Endoscopic submucosal myotomy for the treatment of achalasia (with video)

Is peroral endoscopic myotomy the new gold standard for achalasia therapy?

Our review focuses on critical analysis of the literature to determine whether peroral endoscopic myotomy (POEM) is poised to replace laparoscopic Heller myotomy (LHM) as the new "gold standard" for achalasia therapy. POEM matches or exceeds the efficacy of LHM. The difference in objective gastroesophageal reflux disease (GERD) between POEM and LHM is modest at best and dissipates with time. Post-POEM GERD can be easily managed medically in most patients without long-term GERD sequelae or the need for surgical fundoplication. Emerging POEM technique modifications can further decrease GERD. Endoscopic antireflux procedures such as transoral incisionless fundoplication (TIF) or POEM + F (POEM + fundoplication) can be used in the rare cases of medication-refractory GERD, but their long-term efficacy remains in question. In this comprehensive review, we summarize the current status of POEM with emphasis on GERD evaluation, prevention, treatment, and comparative data vs. LHM. Based on this analysis, it appears that POEM is indeed the new gold standard in the therapy of achalasia.

Peroral endoscopic myotomy: 10-year outcomes from a large, single-center U.S. series with high follow-up completion and comprehensive analysis of long-term efficacy, safety, objective GERD, and endoscopic functional luminal assessment

BACKGROUND AND AIMS

Peroral endoscopic myotomy (POEM) is becoming the treatment of choice for achalasia. Data beyond 3 years are emerging but are limited. We herein report our 10-year experience, focusing on long-term efficacy and safety including the prevalence, management, and sequelae of postoperative reflux.

METHODS

This was a single-center prospective cohort study.

RESULTS

Six hundred ten consecutive patients received POEM from October 2009 to October 2019, 160 for type 1 achalasia (26.2%), 307 for type II (50.3%), 93 for type III (15.6%), 25 for untyped achalasia (4.1%), and 23 for nonachalasia disorders (3.8%). Two hundred ninety-two patients (47.9%) had prior treatment(s). There was no aborted POEM. Median operation time was 54 minutes. Accidental mucosotomies occurred in 64 patients (10.5%) and clinically significant adverse events in 21 patients (3.4%). No adverse events led to death, surgery, interventional radiology interventions/drains, or altered functional status. At a median follow-up of 30 months, 29 failures occurred, defined as postoperative Eckardt score >3 or need for additional treatment. The Kaplan-Meier clinical success estimates at years 1, 2, 3, 4, 5, 6, and 7 were 98%, 96%, 96%, 94%, 92%, 91%, and 91%, respectively. These are highly accurate estimates because only 13 patients (2%) were missing follow-up assessments. One hundred twenty-five patients (20.5%) had reflux symptoms more than once per week. At a median of 4 months, the pH study was completed in 406 patients (66.6%) and was positive in 232 (57.1%), and endoscopy was completed in 438 patients (71.8%) and showed reflux esophagitis in 218 (49.8%), mostly mild.

CONCLUSIONS

POEM is exceptionally safe and highly effective on long-term follow-up, with >90% clinical success at ≥5 years.

Learning Curve for Endoscopic Submucosal Dissection With an Untutored, Prevalence-Based Approach in the United States

BACKGROUND & AIMS

Endoscopic submucosal dissection (ESD) is widely used in Asia to resect early-stage gastrointestinal neoplasms, but use of ESD in Western countries is limited. We collected data on the learning curve for ESD at a high-volume referral center in the United States to guide development of training programs in the Americas and Europe.

METHODS

We performed a retrospective analysis of consecutive ESDs performed by a single operator at a high-volume referral center in the United States from 2009 through 2017. ESD was performed in 540 lesions: 449 mucosal (10% esophageal, 13% gastric, 5% duodenal, 62% colonic, and 10% rectal) and 91 submucosal. We estimated case volumes required to achieve accepted proficiency benchmarks (>90% for en bloc resection and >80% for histologic margin-negative (R0) resection) and resection speeds >9cm²/hr.

RESULTS

Pathology analysis of mucosal lesions identified 95 carcinomas, 346 premalignant lesions, and 8 others; the rate of en bloc resection increased from 76% in block 1 (50 cases) to a plateau of 98% after block 5 (250 cases). The rate of R0 resection improved from 45% in block 1 to >80% after block 5 (250 cases) and ∼95% after block 8 (400 cases). Based on cumulative sum analysis, approximately 170, 150, and 280 ESDs are required to consistently achieve a resection speed >9cm²/hr in esophagus, stomach, and colon, respectively.

CONCLUSIONS

In an analysis of ESDs performed at a large referral center in the United States, we found that an untutored, prevalence-based approach allowed operators to achieve all proficiency benchmarks after ∼250 cases. Compared with Asia, ESD requires more time to learn in the West, where the untutored, prevalence-based approach requires resection of challenging lesions, such as colon lesions and previously manipulated lesions, in early stages of training.

