Purpose:

To evaluate the efficacy of 3.0 mm vs. 4.1 mm clear corneal incisions on the steep axis in phacoemulsification surgery to correct pre-existing astigmatism.

Material and Method:

Twenty-one eyes of 21 patients who had phacoemulsification surgery with 3.0 mm clear corneal incision and 22 eyes of 22 patients with 4.1 mm clear corneal incision were included in the study. After routine ophthalmic examination, all patients had topographic evaluations both preoperatively and on postoperative 7th, 30th and 90th days. Surgically induced astigmatism was calculated using Naeser’s polar value method on postoperative 7th, 30th and 90th days.

Results:

The mean age was 64.33 years in Group 1 and 63 years in Group 2 (p>0.05). The mean preoperative astigmatism decreased from 0.69 D to 0.58 D and from 1.66 D to 1.49 D on postoperative day 90 in Group 1 and Group 2, respectively (p<0.01). Surgically induced astigmatism values according to Naeser’s polar value method on postoperative 7th, 30th and 90th days were -0.27 D, -0.26 D, -0.18 D in Group 1, and -0.89 D, -0.52 D, -0.26 D in Group 2, respectively. There was no statistically significant difference between the groups according to these values on postoperative day 90 (p>0.05). The torque effect of the incision on posoperative 7th, 30th and 90th days were -0.031, -0.036, 0.018 in Group 1 and -0.004, 0.067, 0.056 in Group 2, respectively. According to torque effect, there was no statistically significant difference between the two groups (p>0.05).

Discussion:

There is no significant difference between 3.0 mm and 4.1 mm incisions in terms of surgically induced astigmatism on postoperative day 90. Both incisions caused statistically insignificant flattening effect on the surgical steep meridian, but greater effect was observed in patients with 4.1 mm corneal incisions.

Keywords: Surgically induced astigmatism, phacoemulsification, corneal incision