AIM: To explore the effect of different corneal incision size on change in tear function after phacoemulsification cataract surgery in type 2 diabetics.

METHODS:One hundred and fifty patients with type 2 diabetes(150 eyes)from Jan. 2015 to Oct. 2015 in our hospital were enrolled. The patients were randomly divided into two groups. Seventy-five patients(75 eyes)in group A: coaxial 2.2mm micro-incision phacoemulsification cataract extraction and intraocular lens(IOL)implantation; seventy-five patients(75 eyes)in group B: the conventional coaxial 3.0mm small incision phacoemulsification cataract extraction and IOL implantation. The difference of demographic characteristics between two groups were insignificant. The ocular surface disease index(OSDI), corneal sensation, break up time(BUT)and Schirmer's Ⅰ test(SⅠt)were examined preoperatively and 1wk, 1, 3 and 6mo postoperatively.

RESULTS:At 1wk, 1 and 3mo postoperatively, the OSDI score in two groups increased and the OSDI score of group B was significantly higher than those of group A and the differences were statistically significant(all P<0.05). The corneal sensation in two groups decreased after operations and the corneal sensation of group B was significantly lower than those of group A and the differences were statistically significant(all P<0.05). The SⅠt in two groups decreased after operations and the SⅠt of group B was significantly lower than those of group A and the differences were statistically significant(all P<0.05). At 1wk and 1mo postoperatively, the BUT in two groups decreased after operations and the BUT of group B was significantly lower than those of group A and the differences were statistically significant(all P<0.05). At 6mo postoperatively, no significant change was found in the OSDI score, corneal sensation, BUT and SⅠt of group A compared with preoperatively(all P>0.05). At 6mo postoperatively, the differences of OSDI score and corneal sensation in group B were statistically significant compared with preoperatively(all P<0.05)while no significant change was found in the BUT and SⅠt of group B(all P>0.05).

CONCLUSION:Phacoemulsification surgery with 2.2mm corneal micro-incision has less effect on change in tear function comparing to the 3.0 mm incision control, which can be applied particularly in patients with type 2 diabetes.