Esophagogastric junction distensibility measurements during Heller myotomy and POEM for achalasia predict postoperative symptomatic outcomes

Esophageal impedance planimetry during per-oral endoscopic myotomy guides myotomy extent

INTRODUCTION

Peroral endoscopic myotomy (POEM) is the standard treatment for achalasia. Functional luminal imaging probe (FLIP) technology enables objective measurement of lower esophageal sphincter (LES) geometry, with literature linking specific values to improved post-POEM outcomes. Our study assesses FLIP's intraoperative use in evaluating myotomy extent in real-time.

METHODS

Retrospective data from all patients undergoing POEM with intraoperative FLIP measurements were extracted from June 2020 to January 2023. The primary endpoint was intraoperative FLIP measurements, management changes, and symptom improvement (Eckardt score).

RESULTS

Fourteen patients (age 56 ± 14 years, BMI 28 ± 7 kg/m2) were identified. Most patients were female (64%). Predominantly, patients presented with type II achalasia (50%). FLIP measurements were taken before and after myotomy, demonstrating increases in mean distensibility index (DI) 1.6 ± 1. 4 to 5.4 ± 2.1 mm2/mmHg (p < 0.05) and mean diameter (Dmin) 6 ± 1.8 to 10.9 ± 2.3 mm (p < 0.05) at 50 ml balloon fill. Additional myotomy was performed in one patient when an inadequate increase in FLIP values were noted. Mean operative time was 98 ± 28 min, and there were no intraoperative complications. At the 30-day follow-up, median Eckardt score decreased from mean a preoperative score of 7 ± 2 to a post-operative mean of 2 ± 3, with 10 patients (78%) having a score ≤ 2. In total, four patients experienced symptom recurrence, with repeat FLIP values revealing a significant decrease in DI from 7 ± 2.2 post-POEM to 2.5 ± 1.5 at recurrence. FLIP technology identified LES pathology in 3 out of 4 (75%) patients, facilitating referral to LES-directed therapy.

CONCLUSION

Our study adds to the literature supporting the use of FLIP technology during the POEM procedure, with most patients achieving ideal values after a standard-length myotomy. This suggests the potential benefits of shorter myotomies guided by FLIP to achieve comparable outcomes and reduce postoperative GERD risk. Collaborative standardization of study designs and outcome measures is crucial for facilitating prospective trials and cross-setting outcome comparisons.

Impact of peroral endoscopic myotomy on the endoscopic pressure study integrated system

OBJECTIVES

The endoscopic pressure study integrated system (EPSIS) is an endoscopic diagnostic system utilized for evaluation of lower esophageal sphincter function. Although previous studies have determined that EPSIS was effective as a tool for the diagnosis of achalasia, it remains uncertain if EPSIS can detect significant changes before and after peroral endoscopic myotomy (POEM), which is the premier treatment for achalasia. This study aimed to evaluate the effectiveness of EPSIS as an objective diagnostic tool for assessing the clinical effect of POEM.

METHODS

We conducted a retrospective analysis of patients who underwent POEM from January 2022 to December 2023. The patients underwent EPSIS preoperatively and 2 months postoperatively. Intragastric pressure (IGP) parameters, including the maximum IGP, IGP difference, and waveform gradient were compared pre- and post-POEM. These parameters also were compared between two groups: the postoperative gastroesophageal reflux disease (GERD) group and the non-GERD group.

RESULTS

A total of 50 patients were analyzed. The mean maximum IGP was significantly lower postoperatively than preoperatively (15.0 mmHg vs. 19.8 mmHg, P < 0.001). The mean IGP difference and waveform gradient were also significantly lower postoperatively than preoperatively (8.0 mmHg vs. 12.2 mmHg, P < 0.001; and 0.26 mmHg/s vs. 0.43 mmHg/s, P < 0.001, respectively). The mean postoperative waveform gradient was significantly lower in the GERD group (17 patients, 34%) than in the non-GERD group (33 patients, 66%) (0.207 mmHg vs. 0.291 mmHg, P = 0.034).

