The clinical analysis of corneal astigmatism changes after cataract surgery with different locations of clear corneal incision / 中国医师进修杂志

ABSTRACT

Objective To evaluate the corneal astigmatism changes after phacoemulsification performed using clear corneal incision with different locations.Methods Seventy-two eyes of 72 patients having phacoemulsification and implantation of foldable intraocular lens through a clear corneal incision were chosen.Patients were divided into two groups by table of random digitgroup A (incision at 1100),group B (incision at the steepest corneal meridian).The change of corneal astigmatism was compared between group A and B postoperatively.Surgically-induced astigmatism (SIA) was calculated by vector analyses using the HoHaday-Cravy-Koch method.Results Preoperative corneal astigmatism between group A and group B had no significant difference [(0.96 ± 0.52) D vs.(0.94 ± 0.56) D,P ＞ 0.05].One and three months after operation,the corneal astigmatism in group A were significantly higher than those in group B [(1.15 ± 0.32)D vs.(0.82 ± 0.43) D,(0.85 ± 0.38) D vs.(0.63 ± 0.40) D,P＜ 0.05].The SIA in group A was significantly higher than that in group B 1 month after operation [(0.85 ± 0.37) D vs.(0.75 ± 0.54) D,P ＜ 0.05],there was no significant difference between group A and group B 3 months after operation [(0.60 ±0.35) D vs.(0.58 ±0.30) D,P ＞0.05].Conclusions Corneal astigmatism is prｅsent in most cataract surgery candidates.Cataract surgery using steepest corneal meridian incision induces significantly less SIA,and correct corneal astigmatism already present preoperatively.