Effect Of Anti-VEGF Therapy On Optic Disc Microcirculation In Patients With Macular Edema Secondary To Branch Retinal Vein Occlusion Based On OCTA

Objective:To observe the effect of anti-vascular endothelial growth factor(VEGF)therapy on radial capillary density(radial peripapillary capillary vessel density,RPCVD)and retinal nerve fiber layer(retinal nerve fibre layer,RNFL)thickness in optic disc of patients with monocular branch retinal vein occlusion(branch retinal vein occlusion,BRVO)and secondary macular edema(macularedema,ME).Methods:Twenty-four patients with monocular BRVO-ME diagnosed in the Department of Ophthalmology of the first affiliated Hospital of Gannan Medical College from January 2021 to December 2021 were treated with intravitreal injection of anti-VEGF drugs.Optical coherence tomography angiography(OCTA)was used to quantitatively measure the thickness of RPCVD and RNFL in the optic disc before and after anti-VEGF treatment,and to evaluate the changes ofbothafter anti-VEGF treatment.Results:1.the average BCVA(log MAR)in BRVO group was(0.82±0.48)beforetreatment,(0.49±0.34)after the first treatment and(0.22 ± 0.22)after the third treatment;After the first treatment,after the third treatment and after the first treatment,the BCVAwas significantly higher than that before thetreatment,andthedifferences were statistically significant(all P<0.05).2.The CMT(μm)of BRVO group before treatment,after the first treatment and after the third treatment were(572.50±166.70)、(338.50 ±126.88)and(234.21±38.55),respectively.After the first treatment,after the third treatment and before treatment,there was a statistically significant difference in BCVA between the third treatment and after the first treatment,and the visualacuity was significantly improved(all P<0.05).3.In BRVO group,full image RPCVD(48.65±4.33)%,intraoptic disc RPCVD(49.01±4.81)%,perioptic disc RPCVD(49.46±4.52)%,supranasal RPCVD(49.58±3.91)%,subnasal RPCVD(49.08±3.86)%,inferior temporal RPCVD(49.12±5.14)%,inferior temporal RPCVD(54.42±5.37)%,all higher than those before treatment(45.88±4.29)%,intradisc RPCVD(46.27±4.69)%,respectively.The percentage of RPCVD around optic disc,nasal RPCVD,subnasal RPCVD,inferior temporal RPCVD and inferior temporal RPCVD were(46.24±3.98)%,(46.00±4.03)%,(45.62±3.83)%,(45.46±5.18)% and(50.96±5.30)%,respectively.In BRVO group,the percentage of RPCVD in optic disc after three treatments was(49.01±4.81)%,which was higher than that of RPCVD(46.27±4.69)% after the first treatment.There was no significant difference in RPCVD between before and after the first treatment(all P<0.05).4.In BRVO group,the thickness of RNFL after 3 times treatment(121.50±14.25)μm was lower than that before treatment(132.04±16.86)μm,and the thickness of RNFLafter 3 times treatment(121.50±14.25)μm was significantly lower than that of RNFL after the first treatment(129.08±17.00)μm.5.There was no significant difference in the thickness of RPCVD and RNFL before and after treatment in thefelloweyegroup.6.There were significant differences in RPCVD between 6.BRVO group and fellow eye group before treatment,after the first treatment and after the third treatment.(all P<0.05).The difference of RNFL thickness between eyes before and after the first treatment was statistically significant(both P<0.05).There was no significant difference in RNFLthickness between eyes afterthree treatments.Conclusion:OCTA provides quantitative information of optic disc blood vessels,and RPCVD can be used as a useful parameter to evaluate the perfusion state of BRVO optic disc.After receiving anti-VEGF treatment,the blood flow density in the optic disc area of BRVO patients increased,suggesting that anti-VEGF drugs may improve the optic disc microcirculation,and RPCVD can be used as a useful parameter to evaluate the perfusion state of BRVO optic disc.Before treatment,the RNFL edema thickened,but after anti-VEGF treatment,the RNFL thickness decreased,whichwas thought tobe related toedema regression.