CONCLUSION

The results supported the use of EPSIS as an effective diagnostic tool for assessing the effect of POEM.

Recent Advancement and Future Perspective of Per Oral Endoscopic Myotomy

Per oral endoscopic myotomy (POEM) has emerged as a preferred approach for the treatment of idiopathic achalasia and various esophageal motility disorders, offering a minimally invasive alternative to traditional laparoscopic Heller's myotomy. Over the past decade, POEM has solidified its status as the primary therapeutic choice in these conditions through constant improvements. Its evolution has been marked by continuous progress, driven by the integration of innovative technologies and sophisticated techniques. Notable advancements in the techniques include the advent of shorter myotomies and sling fiber-preserving gastric myotomies. The introduction of novel image-enhanced endoscopic techniques, such as red dichromatic imaging and much safer bipolar devices, promises to enhance safety and reduce the technical demands of the POEM procedure. Furthermore, significant strides have been made in understanding gastroesophageal reflux (GERD) following POEM, enabling the differentiation of "true reflux" from acidification resulting from fermentation through manual pH tracing assessment. This distinction aids in identifying cases necessitating treatment with proton pump inhibitors. Other treatment strategies of post-POEM GERD have expanded to the incorporation of NOTES fundoplication and device-assisted fundoplication if the necessity arises. This comprehensive review delves into recent developments in POEM, encompassing technical variations, the assessment and management of post-POEM reflux, outcomes in special populations, and future prospects. By exploring these facets, we aim to provide a comprehensive overview of the current state of POEM, shedding light on its evolution and the promising directions it is poised to take in the field of third-space endoscopy.

Anesthesia choice and its potential impact on endoluminal functional lumen imaging probe measurements in esophageal motility disorders

BACKGROUND AND AIMS

The widespread use of peroral endoscopic myotomy (POEM) has revolutionized the management of esophageal motility disorders (EMDs). The introduction of an endoluminal functional lumen imaging probe (EndoFLIP, Medtronic, Dublin, Ireland) can serve as a complementary diagnostic tool to assess the mechanical properties (ie, pressure, diameter, distensibility, topography) of the esophagus. During EndoFLIP measurements, different anesthesia techniques may induce variable degrees of neuromuscular blockade, potentially affecting esophageal motility and altering the results of EndoFLIP metrics. The aim of this study was to compare the impact of using total intravenous anesthesia (TIVA) versus general anesthesia with inhalational anesthetics (GAIA) on diagnostic EndoFLIP measurements.

METHODS

This retrospective study included all adult patients (≥18 years) undergoing EndoFlip during the POEM procedure at our institution between February 2017 and February 2022. Differences in pressure, diameter, and distensibility index were obtained by using propofol-based TIVA versus sevoflurane-based GAIA with a 30 mL and a 60 mL balloon. The differences were divided into terciles and compared between diagnoses by using univariate comparisons and logistic regression models.

RESULTS

A total of 49 patients were included (39% type I achalasia, 43% type II or III achalasia, and 18% jackhammer esophagus [JE]). Compared with spastic disorders (types II and III achalasia and JE), type I had lower values of pressure differences at 60 mL in univariate (3.75 vs 15.20, P = .001) and multivariate (adjusted odds ratio, .89; 95% confidence interval, .82-.978) analyses. Compared with type I, types II and III achalasia had higher rates of pressure differences at 60 mL in the univariate (9.85 vs 3.75, P = .04) analysis and nearly reached significance in the multivariate analysis (1.09; 95% confidence interval, 1-1.20). Compared with type I achalasia, JE exhibited higher values in pressure differences at 60 mL (27.7 vs 3.75, P < .001).

CONCLUSIONS

Esophageal pressure, as measured by EndoFLIP, was significantly reduced when patients were sedated with sevoflurane-based GAIA. The use of sevoflurane-based GAIA for diagnostic EndoFLIP may potentially lead to the misclassification of spastic disorders as type I achalasia. Propofol-based TIVA should therefore be considered over sevoflurane-based GAIA for sedation during the diagnostic test.