Bridging the Gap between Advancements in the Evolution of Diagnosis and Treatment towards Better Outcomes in Achalasia

Over the past few decades, there was an encouraging breakthrough in bridging the gap between advancements in the evolution of diagnosis and treatment towards a better outcome in achalasia. The purpose of this review is to provide updated knowledge on how the current evidence has bridged the gap between advancements in the evolution of diagnosis and treatment of esophageal achalasia. The advent of high-resolution manometry and standardization based on the Chicago classification has increased early recognition of the disease. These 3 clinical subtypes of achalasia can predict the outcomes of patients, and the introduction of POEM has revolutionized the choice of treatment. Previous evidence has shown that laparoscopic Heller myotomy (LHM) and anterior fundoplication were considered the most durable treatments for achalasia. Based on the current evidence, POEM has been evolving as a promising strategy and is effective against all 3 types of achalasia, but the efficacy of POEM is based on short- and medium-term outcome studies from a limited number of centers. Types I and II achalasia respond well to POEM, LHM, and PD, while most studies have shown that type III achalasia responds better to POEM than to LHM and PD. In general, among the 3 subtypes of achalasia, type II achalasia has the most favorable outcomes after medical or surgical therapies. The long-term efficacy of POEM is still unknown. The novel ENDOFLIP measures the changes in intraoperative esophagogastric junction dispensability, which enables a quantitative assessment of luminal patency and sphincter distension; however, this technology is in its infancy with little data to date supporting its intraoperative use. In the future, identifying immunomodulatory drugs and the advent of stem cell therapeutic treatments, including theoretically transplanting neuronal stem cells, may achieve a functional cure. In summary, it is important to identify the clinical subtype of achalasia to initiate target therapy for these patients.

Treatment of Idiopathic Achalasia with Per-Oral Esophageal Myotomy

Achalasia is a rare esophageal motility disorder that necessitates the disruption of the lower esophageal sphincter. Patients with achalasia should be evaluated in a systematic, multidisciplinary fashion. Workup should include upper endoscopy, esophagography, and high-resolution manometry. The gold standard for surgical treatment is laparoscopic Heller myotomy with partial fundoplication. Per-oral esophageal myotomy is a novel endoscopic technique that has gained considerable traction over the past decade. The procedure includes the creation of a submucosal tunnel and a selective circular myotomy of the lower esophageal sphincter. Common intra-operative hazards include bleeding within the submucosal tunnel and capnoperitoneum. Significant complications are rare. Patients experience excellent dysphagia relief that is on par with laparoscopic Heller myotomy at moderate-term follow up. Post-operative gastroesophageal reflux disease occurs in greater than one-third of patients, and the vast majority of cases are readily controlled with an anti-secretory medication. Although data is sparse, there is a growing body of literature that supports the long-term durability of per-oral esophageal myotomy.

Per-oral endoscopic myotomy in patients with or without prior Heller's myotomy: comparing long-term outcomes in a large U.S. single-center cohort (with videos)

BACKGROUND AND AIMS

Heller's myotomy (HM) is one of the most effective treatments for esophageal achalasia. However, failures do exist, and the success rate tends to decrease with time. The efficacy of rescue treatments for patients with failed HM is limited. A few small-scale studies have reported outcomes of per-oral endoscopic myotomy (POEM) in these patients. We conducted this study to systematically assess feasibility, safety, and efficacy of POEM on patients who have had HM.

METHODS

Patients at least 3 months out from POEM were selected from our prospective database: 318 consecutive POEMs performed from October 2009 to October 2016. The efficacy and safety of POEM were compared between the 46 patients with prior HM and the remaining 272 patients.

RESULTS

Patients with prior HM had longer disease history, more advanced disease, more type I and less type II achalasia, lower before-POEM Eckardt scores, and lower before-POEM lower esophageal sphincter (LES) pressure (all P < .01). Procedure parameters and follow-up results (clinical success rate, Eckardt score, LES pressure, GERD score, esophagitis, and pH testing) showed no significant difference between the 2 groups. For the 46 HM-POEM patients, no clinically significant perioperative adverse events occurred. Their overall clinical success rate (Eckardt score ≤3 and no other treatment needed) was 95.7% at a median follow-up of 28 months.

CONCLUSION

POEM as a rescue treatment for patients with achalasia who failed HM is feasible, safe, and highly effective. It should be the treatment of choice in managing these challenging cases at centers with a high level of experience with POEM.

The current state of per oral endoscopic myotomy for achalasia

Achalasia is an acquired neuromuscular disorder that has been treated using a variety of modalities throughout medical history. Recently, the technique of per oral endoscopic myotomy (POEM) was introduced to treat the disease using a truly minimally invasive, natural orifice technique that is rapidly being adopted across the world. This review outlines the development of POEM, the technique itself, and gives a comparison to other procedures, specifically laparoscopic Heller myotomy (LHM).

Comparison of conventional versus Hybrid knife peroral endoscopic myotomy methods for esophageal achalasia: a case-control study

OBJECTIVE

Peroral endoscopic myotomy (POEM) has been developed to treat achalasia as a novel less invasive modality. We aimed to compare the efficacy and safety of conventional knife versus Hybrid knife (HK) during POEM procedure.

MATERIALS AND METHODS

Between June 2012 and July 2014, 31 patients underwent POEM using HK in our department (HK group), and 36 patients underwent POEM using conventional method (injection needle and triangular tip [TT] knife, TT group). Procedure-related parameters, symptom relief, adverse events were compared between two groups.

