Purpose: Surgically induced astigmatism (SIA) has become more important in nowadays refractive lens surgery. The purpose of this study was to explore factors contributing to the following phacoemulsification.
Methods: This retrospective study included 842 eyes following 2.2mm (cartridge D, n=248), 2.75mm (cartridge C, n=357; cartridge B, n=116), and 3.2mm (folding forceps, n=121) sized superior limbal incision phacoemulsification. Intraocular pressure (IOP) was measured by Topcon CT80 pneumotonometer and corneal curvatures were measured by Topcon KR 8900 auto-refractor for all eyes. Preoperative axial length (AxL) and anterior chamber depth (ACD) were measured with Zeiss IOL Master in 2.2mm (cartridge D) and 2.75mm (cartridge C) groups. Postoperative corneal curvatures and IOP were measured at 1 day, 1 week, 1 month, and 3 months following surgery. SIA was calculated using Alpin’s method. Difference in SIA between various wound sizes was explored. Correlations between preoperative astigmatism, corneal curvatures, ACD, AxL, IOP, age and SIA were analyzed for various wound sizes.
Results: Smaller SIA were found in 2.2 mm than in 2.75mm and 3.2 mm groups. The SIA and IOP stabilized earlier in 2.2 mm group than in 2.75 mm groups. In addition to wound size, higher preoperative corneal astigmatism, older age, shallower ACD contributed to larger SIA for 2.2mm+MIIID and 2.75mm+MIIC groups. However, shorter AxL and lower IOP induced larger SIA in 2.75mm group, but not in 2.2 mm group.
Conclusions: Decreasing limbal wound size and considering factors other than corneal astigmatism in predicting SIA could contribute to optimize refractive lens surgery. |