AIM: To investigate the best time for indwelling catheter of patients with chronic dacryocystitis after lacrimal drainage tube implantation.

METHODS: Totally 143 eyes of 143 patients with chronic dacryocystitis after lacrimal drainage tube implantation were selected in our hospital. They were divided into 3 groups including group A(50 eyes of 50 cases)with indwelling catheter in 9wk after tube implantation, group B(57 eyes of 57 cases)with indwelling catheter in 12wk after tube implantation, and group C(36 eyes of 36 cases)with indwelling catheter in 6wk after tube implantation. The clinical efficacy, visual acuity, incidence of epiphora, recurrence rate and incidence of postoperative complications with followed-up among three groups were compared.

RESULTS: On the day of extubation, the total effective rates of the three groups were 94%, 93% and 39%, the difference was statistically significant(P<0.0167). The total effective rates of group A and group B were better than those of group C, and the difference was statistically significant(χ²=30.830, 32.056, P<0.001). At 3mo after extubation, the total effective rates of the three groups were 56%, 51% and 36%, there was no significant difference(χ²=3.454, P=0.178). At 3mo after extubation, there was no significant difference in the visual acuity and the incidence of epiphora among the three groups(P>0.05). At 6mo after extubation, the recurrence rates of the three groups showed no significantly different(P=0.056). The incidence of postoperative complications in three groups were 4%(2/50), 7%(4/57)and 25%(9/36), the difference was statistically significant(χ²=11.048, P=0.004). The incidence of postoperative complications in group C was higher than that in groups A and B(χ²=6.499, 5.934; P=0.011, 0.015).

CONCLUSION: The clinical benefits of 6wk and 9wk after lacrimal drainage tube implantation are better than that of 12wk.