Effect Of Anti-VEGF Therapy On Retinal Non-perfusion Area Of Diabetic Macular Edema

ObjectiveTo investigate the changes of nonperfusion area(NPA)of retina after intravitreal injection of Aflibercept in the treatment of diabetic macular edema(DME)and its correlation with the changes of retinal function.MethodsThis study is a retrospective analysis.A sample of 29 eyes of 21 cases with severe nonproliferative diabetic retinopathy(NPDR)with macular edema diagnosed in the First Affiliated Hospital of Nanchang University ophthalmology clinic from January2020 to June 2022 and with a non-perfusion area on the retina as shown by ultrawide field fluorescein angiography(UWF-FA)while treated with intravitreal injection of Aflibercept(0.05 ml,40 mg/ml)for 6 months according to the 3+PRN protocol was selected for inclusion in the study.Patients were divided into three groups: increased ischemia index(group A),unchanged ischemia index(group B),and decreased ischemia index(group C),according to the changes of retinal ischemia index(the ratio of the sum of the non-perfusion area of the retina to the total retinal area)shown by UWF-FA after 6 months of treatment with the anti-vascular endothelial growth factor(VEGF)drug Aflibercept compared with baseline.Group A had 7 eyes,group B had 5eyes,and Group C had 17 eyes.Blood glucose,blood pressure,blood lipids,intraocular pressure,best corrected visual acuity(BCVA),central macular thickness(CMT),glycosylated hemoglobin,times of injection,ISI at baseline and 6 months after treatment were recorded during follow-up 6 months.Statistical analysis was conducted on gender,age,diabetes course,axis of the eyes,glycosylated hemoglobin,BCVA,intraocular pressure,CMT,ISI and BCVA,intraocular pressure,CMT and other data of patients between the three groups before treatment.At the same time,statistical analysis was conducted on the changes of the non-irrigation area of the retina with severe NPDR and macular edema after 6 months of intravitreal injection of Aflibercept in the three groups and the data of BCVA and CMT after treatment.In addition,Image J image processing software was used to analyze whether reperfusion occurred in the non-perfusion area of retina after 6 months of anti-VEGF treatment.Results1.The differences in gender,age,eye category,eye axis,glycated hemoglobin,intraocular pressure,BCVA,CMT,and ISI between groups A,B,and C were not statistically significant(P>0.05).In addition,the differences in the duration of diabetes mellitus between patients in groups A and C before treatment were statistically significant(P<0.05),but the differences in the duration of diabetes mellitus between groups B and C and A and B were not statistically significant(P>0.05).2.There were no statistically significant differences in BCVA,CMT and the number of drug injections between groups A,B and C at 3 months and 6 months after treatment(P>0.05).BCVA and CMT at 3 months and 6 months after treatment in groups A,B and C showed different degrees of improvement compared to BCVA and CMT before treatment,and the differences were statistically significant(P<0.05).3.The mean ISI of all patients in this study was 5.17±1.12% before treatment and improved to 5.12±1.44% 6 months after treatment,but the difference was not statistically significant(t=0.45,P=0.66).4.Image J processing showed local reperfusion in 21 of the 29 eyes in 21 cases,and no reperfusion was found in 8 eyes;there was a negative correlation between the duration of diabetes and reperfusion(r=-0.48,P<0.01),but no correlation between gender,age,eye type,eye axis,glycated hemoglobin,pretreatment BCVA,IOP,CMT,NPA,ISI,and number of drug injections and reperfusion significant correlation was found.Conclusions1.The global retinal ischemia index of patients with severe NPDR and macular edema treated by intravitreal injection of Aflibercept decreased slightly after 6 months,suggesting that retinal ischemia was improved in some patients.2.Changes in retinal ischemic status had no effect on the improvement of retinal functional parameters BCVA and retinal structural parameters CMT during the 6-month follow-up period after vitreous chamber injection of Aflibercept.3.Six months of treatment with intravitreal injection of Aflibercept did not affect the occurrence of local reperfusion in the nonperfused areas of the retina in eyes with severe NPDR combined with macular edema,but the course of diabetes may affect the occurrence of reperfusion.4.UWF-FA can be used as an important imaging test to evaluate retinal ischemia status and quantitatively analyze the retinal non-perfusion area.