Utility of Intraprocedural Luminal Diameter and Distensibility Measurements During the Esophageal Peroral Endoscopic Myotomy Procedure

GOALS

Through evaluation of the lower esophageal sphincter immediately before and after myotomy using an endoluminal functional lumen imaging probe (EFLIP), our study aimed to determine the clinical response to peroral endoscopic myotomy (POEM) and the incidence of postprocedure reflux.

BACKGROUND

Achalasia is a rare esophageal motility disorder characterized by impaired relaxation of the lower esophageal sphincter (LES) and diminished peristalsis. POEM is a therapeutic option for durable management of achalasia. However, symptomatic acid reflux and esophagitis are well-known adverse effects of the procedure.

STUDY

Electronic medical records of 168 patients who underwent POEM for achalasia at 2 tertiary care referral centers from May 2014 to May 2021 were reviewed. EFLIP was used at a range of catheter fill volumes to assess LES dynamics. Preprocedure and postprocedure Eckardt Symptom Scores were recorded.

RESULTS

Significant clinical improvement from POEM was sustained in over 94% of patients after 1 year. EFLIP changed intraprocedural management 5% of the time by means of myotomy extension. In patients with reflux>1 year following POEM, there was no significant difference in post-POEM LES diameter or change in LES diameter compared with those without reflux. However, post-POEM LES distensibility index (DI) was significantly higher in patients with reflux after 1 year compared with those without reflux.

CONCLUSIONS

POEM is a safe and increasingly effective therapy for patients with symptomatic achalasia. Intraprocedural EFLIP measurements suggest that post-POEM reflux may be correlated more with DI than LES diameter. Yet, more data is needed to substantiate these outcomes.

Impedance planimetry during per-oral endoscopic myotomy is associated with decreased inadvertent capnoperitoneum

BACKGROUND

Per-oral endoscopic myotomy (POEM) has become an accepted minimally invasive alternative to Heller myotomy for the treatment of achalasia and other disorders of esophageal dysmotility. One associated adverse event is the inadvertent creation of capnoperitoneum. A proposed mechanism is that extension of the submucosal tunnel below the esophageal hiatus and onto the gastric wall leads to transmural perforation. We hypothesized that the use of impedance planimetry with the endoscopic functional luminal imaging probe (EndoFLIP) more accurately identifies the esophagogastric junction and helps to better define the myotomy's ideal limits, thus lowering the incidence of inadvertent capnoperitoneum.

METHODS

This is a single-center, retrospective review of consecutive POEM cases from 06/11/2011 to 08/08/2022, with EndoFLIP introduced in 2017. Patient and procedural characteristics, including the incidence of clinically significant capnoperitoneum and decompression, were analyzed using univariate and multivariable linear regression statistics.

RESULTS

There were 140 POEM cases identified, 74 (52.9%) of which used EndoFLIP. Clinically significant capnoperitoneum was encountered in 26 (18.6%) cases, with no differences in patient characteristics between those who had capnoperitoneum and those who did not. There was a decreased incidence of capnoperitoneum in cases using EndoFLIP compared to those without (n = 6, 23% vs n = 20, 77%, p = 0.001), with zero instances in the final 56 cases. After adjusting for potentially confounding factors, EndoFLIP use was associated with a - 15.93% (95% confidence interval - 30.68%, - 1.18%) decrease in procedure duration.

CONCLUSIONS

The routine use of EndoFLIP during POEM was associated with decreased incidence of clinically significant capnoperitoneum, potentially due to improved myotomy tailoring and decreased duration of insufflation with shorter procedure times.

