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.