These findings highlight distinct inflammatory features of recurrent RVO and provide a basis for future studies investigating disease progression and treatment resistance.<h4>Trial registration</h4>UMIN000020718 https://center6.umin.ac.jp/cgi-open-bin/icdr_e/ctr_his_list.cgi?recptno=R000023907 .<h4>Key messages</h4>WHAT IS KNOWN: While anti- endothelial growth factor (VEGF) therapy is effective for treating cystic macular oedema (CME) secondary to retinal vein occlusion (RVO), the condition is not confined to the acute phase. This evidence concerns the gene VEGFA and retinal vein occlusion.