Does Mucosal Preservation in Endonasal Dacryocystorhinostomy Improve Long-Term Success?

With the expansion of endonasal techniques, endoscopic dacryocystorhinostomy (eDCR) has gained popularity over conventional open approaches over the last decade. Prior literature has supported the use of eDCR with outcomes that are comparable to traditional external approaches. Preservation of the posteriorly based mucosal flap was first described by Wormald in a 2002 prospective cohort study with success rates approaching 96%. Other case series with mucosal flap preservation published shortly thereafter also reported success rates ranging from 90%–96%. However, other reports in cohorts without mucosal preservation have shown similar efficacy suggesting mucosal preservation may not be essential in achieving long-term successful outcomes. This Best Practice review seeks to answer whether eDCR outcomes differ with or without the preservation of mucosal flaps. Several studies have examined outcomes in eDCR with and without preservation of mucosal flaps. Ji et al. performed a randomized control trial (RCT) to identify the efficacy of mucosal preservation. A total of 110 patients were randomized to undergo either eDCR with a mucosal flap (49%) or without a mucosal flap (51%). The primary endpoints included lacrimal irrigation, absence of epiphora, and discharge at 1, 3, 6, and 12-month follow-up intervals. They demonstrated statistically significant benefit in the mucosal flap group with 98% success versus 84% in those without a mucosal flap (p < 0.005). They also found more granulation and scar tissue in the group without a mucosal flap.1 A second double-blinded RCT by Khalifa et al. included a total of 77 patients randomized to either eDCR with a mucosal flap (49%) or without a mucosal flap (51%). Their primary endpoints also included lacrimal irrigation, absence of epiphora, and discharge. Patients were followed weekly for 1 month, biweekly for 3 months, and monthly thereafter. They found no statistical difference in success between groups (92% with mucosal flap vs. 87% without flap, p > 0.05) at 6 and 12-month follow-up intervals. However, they found that the group without mucosal preservation required significantly more debridements.2 Other studies have reported similar outcomes in eDCR without the preservation of mucosal flaps. A recent retrospective study by Kingdom et al. evaluated long-term outcomes after eDCR without preservation of mucosal flaps. Their study included 88 patients totaling 103 procedures (87 primary and 16 revision cases) with a mean follow-up of 29 months. Primary endpoint measures were similar to the aforementioned studies. They found 89% of all patients had complete resolution of epiphora. Of those undergoing primary DCRs, complete resolution was noted in 93% of primary cases. Objective anatomic patency based on lacrimal irrigation was confirmed in 98% of cases. These outcomes are comparable to those previously reported in the literature suggesting mucosal flap preservation is not required to achieve long-term successful outcomes in eDCR.3 Recent case–control studies comparing the two techniques support these findings. Zloto et al. retrospectively reviewed success rates of eDCR with and without mucosal flaps. Their study included 107 patients of which 51 patients comprised the group without a mucosal flap and 56 patients comprised the group with mucosal flap preservation. They found no statistically significant difference between surgical success (82% without flap vs. 87% with flap, p = 0.478) or significant differences in complications. The authors concluded no benefit to adding flap preservation to conventional eDCR.4 Lastly, a retrospective review by Kansu et al. also found no significant difference in success rates or complications between groups undergoing eDCR with and without preservation of a mucosal flap. However, they did find that preservation of posteriorly based nasal mucosal flap can decrease the formation of post-operative granulation tissue5 (Table I). Group A Mucosal Flap: 54 patients Group B No Flap: 57 patients Group A: 98% Group B: 84% p < 0.05 Significantly more granulation tissue in Group B Group A Mucosal Flap: 38 patients Group B No Flap: 39 patients Group A: 92% Group B: 88% p > 0.05 Significant more debridments in Group B 88 patients 103 procedures: 87 primary 16 revision Mean: 28.7 months Range: 6–114 months Epiphora, Complete Resolution All: 89% Primary: 93% Revision: 69% Anatomic Patency: 98% Group A Mucosal Flap: 56 patients Group B No Flap: 51 Patients Absence of symptoms Patent osteotomy by: Fluoresceine dye clearance test, lacrimal irrigation, and probing Group A: 87% Group B: 82% p = 0.478 Group A Mucosal Flap: 27 Patients Group B No Flap: 47 Patients Group A: 100% Group B: 88% p = 0.08 Higher rate of granulation and synechia in group B Although the number of RCTs is lacking, the current literature suggests mucosal flap preservation may improve outcomes following eDCR. Mucosal preservation may help best in the immediate post-operative period as it is associated with decreased granulation tissue and synechia. However, with regard to long-term outcomes, one RCT demonstrated improved outcomes whereas other studies have shown no statistical difference. This may be attributed to the high success rate of eDCR regardless of the technique used. Higher-powered studies with larger cohorts are needed to elucidate these findings. These recommendations are based on two RCTs (level 1), two case–control studies (level 3), and one retrospective case series (level 4).