Human lens epithelial cell apoptosis and epithelial to mesenchymal transition in femtosecond laser-assisted cataract surgery

AIM： To evaluate human lens epithelium cell apoptosis and epithelial to mesenchymal transition （EMT） induced by femtosecond laser in femtosecond laser assisted cataract surgery （FLACS）. METHODS： Sixty cataract patients with N2 to N3 stage according to the LOCS III were enrolled in this study and divided into three groups randomly： FLACSl group （cataract surgery by FLACS with LenSx）, FLACS2 group （cataract surgery by FLACS with LensAR） and manual group （cataract surgery by phacoemulsification）. Patients in two FLACS groups performed anterior capsulotomy by LenSx or LensAR laser system. Patients in the manual group were performed continuous curvilinear capsulorrhexis （CCC） manually. The anterior capsules were fixed right after moved out of eye. Hematoxylin-eosine staining, immunofluorescence staining and real-time PCR were performed in order to observe human lens epithelium cells changes after cataract surgery. RESULTS： The capsule cutting edge was shown irregularity and roughness in two FLACS groups and smooth edge in manual capsulotomy by pathologic staining. Irregularities of the cell configuration with partly swollen and destroyed nuclei were observed in two FLACS groups. Femtosecond laser could induce a significantly higher cell apoptosis in human lens epithelium cell than manually performed CCC （P〈0.05）. Lens epithelium cells apoptosis were correlated with femtosecond laser duration according to Pearson correlation analysis. Decreased N-cadherin expression, alpha-SMA and FSP-1 level in two FLACS groups showed the inhibition of cell EMT. CONCLUSION： Femtosecond laser may affect the apoptosis and EMT of lens epithelium cells which are under the peeled central lens capsule.

Safety of femtosecond laser-assisted cataract surgery versus conventional phacoemulsification for cataract:A meta-analysis and systematic review

Purpose:To compare the complications of femtosecond laser-assisted cataract surgery(FLACS)with those of conventional phacoemulsification surgery(CPS)for age-related cataracts.Methods:PubMed,Cochrane Library,and EMBASE were systematically searched for studies comparing FLACS and CPS.Outcomes were operative complications,including the intraoperative capsule tear,postoperative corneal edema,macular edema,uncontrolled IOP,etc.The effect measures were weighted with odds ratios with 95%CIs.Results:Nineteen RCTs and 18 cohort studies,including 24,806 eyes(11,375 of the FLACS group and 13,431 of the CPS group),were identified.There were no significant differences between the two groups in anterior capsule tear,corneal edema,macular edema,uncontrolled IOP,vitreous loss,posterior vitreous detachment,etc.Posterior capsule tear rate showed a significantly lower in RCT subgroups(P=0.04)and without differences in total(P=0.63).Significant differences were observed in the incidence of descemet membrane tear/trauma(P=0.02)and IFIS/iris trauma(P=0.04.Additionally,The FLACS specific complications showed a significantly higher rate of miosis(P=0.0001),corneal epithelial defect(P=0.001),corneal haze(P=0.002),and subconjunctival hemorrhage(P=0.01).Conclusions:FLACS maintains the same safety compared with CPS in terms of all intraoperative and postoperative complications.Although FLACS did show a statistically significant difference for several FLACS specific complications,it would not influence the visual outcome and heal itself.