AIM: To observe the clinical effects of modified endoscopic dacryocystorhinostomy(EDCR)for chronic dacryocystitis and try to find out an effective adjuvant method to improve the long-term effect of the modified surgery.

METHODS: Totally 136 cases(158 eyes)of chronic dacryocystitis were enrolled in the study and randomly divided into two groups:treatment group(80 eyes)and control group(78 eyes).The treatment group underwent the modified EDCR(intraoperative mytomycin C combined with silicone tube implatation and the use of tobramycin and dexamethasone eye ointment).The control group was only applyed mytomycin C during EDCR.The postoperative follow-up period was for 3-12mo.

RESULTS: At 6mo postoperatively,the cure rate and total effective rate of the treatment group were 95.0%, 98.8% respectively,and the control group of it were 75.6%, 93.6%.The effective rate of the treatment group was higher than that of the control group significantly(χ²=11.90,P<0.05).

CONCLUSION: The modified EDCR is a new surgical method which can prevent postoperative cicatricial adhesion and elevate surgical effective rate, and it has clear field, minimal invasion, quick recovery, exact effect and less recurrence.