eyes (non-affected eyes) and age- and sex-matched controls.

Results: BCVA increased significantly in the 6th month, more in the first month of injection (p < 0.05 for each). Central macular tickness, subfoveal choroid tickness, stromal and total area of choroid decreased significantly after injection (p < 0.05 for each). CVI values increased significantly, especially in the 1st month after injection (p < 0.05 for each). In eyes with Branch RVO, there was a significant decrease in the macular thickness of the occlusive areas with treatment, while there was no statistically significant change in the non-occlusive macular thickness.

Conclusion: Observation of changes in choroidal structure may be useful to assess the activity of RVO and predict the efficacy of anti-VEGF therapy.