Usefulness of the Hook knife in flexible endoscopic myotomy for Zenker’s diverticulum

AIM To investigate the outcome of flexible endoscopic myotomy performed with the Hook knife in patients with symptomatic Zenker’s diverticulum(ZD).METHODS All consecutive patients treated for ZD at our institution between 7/2012 and 12/2016 were included.The flexible endoscopic soft diverticuloscope-assisted technique with endoclips placement and Hook knife myotomy were performed in all patients.Here we report a retrospective review of prospectively collected data.Demographics,dysphagia score(Dakkak and Bennett),associated symptoms and adverse events were collected pre-procedure,at 2 and 6 mo post-procedure,and at the end of the follow-up period.Clinical success was defined as at least 1-point improvement in dysphagia score and a residual dysphagia score≤1,with no need for reintervention.Dysphagia scores were compared before treatment and at end-of-follow-up using the Wilcoxon test.RESULTS Twenty-four patients were included.Mean size of ZD was 3.0 cm(range 2-8 cm).Mean number of sessions was 1.17/patient(range 1-3 sessions).Overall clinical success was 91.7%.Two adverse events(8.3%) occurred,and both were managed conservatively.No bleeding or perforation was reported.Mild pain was reported by 9 patients(37.5%).Median hospital stay was 1 d(range 1-6).Median follow-up was 19.5 mo(range 6-53).Mean ± SD dysphagia score was 2.25±0.89 before treatment and decreased to 0.41 ± 0.92 at end-of-follow-up(P<0.001).Regurgitation and cough dropped from 91.7% and 50% to 12.5% and 0% at the end of follow-up,respectively.Recurrence was observed in 3 patients,and all 3 were symptom-free after one more session.CONCLUSION The Hook knife,used in the soft diverticuloscope-assisted technique setting,is efficient and safe for treatment of ZD.