Peroral endoscopic myotomy for the treatment of esophageal diverticulum: an experience in China

Magnet-assisted diverticuloplasty for treating the symptomatic esophageal diverticulum: a case series (with video)

BACKGROUND

The development of the magnetic compression technique (MCT) for the gastrointestinal (GI) tract has been widely applied in the treatment of biliary strictures, esophageal atresia, and GI anastomoses. Our team combined the MCT and minimally invasive endoscopic operation to propose a novel alternative procedure called magnet-assisted diverticuloplasty (MAD) for treating various esophageal diverticula. This case series aimed to report the effectiveness, safety, and our experience of MAD.

METHODS

This retrospective case series included patients with symptomatic esophageal diverticulum (SED) who underwent MAD between November 2017 and June 2022 in West China Hospital, Sichuan University. The patients' symptomatic scores were accessed by Eckardt symptomatic scores. The telephone follow-up period ended in March 2023. The primary outcome of the study was clinical success. Secondary outcomes included the technical success of MAD, procedure time, hospitalization, recurrence, and adverse events.

RESULTS

We reported 6 patients with SED who underwent MAD (3 with Zenker's, 1 with middle, and 2 with lower esophageal diverticulum). The technical success rate was 100% (6/6) and no adverse events were reported. The median procedural duration was 22.5 min (interquartile range (IQR) 18.5). The mean hospitalization was 2 days (range 1-3). The median time of follow-up endoscopy was on postoperative day 18 (IQR 31), revealing a shortened diverticular septum under endoscopic examination. After a median telephone follow-up of 23 months (IQR 36), the median total symptomatic score decreased significantly from 4.00 (IQR 3.25) to 1.00 (IQR 2.00) (P = 0.015). The clinical success rate was 83.3% (5/6), and only one patient had recurrent symptoms two years after MAD.

CONCLUSION

MAD provided a novel method for treating SED. Our limited experience suggested that MAD could be minimally invasive and effective. More extensive, multicenter prospective studies were needed to assess this technique further.

Clinical outcomes of peroral endoscopic myotomy with and without septotomy for management of epiphrenic diverticula: an international multicenter experience (with video)

BACKGROUND AND AIMS

There are few data favoring the need for septotomy at the time of peroral endoscopic myotomy (POEM) or if POEM alone is sufficient. Our aim was to compare POEM outcomes with and without septotomy (POEM+S or POEM-S) in patients with symptomatic epiphrenic diverticula (ED) and an underlying motility disorder.

METHODS

This was an international, multicenter retrospective study involving 21 centers between January 2014 and January 2023. Patients with ED and an underlying motility disorder who underwent POEM were included. The primary outcome was clinical success (Eckardt score [ES] ≤3 or a 1-point drop in ES for patients with baseline ES <3) without the need for repeat surgical/endoscopic interventions during follow-up.

RESULTS

A total of 85 patients (mean age, 64.29 ± 17.1 years; 32 [37.6%] female) with ED and underlying motility disorder underwent POEM+S (n = 47) or POEM-S (n = 38). Patients in the POEM+S group had a significantly higher mean pre-POEM ES (7.3 ± 2.1 vs 5.8 ± 2; P = .002). The most common indication for POEM was achalasia (51% in the POEM+S cohort and 51.8% in the POEM-S cohort; P = .7). A posterior approach was favored in the POEM+S group (76.6% vs 52.6%; P = .02). A similar rate of technical success was seen in both groups (97.9% vs 100%; P = .1). The rate of adverse events was similar between the 2 cohorts (4.2% vs 8.1%; P = .6). The median length of hospital stay after POEM-S was significantly longer compared with POEM+S (2 days [interquartile range (IQR), 1-4 days] vs 1 day [IQR, 1-2 days]; P = .005). Clinical success was equivalent between the 2 groups (83% vs 86.8%; P = .6) at a median follow-up duration of 8 months (IQR, 3-19 months).

CONCLUSIONS

In patients with ED and an underlying motility disorder, both POEM+S and POEM-S are equally safe and effective, with similar procedure duration and a low recurrence rate at short-term follow-up. Future comparative prospective studies with long-term follow-up are required to validate these findings.