Interventional functional diagnostics in gastrointestinal endoscopy: Combining diagnostic and therapeutic tools in the endoscopy suite with the functional lumen imaging probe

With technical progress of gastrointestinal functional testing, there has been a demand for more comprehensive examination of esophageal physiology and pathophysiology beyond high-resolution manometry. A new interventional technology based on impedance planimetry, the functional lumen imaging probe (FLIP), enables intraluminal measurement of distensibility and compliance of hollow organs. EndoFLIP uses balloon catheters to measure diameter and distension pressure to calculate cross-sectional area and distensibility in different organs (mostly esophagus, stomach, anorectal region) and can be used in wide variety of indications (diagnostics, pre- and post-treatment evaluation) and currently serves as a helpful adjunctive tool in ambiguous clinical cases. EsoFLIP is a therapeutic variation that uses a stiffer balloon catheter allowing for dilation. The trend to simplify the clinical process from diagnosis to treatment tends to a one-session procedure combining diagnostics and therapeutic interventions. In specified conditions like e.g. achalasia or gastroparesis, a combination of EndoFLIP and EsoFLIP procedures may therefore be useful. The aim of this narrative review is to introduce the clinical use of FLIP and its potential benefit in combined diagnostic-therapeutic procedures.

Mini-review: Tailored per-oral endoscopic myotomy for type III achalasia

This mini-review summarizes the most recent literature regarding per-oral endoscopic myotomy for type III achalasia, emphasizing the poorly understood science of tailoring myotomy length during this procedure. In addition, special attention will be placed on the current subjective and objective biomarkers, such as the Eckardt score, used to evaluate treatment outcomes in this population to better contextualize the existing data on patient outcomes, as proposed by Low et al in the current issue of the Journal. Understanding the current treatment landscape for type III achalasia and identifying the key areas of research deficiencies will guide future investigation and management of this disease.

Intraoperative distensibility measurement in POEM for achalasia: impact on patient outcome and associations with other outcome variables at 1-year follow-up

BACKGROUND AND AIMS

The functional luminal imaging probe (FLIP) can provide measurements of lower esophageal sphincter (LES) distensibility. Studies report that use of intraoperative FLIP examination during peroral endoscopic myotomy (POEM) for achalasia is associated with treatment success, but evidence is limited and inconsistent. The main aim of the present study was to assess associations between intraoperative FLIP values and 1-year outcomes. Additionally, associations between 1-year FLIP measurements and other 1-year outcome variables were studied.

METHODS

We performed a single-center prospective study of consecutive achalasia patients treated with POEM with a standardized 1-year follow-up. The inclusion period was from June 2017 to January 2020. We compared 1-year outcomes (FLIP measurement values, Eckardt score (ES), reflux esophagitis, timed barium esophagogram (TBE), and lower esophageal sphincter resting pressure (LES-rp)) in patients with and without intraoperative FLIP examination. We also assessed associations between intraoperative FLIP values, 1-year FLIP values, and other 1-year outcomes. Results are given as median (IQR), and non-parametrical statistical analyses were applied.

RESULTS

Sixty-two patients (27 females) with median age 45 years (35-54) were included. Baseline characteristics were similar in patients with (n = 32) and without (n = 30) intraoperative FLIP examination. In patients with intraoperative FLIP, ES was 2 (1-3) and LES distensibility index (DI) 3.7 (2.6-5.4) after 1 year, compared with ES 2 (1-3) and DI 4.0 (3.1-6.8)) in patients without intraoperative FLIP (ns). Intraoperative DI was not correlated with 1-year ES or DI. One-year DI correlated significantly with 1-year ES (rs - 0.42), TBE (rs - 0.34), and LES-rp (rs - 0.29).

CONCLUSIONS

Use of intraoperative FLIP measurements in POEM for achalasia is not associated with improved 1-year outcome, and the clinical value of intraoperative FLIP in POEM for achalasia is questioned. Follow-up FLIP measurements are moderately associated with symptomatic outcome, and may serve as an additional diagnostic modality in post-treatment evaluation.

