Same site submucosal tunneling for a repeat per oral endoscopic myotomy: A safe and feasible option

Per oral endoscopic myotomy (POEM) is a novel endoscopic procedure for achalasia treatment. Due to its novelty and high success rates, a repeat procedure is usually not warranted, making the feasibility and safety of such approach unknown. We report the first case of a successful repeat POEM done at the same site of a previously uncompleted POEM. An 84-year-old female with type 2 achalasia presented for a POEM procedure. The procedure was aborted at the end of tunneling and before myotomy due to hypotension, which later resolved spontaneously. POEM was re-attempted at the same site of the original tunnel 1 year afterward, and surprisingly we didn’t encounter any submucosal fibrosis. The procedure felt similar to a native POEM and a myotomy was performed uneventfully. Our case is the first to suggest that submucosal tunneling during a repeat POEM can be done at the same site. Hypotension during POEM is a rare complication that should be recognized as a potential result of tension capnothorax, it can however, be managed with close supportive care.     

Evolving field of third-space endoscopy: Derivatives of peroral endoscopic myotomy

Third-space endoscopy, also known as submucosal endoscopy, allows for a wide range of therapeutic interventions within the submucosal layer and even into the muscular or subserosal layers of the gastrointestinal lumen. The technical development of peroral endoscopic myotomy (POEM) for achalasia has revolutionized the field of therapeutic endoscopy and the method has been continuously refined and modified. Although POEM has been applied to treat primary achalasia, it shows a favorable clinical response in other esophageal motility disorders and as a salvage treatment after previously failed intervention. Gastroesophageal reflux after POEM has drawn considerable attention and there have been major advancements in its prevention and management. POEM has led to advantageous derivatives such as peroral endoscopic tumor resection or submucosal tunneling endoscopic resection for resection of subepithelial lesions, Zenker POEM for hypopharyngeal diverticula, diverticular POEM for epiphrenic esophageal diverticula, and gastric POEM for refractory gastroparesis. These techniques have a similar concept, which constitutes submucosal tunneling with a mucosal flap valve and secure mucosal incision closure. The submucosal tunneling technique is widely accepted and continues to evolve. This study aimed to review in detail the indications, outcomes, and technical variations in POEM and explore several emerging submucosal tunneling procedures. This review will benefit future studies by providing a summary of recent developments in this field.     

Per-oral endoscopic myotomy: Major advance in achalasia treatment and in endoscopic surgery

Per-oral endoscopic myotomy (POEM) represents a natural orifice endoscopic surgery (NOTES) approach to laparoscopy Heller myotomy (LHM). POEM is arguably the most successful clinical application of NOTES. The growth of POEM from a single center in 2008 to approximately 60 centers worldwide in 2014 with several thousand procedures having been performed attests to the success of POEM. Initial efficacy, safety and acid reflux data suggest at least equivalence of POEM to LHM, the previous gold standard for achalasia therapy. Adjunctive techniques used in the West include impedance planimetry for real-time intraprocedural luminal assessment and endoscopic suturing for challenging mucosal defect closures during POEM. The impact of POEM extends beyond the realm of esophageal motility disorders as it is rapidly popularizing endoscopic submucosal dissection in the West and spawning offshoots that use the submucosal tunnel technique for a host of new indications ranging from resection of tumors to pyloromyotomy for gastroparesis.     

Submucosal tunnel endoscopy: Peroral endoscopic myotomy and peroral endoscopic tumor resection