Emerging indications for third space endoscopy

This chapter will explore the recent advancements and innovations in the field of third space endoscopy. The traditional principles of per-oral endoscopic myotomy and endoscopic submucosal dissection have been applied to offer solutions to traditionally difficult to manage problems including esophageal diverticula, post-fundoplication dysphagia, post-sleeve gastrectomy stricture, bariatric procedure and Hirschsprung disease. Typically, these problems were managed surgically with potentially high rates of morbidity and mortality; however, the principles of third space endoscopy offer a safer and less invasive option for management. All of these applications of third space endoscopy are less than a decade old with some emerging in the last 1-2 years. In this chapter, we will explore the pathophysiology of these diseases and how third space endoscopy can offer a solution. We will also review the relevant literature along with the safety and effectiveness of the proposed innovations.

Direct diverticular peroral endoscopic myotomy for the treatment of thoracic esophageal diverticula: technique and outcomes

BACKGROUND

 Diverticular peroral endoscopic myotomy (POEM) is an alternative to surgery for the management of symptomatic thoracic esophageal diverticula. Conventionally, this requires proximal tunnel formation but a direct approach may simplify the technique. Herein, we report the outcomes of direct diverticular-POEM (DD-POEM).

METHODS

 We conducted a single-center prospective observational study evaluating DD-POEM. This involved a direct approach to the diverticulum. Success was defined as an Eckardt score of ≤ 3 without the need for reintervention.

RESULTS

 10 patients underwent DD-POEM (median age 72 years; interquartile range [IQR] 14.3; male 60 % [n = 6]). Median diverticulum size was 40 mm (IQR 7.5) and median location was 35 cm from the incisors (IQR 8.3). Five patients (50 %) had an underlying dysmotility disorder. The median procedure duration was 60 minutes (IQR 28.8). There were no adverse events. The median hospital stay was 1 day (IQR 0.75). The pre-procedure median Eckardt score of 6 (IQR 4) significantly improved to 0 (IQR 0.75; P < 0.001) at a median follow-up of 14.5 months (IQR 13.8). Success was achieved in all patients.

CONCLUSIONS

 DD-POEM was a safe technique for the management of thoracic esophageal diverticula. Owing to its simplicity and excellent performance it should be further evaluated for the treatment of this disorder.

Diverticular peroral endoscopic myotomy (D-POEM) for symptomatic oesophageal diverticulum: a multicentre cohort study with a minimum follow-up of 3 years

OBJECTIVE

To evaluate the medium- and long-term outcomes of diverticular peroral endoscopic myotomy (D-POEM) for symptomatic oesophageal diverticulum.

METHODS

Consecutive patients with symptomatic oesophageal diverticulum who underwent D-POEM from 1st May 2016 to 1st April 2020 in 6 centres were extracted and researched. Symptoms assessed by the modified Eckardt score were registered pre- and post-D-POEM at 1, 6, 12, 24 and 36 months.

RESULTS

A total of 34 patients with Zenker's diverticulum (ZD, n = 12), mid-oesophageal diverticulum (MED, n = 12), and epiphrenic diverticulum (ED, n = 10) were included. Complete septotomy was achieved in a mean of 39.15 min, with 100% technical success. No severe intraoperative or postoperative complications were observed. Five patients exhibited subcutaneous emphysema, while 1 had mucosal injury. The mean Eckardt score was 8.59 preoperatively and 2.56 at 1 month, 2.09 at 6 months, 2.21 at 12 months, 2.15 at 24 months, and 2.21 at 36 months postoperatively. The total clinical success rates at 1, 6, 12, 24 and 36 months postoperatively were 97.1%, 97.1%, 94.1%, 91.2%, and 88.2%, respectively. With a median follow-up of 47.2 months, four patients suffered symptom relapse, with a total clinical success rate of 88.2%. A long disease duration, a high Eckardt score, and coexistence of achalasia were identified as risk factors for symptomatic recurrence by multivariable Cox analysis.

CONCLUSIONS

D-POEM is an effective and durable treatment for patients with symptomatic oesophageal diverticulum.

The utility of intraoperative endoscopy in esophagogastric surgery

Flexible endoscopy (FE) plays a major role in the diagnosis and treatment of gastrointestinal disease. Although its intraoperative use has spread over the years, its use by surgeons is still limited in our setting. FE training opportunities are different among many institutions, specialties, and countries. Intraoperative endoscopy (IOE) presents peculiarities that increase its complexity compared to standard FE. IOE has a positive impact on surgical results, due to increased safety and quality, as well as a reduction in the complications. Due to its innumerable advantages, its intraoperative use by surgeons is currently a current project in many countries and is part of the near future in others because of the creation of better structured training projects. This manuscript reviews and updates the indications and uses of intraoperative upper gastrointestinal endoscopy in esophagogastric surgery.

