AIM: To analyze and evaluate the disinfection effects of secondary irrigation with different concentrations of povidone-iodine on conjunctival sac in cataract surgery.

METHODS: A total of 600 cataract patients(600 eyes)who underwent phacoemulsification and intraocular lens implantation in Ophthalmology Department of the hospital during the period from August 2016 to October 2017 were enrolled in the study. Their conjunctival sacs were disinfected for twice with povidone-iodine irrigation before surgery and after opening eyelid. According to different concentrations of povidone-iodine applied in secondary irrigation, the patients were divided into group Ⅰ(320 cases)and group Ⅱ(280 cases), with concentrations of 0.025% and 0.05%, respectively. The conjunctival sac swab specimens were obtained from the two groups after the first and second irrigation to conduct bacterial identification. The subjective comfort and conditions of conjunctival hyperemia and corneal epithelial damage were assessed during second irrigation. The occurrence of endophthalmitis after surgery was statistically analyzed.

RESULTS: There was no significant difference in positive rate of bacterial culture between group Ⅰ and group Ⅱ after the first and second irrigation with povidone-iodine(P>0.05). The incidence rates of subjective feelings such as foreign body sensation, itching sense, photophobia and red eye in group Ⅰ were significantly lower than those in group Ⅱ when second irrigation for conjunctival sac(P<0.05). After second irrigation for conjunctival sac, degree of conjunctival hyperemia and corneal epithelial damage in group Ⅰ was significantly lower than that in group Ⅱ(P<0.05). There were 2 eyes(0.6%)and 1 eye(0.4%)with endophthalmitisin in group Ⅰ and group Ⅱ, respectively(P>0.05).

CONCLUSION: There is high-efficiency disinfection effect of 0.025% povidone-iodine. Compared with 0.05% povidone-iodine, there are more advantages in improving subjective comfort, reducing conjunctival hyperemia and corneal epithelial damage, which is more suitable for patients undergoing cataract surgery.