RESULTS

There were no significant differences in the age, sex and other baseline characteristics between the two groups. The mean procedural time was significantly shorter in HK group than TT group (53.0 ± 17.2 vs. 67.6 ± 28.4 min, p = 0.015). The mean frequency of devices exchange was 4.7 ± 1.7 in HK group and 10.9 ± 1.8 in TT group (p = 0.000). No serious adverse events occurred postoperatively in both groups. At one-year follow-up, a total of 94% treatment success was achieved in all patients (93.5% in HK group and 94.4% in TT group, p = 0.877).

CONCLUSION

HK in POEM can shorten the procedural time, and achieve similar treatment success compared to conventional TT knife.

A Western Perspective on "New NOTES" from POEM to Full-thickness Resection and Beyond

Most new natural orifice translumenal endoscopic surgery procedures originated in Asia; therefore, most data come from operators and a health care environment different from those in the West. We provide a Western perspective. We discuss East-West differences; review areas in which the United States is leading the way; and discuss the vagaries of coding and reimbursement. In the United States, reimbursement remains problematic. A Current Procedural Terminology code for peroral endoscopic myotomy is inevitable given the rapidly accumulating overwhelmingly positive outcomes data. However, coordinated efforts may help accelerate the process.

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.

The light at the end of the tunnel: a single-operator learning curve analysis for per oral endoscopic myotomy

BACKGROUND

Per oral endoscopic myotomy (POEM) represents a natural orifice transluminal endoscopic surgery approach to Heller myotomy. Our center was the first to offer POEM outside of Japan, allowing us to accumulate what is likely the highest single-operator POEM volume in the United States.

OBJECTIVE

To define the POEM learning curve of a gastroenterologist by using a larger data set and more detailed statistical analysis than used in 2 other reports of POEM performed by surgeons.

DESIGN

Prospective cohort study.

SETTING

Tertiary-care academic medical center.

PATIENTS

We analyzed the first 93 consecutive POEMs on patients with achalasia aged >18 years without contraindications to POEM performed by a single operator from October 2009 to November 2013.

INTERVENTIONS

(1) Efficiency estimation via cumulative sum (CUSUM) analysis, (2) mastery estimation via penalized basis-spline regression and CUSUM analysis, (3) correlation of operator experience with clinical outcomes (Eckardt score improvement, lower esophageal sphincter pressure reduction) and technical errors (accidental mucosotomy rate), and (4) unadjusted and adjusted regression analysis to assess how patient characteristics affected procedure time by using a generalized linear model.

MAIN OUTCOME MEASUREMENTS

Clinical outcomes, procedure time, technical errors.

RESULTS

Efficiency was attained after 40 POEMs and mastery after 60 POEMs. When we used the adjusted regression analysis, only case number (operator experience) significantly affected procedure time (P < .0001). Improvements in clinical outcomes were excellent but not significantly affected by operator experience, as was the case with accidental mucosotomies. Procedure time was not significantly affected by age, sex, achalasia stage, baseline lower esophageal sphincter pressure, baseline Eckardt score, prior treatment of achalasia, prior botulinum toxin injection, incidence of accidental mucosotomies, length of myotomy, or type of knife used (all P > .05).

LIMITATIONS

Our analysis may underestimate the number of POEMs required to achieve mastery for operators with limited or no endoscopic submucosal dissection experience.

CONCLUSION

These results offer thresholds for efficiency and mastery of a single gastroenterologist operator that may guide the efforts of novice POEM operators.

Peroral endoscopic myotomy for treatment of achalasia

Achalasia is a motility disorder of the esophagus, characterized by aperistalsis of the esophageal body and incomplete relaxation of the lower esophageal sphincter (LES). Peroral endoscopic myotomy (POEM) is an emerging novel endoscopic procedure for the treatment of achalasia by incision of LES via a submucosal tunnel. On the basis of initial data suggesting an acceptable safety profile and excellent short-term symptom resolution, there is growing enthusiasm in favor of POEM. In this review we outline the technical aspects of POEM, summarize the available data on safety and outcomes, and suggest future directions for further advancement of this minimally invasive approach for the treatment of achalasia.

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.

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.

Current status in the treatment options for esophageal achalasia

Recent advances in the treatment of achalasia include the use of high-resolution manometry to predict the outcome of patients and the introduction of peroral endoscopic myotomy (POEM). The first multicenter randomized, controlled, 2-year follow-up study conducted by the European Achalasia Trial group indicated that laparoscopic Heller myotomy (LHM) was not superior to pneumatic dilations (PD). Publications on the long-term success of laparoscopic surgery continue to emerge. In addition, laparoscopic single-site surgery is applicable to advanced laparoscopic operations such as LHM and anterior fundoplication. The optimal treatment option is an ongoing matter of debate. In this review, we provide an update of the current progress in the treatment of esophageal achalasia. Unless new conclusive data prove otherwise, LHM is considered the most durable treatment for achalasia at the expense of increased reflux-associated complications. However, PD is the first choice for non-surgical treatment and is more cost-effective. Repeated PD according to an “on-demand” strategy based on symptom recurrence can achieve long-term remission. Decision making should be based on clinical evidence that identifies a subcategory of patients who would benefit from specific treatment options. POEM has shown promise but its long-term efficacy and safety need to be assessed further.