Multimodal Endoscopic Management of Esophageal Perforations as a Complication of Peroral Endoscopic Myotomy for a Zenker's Diverticulum

Zenker's diverticulum develops because of a weakness in Killian's triangle, leading to a mucosal and submucosal herniation. Its treatment has evolved from morbid surgical interventions to safer endoscopic techniques such as peroral endoscopic myotomy (Z-POEM). Despite being a safe technique, Z-POEM is not free of complications such as perforations, bleeding, pneumoperitoneum, and pneumothorax, for which new endoscopic techniques have been developed. We present the case of a 53-year-old man taken to a Z-POEM who postoperatively presented dehiscence of the mucosotomy and a mediastinal collection, managed with a vacuum-assisted endoscopic closure device.

Peroral endoscopic myotomy (POEM) for esophageal diverticula

Esophageal diverticula (ED) are uncommon, mostly seen in elderly and can present with a multitude of symptoms. Of the three types of ED, epiphrenic and mid-esophageal diverticulum are still rare. These are often associated with esophageal motility disorder, which contributes to its development. The key step in the management of such symptomatic ED is the division of the septum and tackling the underlying motility dysfunction, if any. Traditional surgical options have high morbidity and mortality while flexible endoscopic septal division cannot adequately manage epiphrenic diverticulum with motility dysfunction. The technique of submucosal space creation and peroral endoscopic myotomy (POEM) has been used to treat a host of esophageal diseases such as achalasia. POEM has been recently described for the management of ED. Two different strategies have been described for tackling using POEM, namely, diverticular POEM (D-POEM) and salvage POEM (S-POEM). While D-POEM entails division of the septum and esophageal myotomy, S-POEM requires only esophageal myotomy without septum division. Multiple retrospective studies in the recent years have described use of POEM for the management of different types of ED with good safety and efficacy with low recurrence rate. This review encompasses a detailed account of the technical steps, pre- and post-procedure evaluation and literature review of safety, efficacy, adverse events, and recurrence rates of the use of POEM for ephiprenic and mid-esophageal diverticulum. We have also proposed a management algorithm based on the type of underlying motility dysfunction and the size of the diverticulum.

Efficacy and safety of peroral endoscopic myotomy for esophageal diverticula

Background and study aims  Epiphrenic diverticula are rare and mainly occur in patients with underlying esophageal motility disorders. The current standard treatment is surgical diverticulectomy often combined by myotomy and is associated with significant adverse event (AE) rates. The aim of this study was to examine the efficacy and safety of peroral endoscopic myotomy in reducing esophageal symptoms in patients with esophageal diverticula. Patients and methods  We performed a retrospective cohort study including patients with an esophageal diverticulum who underwent POEM between October 2014 and December 2022. After informed consent, data were extracted from medical records and patients completed a survey by telephone. The primary outcome was treatment success, defined as Eckardt score below 4 with a minimal reduction of 2 points. Results  Seventeen patients (mean age 71 years, 41.2 % female) were included. Achalasia was confirmed in 13 patients (13 /17, 76.5 %), Jackhammer esophagus in two patients (2 /17, 11.8 %), diffuse esophageal spasm in one patient (1 /17, 5.9 %) and in one patient no esophageal motility disorder was found (1 /17, 5.9 %). Treatment success was 68.8 % and only one patient (6.3 %) underwent retreatment (pneumatic dilatation). Median Eckardt scores decreased from 7 to 1 after POEM (p < 0.001). Mean size of the diverticula decreased from 3.6 cm to 2.9 cm after POEM (p < 0.001). Clinical admission was one night for all patients. AEs occurred in two patients (11.8 %) which were classified as grade II and IIIa (AGREE classification). Conclusions  POEM is effective and safe to treat patients with esophageal diverticula and an underlying esophageal motility disorder.

Pharyngoesophageal diverticulum mimicking thyroid nodules: Some interesting ultrasonographic signs

Objective

To analyze the ultrasonographic features of pharyngoesophageal diverticulum (PED) mimicking thyroid nodules and to explore the clinical value of ultrasonography in the diagnosis of PED.

