One-year Outcome And Prognostic Factor Of Intravitreal Conbercept For The Treatment Of Choroidal Neovascularization Secondary To Pathologic Myopia

Purose: To evaluate the outcome and prognostic factor of intravitreal conbercept(IVC)for the treatment of choroidal neovascularization secondary to pathologic myopia.Methods: Forty-one patients(46 eyes)with choroidal neovascularization secondary to pathologic myopia participated in this interventional retrospective study from May 2017 to December 2019.The affected eyes received one initial intravitreal injection of conbercept followed by re-treatments based on increase of central foveal thickness(CFT)or new lesions of choroidal neovascularization(1+PRN).At baseline,the patients’ best-corrected visual acuity(BCVA),spherical equivalent(SE)and axial length(AL)were collected.Clinical evaluations included best-corrected visual acuity(BCVA),fundus photography,and optical coherence tomography(OCT)at each scheduled visit at baseline,1,3,6 and 12 months after the initial intravitreal injection.CFT,ellipsoid zone(EZ)and external limiting membrane(ELM)were observed on OCT.Primary outcomes include BCVA,CFT and the number of injections.Results: The mean log MAR BCVA was significantly improved from a baseline value of0.71±0.28 to 0.52±0.32(p<0.001,n=46)at 1 month,0.75±0.35 to 0.47±0.31(p<0.001,n=37)at 3 months,0.71±0.37 to 0.39±0.31(p<0.001,n=30)at 6 months and 0.69±0.30 to 0.42±0.36(p=0.001,n=22)at 12 months after the initial IVC,respectively.The mean CFT was significantly declined to 277±146μm(p<0.001,n=46)at 1 month,273±135μm(p<0.001,n=37)at 3 months,256±146μm(p=0.007,n=30)at 6 months and244±110μm(p=0.05,n=22)at 12 months after the initial IVC,respectively,from a baseline value of 378±248μm,378±248μm,413.9±285.7μm,358.9±231μm,331.2±231.2μm.There were weak negative correlations between axial length and the BCVA improvement at month 1,3,6 and 12(r=-0.366,p=0.022,n=46;r=-0.399,p=0.032,n=37;r=-0.464,p=0.034,n=30;r=0.429,p=0.046,n=22,respectively).There were positive correlations between the baseline BCVA and the BCVA at month 1,3,6and 12(r=0.75,p<0.001,n=46;r=0.75,p<0.001,n=37;r=0.803,p<0.001,n=30;r=0.773,p<0.001,n=22;respectively).There were weak positive correlations between the baseline BCVA and the BCVA improvement at month 1 and 3(r=0.441,p=0.004,n=46;r=0.479,p=0.007,n=37;respectively),moderate positive correlation at month 6(r=0.563,p=0.008,n=30),no correlation at month 12(r=0.129,p=0.622,n=22).There was no correlation between the baseline CFT and the BCVA improvement at month 1,3and 6(r=0.061,p=0.703,n=46;r=0.196,p=0.299,n=37;r=0.43,p=0.052,n=30;respectively),and moderate positive correlation at month 12(r=0.608,p=0.01,n=22).The mean number of injections was 1.80±1.19(n=22)in the affected eyes,there were negative correlations between the number of injections and the BCVA improvement at month 1 and 3(r=-0.377,p=0.014;r=-0.362,p=0.049;respectively),and there was no correlation at month 6 and 12(r=-0.262,p=0.251;r=-0.461,p=0.063,respectively).The EZ was intact in 6(13%)eyes,and disrupted in 40(87%)eyes.There was significant difference between the affected eyes with intact EZ and disrupted EZ for the BCVA improvement at month 12(-0.47±0.21 vs-0.16±0.20,p=0.03,n=22).The ELM was intact in 10(21.7%)eyes,and disrupted in 36(78.3%)eyes.There was no significant difference between the affected eyes with intact ELM and disrupted ELM for the BCVA improvement at month 1,3,6 and 12(0.30±0.23 vs 0.23±0.24,p=0.385,n=46;0.37±0.27 vs 0.27±0.23,p=0.368,n=37;0.43±0.31 vs 0.30±0.20,p=0.308,n=30;0.35±0.29 vs 0.18±0.20,p=0.189,n=22;respectively).Conclusion: Conbercept was effective to improve BCVA and decrease CFT in the treatment of choroidal neovascularization secondary to pathologic myopia.The integrity of EZ may be the prognostic factor of better BCVA improvement 12 months after the treatment.