Peroral endoscopic myotomy(POEM) is an innovative,minimally invasive, endoscopic treatment for esophageal achalasia and other esophageal motility disorders, emerged from the natural orifice transluminal endoscopic surgery procedures, and since the first human case performed by Inoue in 2008, showed exciting results in international level, with more than 4000 cases globally up to now. POEM showed superior characteristics than the standard 100-year-old surgical or laparoscopic Heller myotomy(LHM), not only for all types of esophageal achalasia [classical(Ⅰ), vigorous(Ⅱ), spastic(Ⅲ), Chicago Classification], but also for advanced sigmoid type achalasia(S1 and S2), failed LHM, or other esophageal motility disorders(diffuse esophageal spasm, nutcracker esophagus or Jackhammer esophagus). POEM starts with a mucosal incision, followed by submucosal tunnel creation crossing the esophagogastric junction(EGJ) and myotomy. Finally the mucosal entry is closed with endoscopic clip placement. POEM permitted relatively free choice of myotomy length and localization. Although it is technically demanding procedure, POEM can be performed safely and achieves very good control of dysphagia and chest pain. Gastroesophageal reflux is the most common troublesome side effect, and is well controllable with proton pump inhibitors. Furthermore, POEM opened the era of submucosal tunnel endoscopy, with many other applications. Based on the same principles with POEM, in combination with new technological developments, such as endoscopic suturing, peroral endoscopic tumor resection(POET), is safely and effectively applied for challenging submucosal esophageal, EGJ and gastric cardia tumors(submucosal tumors), emerged from muscularis propria. POET showed up to know promising results, however, it is restricted to specialized centers. The present article reviews the recent data of POEM and POET and discussed controversial issues that need further study and future perspectives.     

经口内镜肌切开术治疗贲门失弛缓症的实验及临床经验初探

目的利用猪食管-胃模型进行经口内镜肌切开术（POEM）实验,为临床开展POEM术积累经验并探讨POEM治疗贲门失弛缓症的安全性和有效性。方法止血钳结扎离体猪的胃幽门出口,并将离体猪的食管口侧末端固定于带孔泡沫塑料,制成简易训练模型,然后以带透明帽内镜按如下步骤进行POEM术：（1）建立黏膜下隧道;（2）切断食管环形肌层;（3）封闭隧道口。经模型练习熟练掌握POEM技巧后,对4例贲门失弛缓症患者实施手术。结果5例猪食管-胃模型,2例成功完成POEM术,1例食管纵行肌层裂开穿孔,1例切断环形肌层时切除过深导致穿孔,1例于食管一胃连接部切破黏膜层。经模型练习后在临床成功开展POEM术4例,操作时间平均110min,隧道长度8—11cm,平均10．5cm,环形切断长度5～8cm,平均7cyn,术中1例出血较多,但在内镜下成功止血。食管测压提示,术后平均LES压力从术前47．07mmHg降至17．4mmHg。术后随访1～4个月,4例患者吞咽困难症状明显缓解。结论猪食管-胃模型制作简单,可作为简易的训练模型模拟POEM术过程。POEM术治疗贲门失弛缓症近期疗效肯定,远期疗效有待进一步随访。     

Peroral endoscopic myotomy: An emerging minimally invasive procedure for achalasia

Peroral endoscopic myotomy (POEM) is an emerging minimally invasive procedure for the treatment of achalasia. Due to the improvements in endoscopic technology and techniques, this procedure allows for submucosal tunneling to safely endoscopically create a myotomy across the hypertensive lower esophageal sphincter. In the hands of skilled operators and experienced centers, the most common complications of this procedure are related to insufflation and accumulation of gas in the chest and abdominal cavities with relatively low risks of devastating complications such as perforation or delayed bleeding. Several centers worldwide have demonstrated the feasibility of this procedure in not only early achalasia but also other indications such as redo myotomy, sigmoid esophagus and spastic esophagus. Short-term outcomes have showed great clinical efficacy comparable to laparoscopic Heller myotomy (LHM). Concerns related to postoperative gastroesophageal reflux remain, however several groups have demonstrated comparable clinical and objective measures of reflux to LHM. Although long-term outcomes are necessary to better understand durability of the procedure, POEM appears to be a promising new procedure.     

