Objective To compare the safety and efficacy of a modified 23G with suturing incision and traditional 23G vitrectomy for silicone oil removal.Methods A total of 177 patients (180 eyes) who underwent silicon oil removal (the average tamponade period was 4.5 months) were enrolled in this prospective study.The patients included 112 males (113) and 65 female (67).The mean age was (43.8±10.3) years.The corrected vision,indirect ophthalmoscopy,intraocular pressure,B-ultrasound and optical coherence tomography were measured for all patients.All patients had no complete retinal detachment.The patients were randomly divided into modified 23G with suturing incision group (group A,88 eyes) and traditional 23G vitrectomy (group B,92 eyes).The differences of sex (x2 =1.596),age,corrected vision (t=0.785),intraocular pressure (t=0.352),primary disease (x2 =1.982) and lens condition (x2 =2.605)were not significant (P>0.05).The operation time,intraocular pressure,silicon oil retention,choroidal detachment,retinal redetachment and endoophthalmitis were recorded at the end of the operation.Results The difference of mean operation time was not significant between group A and B (t =1.950,P>0.05).The differences of mean visual acuity 1 day,1 week and 3 months after operation were not significant between group A and B (t=0.873,1.115,0.141; P>0.05).There was difference of mean intraocular pressure at 1 day after operation (t =2.550,P<0.05),but not at 1 week and 3 months after operation (t =1.451,1.062; P>0.05) between group A and B.There were 25 eyes (28.4%) with intraocular hypotension,8 eyes (9.1%) with choroidal detachment,5 eyes (5.7 %) with vitreous hemorrhage,9 eyes (10.2 %) with retinal redetachment,and 7 eyes (8.0%) with silicon oil retention in group A.There were 5 eyes (5.4%) with intraocular hypotension,2 eyes (2.2%) with choroidal detachment,2 eyes (2.2%) with vitreous hemorrhage,8 eyes (8.7 %) with retinal redetachment,and 1 eye (1.1 %) with silicon oil retention in group B.The differences of incidence of intraocular hypotension,choroidal detachment and silicon oil retention were significant (P<0.05).No endoophthalmitis occurred.Conclusion The safety of modified 23G with suturing incision is better than traditional 23G vitrectomy for silicone oil removal,with decreased incidence of intraocular hypotension,choroidal detachment and silicon oil retention. Key words: Vitrectomy/methods; Surgical procedures, minimally invasive/adverse effects; Silicone oils