Retinal vein occlusion (RVO) is fairly easy to see funduscopically, but for a more nuanced understanding of a patient’s condition and prognosis, OCT can provide much useful information, New research links the condition to increased retinal thickness and the presence of subretinal fluid and hyperreflective foci. The cross-sectional, post-hoc analysis included OCT images from two prospective, multicenter studies that enrolled 381 and 301 treatment-naïve patients with branch RVO (BRVO) and central RVO (CRVO), respectively.

Of all parameters studied, only central subfield thickness and age were consistently associated with worse best-corrected visual acuity (BCVA) in treatment-naïve RVO patients, the research team from Austria noted.

Considering all OCT biomarkers included in the investigation, an increase in central retinal thickness was associated with a loss in baseline BCVA of up to -3.4 ETDRS letters and was related to an accumulation of intraretinal (98%) and subretinal fluid (54%).

In the BRVO group, the researchers observed statistically significant associations between BCVA and a 100µm increase in central subfield thickness (-3.1 letters), intraretinal cysts at center point (+4.1), subretinal fluid at center point (+3.0) and hyper-reflective foci at the central B-scan (-2.2). For patients with CRVO, a 100µm increase in central subfield thickness was associated with a loss of -3.4 letters.

In the total cohort, a 100µm increase in central subfield thickness, subretinal fluid at center point and hyper-reflective foci at the central B-scan correlated with a difference of -3.2,+3.2 and -2.0 letters, respectively. Additionally, a 10-year increase in age and female gender resulted in a -2 and -2.5 letter decrease in the total cohort, respectively.

Morphology on OCT explained only a modest part of functional loss, the researchers said.