Abstract:AIM: To evaluate the changes of early visual quality of patients with high myopia after small incision lenticule extraction(SMILE)and femtosecond assisted laser in situ keratomileusis(FS-LASIK)by the double-pass optical quality analysis system Ⅱ(OQAS Ⅱ)and Pentacam corneal topography.METHODS: A prospective non-randomized controlled study was conducted among 148 eyes of 74 patients with high myopia. These patients were treated by the same surgeon in our hospital from March 2020 to September 2020. According to their wishes, 86 eyes with 43 patients were treated with SMILE and 62 eyes with 31 patients were treated with FS-LASIK. The uncorrected visual acuity(UCVA), modulation transfer function cut off frequency(MTF cut off), Strehl ratio(SR), objective scattering index(OSI), predicted visual acuity values(VA 100%, VA 20%, VA 9%), high-order aberration(HOA), horizontal aberration(Z 13), vertical coma(Z -13)and spherical aberration(Z 04)preoperatively, 1 and 7d postoperatively were collected and analyzed.RESULTS:There was no statistical significance in preoperative age, spherical equivalent(SE), UCVA, MTF cut off, SR, OSI, VA 100%, VA 20%, VA 9%, HOA, Z 13, Z -13 and Z 04(P>0.05). The OSI of the SMILE group was higher than the FS-LASIK group at postoperative 1d(2.3±2.1 vs 1.8±1.1). The difference in OSI between the two groups was not statistically significant at postoperative 7d(1.2±0.7 vs 1.3±0.7). The HOA and Z04 in the FS-LASIK group were higher than the SMILE group at postoperative 1d and 7d(P<0.001). The UCVA, Z 13, Z -13, MTF cut off, SR, VA 100%, VA 20%, and VA 9% between the two groups were no statistical significance at postoperative 1d and 7d(P>0.05).CONCLUSION:FS-LASIK is easier to introduce corneal high-order aberration and spherical aberration in the early postoperative period, while SMILE with 2mm incision only introduces higher scatter at postoperative 1d. Therefore, SMILE can obtain better visual quality than FS-LASIK in the early postoperative period among patients with high myopia after corneal refractive surgery.