Consensus on the digestive endoscopic tunnel technique

With the digestive endoscopic tunnel technique(DETT), many diseases that previously would have been treated by surgery are now endoscopically curable by establishing a submucosal tunnel between the mucosa and muscularis propria(MP). Through the tunnel, endoscopic diagnosis or treatment is performed for lesions in the mucosa, in the MP, and even outside the gastrointestinal(GI) tract.At present, the tunnel technique application range covers the following:(1)Treatment of lesions originating from the mucosal layer, e.g., endoscopic submucosal tunnel dissection for oesophageal large or circular early-stage cancer or precancerosis;(2) treatment of lesions from the MP layer, per-oral endoscopic myotomy, submucosal tunnelling endoscopic resection, etc.; and(3) diagnosis and treatment of lesions outside the GI tract, such as resection of lymph nodes and benign tumour excision in the mediastinum or abdominal cavity. With the increasing number of DETTs performed worldwide, endoscopic tunnel therapeutics, which is based on DETT, has been gradually developed and optimized. However, there is not yet an expert consensus on DETT to regulate its indications, contraindications, surgical procedure, and postoperative treatment.The International DETT Alliance signed up this consensus to standardize the procedures of DETT. In this consensus, we describe the definition, mechanism,and significance of DETT, prevention of infection and concepts of DETTassociated complications, methods to establish a submucosal tunnel, and application of DETT for lesions in the mucosa, in the MP and outside the GI tract(indications and contraindications, procedures, pre-and postoperative treatments, effectiveness, complications and treatments, and a comparison between DETT and other operations).     

Submucosal tunneling endoscopic resection for simultaneous esophageal and cardia submucosal tumors originating from the muscularis propria layer (with video)

Submucosal tunneling endoscopic resection (STER) is a new treatment technique for upper gastrointestinal submucosal tumors (SMT) originating from the muscularis propria (MP) layer. In contrast to conventional endoscopic resection, the new therapy can maintain the mucosal integrity of the digestive tract, which effectively prevents mediastinitis and peritonitis. STER, although a known method, has not been widely adopted because of technical difficulties. Here, we describe the case of a 30‐year‐old patient presenting with two separate SMT originating from the esophageal and cardia MP layer. A 2‐cm longitudinal mucosal incision was made approximately 5 cm proximal to the esophageal SMT, and the esophageal and cardia SMT were dissected successively in the same submucosal tunnel. In the relevant literature, this is the first case of STER for resecting esophageal and cardia SMT using the same submucosal tunnel.     

POEM for special patient cohorts: A review

Peroral endoscopic myotomy (POEM) is a natural orifice, translumenal endoscopic surgical procedure that achieves endoscopic myotomy by conducting a submucosal tunnel as an operating space. It is conventionally performed in achalasia. Recently, several centers worldwide have reported the feasibility of this procedure not only in early achalasia but also in other particular patient cohorts. Possible indications for POEM include previously failed Heller myotomy, pneumatic balloon dilatation or POEM, sigmoid achalasia, pediatric patients, spastic esophagus disorders, Zenker’s diverticulum and gastroparesis. However, its application in large numbers of special patient groups awaits knowledge of the long‐term outcome and greater experience with POEM.     

经口内镜下肌切开术治疗贲门失弛缓症的初探

目的探讨经口内镜下肌切开术（POEM）治疗贲门失弛缓症（AC）的疗效和可行性。方法研究2010年8月至2010年12月确诊为AC并接受POEM治疗的8例患者的临床资料。患者年龄16～62岁,平均43岁,病程2-20年,平均8．4年。POEM的主要步骤包括：食管黏膜层切开;分离黏膜下层,建立黏膜下“隧道”;胃镜直视下切开环形肌;金属夹关闭黏膜层切口。结果8例患者均成功接受POEM术,手术时间45-115min,平均68．5min,黏膜下隧道长度8～13cm,平均9．5cm,环形肌切开长度7～11cm,平均8．5cm,无1例出现与POEM相关的严重并发症。术后随访1～4个月,平均2．5个月,7例吞咽困难明显得到解除;1例术后15d出现进食困难及呕吐,胃镜检查发现黏膜下窦道形成,行内镜下窦道切开。结论作为一种新的微创治疗方法,POEM治疗AC短期疗效肯定,可以迅速解除AC患者吞咽困难,但其长期疗效及远期并发症仍有待随访观察。     

