Pathogenesis and Prevention of Postoperative Endophthalmitis after Cataract Surgery from 2004 to 2016 in the Single-Center of the Guangming Project

Objective: To analyze the incidence and influencing factors of postoperative endophthalmitis after cataract surgery in the Guangming Project, and to recommend precautionary actions. Methods: In this retrospective study of cases from January 2004 to December 2016 in Jinhua Eye Hospital, we collected clinical data of cataract surgery patients who developed postoperative endophthalmitis. Then we analyzed the incidence, clinical features, and possible preventive measures. The effects of different surgical procedures and different perioperative management protocols were analyzed. The Fisher exactness test was used for statistical analysis. Results: Sixteen cases of postoperative endophthalmitis occurred after 20, 131 cataract surgeries during the study period; thus, the cumulative incidence was 0.079%. After 5, 371 cases of small incision extracapsular cataract extraction, there were two cases of postoperative endophthalmitis (0.037%). After 14, 760 cases of phacoemulsification, there were 14 cases of postoperative endophthalmitis (0.095%). There was no significant difference in the incidence of postoperative endophthalmitis between the two surgical methods (P=0.265). There was also no difference in the incidence of postoperative endophthalmitis between procedures in which the eyelashes were trimmed (incidence 0.121%) or not trimmed (incidence 0.062%, P=0.29). The incidence of postoperative endophthalmitis for patients using 0.5% povidone iodine to wash the conjunctival sac before surgery was 0.059%, while the incidence for patients not using the povidone wash was 0.174%, P=0.04). According to the description of the cause of the disease, we found that 4 cases of male patients have a clear incentive, accounting for 25%, of which one patient shampoo a day before the disease occurring; one patient dismantle the old wall of its own roof collapse one day before the disease occurring; One patient covered surgery eye by their own buied gauze; One patient droped the surgery eye only with one of the discharged medicine, and only once a day. There were no obvious causes in the remaining 12 patients. In addition, follow-up intravitreal surgery found that the clear corneal incision was oblique and poorly closed in two patients. Conclusions: The incidence of postoperative endophthalmitis after cataract surgery is 0.079%. Pre-surgical washing of the conjunctival sac with 0.5% povidone iodine before the operation can reduce the incidence of postoperative endophthalmitis. The incidence of postoperative endophthalmitis can probably be further reduced by providing patients with clear pre- and postoperative medical and behavioral instructions to ensure that medications are taken properly, and that inappropriate activities are avoided. Key words: endophthalmitis; phacoemulsification; cataract extraction; postoperative complications