AIM:To study the changes of tear film and ocular surface after clear corneal incision phacoemulsification with different incision sizes.

METHODS:Ninety patients(90 eyes)from May 2013 to May 2014 in our hospital were enrolled. The patients were randomly divided into two groups. Forty-five patients(45 eyes)in group A: coaxial 2.2mm micro-incision phacoemulsification cataract extraction and intraocular lens(IOL)implantation; forty-five patients(45 eyes)in group B: the conventional coaxial 3.0mm small incision phacoemulsification cataract extraction and IOL implantation. The dry eye symptom(DES)score, break up time(BUT), Schirmer's Ⅰ test(SⅠt)and corneal fluorescein staining(CFS)score were assessed preoperatively and postoperatively.

RESULTS: At 10, 20 and 30d postoperatively, 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=-9.501, -10.070,-7.961; all P<0.05). 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=3.110, 4.477, 4.331; 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=-6.288, -4.012, -3.277; all P<0.05). The CFS score in two groups increased after operations, the CFS score of group B was significantly higher than those of group A and the differences were statistically significant(t=-11.672, -5.851, -4.677; all P<0.05). At 90d postoperatively, compared with the preoperative data, the DES score, BUT, SⅠt and CFS score in group A showed no statistically significant differences(t=1.290, 0.606, 0.559, 0.178; P>0.05). The DES score, BUT, SIt and CFS score in group B showed statistically significant differences(t=7.321, 4.071, 3.620, 4.214; all P<0.05).

CONCLUSION: Ocular surface has less damage and tear film has little influence at early stage after the coaxial 2.2mm micro incision phacoemulsmcation, compared with the conventional coaxial 3.0mm incision phacoemulsification surgery.