内镜注水泵与注射针用于贲门失弛缓症经口内镜下肌切开术治疗的对比研究（含视频）

行黏膜下注射的效果和安全性。 方法 2013年3月至2016 年2月,中国人民解放军陆军总医院消化内科126例行POEM治疗的AC患者纳入回顾性研究,对比分析POEM治疗术中使用内镜注水泵（注水泵组,n=73）和内镜注射针（注射针组,n=73）行黏膜下注射建立隧道用时、整个手术用时以及2组并发症的发生情况。 结果 注水泵组建立10～14 cm隧道用时（6.38±0.94）min,注射针组为（13.81±1.13）min,2组间差异有统计学意义（P<0.05）。注水泵组手术用时（27.81±5.76）min,注射针组为（70.25±22.67）min,2组间差异有统计学意义（P<0.05）。注水泵组术后住院时间为（4.38±1.87）d,注射针组为（5.64±1.83）d,2组间差异有统计学意义（P<0.05）。注水泵组出血发生率[5.48%（4/73）比16.98%（9/53）]、发热发生率[12.33%（9/73）比26.42%（14/53）]均低于注射针组（P<0.05）,穿孔、胸痛发生率2组间比较差异均无统计学意义（P>0.05）。 结论 POEM治疗AC过程中使用内镜注水泵替代内镜注射针行黏膜下注射安全、有效,可以有效缩短建立黏膜下隧道用时及手术用时,同时减少出血、发热等并发症的发生。     

Peroral endoscopic myotomy

Peroral endoscopic myotomy(POEM) incorporates concepts of natural orifice translumenal endoscopic surgery and achieves endoscopic myotomy by utilizing a submucosal tunnel as an operating space. Although intended for the palliation of symptoms of achalasia, there is mounting data to suggest it is also efficacious in the management of spastic esophageal disorders. The technique requires an understanding of the pathophysiology of esophageal motility disorders as well as knowledge of surgical anatomy of the foregut. POEM achieves short term response in 82% to 100% of patients with minimal risk of adverse events. In addition, it appears to be effective and safe even at the extremes of age and regardless of prior therapy undertaken. Although infrequent, the ability of the endoscopist to manage an intraprocedural adverse event is critical as failure to do so could result in significant morbidity. The major late adverse event is gastroesophageal reflux which appears to occur in 20% to 46% of patients. Research is being conducted to clarify the optimal technique for POEM and a personalized approach by measuring intraprocedural esophagogastric junction distensibility appears promising. In addition to esophageal disorders, POEM is being studied in the management of gastroparesis(gastric pyloromyotomy) with initial reports demonstrating technical feasibility. Although POEM represents a paradigm shift the management of esophageal motility disorders, the results of prospective randomized controlled trials with long-term follow up are eagerly awaited.     

Safety and efficacy of the modified peroral endoscopic myotomy with shorter myotomy for achalasia patients: a prospective study

Peroral endoscopic myotomy (POEM) has been developed as a minimally invasive endoscopic treatment for achalasia for years. However, the optimal length of submucosal tunnel and myotomy of muscle bundles during procedure of POEM has not yet been determined, so we aim to assess safety and efficacy of modified POEM with shorter myotomy of muscle bundles in achalasia patients. Consecutive achalasia patients had been performed modified POEM with shorter myotomy, and assessed by symptoms, high‐resolution manometry, and barium swallow examinations before and 3 months after POEM for safety and efficacy evaluation. Modified POEM with shorter submucosal tunnel (mean length 6.8 cm) and endoscopic myotomy of muscle bundles (total mean length 5.4 cm) were completed in 46 consecutive achalasia patients. During the 3‐month follow up in all cases, significant improvement of symptoms (a significant drop in the Eckardt score 8.4 ± 3.2 vs. 2.7 ± 1.9; P < 0.001), decreased lower esophageal sphincter pressure (39.4 ± 10.1 vs. 24.4 ± 9.1 mmHg; P < 0.001) and integrated relaxation pressure (38.6 ± 10.4 vs. 25.7 ± 9.6 mmHg; P < 0.01), and a drop in height of esophagus barium‐contrast column (5.4 ± 3.1 vs. 2.6 ± 1.8 cm; P < 0.001) were observed. The frequencies of adverse events were lower in those under endotracheal anesthesia and CO₂ insufflations compared with intravenous anesthesia and air insufflations. Only three patients were found to have gastroesophageal reflux disease on follow up. Modified POEM with shorter myotomy under endotracheal anesthesia and CO₂ insufflations shows its good safety and excellent short‐term efficacy in the treatment of achalasia. But further studies are warranted to assess the long‐term efficacy.     