Method

The sonographic findings of 68 patients with PED were retrospectively reviewed. According to the diverticulum echo intensity characteristics, the lesions were divided into solid nodular diverticulum, gas-containing nodular diverticulum, liquid-containing nodular diverticulum, and atypical diverticular changes; and the ultrasonographic manifestations were compared among the four groups.

Results

30/68 were solid nodular diverticula. The diverticulum cavity was oval or elliptic with a clear border, and the diverticulum wall suggested exhibited a typical hyper-hypo-hyper-echogenic pattern. The diverticulum wall and esophageal wall were seen to be continuous if multiple sections were scanned, and hypoechoic walls showed punctate blood flow. 29/68 diagnosed with air-containing nodular diverticulum, lesions appeared with gas-like hyper-echogenicity internally, with some amount of gas and change in the tail pattern during swallowing. 6/68 patients were diagnosed with liquid-containing nodular diverticulum, and the main ultrasonic manifestations were an anechoic internal diverticulum cavity that was clearly bounded from the thyroid but continuous with the esophageal wall, with a typical hyper-hypo-echoless pattern from the outside to the inside. Another 3/68 were found to have atypical diverticular changes, regional convexities of the esophageal wall with unfashioned nodules. The convex segment was continuous with the hyper-hypo-echogenic esophageal wall and could be seen on slitting scanning.

Conclusion

Overall, PEDs mimicking thyroid nodules have specific ultrasonographic features. Familiarity with them can avoid missed diagnoses and misdiagnoses.

Role of Endoscopy in Motility Disorders of Upper Gastrointestinal Tract

Gastrointestinal motility disorders have a wide range of symptoms and affect patients' quality of life. With the advancement of endoscopy, the diagnostic and therapeutic roles of endoscopy in motility disorders is becoming more significant. Endoscopy is necessary to rule out possible organic diseases in patients with suspected motility disorders and provide significant clues for their diagnosis. Moreover, interventional endoscopy may be a primary or alternative treatment option for selected patients with motility disorders, and it is becoming a promising field as new therapeutic applications are developed and utilized for various motility disorders. This review may provide suitable indications for the use of endoscopy in diagnosing and treating motility disorders of the upper gastrointestinal tract.

Indications and Outcomes of Per Oral Endoscopic Myotomy from Mouth to Anus

Third space endoscopy or submucosal endoscopy using a mucosal flap valve allows secure access to the submucosal and deeper layers of the gastrointestinal tract without the risk of a full-thickness perforation. This allows the performance of submucosal tunneling and myotomy for spastic segments of the gastrointestinal tract. Per oral endoscopic myotomy (POEM) has been described for the treatment of achalasia cardia and other spastic esophageal disorders and is widely implemented. Endoscopic pyloromyotomy (G-POEM) has been performed for the treatment of refractory gastroparesis. Z-POEM for Zenker's diverticulum, D-POEM for epiphrenic diverticulum, and per-rectal endoscopic myotomy for treatment of Hirschsprung's disease are described..

Peroral Endoscopic Myotomy Technique, from Mouth to Anus

The peroral endoscopic myotomy (POEM) procedure, as described over 10 years ago, is a submucosal endoscopy procedure that allows access to the muscle layers throughout the gastrointestinal (GI) tract. With this access, and ability to cut the muscle fibers, POEM can be performed not only for motility disorders but for structural pathology as well, such as Zenker diverticulum. Regardless of the location, there are 4 steps to the procedure: mucosotomy, submucosal tunneling, myotomy, and mucostomy closure. This review outlines these key components as well as variations in techniques for POEM throughout the GI tract.

Submucosal tunneling endoscopic septum division for esophageal diverticulum with a median follow-up of 39 months: a multicenter cohort study

BACKGROUND AND AIMS

Submucosal tunneling endoscopic septum division (STESD) is an endoscopic minimally invasive technique for treating esophageal diverticulum. The objectives of this study were to evaluate the safety and efficacy of STESD and its impact on patients' quality of life.

METHODS

This study included consecutive patients who underwent STESD for esophageal diverticulum from April 2016 to August 2020 in 2 centers (Zhongshan Hospital, Fudan University and Tianjin First Central Hospital). Esophagogram and endoscopic examination were performed before STESD and 30 days after STESD. Patients completed the 36-item Short Form survey (SF-36) before STESD and 1 year after surgery. Clinical symptoms were assessed via telehealth every 6 months until August 2021. Costamagna and Eckardt scores were used to evaluate changes in symptoms.

