AIM: To analyze the changes of the dominant eye in myopic patients after small incision lenticule extraction(SMILE)and its effect on visual quality.

METHODS: Prospective clinical study. A total of 140 patients(280 eyes)who underwent SMILE operation to correct myopia in the First Affiliated Hospital of Xinjiang Medical University from June to December 2022 were selected. They were divided into dominant eye transformation group(46 cases, 92 eyes)and non-transformation group(94 cases, 188 eyes)according to whether the dominant eye transformation occurred during the follow-up in postoperative 3 mo. The uncorrected visual acuity(UCVA)of the two groups was evaluated, the subjective visual quality was evaluated by the quality of life impact of refractive correction(QIRC)scale, and the objective visual quality was evaluated by measuring the high-order aberrations of the whole eye before and at 1 and 3 mo after surgery.

RESULTS: Before SMILE, the right type of dominant eye was 105 cases, left-type was 35 cases. There were 46 cases had change at 1 mo postoperatively, and there was no new change at 3 mo after operation than 1 mo after operation. There was no significant difference in UCVA and QIRC scale score between the two groups preoperatively and at 1 and 3 mo postoperatively(P>0.05). Comparison of the dominant eye between the two groups: the total higher-order aberrations and spherical aberrations at 3 mo postoperatively were significantly higher than those in the non-transformed group(P=0.030, 0.046); Comparison of the non-dominant eye between the two groups: trefoil in the transformed group at 1 mo postoperatively was significantly higher than that in the non-transformed group(P=0.008). The binocular difference of trefoil in the transition group was significantly higher than that in the non-transition group at 1 mo after surgery(P=0.022), with no differences in the rest parameters.

CONCLUSION: Some patients may experience a change in the dominant eye after SMILE surgery, with no significant impact on subjective visual quality. The decrease of objective visual quality in the early postoperative period may be an associated factor in the dominant eye transformation.