Revision endonasal endoscopic dacrocystorhinostomy [REEDCR] with adjunctive intraoperative Mitomycin-C application

ABSTRACT

The aim of this study was to determine the efficacy of the adjunctive use of Mitomycin C in revision endonasal endoscopic dacrocystorhinostomy. A prospective randomized controlled study included 36 patients who underwent 44 endoscopic dacrocystorhinostomy [DCR] procedures. A total of 44 surgeries were divided into 2 equal groups, a traditional group [group I] underwent revision endonasal endoscopic dacrocystorhinostomy [REEDCR] and a Mitomycin-C adjunct to REEDCR group [group II]. In group I, the male to female ratio was 711 with mean age 36 years [range 25-56], while in group II the male to female ratio was 45 with mean age 37 years [range 23-58].The surgical procedures in both groups were exactly the same. The submucosal fibrosis from prior surgery was sharply dissected with removal of any scar tissue to enter the sac's interior. The sac opening was enlarged to a diameter of at least 20 mm. U - shaped intubation of the superior and inferior canaliculi was performed with a thin silicone tube. A piece of neurosurgical cottonoid saturated with 0.5 mg/ml Mitomycin-C was placed over osteotomy site for 5 minutes in group II surgeries. The silicone tubes were removed at 6 months after surgeries in all patients. The REEDCR results were assessed subjectively and objectively at the end of 1[st] week after surgery and during the follow up period at 3[rd], 6[th] and 9[th] postoperative months. Subjective assessment was based on the patients symptom of epiphora. The objective assessment of anatomical and functional outcomes included irrigation test, functional endoscopic dye test [FEDT] as well as nasal endoscopic assessment of rhinostomy site [nasolacrimal ostium size and pathological conditions]. Surgery was considered successful when the patient had no or minimal conditional epiphora and the fluid passed freely without reflux on lacrimal irrigation. In group II [Mitomycin group], 86% [19/22] eyes got significant improvement of the epiphora symptom compared to 77% [17/22] in group I [conventional group]. The higher subjective improvement in group II was associated with a higher objective improvement based on positive irrigation test in 86% and positive FEDT in 82% of patients compared to group I [77% irrigation test positive and 73% FEDT test positive]. Endoscopic nasal examination of rhinostomy site in group I failed cases revealed scar tissue formation in 3 cases [14%] and granulation tissue formation in 2 cases [9%]. In group II, assessment of rhinostomy site revealed scar tissue formation in 9% of cases [2 out of 22] while no granulation tissue formation was detected in this group. In group II, the mean rhinostomy diameter decreased from 14 +/- 1.2 mm on the first postoperative week to 10.3 +/- 2.1mm at the 3rd. month, 8.2 +/- 2.3mm at the 6th.month and 5.7 +/- 1.8mm at the 9th.month. This diameter change was significantly less than that in group I. By the end of follow up period the mean rhinostomy diameter in group II [5.7 +/- 1.8mm] was significantly greater than that in group I [3.6 +/- 1.4mm]. The adjunctive intra-operative Mitomycin-C local application increases the success rate of revision endonasal endoscopic DCR with a high safety profile, we suggest that Mitomycin-C reduces the fibrous adhesion, scarring and granulation tissue formation at the ostium area preventing further shrinkage of the final ostium. Large scale-study with long follow up period and different Mitomycin-C concentrations and exposure time is needed