Materials and Methods: We evaluated 86 patients who had undergone cataract surgery. All eyes were measured for both anterior and posterior corneal surfaces with the Scheimpflug tomography system preoperatively and one month after surgery. In Group 1, the surgery began with a side incision while in Group 2 the main incision was done first. Comparisons between groups were analyzed via student?s t-test and Mann-Whitney U-test. Pearson?s correlation was performed to analyze the relationship between preoperative astigmatism and SIA. P-values< 0.05 were considered statistically significant.

Results: Surgically induced anterior astigmatism (SIA-A) in Group 1 and Group 2 was 0.76 ± 0.43 D and 0.67 ± 0.38 D (p=0.274), surgically induced posterior astigmatism (SIA-P) was 0.27 ± 0.19 D and 0.22 ± 0.15 D (p=0.168), respectively. SIA-A of 1.0 D or greater was found in 24.4% of eyes in Group 1 and 15.6% of eyes in Group 2. SIA-P of 0.5 D or greater was found in 14.6% of eyes in Group 1 and 12.2% of eyes in Group 2. There was a statistically significant increase in anterior astigmatism (p=0.002 in Group 1, p=0.005 in Group 2) but not in posterior astigmatism (p=0.536 in Group 1, p= 0.219 in Group 2).

Conclusion: Making the main incision first caused less SIA on both anterior and posterior surfaces; however, the difference was not significant. Keywords : Cataract surgery, Incision sequence, Surgery induced astigmatism, Corneal tomography