Effect of different clear-corneal incisions on high-order corneal aberration in phacoemulsification cataract surgery

Objective To investigate the effect of different clear-Corneal incisions on the high-order wavefront aberrations in phacoemulsification cataract surgery.Methods Ninety-eight eyes of 98 patients were randomly selected and divided into 3 groups according to the steepest corneal meridian.Group A:the incision was placed at the 180-degree,group B:135-degree,group C:90-degree.Phacoemulsification cataract surgeries were performed through 2.8mm clear-corneal incision.The 3-6 order aberrations were measured by Pentacam HD.All the changes in Corneal aberration difference before and after operation between the absolute value were statistically analyzed by one-way ANOVA.Results The x-axes direction of corneal coma Z (3,1) and spherical aberrations Z (4,0) became smaller at group A than those in group B and group C; however the y-axes direction of Second-order clover Z (5,-3) changed most obviously in all three groups.All of the changes had significant difference.The y-axes direction of Second-order astigmatism Z (4,2),the x-axes direction of Second-order coma Z (5,1),y-axes direction of Second-order four-leaf clovers Z (6,-4) and x-axes direction of Second-order four-leaf clovers Z (6,4) changed most significantly in group B.Conclusions 180-degree corneal incision is the most stable incision considering surgery-induced high-order aberration especially for spherical aberrations Z (4,0). Key words: Wavefront aberrations;  Incision;  Cornea;  Age-related Cataract