AIM: To evaluate the efficacy and stability by comparing acuity and diopter of small incision lenticule extraction(SMILE), femtosecond laser in situ keratomileusis(FS-LASIK)and laser in situ keratomileusis(LASIK)in treating myopia with a follow-up of 6mo.

METHODS: A retrospective study, 42 cases(84 eyes)received SMILE, 37 cases(74 eyes)received FS-LASIK and 31cases(62 eyes)undergone LASIK in our hospital during Apr.2014 to Jun.2014 were involved. The follow-up data of 6mo was analyzed. The preoperative spherical equivalent was -5.91±1.83D, -5.89±1.96D, -5.88±1.68D in SMILE, FS-LASIK and LASIK group, respectively. The differences of preoperative best corrected visual acuity(BCVA), pupil diameter(PD)and central corneal thickness(CCT)had no statistically significant between three groups. The postoperative uncorrected visual acuity(UCVA), BCVA and diopter were comparative analyzed at 1wk, 1, 3 and 6m after surgery.

RESULTS:1)No patients lost to follow-up of 1wk and 1mo. A total of 10 eyes(5 cases), 10 eyes(5 cases)and 8 eyes(4 cases)lost to follow-up of 3m in SMILE、FS-LASIK and LASIK group, respectively, and raised to 18 eyes(9 cases), 12 eyes(6 cases)and 14 eyes(7 cases)in follow-up of 6m. 2)At 1wk follow-up, the differences of UCVA between SMILE group, FS-LASIK group vs LASIK group was statistically significant respectively(t=4.098, P=0.000; t=2.493, P=0.004). 3)In LASIK group, the differences of UCVA between 1wk vs 3, 6m follow-up was statistically significant respectively(t=3.410, P=0.001; t=3.771, P=0.000), the differences of UCVA between 1m and 6m follow-up was statistically significant(t=2.283, P=0.026). 4)The differences of diopter were not statistically significant among three groups at 1wk, 1, 3 and 6mo follow-up respectively(χ²=0.119, P=0.942; χ²=1.504, P=0.471; χ²=0.949, P=0.622; χ²=0.277, P=0.871). 5)the differences of eyes with UCVA≥5.0 was statistically significant between SMILE group vs FS-LASIK group, LASIK group at 1wk follow-up(χ²=9.249, P=0.002<0.05/3; χ²=12.906, P=0.000<0.05/3), there was no significant statistical difference between FS-LASIK group and LASIK group(χ²=0.500, P=0.604). 6)there was no significant statistical difference of eyes with SE(±0.50D)at any time post operation among three groups(χ²=0.809, P=0.697; χ²=1.176, P=0.634; χ²=0.871, P=0.736; χ²=0.683, P=0.770).

CONCLUSION: All of SMILE, FS-LASIK and LASIK are effective and stable on treating myopia according to follow-up of 6mo. However, in this study, SMILE group shows more effective than FS-LASIK and LASIK at 1wk, which could enhance postoperative UCVA more rapidly.