Longitudinal changes in choroidal thickness in branch retinal vein occlusion with and without cystoid macular edema

Abstract

Purpose : Recent studies have implicated a role for the choroidal circulation in the recovery of visual function in branch retinal vein occlusion (BRVO), but few have longitudinally followed choroidal thickness (CT) and correlated this with visual function in BRVO patients. Our study describes initial CT and the change in CT over time between BRVO and unaffected fellow eyes, the effect of intravitreal injections on CT in BRVO eyes, and the correlation of CT with corrected visual acuity (VA) in BRVO eyes.

Methods : Demographic data and enhanced depth imaging optical coherence tomography (EDI-OCT) images were collected for BRVO as well as for unaffected fellow eyes. Manual measurements of subfoveal CT were made at initial and final clinic visits and were compared between BRVO and fellow eyes, BRVO eyes with and without cystoid macular edema (CME), and before and after treatment in BRVO eyes using paired t-tests.

Results : A total of 105 patients with BRVO with (n = 70) and without (n = 35) CME were included in the study. Most patients (72.4%, 77/105) presented to our institution more than 6 months after symptom onset. Median follow-up of all 105 patients was 19.0 months. At the initial visit, there was no statistically significant difference in CT between BRVO and unaffected fellow eyes; however, the mean difference in CT was statistically significant in patients with BRVO onset within 6 months of presentation (BRVO, 216±59 mm; fellow, 195±58 mm; p = 0.016). CT was greater in BRVO eyes versus fellow eyes whether or not CME was present at baseline, if patients presented within 6 months of BRVO onset (p < 0.001 and p = 0.025, respectively). Both CT and VA in BRVO eyes with CME that were treated with intravitreal anti-VEGF and/or steroid injections did not change significantly by the final visit, but most of these eyes were still actively undergoing treatment.

Conclusions : CT was significantly greater in BRVO eyes within 6 months of symptom onset, regardless of whether macular edema was present. However, CT was similar to fellow eyes when BRVO occurred more than 6 months prior to patient presentation. CT and VA did not significantly change with intravitreal injections, but most were still actively undergoing treatment at the final visit. Further longitudinal studies are needed to better understand the relationship between CT and visual recovery in BRVO patients.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.