RESULTS

Twenty-one patients were included. Mucosal injury 1 to 2 cm below the septum occurred in 2 patients. No severe surgical adverse events were observed. Median duration of follow-up was 39 months (range, 12-63). Total SF-36 scores increased from 118.7 ± 18.6 before STESD to 132.4 ± 9.1 at 1 year after the procedure (P = .007). SF-36 subscales of general health (P = .002), vitality (P = .004), social functioning (P = .030), and mental health (P = .020) improved significantly after STESD. The mean Costamagna score decreased from 3.83 ± 1.33 to 1.67 ± 1.51 (P = .010), whereas the mean Eckardt score decreased from 3.50 ± .90 to 1.25 ± 1.76 (P = .002). One patient developed symptom recurrence at 10 months after STESD.

CONCLUSIONS

STESD is a safe and valid endoscopic minimally invasive surgery for esophageal diverticulum, which can reduce symptoms and improve quality of life.

POEM, GPOEM, and ZPOEM

Our tripartite narrative review discusses Peroral Endoscopic Myotomy (POEM), gastric POEM (GPOEM) and POEM for Zenker's diverticula (ZPOEM). POEM is the prototypical procedure that launched the novel "3rd space endoscopy" field of advanced endoscopy. It revolutionized achalasia therapy by offering a much less invasive version of the prior gold standard, the laparoscopic Heller myotomy (HM). We review in detail indications, outcomes, technique variations and comparative data between POEM and HM particularly with regard to the hotly debated issue of GERD. We then proceed to discuss two less illustrious but nevertheless important offshoots of the iconic POEM procedure: GPOEM for gastroparesis and ZPOEM for the treatment of hypopharyngeal diverticula. For GPOEM, we discuss the rationale of pylorus-directed therapies, briefly touch on GPOEM technique variations and then focus on the importance of proper patient selection and emerging data in this area. On the third and final part of our review, we discuss ZPOEM and expound on technique variations including our "ultra-short tunnel technique". Our review emphasizes that, despite the superiority of endoscopy over surgery for the treatment of hypopharyngeal diverticula, there is no clear evidence yet of the superiority of the newfangled ZPOEM technique compared to the conventional endoscopic myotomy technique practiced for over two decades prior to the advent of ZPOEM.

Per Oral Endoscopic Myotomy for the Management of Large Esophageal Diverticula (D-POEM): Safe and Effective Modality for Complete Septotomy

With the advent of the technique of sub-mucosal tunnelling, peroral endoscopic myotomy (POEM) has been used for the treatment of esophageal diverticulum, which otherwise is a recurring problem with conventional flexible endoscopic treatment due to incompleteness of septotomy. This study reports our experience of the use of diverticular POEM (D-POEM) technique in the management of large esophageal diverticulum. This is a retrospective study of prospectively maintained database including all consecutive patients with symptomatic esophageal diverticulum presenting at a tertiary care academic center. D-POEM was performed using the technique of submucosal tunnelling and septotomy. Besides baseline parameters, technical success, clinical success, size of diverticula, procedure time, complications and symptom recurrence on follow up were noted. A total of five patients (4 males; median age 72) were included with an average Charlson comorbidity index of 3.2 ± 0.8. Of them, three had Zenker's while two had epiphrenic diverticulum. The median symptom duration was 12 months with a mean diverticulum size of 68.8 ± 1.9 mm. The mean procedure time was 64.80 ± 12.6 min. with a mean septotomy/myotomy length of 79.44 ± 12.2 mm. Minor adverse events were noted intra-procedure in two cases. Clinical success achieved in all cases with a significant mean dysphagia score reduction from 2.20 to 0.20 post procedure (p = 0.011). On a median follow up of 280 days (range 98-330), none had recurrence of symptoms. Our data highlighted that complete septotomy by D-POEM technique can be achieved for the management of large esophageal diverticulum and is safe and effective.

