Astigmatic changes after cataract surgery with different position of 6 mm sutureless incision

Objective To study the effect of the different position of near limbus incision on the changes of preoperative and postoperative astigmatism after phacoemulsification and intraocular lens implantation and evaluate their clinical results.Methods Seventy eyes of sixty seven patients were divided into two groups randomly according to the incision location;Group A comprised 34 eyes which had surgery using superior approach,Group B comprised 36 eyes which had surgery using the superolateral apporach.All patients underwent phacoemulsification and intraocular lens implantation through 0.5mm posterior limbus,two-stepped tunnel incision which has tunnel length of 1.75mm with diamond knife.Keratometry measurements were obtained preoperatively,at postoperative 1 week,1 month,3 months and 6 months respectively by Nikon Keratometre We compared the mean surgically induced astigmatism(SIA),mean postoperative uncorrected visual acuity between the two groups up to 6 months postoperatively,SIAs were analyzed by “Holladay vector method”.Results Mean uncorrected visual acuity in group B is significantly better than that in group A at 1 week postoperatively(P0.05),but there are no significant differences between the two groups at 1,3 and 6 months postoperatively(P0.05).Eyes in the group B displayed significantly less mean SIA and mean corneal astigmatism than group A at 1 week 1 month and 3 months postoperatively especially against-the-rule(ATR)astigmatism preoperatively(P0.05),there are no significant differences between the two groups at 6 month postoperatively(P0.05).Astigmatic axis in group A is whole ATR astigmatism postoperatively.Astigmatic axis of large number of patients in group B are with-the-rule(WTR)astigmatism postoperatively.Conclusions The superolateral near limbus incision would effectively minimize the wound-stretching forces and result in earlier lesser degree of corneal astigmatism and better uncorrected visual acuity postoperatively.6mm sutureless near limbus tunnel incision for phacoemulsification with intraocular lens implantation is safety and credible.