Challenges of peroral endoscopic myotomy in the treatment of distal esophageal spasm

Objective: Distal esophageal spasm (DES) is a rare motility disorder characterized by premature and rapidly propagated contractions of the distal esophagus. Treatment options are limited and often poorly effective. Peroral endoscopic myotomy (POEM) seems an effective and attractive new treatment option for DES. In this case report we describe some of the difficulties that could arise.

Materials and methods: A 84-year old man with therapy-refractory DES and complaints of severe dysphagia and chest pain underwent a POEM procedure under general anesthesia. A longer myotomy was performed to cleave the circular muscle layer from start till end of the spastic contractions.

Results: The length of the myotomy was 16?cm. Hyperactive spastic contractions during the procedure complicated the creation of the submucosal tunnel, extended the duration (134 vs. 60–90?min for achalasia), increased postoperative pain and prolonged hospital admission. Intravenously nitroglycerin peroperative diminished spastic contractions. Postoperative a remnant of spastic contractions was present, proximal to the myotomy, causing persistent symptoms.

Conclusion: Performing POEM for DES is challenging due to reactive hyperactive spastic contractions during the procedure causing technical difficulties and an extended procedure. A long myotomy, several centimeters above the proximal border of the spastic region, is essential to prevent remnants of spasticity.     

Per-oral endoscopic myotomy for achalasia: An American perspective

Achalasia is an uncommon esophageal motility disorder characterized by the selective loss of enteric neurons leading to absence of peristalsis and impaired relaxation of the lower esophageal sphincter.Per-oral endoscopic myotomy(POEM) is a novel modality for the treatment of achalasia performed by gastroenterologists and surgeons.It represents a natural orifice transluminal endoscopic surgery(NOTES) approach to Heller myotomy.POEM has the minimal invasiveness of an endoscopic procedure that can duplicate results of the surgical Heller myotomy.POEM is conceptually similar to a surgical myotomy without the inherent external incisions and post-operative care associated with surgery.Initial high success and low complications rates promise a great future for this technique.In fact,POEM has been successfully performed on patients with end-stage achalasia as an initial treatment reserving esophagectomy for those without good response.The volume of POEMs performed worldwide has grown exponentially.In fact,surgeons who have performed Heller myotomy have embraced POEM as the preferred intervention for achalasia.However,the niche of POEM remains to be defined and long term results are awaited.We describe our experience with POEM having performed the first POEM outside of Japan in 2009,the evolution of our technique,and give our perspective on its future.     

Submucosal tunneling and endoscopic resection of submucosal tumors at the esophagogastric junction

AIM: To evaluate the safety and efficacy of submucosal tunneling and endoscopic resection(STER) for treating submucosal tumors(SMTs).METHODS: Between August 2012 and October 2013, 21 patients with SMTs originating from the muscularis propria(MP) layer at the esophagogastric junction were treated by STER of their tumors. Key steps of the procedure include:(1) mucosal incision: a 2-cm longitudinal mucosal incision was made 5 cm proximal to the tumor;(2) submucosal tunneling: a submucosal tunnel was created 5 cm proximal to and 1 to 2 cm distal to the tumor;(3) tumor resection: the SMT was resected under direct endoscopic viewing;(4) hemostasis: while finishing the tumor resection, careful hemostasis of the MP defect and the tunnel was performed; and(5) mucosal closure: the mucosal incision site was closed by using hemostatic clips. During the operation, equipment used included a cap-fitted endoscope, an insulatedtip knife, a hook knife, hemostatic forceps, an injection needle, a snare, an endoclip, and a high-frequency generator. Carbon dioxide(CO2) insufflation was achieved by using a CO2 insufflator.RESULTS: The median age of the patients was 46.2 years(range, 35-59 years), and the majority were male(18 male vs 3 female). Complete resection rate was 100%(21/21). Eighteen lesions were resected en bloc. Mean tumor size was 23 mm(range, 10-40 mm), and mean procedure time was 62.9 min(range, 45-90 min). Pathological diagnosis of these tumors included leiomyoma(15 out of 21) and gastrointestinal stromal tumor(6 out of 21). Full-thickness MP resection was performed in 9 of 21 patients(42.9%), with mediastinal and subcutaneous emphysema occurring in all nine. At the completion of the procedure, all patients received closure of the incision with hemoclips. One patient required percutaneous drainage. The remaining 20patients required no further endoscopic or surgical intervention. There were no incidents of massive or delayed bleeding. The median follow-up period after the procedure was 6 mo(range, 2-14 mo). During followup, no patients were found to have residual or recurrent tumor or esophageal stricture.CONCLUSION: STER is safe, effective and feasible, which provides accurate histopathologic evaluation and curative treatment for SMTs originating from the MP layer at the esophagogastric junction.     