Endoscopic approach to achalasia

Achalasia is a primary esophageal motor disorder. The etiology is still unknown and therefore all treatment options are strictly palliative with the intention to weaken the lower esophageal sphincter (LES). Current established endoscopic therapeutic options include pneumatic dilation (PD) or botulinum toxin injection. Both treatment approaches have an excellent symptomatic short term effect, and lead to a reduction of LES pressure. However, the long term success of botulinum toxin (BT) injection is poor with symptom recurrence in more than 50% of the patients after 12 mo and in nearly 100% of the patients after 24 mo, which commonly requires repeat injections. In contrast, after a single PD 40%-60% of the patients remain asymptomatic for ≥ 10 years. Repeated on demand PD might become necessary and long term remission can be achieved with this approach in up to 90% of these patients. The main positive predictors for a symptomatic response to PD are an age > 40 years, a LES-pressure reduction to < 15 mmHg and/or an improved radiological esophageal clearance post-PD. However PD has a significant risk for esophageal perforation, which occurs in about 2%-3% of cases. In randomized, controlled studies BT injection was inferior to PD and surgical cardiomyotomy, whereas the efficacy of PD, in patients > 40 years, was nearly equivalent to surgery. A new promising technique might be peroral endoscopic myotomy, although long term results are needed and practicability as well as safety issues must be considered. Treatment with a temporary self expanding stent has been reported with favorable outcomes, but the data are all from one study group and must be confirmed by others before definite recommendations can be made. In addition to its use as a therapeutic tool, endoscopy also plays an important role in the diagnosis and surveillance of patients with achalasia.

The International Per Oral Endoscopic Myotomy Survey (IPOEMS): a snapshot of the global POEM experience

BACKGROUND

Per oral endoscopic myotomy (POEM) represents a Natural Orifice Transluminal Endoscopic Surgery (NOTES) approach to Heller myotomy. Even though we are now entering an exponential phase of growth with a large number of centers interested in POEM, published data to guide them are limited. As part of the July 2012 NOSCAR meeting, a conference was organized to review POEM and develop a consensus document. Authors SNS and TS who chaired the NOSCAR panel recognized the dearth of published data, which also may lag the rapid developments in POEM. Therefore, they undertook a survey of early POEM adopters around the world to rapidly obtain global, extensive, and current data on POEM. The raw survey data were made available to NOSCAR panel participants to assist with their presentations. We summarize the salient findings of the survey.

METHODS

A comprehensive POEM survey was created and tested. The final survey instrument consisted of 197 questions that covered all aspects of POEM, including operator discipline, prior training, patient selection, setting, technique preference, results, adverse events, regulatory requirements, and perspectives on the future. An automated online response collector was used.

RESULTS

The International Per Oral Endoscopic Myotomy Survey (IPOEMS) involved 16 expert centers, 7 in North America, 5 in Asia, 4 in Europe, including all high-volume centers (≥30 POEMs per center), as of July 2012. These centers had performed 841 POEMs. There were modest variations among centers in technique and periprocedural management, but all centers uniformly reported excellent efficacy and safety outcomes.

CONCLUSIONS

The international POEM survey provides a "global snapshot" of the experience of early adopters. The excellent outcomes over a large cumulative volume of procedures are in line with those of published small series and lend further support to the notion that POEM represents a paradigm shift in the treatment of achalasia.

The International Per Oral Endoscopic Myotomy Survey (IPOEMS): a snapshot of the global POEM experience

BACKGROUND

Per oral endoscopic myotomy (POEM) represents a Natural Orifice Transluminal Endoscopic Surgery (NOTES) approach to Heller myotomy. Even though we are now entering an exponential phase of growth with a large number of centers interested in POEM, published data to guide them are limited. As part of the July 2012 NOSCAR meeting, a conference was organized to review POEM and develop a consensus document. Authors SNS and TS who chaired the NOSCAR panel recognized the dearth of published data, which also may lag the rapid developments in POEM. Therefore, they undertook a survey of early POEM adopters around the world to rapidly obtain global, extensive, and current data on POEM. The raw survey data were made available to NOSCAR panel participants to assist with their presentations. We summarize the salient findings of the survey.

METHODS

A comprehensive POEM survey was created and tested. The final survey instrument consisted of 197 questions that covered all aspects of POEM, including operator discipline, prior training, patient selection, setting, technique preference, results, adverse events, regulatory requirements, and perspectives on the future. An automated online response collector was used.

RESULTS

The International Per Oral Endoscopic Myotomy Survey (IPOEMS) involved 16 expert centers, 7 in North America, 5 in Asia, 4 in Europe, including all high-volume centers (≥30 POEMs per center), as of July 2012. These centers had performed 841 POEMs. There were modest variations among centers in technique and periprocedural management, but all centers uniformly reported excellent efficacy and safety outcomes.

CONCLUSIONS

The international POEM survey provides a "global snapshot" of the experience of early adopters. The excellent outcomes over a large cumulative volume of procedures are in line with those of published small series and lend further support to the notion that POEM represents a paradigm shift in the treatment of achalasia.

