AIM:To study the changes of tear film and ocular surface after the coaxial micro incision 2.2mm and 2.8mm in the phacoemulsification.

METHODS:Eighty-six patients(One hundred and six eyes)from 2014/06 to 2016/01 in our hospital were enrolled. The patients were randomly divided into two groups. Forty-four patients(Fifty-three eyes)in group A: coaxial 2.2mm micro-incision phacoemulsification cataract extraction and intraocular lens(IOL)implantation; Forty-two patients(Fifty-three eyes)in group B: the conventional coaxial 2.8mm small incision phacoemulsification cataract extraction and IOL implantation. The break up time(BUT), dry eye symptom(DES)score, Schirmer's I test(SⅠt)and lid-wiper epitheliopathy(LWE)score were assessed preoperatively and postoperatively.

RESULTS: At 1wk, 1 and 2mo postoperatively, the BUT in two groups decreased after operations, and the BUT of group B was significantly lower than those of group A, the differences were statistically significant(t=3.098, 4.512, 4.329; all P<0.05). The DES score in two groups increased, the DES score of group B was significantly higher than those of group A and the differences were statistically significant(t=-9.449, -10.029, -7.141; all P<0.05). The SⅠt in two groups increased after operations, the SⅠt of group B was significantly higher than those of group A and the differences were statistically significant(t=-6.293, -4.009, -3.283; all P<0.05). The LWE score in two groups increased after operations, the LWE score of group B was significantly higher than those of group A and the differences were statistically significant(t=-6.542, -5.125, -3.632; all P<0.05). At 6mo postoperatively, compared with the preoperative data, the BUT, DES score, SⅠt and LWE score in group A showed no statistically significant differences(t=0.659, 1.276, 0.548, 0.169; P>0.05). The BUT, DES score, SⅠt and LWE score in group B showed statistically significant differences(t=-4.063, 7.306, 3.621, 4.208; all P<0.05).

CONCLUSION: Ocular surface has less damage and tear film has little influence at early stage after the coaxial 2.2mm microincision phacoemulsification, compared with the conventional coaxial 2.8mm incision phacoemulsification surgery.