AIM: To investigate changes in tear film stability and corneal biomechanics after femtosecond laser small incision lenticule extraction(SMILE)and femtosecond laser LASIK(F-LASIK)for one year.

METHODS:A total of 43 patients(86 eyes)with SMILE and 47 patients(94 eyes)with F-LASIK were chosen from Jun.2014 to Jul.2015, whose surgery all successfully and medical records were complete. Average tear film break-up time(aBUT), Schirmer Ⅰ test(SⅠt)and Pentacam were obtained before surgery and at 1, 6 and 12mo after surgery. The paired t-test were used to analyze the collected data.

RESULTS: There was no significant difference in age, central corneal thickness(CCT)and optometry before surgery. The mean fellow time after surgery was(14±1.92)mo. The values of aBUT and SⅠt was no significantly different in before surgery and 1mo after surgery. There was significantly different in aBUT between 2 groups in 6 and 12mo after surgery(P<0.05). The SⅠt value only show different in 6mo after surgery. After one year, the posterior elevation of the thinnest point in SMILE and F-LASIK were(4.11±2.35)μm,(4.21±2.09)μm. The data of the central point were(1.33±0.94)μm,(1.23±0.93)μm. Whatever preparation or long time after surgery, there was no significantly different in 2 groups(P>0.05).

CONCLUTION: SMILE surgeries have superiority over F-LASIK in tear film stability. There is no change in corneal biomechanics, the posterior corneal surface is stable for long- term after SMILE or F-LASIK.