Short-Term Impact of Different Corneal Incision Positions on Postoperative Astigmatism and Visual Quality After SMILE Surgery.

Abstract

This study aimed to evaluate the short-term impact of different incision positions on astigmatism and visual quality after small incision lenticule extraction (SMILE) surgery. This prospective study enrolled patients who decided to have SMILE to correct myopia. Patients were randomly allocated into three groups of different incision positions (groupA, B, and C with incision position at 90°, 120°, and 150° respectively). Preoperative and postoperative visual acuity, spherical equivalent, and high-order aberrations (HOAs) were measured and compared among groups. Astigmatism was analyzed with the ASSORT Group Analysis Calculator based on the Alpins method. A total of 148 eyes were included for analysis (48 eyes in groupA, 50 eyes in groupB, and 50 eyes in groupC). At 1month postoperatively, the mean uncorrected distance visual acuity (UDVA) logMAR in groupA, B, and C was - 0.03, - 0.03, and - 0.04, respectively. The mean corrected distance visual acuity (CDVA) logMAR in groupA, B, and C was - 0.03, - 0.04, and - 0.04, respectively (P > 0.05). The mean postoperative spherical equivalent (SE) values were - 0.01 ± 0.38, - 0.07 ± 0.39, and - 0.16 ± 0.49 (D) in groupA, B, and C, respectively (P > 0.05). There was no statistically significant difference in preoperative and postoperative magnitude of astigmatism among different groups (P > 0.05). Significant differences were found in the distribution of astigmatism axis among the three groups at 1day (P = 0.02) and 1week (P = 0.02) postoperatively. However, such differences were no longer significant at 1month after surgery (P > 0.05). No significant differences were found in HOAs among different groups 1month after surgery (P > 0.05). Different incision positions have no effect on postoperative astigmatism and visual quality 1month after SMILE surgery, though differences were found in the distribution of the astigmatism axis within 1week after the surgery.