Objective Our study was performed to design a drug-sustained capsular tension ring (CTR) to evaluate its potentiality on prevention of PCO in the swine capsular bag model in vitro.Methods Following the continuous capsule curvilinear capsulorhexis ( CCCC),Phacomulsification with capsular tension ring implantation was pedormed.CTR-supported swine capsular bag models were prepared and divided into two groups,group CTR ( n =13 ) implanted with the original CTR without any modification and group CTR-PLGA-MG132 ( n =13) implanted with the CTR covered with PLGA and MG132.The CTRsupported capsular bags were cultured in vitro for up to 3 weeks.The area of lens epithelial cells (LEC) coverage over the posterior capsule surface was quantified every day under microscope.The capsules were treated for histological examination.The change of fibronectin was assessed by ELISA assay kit.Results After 2 ～ 3 days,outgrowth of LEC across the posterior capsule was observed,and the posterior capsule was totally covered by a confluent monolayer of cell after (9.06 ± 1.61 ) days in group CTR.Capsular wrinkles became increasingly apparent as time progressed.An increase in capsular thickness was also observed.In contrast,there was less LEC deposition in group CTR-PLGA-MG132.Histological examination showed LEC layers were closely arranged on the posterior capsular surface in group CTR.In group CTR-PLGA-MG132,there was comparatively looser cell arrangement.Compared with group CTR,the mean fibronectin level of posterior capsule by week 3 in group CTR-PLGA-MG132 was 25.14 μg/ml and 106.09 μg/ml respectively.Statistical analysis showed a significant difference ( P ＜ 0.01 ).Conclusions LEC migration,proliferation,and synthesis of EMT markers were inhibited in Group CTR-PLGA-MG132,compared with Group CTR.Drug-sustained capsular tension rings can effectively inhibit the migration,proliferation of LEC and the change of EMT ( epithelial-to-mesenchymal transition) in swine capsular bag models.Drug-sustained capsular tension rings might be a potential therapy to prevent the posterior capsular opacification in the future.