Endoscopic approaches to treatment of achalasia

Endoscopic therapy for achalasia is directed at disrupting or weakening the lower esophageal sphincter (LES). The two most commonly utilized endoscopic interventions are large balloon pneumatic dilation (PD) and botulinum toxin injection (BTI). These interventions have been extensively scrutinized and compared with each other as well as with surgical disruption (myotomy) of the LES. PD is generally more effective in improving dysphagia in achalasia than BTI, with the latter reserved for infirm older people, and PD may approach treatment results attained with myotomy. However, PD may need to be repeated. Small balloon dilation and endoscopic stent placement for achalasia have only been used in select centers. Per oral endoscopic myotomy is a newer endoscopic modality that will likely change the treatment paradigm for achalasia. It arose from the field of natural orifice transluminal endoscopic surgery and represents a scarless endoscopic approach to Heller myotomy. This is a technique that requires extensive training and preparation and thus there should be rigorous accreditation and monitoring of outcomes to ensure safety and efficacy.

New endoscopic classification of achalasia for selection of candidates for peroral endoscopic myotomy

AIM: To propose a new endoscopic classification of achalasia for selecting patients appropriate for undergoing peroral endoscopic myotomy (POEM).

METHODS: We screened out the data of patients with achalasia examined from October 2000 to September 2011 at our Digestive Endoscopic Center with endoscopic pictures clear enough to reveal the morphology of middle and lower esophagus. After analyzing the correlation between the endoscopic morphology of the esophageal lumen and POEM, we proposed a new endoscopic classification (Ling classification) of achalasia according to three kinds of endoscopically viewed structures: multi-ring structure, crescent-like structure and diverticulum structure. There were three types based on the criteria of Ling classification: type I, smooth without multi-ring, crescent-like structure or diverticulum structure; type II, with multi-ring or crescent-like structure but without diverticulum structure; and type III, with diverticulum structure. Type II was classified into three subtypes: Ling II_a, Ling II_b and Ling II_c; and type III also had three subtypes: Ling III_l, Ling III_r and Ling III_lr. Two endoscopists made a final decision upon mutual agreement through discussion if their separately recorded characteristics were different.

RESULTS: Among the 976 screened patients with achalasia, 636 patients with qualified endoscopic pictures were selected for the analysis, including 405 males and 231 females. The average age was 42.7 years, ranging from 6 to 93 years. Type I was the most commonly observed type of achalasia, accounting for 64.5% (410/636), and type III was the least commonly observed type of achalasia, accounting for 2.8% (18/636). And type II accounted for 32.7% (208/636) and subtype of Ling II_a, Ling II_b and Ling II_c accounted for 14.6% (93/636), 9.9% (63/636) and 8.2% (52/636), respectively. And subtype of Ling III_l, Ling III_r and Ling III_lr accounted for 0.8% (5/636), 0.3% (2/636) and 1.7% (11/636), respectively.

CONCLUSION: A new endoscopic classification of achalasia is proposed that might help in determining the proper candidates for POEM.

Achalasia

Endoscopic therapy for achalasia is centered on disrupting or weakening the lower esophageal sphincter. The three traditional treatment options for achalasia are surgical myotomy, pneumatic dilation, and botulinum toxin injection. Pneumatic dilation yields results that are generally better than botulinum toxin injection and may approach a clinical response comparable with surgery. Per oral endoscopic myotomy is a newer endoscopic modality that will likely change the treatment paradigm for achalasia.

Endoscopic full-thickness biopsy of the gastric wall with defect closure by using an endoscopic suturing device: survival porcine study

BACKGROUND

The pathogenesis of several common gastric motility diseases and functional GI disorders remains essentially unexplained. Gastric wall biopsies that include the muscularis propria to evaluate the enteric nervous system, interstitial cells of Cajal, and immune cells can provide important insights for our understanding of the etiology of these disorders.

OBJECTIVES

To determine the technical feasibility, reproducibility, and safety of performing a full-thickness gastric biopsy (FTGB) by using a submucosal endoscopy with mucosal flap (SEMF) technique; the technical feasibility, reproducibility, and safety of tissue closure by using an endoscopic suturing device; the ability to identify myenteric ganglia in resected specimens; and the long-term safety.

DESIGN

Single center, preclinical survival study.

SETTING

Animal research laboratory, developmental endoscopy unit.

SUBJECTS

Twelve domestic pigs.

INTERVENTIONS

Animals underwent an SEMF procedure with gastric muscularis propria resection. The resultant offset mucosal entry site was closed by using an endoscopic suturing device. Animals were kept alive for 2 weeks.

MAIN OUTCOME MEASUREMENTS

The technical feasibility, reproducibility, and safety of the procedure; the clinical course of the animals; the histological and immunochemical evaluation of the resected specimen to determine whether myenteric ganglia were present in the sample.

RESULTS

FTGB was performed by using the SEMF technique in all 12 animals. The offset mucosal entry site was successfully closed by using the suturing device in all animals. The mean resected tissue specimen size was 11 mm. Mean total procedure time was 61 minutes with 2 to 4 interrupted sutures placed per animal. Histology showed muscularis propria and serosa, confirming full-thickness resections in all animals. Myenteric ganglia were visualized in 11 of 12 animals. The clinical course was uneventful. Repeat endoscopy and necropsy at 2 weeks showed absence of ulceration at both the mucosal entry sites and overlying the more distal muscularis propria resection sites. There was complete healing of the serosa in all animals with minimal single-band adhesions in 5 of 12 animals. Retained sutures were present in 10 of 12 animals.

