Abstract
Purpose :
To evaluate the association between subfoveal choroidal thickness (SFCT) and branch retinal vein occlusion (BRVO) eyes treated with anti-vascular endothelial growth factor (anti-VEGF) therapy. Since the choroid plays a primary role in perfusing the outer retina and photoreceptors, the primary objective of our study was to evaluate initial choroidal thickness as a predictor for visual recovery in patients with macular edema secondary to BRVO.
Methods :
This was a retrospective consecutive case series of patients who were newly diagnosed with treatment naïve BRVO and treated with 3 monthly anti-VEGF injections at the Wills Eye Institute. All patients received enhanced depth imaging spectral domain optical coherence tomography scans to determine SFCT and central macular thickness (CMT). Baseline predictors (particularly SFCT) for functional response (best-corrected visual acuity gain ≥2 lines) were assessed at 3 months follow up using univariate and multivariate analysis.
Results :
A total of 40 eyes from 39 patients were included. Mean baseline SFCT was higher in functional responders (240.4 ± 73.1µm), compared to both non-responders (193.3 ± 63.6 µm; P=0.036) and their corresponding fellow eye (202.2 ± 67.1 µm; P=0.022). However, there was no difference in baseline SFCT between the non-responder BRVO eyes and their fellow eye (195.5 ± 62.0 µm; P=0.876). A higher baseline SFCT (for every 100 µm increase in SFCT) was found to be a positive predictor for functional response (regression coefficient: 1.1; P=0.03) on univariate analysis but not multivariate analysis.
Conclusions :
Treatment-naïve patients with BRVO who have a thicker baseline choroidal thickness compared to their fellow eye were more likely to have improved short-term visual outcomes following anti-VEGF therapy compared to patients with an initial choroidal thickness that is similar to their fellow eye. One hypothesis is that patients with a greater initial choroidal thickness are more likely to have intact perfusion to the outer retinal layers and therefore have a greater potential for visual gains following treatment of macular edema. Conversely, a thinner baseline choroidal thickness may be indicative of a more ischemic process and poorer perfusion to the outer retinal layers with less potential for visual recovery. Thus, initial SFCT may be a predictor for visual outcomes in patients receiving anti-VEGF therapy for BRVO.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.