Effect of location of opening incision on astigmatic correction after small-incision lenticule extraction

We compared the visual and refractive outcomes between 2 different incisional sites in small incision lenticule extraction (SMILE) for low myopic astigmatism. This was a contralateral eye study. Consecutive cases that underwent bilateral SMILE surgery were included. Procedures for both eyes were identical apart from the location of opening incision. The incision was set on the temporal side for the right eye (Group 1), while a superior incision was set for the left eye (Group 2). Twenty-nine patients with a mean age of 35.0 ± 9.6 years were included. Preoperative visual and refractive parameters were comparable between the 2 groups (p > 0.250). At 3 months, the logMAR uncorrected distance visual acuity was 0.074 ± 0.090 in Group 1 and 0.084 ± 0.130 in Group 2 (p = 0.861). No difference was found in the postoperative manifest spherical equivalent (p = 0.501) and manifest cylinder (p = 0.178) between the 2 groups. The efficacy index was 0.85 ± 0.16 in Group 1 and 0.85 ± 0.20 in Group 2 (p = 0.828). Astigmatic correction was not significantly affected by the location of opening incisions using vector analysis. Our study did not find significant differences in visual and refractive outcomes with temporal or superior opening incision during SMILE surgery.