Peroral Endoscopic Myotomy Is a Safe and Feasible Option in Management of Esophageal Diverticula: Systematic Review and Meta-Analysis

Esophageal diverticula can cause significant symptoms and affect the quality of life. There has been recent interest in the use of peroral endoscopic myotomy in the management of esophageal diverticula (D-POEM). In this meta-analysis, we have evaluated the efficacy and safety of D-POEM in the management of esophageal diverticula. Several databases were reviewed from inception to 6/19/2020 to identify the studies evaluating the feasibility, efficacy and safety of D-POEM in the management of esophageal diverticula. Our outcomes of interest were technical success, adverse events and difference in mean pre- and post-procedure symptom score. We performed subgroup analysis including patients with Zenker's diverticulum who underwent POEM (Z-POEM). Pooled rates with 95% confidence intervals (CI) for all outcomes were calculated using random effect model. We calculated standard mean difference (SMD) with 95% CI to compare mean pre- and post-procedure symptom score. We included 7 studies with 233 patients. For D-POEM, pooled rates (95% CI) for technical success and adverse events were 95% (91%, 97%) and 6% (3%, 10%) respectively. For Z-POEM, pooled rates (95% CI) for technical success and adverse events were 95% (90%, 97%) and 6% (3%, 10%) respectively. Mean post-procedure symptom score for all patients who underwent D-POEM was significantly lower compared to mean pre-procedure symptom score, SMD (95% CI) 2.17 (1.51, 2.83).  This meta-analysis demonstrated that D-POEM is a safe and feasible option for patients with symptomatic esophageal diverticula.

Per-oral Endoscopic Myotomy with Division of Septum (D-POEM) in Epiphrenic Esophageal Diverticula: Outcomes at a Median Follow-Up of Two Years

Esophageal epiphrenic diverticula (EED) are rare pulsion-type outpouchings at the lower end of esophagus. Traditionally, surgery has been performed in EED. More recently, per-oral endoscopic myotomy with septotomy (D-POEM) has emerged as an option in these cases. In this study, we aim to determine the efficacy and safety of D-POEM in cases with EED. The data of cases who underwent D-POEM in cases with EED from March 2013 to Nov 2020 were analyzed, retrospectively. The primary outcome of the study was clinical success. Secondary outcomes included technical success, procedure duration, reflux esophagitis, and adverse events. 13 patients (males 9, 48.07 ± 17.55 years) with EED underwent D-POEM during the study period. Median size of the EED was 45 mm (range 25-70). Associated esophageal motility disorder was found in 10 (76.9%) cases including type II achalasia (3), type I (3), hypercontractile esophagus (2), and unspecified (2). Technical success was achieved in 12 (92.3%) cases. Median length of total and gastric myotomies were 10 cm (range 6-20) and 3 cm (1-3), respectively. At a median follow-up of 25 months, clinical success was achieved in 84.6% cases. Mean integrated relaxation pressures reduced significantly after POEM procedure (25.80 ± 13.24 vs 9.40 ± 3.10, p = 0.001). There was one major adverse event requiring surgical intervention. D-POEM is an effective procedure in cases with EED. Long-term follow-up studies are required to ascertain the durability of response in these cases.

Diverticular per oral endoscopic myotomy (DPOEM) for esophageal diverticular disease: a systematic review and meta-analysis

The traditional way to tackle Zenker's diverticulum (ZD) has been flexible endoscopic septum division (FESD). Recently, the concept of per oral endoscopic myotomy has been found useful for managing diverticular diseases of the esophagus and has been termed DPOEM. We performed a systematic review and meta-analysis to evaluate the efficacy and safety of D-POEM in diverticular disease of the esophagus and to compare it with FESD. We systematically searched PubMed and Embase, for studies reporting clinical success, technical success and adverse events in D-POEM alone or D-POEM comparing with FESD. We computed pooled prevalence for D-POEM alone and risk ratio for D-POEM vs FESD using random effect method with inverse variance approach. Subgroup analysis for ZD, non-ZD and mixed diverticulum was conducted. Totally 19 studies including 341 patients were identified reporting on D-POEM. The pooled clinical, technical success and adverse event rates for D-POEM were 87.07%, 95.19% and 10.22%, respectively. The clinical success was significantly better than FESD while the technical success, adverse event rate, procedure time and length of hospital stay were comparable with FESD. The recurrence rate was negligible for D-POEM compared to FESD. On subgroup analysis by dividing into three groups of ZD, non-ZD and mixed, there was no difference between clinical, technical success and adverse event rate among the three groups. D-POEM is an effective and safe technique among both ZD and non-ZD patients and has better clinical success than FESD.