Corneal refraction analysis of phacoemulsification between bimanual microincision and conventional incision

Objective To compare the corneal refraction changes of bimanual microincision phacoemulsification with conventional incision phacoemulsification. Design Prospective case series. Participants 102 patients (122 eyes) performed phacoemulsification. Methods 58 patients ( 66 eyes) were in group1 (bimanual microincision phacoemulsification ) and 44 patients ( 56 eyes) in group2 (conventional corneal incision phacoemulsification). TMS-4 corneal topography was used to evaluate the corneal refraction changes at pre-operation and 1 week , 1 and 3 months post-operation. Main Outcome Measures Mean corneal curvature in the center of cornea 3 mm and 6 mm. Results At 3 months post-operation in the center of cornea 3 mm: semimeridian mean corneal curvature at 10:30 direction was -0.06±0.91 D in group1, -0.44±0.53 D in group2 (P=0.025). Meridian mean corneal curvature at 10:30 was -0.07±0.55 D in group1, -0.26±0.42 D in group2 (P=0.099). Surgically induced astigmatism (SIA) was 0.22 ±0.59 D in group1, 0.43±0.60 D in group2 (P=0.139). At 3 months post-operation in the center of cornea 6 mm: semimeridian mean corneal curvature at 10:30 direction was -0.35±0.57 D in group1, -0.68±0.61 D in group2 (P=0.022). Meridian mean corneal curvature at 10:30 was -0.32±0.71 D in group1,-0.34±0.42 D in group2 (P=0.909). SIA was 0.33±0.98 D in group1, 0.50±0.60 D in group2 (P=0.342). There were statistically significant differences between these two groups in semimeridian, meridian mean corneal curvature at 10:30 and SIA (all P0.05) at 1 week and 1 month after the operation. Conclusions Bimanual microincision phacoemulsification has lower changes of the mean corneal curvature compared with conventional incision phacoemulsification.