AIM: To investigate the methods, effect and security of the micro-invasive treatments for chronic dacryocystitis with the fifth generation lacrimal endoscope, and to evaluate its clinical application.

METHODS:In this case-control study, 120 patients(120 eyes)with chronic dacryocystitis were collected from April 2013 to July 2014 in our department. The patients were randomly divided into observation group(the fifth generation endoscopic lacrimal microdrill with full intubation group, 62 cases 62 eyes)and control group(external dacryocystorhinostomy group, 58 cases 58 eyes). The effective rate and complication were observed and compared between two groups after operation. Statistical package SPSS 13.0 was used for statistical analysis.

RESULTS: The effective rate of observation group was 91.9%, and control group was 96.6%, there was no statistically significant difference between the two groups(P>0.05). Hemorrhage occurred in observation group and control group was 35.5% and 79.3%, respectively, additionally palpebral oedema was 19.4% and 55.2%, respectively, there were statistically significant differences between the two groups(P<0.05). There was no serious intraoperative and postoperative complications in two groups.

CONCLUSION: The fifth generation lacrimal endoscope is more flexible than traditional one-piece lacrimal endoscope during the operation, it can treat chronic dacryocystitis by directly observing nasolacrimal duct obstruction site and dredge the obstruction under microdrilling with full lacrimal intubation. It was not only good clinical curative effect, but also safer, more efficient than the external dacryocystorhinostomy, visualization and micro-invasive are its special advantage, and worthy for further clinical application.