Precision Endoscopy in Peroral Myotomies for Motility Disorders of the Upper Gastrointestinal Tract: Current Insights and Prospective Avenues-A Comprehensive Review

Our review delves into the realm of peroral endoscopic myotomies (POEMs) in the upper gastrointestinal tract (UGT). In recent years, POEMs have brought about a revolution in the treatment of UGT motility disorders. Esophageal POEM, the first to be introduced, has now been validated as the primary treatment for achalasia. Subsequently developed, G-POEM displays promising results in addressing refractory gastroparesis. Over time, multiple endoscopic myotomy techniques have emerged for the treatment of Zenker's diverticulum, including Z-POEM, POES, and hybrid approaches. Despite the well-established efficacy outcomes, new challenges arise in the realm of POEMs in the UGT. For esophageal POEM, the future scenario lies in customizing the myotomy extent to the minimum necessary, while for G-POEM, it involves identifying patients who can optimally benefit from the treatment. For ZD, it is crucial to validate an algorithm that considers various myotomy options according to the diverticulum's size and in relation to individual patients. These challenges align with the concept of precision endoscopy, personalizing the technique for each subject. Within our text, we comprehensively examine each myotomy technique, analyzing indications, outcomes, and adverse events. Additionally, we explore the emerging challenges posed by myotomies within the context of the evolving field of precision endoscopy.

Role of short interval FLIP panometry in predicting long-term outcomes after per-oral endoscopic myotomy

BACKGROUND

The Eckardt score (ES) is used to assess symptom response to Per-Oral Endoscopic Myotomy (POEM), but reliable methods to assess physiologic success are needed. Functional lumen imaging probe (FLIP) panometry has a potential role in post-POEM follow-up to predict long-term outcomes. The aim of this study was to assess the correlation between clinical success and FLIP parameters following POEM to determine if short interval FLIP could predict long-term outcomes.

METHODS

This was a prospective study of adult patients who underwent POEM with short interval follow-up FLIP between 11/2017 and 3/2020. Clinical success was defined as post-procedure ES ≤ 3. Physiologic success was based on an esophago-gastric junction distensibility index (EGJ-DI) > 2.8 mm2/mmHg on FLIP.

RESULTS

47 patients (55% female, mean age 55 years) were included in the study. Clinical success after POEM was seen in 45 (96%) patients (mean ES 6.5 ± 2.2 pre and 0.83 ± 1.0 post-POEM, p < 0.001). Physiologic success was noted in 43 (91.5%) patients (mean EGJ-DI 6.1 mm2/mmHg ± 2.5). Among 4 patients not meeting criteria for physiologic success, EGJ-DI was 2.5-2.6. There was no correlation between post-POEM EGJ-DI and ES in the short term or long term. Significant reflux esophagitis was seen in 6 (12.8%) patients with no difference in mean EGJ-DI with vs without esophagitis (5.9 vs 6.1, p = 0.44).

CONCLUSION

Post-POEM endoscopy with FLIP is useful to both assess EGJ physiology and to examine for reflux esophagitis. Short interval FLIP has limited utility to predict long-term patient outcomes or risk of acid reflux.

What role does the submucosa play in the pathophysiology and treatment of achalasia? An analysis of impedance planimetry during POEM

BACKGROUND

It is thought the therapeutic benefit of per-oral endoscopic myotomy (POEM) in the treatment of esophageal dysmotility disorders is from longitudinal myotomy creation, but it is unknown if the submucosa contributes to the pathophysiology. This study investigates if submucosal tunnel (SMT) dissection alone contributes to POEM's luminal changes as measured by EndoFLIP.

METHODS

A single-center, retrospective review of consecutive POEM cases from June 1, 2011 to September 1, 2022 with intraoperative luminal diameter and distensibility index (DI) data as measured by EndoFLIP. Patients with diagnoses of achalasia or esophagogastric junction outflow obstruction were grouped by those with pre-SMT and post-myotomy measurements (Group 1) and those with a third measurement post-SMT dissection (Group 2). Outcomes and EndoFLIP data were analyzed using descriptive and univariate statistics.