LIMITATIONS

Animal experiment.

CONCLUSIONS

FTGB by using the SEMF technique and an endoscopic suturing device is technically feasible, reproducible, and safe. Larger tissue specimens will allow improved analysis of multiple cell types.

Intraoperative assessment of esophagogastric junction distensibility during per oral endoscopic myotomy (POEM) for esophageal motility disorders

BACKGROUND

Per oral endoscopic myotomy (POEM) is a novel treatment for esophageal motility disorders such as achalasia. To date, the extent of the myotomy has been determined based on the subjective assessment of the endoscopist. We hypothesized that the real-time measurement of esophagogastric junction (EGJ) distensibility using a novel functional lumen-imaging probe would enable objective evaluation of POEM.

METHODS

Patients diagnosed with achalasia disorders electively underwent POEM. Using impedance planimetry with a transorally inserted functional lumen-imaging probe (EndoFLIP), cross-sectional areas (CSA) and distensibilities at the EGJ were measured intraoperatively immediately before and after the transoral myotomy (n = 4). All patients completed their 6-month follow-up and two patients had repeat distensibility tests at this time. Four healthy volunteers served as a control group.

RESULTS

POEM was successfully performed in all patients (4/4). Premyotomy measurements (40-ml fill mode) showed a median diameter of 6.5 mm (range = 5.2-7.9 mm) at the narrowest location of the EGJ and was 10.1 mm (7.3-13.2 mm) following POEM. CSA increased from 41.5 mm(2) (20-49 mm(2)) to 86 mm(2) (41-137 mm(2)) at a similar median intraballoon pressure (40.3 vs. 38.6 mmHg). The increased EGJ distensibility (DI, 1.0 vs. 2.4 mm(2)/mmHg) was comparable to that of healthy volunteers (2.7 mm(2)/mmHg).

CONCLUSION

Functional lumen distensibility measures show that POEM can result in an immediate correction of the nonrelaxing lower esophageal sphincter, which appears similar to that of healthy controls. Intraoperative EGJ profiling may be an important tool to objectively guide the needed extent and completeness of the myotomy during POEM.

Intraoperative assessment of esophagogastric junction distensibility during per oral endoscopic myotomy (POEM) for esophageal motility disorders

BACKGROUND

Per oral endoscopic myotomy (POEM) is a novel treatment for esophageal motility disorders such as achalasia. To date, the extent of the myotomy has been determined based on the subjective assessment of the endoscopist. We hypothesized that the real-time measurement of esophagogastric junction (EGJ) distensibility using a novel functional lumen-imaging probe would enable objective evaluation of POEM.

METHODS

Patients diagnosed with achalasia disorders electively underwent POEM. Using impedance planimetry with a transorally inserted functional lumen-imaging probe (EndoFLIP), cross-sectional areas (CSA) and distensibilities at the EGJ were measured intraoperatively immediately before and after the transoral myotomy (n = 4). All patients completed their 6-month follow-up and two patients had repeat distensibility tests at this time. Four healthy volunteers served as a control group.

RESULTS

POEM was successfully performed in all patients (4/4). Premyotomy measurements (40-ml fill mode) showed a median diameter of 6.5 mm (range = 5.2-7.9 mm) at the narrowest location of the EGJ and was 10.1 mm (7.3-13.2 mm) following POEM. CSA increased from 41.5 mm(2) (20-49 mm(2)) to 86 mm(2) (41-137 mm(2)) at a similar median intraballoon pressure (40.3 vs. 38.6 mmHg). The increased EGJ distensibility (DI, 1.0 vs. 2.4 mm(2)/mmHg) was comparable to that of healthy volunteers (2.7 mm(2)/mmHg).

CONCLUSION

Functional lumen distensibility measures show that POEM can result in an immediate correction of the nonrelaxing lower esophageal sphincter, which appears similar to that of healthy controls. Intraoperative EGJ profiling may be an important tool to objectively guide the needed extent and completeness of the myotomy during POEM.

Peroral Endoscopic Myotomy for Esophageal Achalasia by HybridKnife: A Case Report

This paper presented a case of esophageal achalasia treated by peroral endoscopic myotomy with HybridKnife and discuss the feasibility and the possible advantages of using it.

Peroral Endoscopic Myotomy for Esophageal Achalasia by HybridKnife: A Case Report

This paper presented a case of esophageal achalasia treated by peroral endoscopic myotomy with HybridKnife and discuss the feasibility and the possible advantages of using it.

A technical review of flexible endoscopic multitasking platforms

BACKGROUND

Further development of advanced therapeutic endoscopic techniques and natural orifice translumenal endoscopic surgery (NOTES) requires a powerful flexible endoscopic multitasking platform.

METHODS

Medline search was performed to identify literature relating to flexible endoscopic multitasking platform from year 2004-2011 using keywords: Flexible endoscopic multitasking platform, NOTES, Instrumentation, Endoscopic robotic surgery, and specific names of various endoscopic multitasking platforms. Key articles from articles references were reviewed.

