AIM:To investigate the effects of laser in situ keratomileusis(LASIK)on ocular surface by femtosecond laser or mechanical microkeratome for creating corneal flap, and to study the effect of different corneal flap method on ocular surface after operation.

METHODS: This study included 218 cases(436 eyes)myopia patients from January 2016 to January 2017 in our hospital for refractive surgery, their medical records were retrospectively analyzed. They all underwent LASIK surgery treatment and complained of different degree of dry eye postoperatively, foreign body sensation and discomfort. Mechanical microkeratome was used in 61 cases(122 eyes)of patients and they were as control group, with femtosecond laser, 157 cases(314 eyes)were set as observation group. We compared dry eye symptom scores, corneal fluorescein staining(FL)score, break-up time(BUT)and basic tear secretion test(SⅠt)between the two groups preoperatively and postoperatively 1wk, 1, and 3mo.

RESULTS: Before surgery, dry eye symptoms scoring of two groups had no statistically significant difference(P>0.05); the scores of the two groups were significantly different before and after surgery(P<0.05); postoperatively 1wk, dry eye symptoms score of control group was greater than that of the observation group with significant difference(P<0.05), the sores at 1 and 3mo after surgery were not different between the two groups(P>0.05). There was no significant differenc on the preoperative BUT between the two groups(P>0.05). BUT before and after surgery was significantly different of both groups(P<0.05). BUT of control group was significantly lower than that of observation group postoperatively(P<0.05). Before surgery, FL score of two groups had no statistically significant difference(P>0.05); the scores of the two groups were significantly different before and after surgery(P<0.05); postoperatively 1wk and 1mo, FL score of control group was greater than that of the observation group with significant difference(P<0.05), the sores at 3mo after surgery were not different between the two groups(P>0.05). Before surgery, SⅠt of two groups had no statistically significant difference(P>0.05); the scores of the two groups were significantly different before and after surgery(P<0.05); postoperatively 1wk and 1mo, SⅠt of control group was lower than that of the observation group with significant difference(P<0.05); SⅠt at 3mo after surgery were not different between the two groups(P>0.05). Two groups of patients had no serious postoperative complications occurred.

CONCLUSION: Compared with the mechanical microkeratome for creating corneal flap, LASIK with femtosecond laser for creating corneal flap has less effect on ocular surface and has mild symptoms of dry eye, the effect time is also shortened.