RESULTS

There were 66 patients identified, of whom 57 (86.4%) had achalasia, 32 (48.5%) were female, and median pre-POEM Eckardt score was 7 [IQR: 6-9]. There were 42 (64%) patients in Group 1, and 24 (36%) patients in Group 2, with no differences in baseline characteristics. In Group 2, SMT dissection changed luminal diameter by 2.15 [IQR: 1.75-3.28]cm, which comprised 38% of the median 5.6 [IQR: 4.25-6.3]cm diameter of complete POEM change. Similarly, the median post-SMT change in DI of 1 [IQR: 0.5-1.2]units comprised 30% of the median 3.35 [2.4-3.98]units overall change in DI. Post-SMT diameters and DI were both significantly lower than the full POEM.

CONCLUSIONS

Esophageal diameter and DI are significantly affected by SMT dissection alone, though not equaling the magnitude of diameter or DI changes from full POEM. This suggests that the submucosa does play a role in achalasia, presenting a future target for refining POEM and developing alternative treatment strategies.

Use of endolumenal functional lumen imaging probe in investigating paediatric gastrointestinal motility disorders

Investigating gastrointestinal (GI) motility disorders relies on diagnostic tools to assess muscular contractions, peristalsis propagation and the integrity and coordination of various sphincters. Manometries are the gold standard to study the GI motor function but it is increasingly acknowledged that manometries do not provide a complete picture in relation to sphincters competencies and muscle fibrosis. Endolumenal functional lumen imaging probe (EndoFLIP) an emerging technology, uses impedance planimetry to measure hollow organs cross sectional area, distensibility and compliance. It has been successfully used as a complementary tool in the assessment of the upper and lower oesophageal sphincters, oesophageal body, the pylorus and the anal canal. In this article, we aim to review the uses of EndoFLIP as a tool to investigate GI motility disorders with a special focus on paediatric practice. The majority of EndoFLIP studies were conducted in adult patients but the uptake of the technology in paediatrics is increasing. EndoFLIP can provide a useful complementary data to the existing GI motility investigation in both children and adults.

Early outcomes following EndoFLIP-tailored peroral endoscopic myotomy (POEM): the establishment of POEM services in two UK centers

Peroral endoscopic myotomy (POEM) is a safe and effective minimally invasive treatment for achalasia. Postoperative reflux rates remain high. The functional luminal imaging probe (FLIP) allows intraoperative measurement of lower esophageal distensibility during POEM. In theory, this enables a tailoring of myotomies to ensure adequate distensibility while minimizing postoperative reflux risk. Two prospectively collected POEM databases were analyzed from two UK tertiary upper GI centers. The operators in each center used FLIP measurements to ensure adequate myotomy. Outcome measures included Eckardt score (where <3 indicated clinical success) and proton-pump inhibitor use (PPI), collected at the first postoperative appointment. Length of stay was recorded as were complications. In all, 142 patients underwent POEM between 2015 and 2019. Overall, 90% (128/142) had postoperative Eckardt scores of <3 at 6 weeks. Clinical success improved to 93% (66/71) in the latter half of each series with a significantly higher rate of complete symptom resolution (53 versus 26%, P = 0.003). In all, 79% of the poor responders had previous interventions compared with 55% of responders (P = 0.09). Median post-myotomy distensibility index was 4.0 mm2/mmHg in responders and 2.9 in nonresponders (P = 0.16). Myotomy length of <7 cm was associated with 93% clinical success and 40% post op PPI use compared with 60% PPI use with longer myotomies. There were two type IIIa, two type IIIb, and one IV Clavien-Dindo complications. This is the largest series of endoluminal functional lumen imaging probe (EndoFLIP)-tailored POEM in the UK to date. The shorter myotomies, allowed through EndoFLIP tailoring, remained clinically effective at 6 weeks. Complete symptom response rates improved in the latter half of each series. More data will be needed from high-volume collaborations to decipher optimal myotomy profiles based on EndoFLIP parameters.

Experience with Impedance Planimetry for Surgical Foregut Disease in 1,097 Cases

BACKGROUND

The geometry and compliance of gastrointestinal sphincters may be assessed by impedance planimetry using a functional lumen imaging probe (FLIP). We describe our institutional foregut surgeon experience using FLIP in 1,097 cases, highlighting instances where FLIP changed operative decision making.

