AIM: To compare the efficacy of intravitreal injection of ranibizumab plus low power 532 laser versus 532 laser alone for treating retinal vein occlusion(RVO)with macular edema complication.

METHODS: Retrospective study of 48 patients diagnosed RVO complicated with macular edema from June 2017 to March 2018. Group A of 31 eyes(31 patients)were treated with intravitreal injection of ranibizumab plus low power 532 laser(the power is about 2/3 of the power of group B, about 100-130mw), and group B of 17 eyes(17 patients)were treated with 532 laser(the power is 150-200mw)alone. The best corrected visual acuity(BCVA), foveal retinal thickness(CMT), FFA and fundus were observed both before and after treatment at timepoint of 1mo, 2mo and 3mo between the two groups.

RESULTS: In group A, BCVA was 0.84±0.02, 0.49±0.04, 0.29±0.04, 0.26±0.04 before and the 1, 2, 3mo after treatment. In group B, BCVA was 0.85±0.04, 0.58±0.01, 0.53±0.01, 0.53±0.02. The CMT value of group A before and after treatment was 527.5±17.59, 371±17.36, 298.5±32.87, 257.75±17.30μm, respectively. Group B was 535±16.36, 425±24.44, 420.25±17.70, 427.75±17.89μm. Intra-group comparison show statistical differences, group A had lower BCVA and CMT value than group B at the same time point(P<0.05). Inter-group comparison with pre-treatment, there was significant difference in BCVA between 1mo, 2mo and 3mo after treatment(P<0.05). The CMT and BCVA value from group A are the lowest.

CONCLUSION: Both methods are effective in treating RVO with macular edema, improving vision, alleviating ME, and effectively controlling the disease.However, combined treatment can significantly reduce macular edema, improve vision, and be more stable than laser treatment alone.