Abstract:Objective To evaluate the efficiency of cutting off the granulation tissue, generating after endoscopic endonasal dacryocystorhinostomy (En-DCR), at the rhinostomy site by a novel suction and cutter instrument.Methods Patients diagnosed as primary acquired nasolacrimal duct obstruction from January 2017 to March 2020 were recruited and underwent En-DCR. The healing of the ostium and the presence of granulation tissue around it were mainly assessed post En-DCR by endoscopic examinations. The cases in which tear drainage function was influenced by the granulation tisse were enrolled. On the basis of the comparative position of granulation to the ostium, the cases were divided into inner group and edge group. The granulation tissue was cut off directly by a novel unique suction and cutter instrument. All the cases were followed up at 1 week, 2 weeks, 1 month, 2 months, 3 months, 6 months and 9 months after excision. The incidence of granulation tissue formation after resection and the therapeutic effect of this operation were evaluated by several methods, such as endoscopy, slit lamp examination, fluorescein dye disappearence test, lacrimal passage flushing test, etc, and the results of the two groups were compared by chi square test.Results 52 patients (52 eyes) were enrolled in this study, among of them, 16 in inner group and 36 in edge group. With a follow-up of 9 months after granulation excision, the success rate was 86.5% in total, 87.5% in inner group and 86.1% in edge group. No statistical difference was found in success rate between the two groups (P > 0.05). And neither group showed significant bleeding or other complications.Conclusion As the high rate of success and low incidence of complications, we believe that granulation tissue excision by a novel suction-cutting instrument is a good choice for patients with granulation tissue formation at the ostium area after En-DCR.