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.