RESULTS

Flexible multitasking platforms can be classified as either mechanical or robotic. Purely mechanical systems include the dual channel endoscope (DCE) (Olympus), R-Scope (Olympus), the EndoSamurai (Olympus), the ANUBIScope (Karl-Storz), Incisionless Operating Platform (IOP) (USGI), and DDES system (Boston Scientific). Robotic systems include the MASTER system (Nanyang University, Singapore) and the Viacath (Hansen Medical). The DCE, the R-Scope, the EndoSamurai and the ANUBIScope have integrated visual function and instrument manipulation function. The IOP and DDES systems rely on the conventional flexible endoscope for visualization, and instrument manipulation is integrated through the use of a flexible, often lockable, multichannel access device. The advantage of the access device concept is that it allows optics and instrument dissociation. Due to the anatomical constrains of the pharynx, systems are designed to have a diameter of less than 20 mm. All systems are controlled by traction cable system actuated either by hand or by robotic machinery. In a flexible system, this method of actuation inevitably leads to significant hysteresis. This problem will be accentuated with a long endoscope such as that required in performing colonic procedures. Systems often require multiple operators. To date, the DCE, the R-Scope, the IOP, and the Viacath system have data published relating to their application in human.

CONCLUSION

Alternative forms of instrument actuation, camera control and master console ergonomics should be explored to improve instrument precision, sphere of action, size and minimize assistance required.

2011 update on esophageal achalasia

There have been some breakthroughs in the diagnosis and treatment of esophageal achalasia in the past few years. First, the introduction of high-resolution manometry with pressure topography plotting as a new diagnostic tool has made it possible to classify achalasia into three subtypes. The most favorable outcome is predicted for patients receiving treatment for type II achalasia (achalasia with compression). Patients with typeI(classic achalasia) and type III achalasia (spastic achalasia) experience a less favorable outcome. Second, the first multicenter randomized controlled trial published by the European Achalasia Trial group reported 2-year follow-up results indicating that laparoscopic Heller myotomy was not superior to endoscopic pneumatic dilation (PD). Although the follow-up period was not long enough to reach a convincing conclusion, it merits the continued use of PD as a generally available technique in gastroenterology. Third, the novel endoscopic technique peroral endoscopic myotomy is a promising option for treating achalasia, but it requires increased experience and cautious evaluation. Despite all this good news, the bottom line is a real breakthrough from the basic studies to identify the actual cause of achalasia that may impede treatment success is still anticipated.

A comparative study of endoscopic full-thickness and partial-thickness myotomy using submucosal endoscopy with mucosal safety flap (SEMF) technique

BACKGROUND

Esophageal myotomy using submucosal endoscopy with mucosal safety flap (SEMF) has been proposed as a new treatment of achalasia. In this technique, a partial-thickness myotomy (PTM) preserving the longitudinal outer esophageal muscular layer is advocated, which is different from the usual full-thickness myotomy (FTM) performed surgically. The aim of this study was to compare endoscopic FTM and PTM and analyze the outcomes of each method after a 4 week survival period.

METHODS

Twenty-four pigs were randomly assigned into group A (FTM, 12 animals) and group B (PTM) to undergo endoscopic myotomy. Lower esophageal sphincter (LES) pressure was assessed using pull-through manometry. For statistical analysis we compared the average esophageal sphincter pressure values at baseline, after 2 weeks, and after 4 weeks between groups A and B. The P value was set as <0.05 for significance.

RESULTS

Eighteen animals were included for statistical analysis. Mean (SD) LES pressures were similar between groups A and B (nine animals each) at baseline [group A = 23 (10.4) mmHg; group B = 20.7 (8.7) mmHg; P = 0.79], after 2 weeks [group A = 19 (7.7) mmHg; group B = 21.8 (8.4) mmHg; P = 0.79], and after 4 weeks [group A = 22.6 (10.2) mmHg; group B = 20.7 (9) mmHg; P = 0.82]. LES pressures were significantly reduced in three animals after 4 weeks: one animal (1%) in group A and two animals (2.5%) in group B. An extended myotomy (3 cm below the cardia) was achieved in three animals and was responsible for the significant drop in LES pressure seen in the two animals from group B.

CONCLUSION

Esophageal myotomy using SEMF is a feasible yet challenging procedure in pigs. Full-thickness myotomy does not seem to be superior to partial-thickness myotomy as demonstrated by pull-through manometry. Endoscopic esophageal myotomy results are greatly influenced by obtaining adequate myotomy extension into the gastric cardia.

Transesophageal endoscopic myotomy for achalasia: recognizing potential pitfalls before clinical application

BACKGROUND

Laparoscopic Heller esophagomyotomy is the standard of care for achalasia treatment. This procedure, although effective, must be performed with the patient under general anesthesia and is associated with several serious potential complications. The authors aimed to develop a method of performing transesophageal endoscopic esophagomyotomy (TEEM) that would obviate the need for both general anesthesia and external incisions while offering lower intra- and postoperative complications.

METHODS

The TEEM procedure was performed on eight pigs. For six of the pigs, the procedure aimed at survival. A mid-esophageal mucosal incision was performed using an endoscope, and a submucosal plane was developed. The lower esophageal sphincter (LES) muscle fibers were clearly visualized and divided. The mucosal incision was closed using fibrin sealant. After 2 weeks of survival, a gastrografin swallow study and necropsy were performed.

