External dacryocystorhinostomy: do we really need to repair the posterior flap?

This study aims to compare a simplified technique of external dacryocystorhinostomy (DCR), where the posterior flap is excised, with the more traditional approach of double flap repair.

A prospective, comparative, single surgeon, single centre clinical trial was conducted of eighty-three patients who received external DCR, with either anterior and posterior flap anastomosis (Group A), or anterior flap anastomosis and excision of the posterior flap (Group B), in a tertiary referral hospital in Nepal. Patients with nasolacrimal duct obstruction and epiphora were assigned to one of two groups. Follow up was a minimum of 6 months for inclusion in the study. Success was defined objectively by irrigation of the puncta without regurgitation and subjectively by the absence of epiphora or discharge.

The overall success rate of external DCR was 89.2%, after a mean follow up of 13.5 ± 2.2 months. There was no difference in success between the two groups (p-value = 0.73), with 90.7% success in Group A and 87.5% in Group B. The frequency of complications was not statistically different between Groups A and B (p-value = 0.79).

Excision of the posterior flap and anastomosis of only the anterior flap is not disadvantageous to the outcomes of external DCR surgery when compared with the more traditional approach of anastomosis of both flaps. We believe this simplified procedure can be implemented as the standard technique for external DCR, particularly in developing nations such as Nepal.