Peroral endoscopic myotomy for esophageal achalasia: Indication and technique

Since the inception of peroral endoscopic myotomy (POEM) in 2008, more than 2000 POEMs have been performed to date in the world. The technique has been standardized to include the following 5 steps: mucosectomy, submucosal tunnel creation, esophageal myotomy, cardiomyotomy, and mucosectomy closure. Minor technique variations do exist as far as the equipment utilized as well as with the orientation and completeness of the myotomy. This article describes the equipment used during POEM as well as the essential steps to have a safe and successful procedure.     

Therapeutic flexible endoscopy replacing surgery: Part 3—Peroral esophageal myotomy

Peroral esophageal myotomy (POEM) is a novel endoscopic operation for achalasia, first performed clinically by Haru Inoue in Japan in 2008. Using techniques developed through experience in endoscopic submucosal dissection and natural orifice transluminal endoscopic surgery, during the POEM procedure a controlled surgical myotomy across the esophagogastric junction is created using a standard flexible gastroscope, thus eliminating all skin incisions. This article reviews the key steps of the procedure, and outlines the necessary skills, equipment, and instrumentation that are required to perform it. The existing literature regarding procedural and postoperative outcomes is reviewed, and recommendations are given regarding the symptomatic and physiological assessment of POEM patients going forward, so that the procedure can be objectively compared with the current standard of care, laparoscopic Heller myotomy.     

Recent advancement of therapeutic endoscopy in the esophageal benign diseases

Over the past 30 years, the field of endoscopy has witnessed several advances. With the advent of endoscopic mucosal resection, removal of large mucosal lesions have become possible. Thereafter, endoscopic submucosal resection was refined, permitting en bloc removal of large superficial neoplasms. Such techniques have facilitated the development of antireflux mucosectomy, a promising novel treatment for gastroesophageal reflux. The introduction and use of over the scope clips has allowed for endoscopic closure of defects in the gastrointestinal tract, which were traditionally treated with surgical intervention. With the development of per-oral endoscopic myotomy(POEM), the treatment of achalasia and spastic disorders of the esophagus have been revolutionized. From the submucosal tunnelling technique developed for POEM, Per oral endoscopic tumor resection of subepithelial tumors was made possible. Simultaneously, advances in biotechnology have expanded esophageal stenting capabilities with the introduction of fully covered metal and plastic stents, as well as biodegradable stents. Once deemed a primarily diagnostic tool, endoscopy has quickly transcended to a minimally invasive intervention and therapeutic tool. These techniques are reviewed with regards to their application to benign disease of the esophagus.     

Recent advances in third space or intramural endoscopy

Third space endoscopy or intramural endoscopy is based on the principle that the deeper layers of the gastrointestinal tract can be accessed by tunneling in the submucosal space and maintaining the integrity of the overlying mucosa. The era of third space endoscopy started with peroral endoscopic myotomy (POEM) for treatment of achalasia and has expanded to treat various other gastrointestinal disorders. The technique is also currently used for treatment of refractory gastroparesis, Zenker’s diverticulum (ZD), resection of subepithelial tumors and early cancers of the gastrointestinal tract and Hirschsprung’s disease (HD). These procedures are rapidly emerging as minimally invasive alternatives to conventional surgery. They are safe and effective with excellent outcomes. This review focuses on the evolution and current applications of third space endoscopy in various gastrointestinal disorders. Key points: (1) Third space or intramural endoscopy initially started with the POEM procedure for treatment of achalasia; (2) Advancements in procedural techniques have expanded its application to treat other gastrointestinal disorders such as refractory gastroparesis, ZD, HD, resection of subepithelial tumors and early gastrointestinal cancers; (3) These procedures are highly effective with excellent outcomes and low complication rates; and (4) Third space endoscopic procedures are rapidly emerging as minimally invasive alternatives to conventional surgery.