To investigate the additional beneficial effect of peripheral ischemic retinal photocoagulation besides intravitreal bevacizumab in macular edema due to ischemic central retinal vein occlusion (CRVO).

A randomized double-masked controlled clinical trial was designed to evaluate the efficacy of Intravitreal bevacizumab (IVB) injection with or without laser photocoagulation towards retinal nonperfusion area in ischemic CRVO. Therefore, 46 eyes of 46 treatment-naïve patients affected by ischemic CRVO were randomly selected and divided into two arms. The 22 patients in first group (IVB or group A) were treated with 3 consecutive monthly IVB and 24 individuals in the second group were administered IVB plus peripheral photocoagulation of nonperfused retina (group B or IVB+LASER). Further IVB injections were feasible if needed in both groups. All the patients were visited monthly for 9 months.

The differences of monthly checked BCVA adjusted for the BCVA at the base (month 0) were significantly higher in group B since the 4th to 8th month (p= 0.002 - 0.044 - 0.002 - 0.002 - 0.012). The differences of monthly checked central macular thickness (CMT) values adjusted for the base (month 0) was also significantly higher in both groups since the 1st to 9th month of study (all p<0.001). We disclosed a less frequent IVB injections among the participants in group B at the 4th, 6th, 7th, and 8th months (p=0.022, <0.001, 0.012, 0.038). The same trend was observed in consideration of all injections within the 9-month-period of survey between A and B groups respectively (5.83±1.95 vs. 4.05±1.09; p<0.001).

The photocoagulation of retinal nonperfused area in ischemic CRVO might amplify the advantageous therapeutic effects of IVB on BCVA as well as CMT and culminates in a dramatic diminution of IVB injection frequency.