Prediction Of Retreatment Of Polypoidal Choroidal Vasculopathy By Changes Of CVD Height Under The Central Fossa

Objective:To investigate whether the changes of choroidal vascular diameter and choroidal thickness in the central fovea can predict the retreatment of polypoid choroidal vascular disease(PCV).Methods:Retrospective case-control study.Patients with PCV who received 3+PRN anti-vascular endothelial growth factor(VEGF)therapy(Conbercept)were followed up for more than 6 months.The systemic condition at baseline was counted.The changes of BCVA,intraocular pressure,OCT parameters at 1 day,1 month,2 months,3 months and6 months after injection were recorded.The times of injection,dry macula and recurrence were counted at the end of follow-up period.OCT recorded the following parameters:foveal retinal thickness(CRT),choroidal vascular diameter(CVD),choroidal thickness CT,retinal pigment epithelium effusion,subretinal effusion(SRF).The indication of retreatment is recurrence of intraretinal or subretinal effusion or new hemorrhage.The changes of CVD and choroidal thickness between dry macular follow-up"D",previous follow-up"D-1"and subsequent recurrent"R"were analyzed by software based on optical coherence tomography.The choroidal thickness including macular sub-foveal choroidal thickness(SFCT),central fovea nasal side 1500um choroidal thickness(CT)and central fovea nasal side 1500um choroidal thickness.T-test and multivariate regression analysis were performed to determine the relationship between the changes of CVD and choroidal parameters and the need for retreatment in the follow-up of“R”.Results:A total of 52 patients(54 eyes)(mean age 66±12 years)with qualified PCV were included in ophthalmology department of our hospital from March 2017 to February2020.At baseline,the average CRT was 411.0±193.2)um,choroidal parameters were SFCT263.2±61.4um,CT(temporal side)254.±68.0um,CT(nasal side)243.2±27.4um,CVD 152.9±21.5um,PED0.10±0.12um~2,SRF0.24±0.33 um~2.32 eyes(59.2%)were included in the effusion regression group at the average third follow-up,and the other 22eyes(40.7%)were included in the non-regression group.In these two groups,the prognosis of the non-regression group was worse,and the prognosis was related to the baseline CVD,the course of disease and the occurrence of effusion regression.Eighteen patients(56.3%)had exudation and recurrence during the follow-up period,and the average time point of recurrence was 4 times of follow-up(that is,the next visit after the disappearance of effusion),which was included in the recurrence group for retreatment in R times of follow-up,and the rest of the patients without recurrence were included in the control group.BCVA,CRT,CVD and choroid thickness were significantly improved compared with the initial value after 6 months of treatment.In the effusion regression group,the CVD and choroidal thickness decreased continuously from baseline to D follow-up,but there was no significant change from D-1 to D follow-up.At D time point,the CVD and choroidal thickness in the effusion regression group were significantly lower than those in the non-regression group(P<0.05),indicating that the occurrence of effusion regression was significantly related to the changes of CVD and choroid thickness.In the control group(non-recurrent group),the CVD and choroidal thickness decreased continuously from the baseline to the first follow-up(P<0.05),and there was no significant change in one month before the occurrence of offusion regression.In recurrent group,choroidal thickness increased significantly within one month before recurrent R,and CVD increased significantly before this month.There were significant differences in CVD and choroidal thickness between recurrent group and non-recurrent group(P<0.05).From D to R,CVD and the thickness of choroid were related to the increase of the probability of retreatment of R,with OR values of 4.5(95%CI0.9-32.1;P=0.01)and SFCT:OR6.5(95%CI1.8-32.1;P=0.04),CT(temporal)OR 1.7(95%CI0.6–5.9;P=0.03),CT(nasal side)OR 1.7(95%CI0.3-11.5;P=0.05),respectively.Conclusion:PCV patients treated with anti-VEGF the increase in CVD and choroidal thickness at visit,even if dry macula has been achieved,is related to retreatment at the next follow-up.Current retreatment criteria for intraretinal or subretinal effusion or hemorrhage may be extended to include changes in CVD and choroidal thickness.Further research is needed to determine whether the use of CVD and choroidal parameters in treatment decisions can reduce recurrence.