Early peripheral laser photocoagulation of nonperfused retina improves vision in patients with central retinal vein occlusion (Results of a proof of concept study)

Abstract

To evaluate the effect of combination of ranibizumab and laser photocoagulation to peripheral retinal areas of nonperfusion in patients with non-ischemic central retinal vein occlusion (CRVO) without neovascularizations. This prospective, proof of concept study randomized 22 CRVO patients into two arms. The RL group (ranibizumab + laser; n = 10) received ranibizumab with additive laser photocoagulation; the control R group (n = 12) was treated with ranibizumab only. All patients received three initial monthly ranibizumab injections followed by PRN regimen. Changes in best corrected visual acuity (BCVA) and in central retinal thickness (CRT) were documented over 6 months. Median of BCVA improved in the RL group from 65 ETDRS letters (interquartile range IQR = 10 letters) at baseline to 70 (IQR = 23.2) letters at month 6. In the control group BCVA remained stable [baseline: 61 (IQR = 19.5) and month 6: 61 (IQR = 22) letters]. CRT decreased between baseline and final visit in the RL group from 547 (IQR = 513) μm to 246.5 (IQR = 346.3) μm, and in the control group from 637.5 (IQR = 344) μm to 423 (IQR = 737) μm. More pronounced improvements in BCVA were seen in the RL group (medians = 14 vs. 6.5 letters) although the observed group differences were not statistically significant due to small samples. The selective laser photocoagulation of peripheral areas of nonperfusion seems to lead to additional visual improvement in patients with CRVO. A larger replication trial is necessary to confirm the results of this proof of concept study.