Analysis Of Corneal Endothelial Cell And Astigmatism Changes After Cataract Phacoemulsification By Three Different Incisions

Objective To compare the corneal endothelial cell and astigmatism differences of patients after phacoemulsification surgery through traditional superior scleral tunnel incision,clear corneal incision at the superior nasal or superior temporal or phacoemulsification surgery through temporal clear corneal incision and implantation of different intraocular lenses (IOL).Methods In a randomized sample controlled clinical trial, 90 patients (132 eyes) with age-related cataract were divided into 3 groups: (Group A) traditional superior scleral tunnel incision phacoemulsification surgery, 30patients, 45eyes; (Group B) clear corneal incision at the superior nasal or superior temporal phacoemulsification surgery, 29 patients,41eyes and (Group C) temporal clear corneal incision phacoemulsification surgery,31 patients, 46eyes. IOL were implanted with three groups. Patients undergoing eyes'uncorrected visual acuity, crystal nuclear hardness, anterior chamber depth, central corneal cell density, corneal topography tests were measured pre-operatively. Ultrasound Time (UST), Cumulative Dissipated Energy (CDE) were recorded intraoperatively. The uncorrected visual acuity, central corneal endothelial cell density was calculated and corneal topography tests were performed in 1 week, 1 month, 3 month postoperatively. The data was analyzed statistically by SPSS13.0.Result (1) The difference of changes in the density of corneal endothelium was not significant among groups with different incisions before and after operation (P>0. 05). (2) The central corneal endothelial cell density in 1 week, 1 month and 3 month after operation were not significantly different with preoperative data in group A.(3) The central corneal endothelial cell density of group B and C in 1 week, 1 month and 3 month after operation were significantly different with preoperative data, but not in 1 week and 1 month; 1 week and 3 month or 1 month and 3 month.(4) The corneal endothelial cell loss was closely related to the crystal nuclear hardness.(5) The ratio of against-the-rule astigmatism increased in group A and B, decreased in group C after the phacoemulsification surgery.(6) The difference of changes in the mean corneal astigmatism was not significant between group A and C after operation (P>0.05), but significant between group A and B, group B and C (P<0.05).(7) Group B's mean corneal astigmatism in 1 week, 1 month and 3 month after operation were significantly different with preoperative data(P<0.05), but not in 1 week and 1 month; 1 week and 3 month or 1 month and 3 month(P > 0. 05). (8) There were no significant differences of mean corneal astigmatism between preoperative and postoperative data in group A and C.Conclusion The temporal clear corneal incision and traditional superior scleral tunnel incision induced the corneal endothelial cell loss was only a response in the early period of postoperation. The corneal endothelial cell loss was closely related to the crystal nuclear hardness. Two kinds of incisions didn't cause high astigmatism postoperatively. The clear corneal incision at the superior nasal or superior temporal induced more corneal endothelial cell loss and high astigmatism, although it convenient.