RESULTS

The TEEM procedure was performed successfully in all eight porcine models. The myotomy included the LES fibers and extended 4 to 6 cm proximally to the esophagus. The proximal gastric muscle was divided up to 1 to 2 cm. No injuries to the abdominal or mediastinal structures occurred. One pig died on postoperative day 1 due to an unrecognized pneumothorax. Two pigs had ischemic ulcers at the myotomy site. The last three pigs had an uneventful recovery. The mucosal incision site healed completely in all the survived pigs, and except for the pig with mediastinal sepsis, all ate heartily and gained weight as expected.

CONCLUSION

The TEEM procedure is technically feasible. Due to the morbidity encountered in the first three pigs, the reported technique was modified to include a slimmer endoscope, a shorter tunnel, and a partial-thickness myotomy. These changes together with an understanding of the pitfalls involved in this procedure led to successful results for the next three pigs. Nevertheless, the authors believe that TEEM is not yet ready for prime time. Perfection of the technique and development of dedicated instruments are mandatory before safe translation of this method to human patients.

A stepwise approach and early clinical experience in peroral endoscopic myotomy for the treatment of achalasia and esophageal motility disorders

BACKGROUND

Peroral endoscopic myotomy (POEM) has recently been described in humans as a treatment for achalasia. This concept has evolved from developments in natural orifice translumenal endoscopic surgery (NOTES) and has the potential to become an important therapeutic option. We describe our approach as well as our initial clinical experience as part of an ongoing study treating achalasia patients with POEM.

STUDY DESIGN

Five patients (mean age 64 ± 11 years) with esophageal motility disorders were enrolled in an IRB-approved study and underwent POEM. This completely endoscopic procedure involved a midesophageal mucosal incision, a submucosal tunnel onto the gastric cardia, and selective division of the circular and sling fibers at the lower esophageal sphincter. The mucosal entry was closed by conventional hemostatic clips. All patients had postoperative esophagograms before discharge and initial clinical follow-up 2 weeks postoperatively.

RESULTS

All (5 of 5) patients successfully underwent POEM treatment, and the myotomy had a median length of 7 cm (range 6 to 12 cm). After the procedure, smooth passage of the endoscope through the gastroesophageal junction was observed in all patients. Operative time ranged from 120 to 240 minutes. No leaks were detected in the swallow studies and mean length of stay was 1.2 ± 0.4 days. No clinical complications were observed, and at the initial follow-up, all patients reported dysphagia relief without reflux symptoms.

CONCLUSIONS

Our initial experience with the POEM procedure demonstrates its operative safety, and early clinical results have shown good results. Although further evaluation and long-term data are mandatory, POEM could become the treatment of choice for symptomatic achalasia.

[Role of laparoscopic surgery in the treatment of achalasia: an analysis of 50 cases]

Achalasia is an uncommon oesophageal motor disorder, with a controversial therapeutic management.

AIM

The aim of our study was to analyse our experience in the management of achalasia, assessing the impact of minimally invasive surgery, its complications and its outcomes in the short and medium term.

METHODS

A retrospective and descriptive study was designed, including all patients operated on between 1999 and 2010 with the diagnosis of achalasia. Previous diagnostic tests, duration of symptoms, previous non-surgical treatment, surgical approach, associated antireflux intervention, surgical time and perioperative complications were analysed.

RESULTS

A total of 50 patients, 24 males and 26 females, with a mean age of 47 years underwent laparoscopic surgery. The mean duration of the disease was 2 years. Eleven (22%) patients had received endoscopic treatment (1-4 sessions) prior to the surgery, with 100% of symptomatic recurrence. The surgery was accompanied by a Dor fundoplication in 48 patients, and Toupet fundoplication in the remaining two. The mean surgical time was 123 minutes. There were 9 intraoperative complications (5 gastric mucosal perforations, 2 bleeding, 1 liver injury and 1 aspiration); 4 postoperative complications (3 scapular pain and 1 sub-phrenic collection) were reported. The long-term subjective symptomatic response was excellent/good in 84% of patients, intermediate in 12% and a poor response in 4%. The mean follow-up was 28 months.

CONCLUSIONS

Heller cardiomyotomy should be the treatment of choice in selected Achalasia patients, because of its short and long term outcomes, and its low morbidity.

Treatment and surveillance strategies in achalasia: an update

Controversy exists with regard to the optimal treatment for achalasia and whether surveillance for early recognition of late complications is indicated. Currently, surgical myotomy and pneumatic dilation are the most effective treatments for patients with idiopathic achalasia, and a multicenter, randomized, international trial has confirmed similar efficacy of these treatments, at least in the short term. Clinical predictors of outcome, patient preferences and local expertise should be considered when making a decision on the most appropriate treatment option. Owing to a lack of long-term benefit, endoscopic botulinum toxin injection and medical therapies are reserved for patients of advanced age and those with clinically significant comorbidites. The value of new endoscopic, radiologic or surgical treatments, such as peroral endoscopic myotomy, esophageal stenting and robotic-assisted myotomy has not been fully established. Finally, long-term follow-up data in patients with achalasia support the notion that surveillance strategies might be beneficial after a disease duration of more than 10-15 years.