STUDY DESIGN

A retrospective review of an IRB-approved prospective quality database was performed. This included operative and endoscopic suite foregut procedures using FLIP between February 2013 and May 2022.

RESULTS

During the study period, FLIP was used a total of 1,097 times in 919 unique patients by 2 foregut surgeons. Intraoperative FLIP was used during 573 antireflux procedures and 272 endoscopic myotomies. FLIP was also used during 252 endoscopic suite procedures. For those undergoing preoperative workup of GERD, starting in 2021, esophageal panometry was performed in addition to standard FLIP measurements at the lower esophageal sphincter. In 77 cases, intraoperative FLIP changed operative decision making. During antireflux procedures, changes included adding or removing crural sutures, adjusting a fundoplication tightness, choice of full vs partial wrap, and magnetic sphincter augmentation sizing. For endoscopic procedures, changes included aborting peroral endoscopic myotomy or Zenker's peroral endoscopic myotomy, performing a myotomy when preoperative diagnosis was unclear, or performing additional myotomy.

CONCLUSIONS

FLIP is a useful tool for assessing the upper esophageal sphincter, lower esophageal sphincter, pylorus, and secondary esophageal peristalsis that can be used in a wide variety of clinical situations within a foregut surgeon's practice. It can also function as an adjunct in intraoperative decision making.

Peroral esophageal myotomy for esophageal motility disorders

The concept of third space endoscopy first described in 2007, was adapted and performed in humans in 2010 by Inoue et al. in a group of patients with esophageal achalasia (EA). Since then, esophageal endoscopic myotomy (E-POEM), has been performed in more than 10,000 patients worldwide up to now. Safety and efficacy have been confirmed at early, mid and long-term evaluations, in different gastrointestinal diseases including achalasia, refractory gastroparesis, and other esophageal motility disorders (EMD). Nowadays, this treatment has shown to be not only an excellent option, but also with its excellent outcomes, the first option in certain clinical scenarios such as type III achalasia. Thus, the minimal invasive nature of POEM gives us multiple advantages compared with the classical treatments that includes pneumatic dilation (PD) and laparoscopic Heller myotomy (LHM), including not only clinical aspects but also economical. High resolution manometry (HRM) has substantially redefined the actual approach of esophageal motility disorders with the major changes in instrumental use, diagnostic algorithms, and therapeutics. The previous Chicago's classification V 3.0 clearly improved our knowledge about pathophysiology of spastic esophageal motor disorders, however, with its recent update (Chicago V 4.0), multiple changes in diagnosis and treatment are expected. In the present article, we aimed to review and analyze the most important aspects about the results of E-POEM in the management of EMD according to the view of the new Chicago's classification V 4.0.

Probability of additional intervention and long-term follow-up of esophagomyotomy

INTRODUCTION

Two common surgical procedures used to treat esophageal motility disorders are laparoscopic Heller myotomy (LHM) with partial fundoplication and per-oral endoscopic myotomy (POEM). The difference in frequency of follow-up interventions following these procedures is unknown. This study was designed to report differences in post-surgical interventions as one of the major long-term follow-up expectations.

METHODS

An IRB approved registry was used to identify all patients undergoing surgery with LHM or POEM. Following surgery, patients requiring additional interventions with esophageal non-pneumatic dilation, botox injection, or repeat myotomy, as well as persistent proton pump inhibitor (PPI) use were recorded. Multivariable logistic regression analysis was performed to estimate risk factors associated with return for additional post-operative intervention.

RESULTS

A total of 203 patients were identified, 139 met inclusion criteria (33 LHM and 106 POEM). There was a higher rate of non-pneumatic EGD dilation (33% vs 15%, p = 0.04), repeat myotomy (18% vs 2%, p < 0.01), and higher rate of overall post-operative intervention in LHM than POEM. With POEM, there was a higher rate of post-operative PPI use (63 vs 29%, p < 0.01). There was no difference in time to post-operative intervention for either group, but if intervention were to occur the median time was within the first year. Patients with a change in pre- to post-operative Eckardt score of 4 or greater decreased their chance of having a post-operative intervention.

