Outcome indicators differ between patients with CRVO versus BRVO

This study presents outcomes of patients treated with ranibizumab for branch and central retinal vein occlusion (BRVO and CRVO).

Study design

This post hoc analysis included patients from the BRAVO and CRUISE clinical trials who completed 12-months of follow-up in the HORIZON extension trial. Two hundred and five eyes with BRVO and 181 eyes with CRVO met the criteria and were included. The primary outcome measures were visual acuity (≥20/40), visual acuity gain (≥15 letters) and central subfield thickness (CST; ≤250 μm) at 12 months.

Outcomes

In patients with BRVO, statistically significant predictors of a 15-letter gain were good baseline BCVA, male sex and normal hematocrit. Extensive subretinal fluid at baseline correlated with the final CST.

For individuals with CRVO, good baseline BCVA, never smoking, and young age were indicators of good final BCVA, while poor baseline BCVA, hypertension and low diastolic ocular perfusion pressure correlating with a 15-letter gain. The final CST in CRVO patients was linked to lower hematocrit, high systolic ocular perfusion, large areas of central hemorrhage and no subretinal fluid.

Limitations

This was a post hoc analysis of an extension trial.

Clinical significance

These findings probably reflect the pathophysiologic differences between BRVO and CRVO. The hematocrit associations were interesting: Low hematocrit and anemia were poor prognostic signs for BRVO, but hemodilution may, along with high systolic and low diastolic perfusion pressure, improve outcomes in CRVO by improving ocular blood flow. The authors suggest that perhaps initial aggressive lowering of systolic blood pressure is not advisable for CRVO.