CONCLUSION

Our results for both LHM and POEM emphasize the importance of long-term follow-up in patients with an esophageal motility disorder. We have found that patients undergoing LHM are more likely to have a post-operative intervention as well as a higher rate of repeat myotomy than POEM. With both interventions, a greater change in Eckardt score decreased the likelihood of reintervention.

Esophagogastric junction compliance on impedance planimetry (EndoFLIP™) following peroral endoscopic myotomy (POEM) predicts improvement in postoperative eckardt score

BACKGROUND

Peroral endoscopic myotomy (POEM) is a mainstay of treatment for achalasia. Tailored myotomy based on compliance, as measured with impedance planimetry (FLIP), has yet to be described. In this study we describe the associations between Eckardt score, postoperative GERD, and compliance.

METHODS

A retrospective review of a prospectively maintained database was performed, evaluating patients who underwent POEM and intraoperative FLIP between January 2019 and November 2021. Group comparisons were made using two-tailed Wilcoxon rank-sum and Fisher's exact tests. Spearman's correlation coefficients (r) were used to assess the relationship between compliance and outcomes, all with two-tailed statistical significance of p < 0.05.

RESULTS

Thirty five patients underwent POEM with intraoperative FLIP. At a 30 mL and 40 mL fill, respectively, compliance increased by 80% (180 ± 152%) and 77% (177 ± 131%) from pre to post myotomy. Mean Eckardt score improved from 5.5 ± 2.6 preoperatively to 1.3 ± 1.6 and 1.8 ± 1.9 at first and second follow up, respectively. Median times to first and second follow up were 22 days (IQR 16-23) and 65 days (IQR 58-142). A higher compliance at 40 mL fill was moderately associated with lower Eckardt score at first (r = -0.49, p = 0.012) and second (r = -0.64, p = 0.014) follow up. Post myotomy compliance ≥ 125 mm³/mmHg at 40 mL fill was associated with lower Eckardt scores, < 3, at first (0.4 ± 0.5 vs 1.8 ± 1.3, p = 0.008) and second (0.4 ± 0.5, vs 2.0 ± 1.4, p = 0.027) follow up. Compliance ≥ 125 mm³/mmHg performed better than previously defined ideal ranges of DI and CSA in predicting postoperative Eckardt scores. Compliance was not significantly associated with development of postoperative GERD.

CONCLUSIONS

A target post myotomy compliance of ≥ 125 mm³/mmHg at a 40 mL fill is associated with normal Eckardt scores at first and second postoperative visits, and performs better than previously defined ideal ranges of DI and CSA in predicting post-operative Eckardt scores. Compliance is a poor predictor of developing GERD after POEM.

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..

Changes in impedance planimetry (EndoFLIP) measurements at follow-up after peroral endoscopic myotomy (POEM)

BACKGROUND

Numerous studies show changes in functional lumen imaging probe (FLIP) measurements after myotomy during peroral endoscopic myotomy (POEM), but few report on FLIP measurements at follow-up esophagogastroduodenoscopy (EGD). The purpose of this study was to compare perioperative FLIP measurements to those at follow-up EGD.

METHODS

Patients who underwent POEM with FLIP in the operating room and POEM patients who had EGD with FLIP at follow-up were included. FLIP measurements, including diameter (Dmin), pressure, cross-sectional area (CSA), and distensibility index (DI), were analyzed at a 30-mL balloon fill. Differences between measurements at different timepoints were assessed using a two-tailed Wilcoxon signed-rank test.

RESULTS

A total of 97 patients who underwent POEM and 28 who underwent EGD with FLIP were analyzed. The average age was 63 ± 18 years and 46.4% of the patients were male. Mean preoperative Eckardt score was 6.5 ± 4.8, decreasing to 1.6 ± 2.0 at follow-up. EGDs were performed at a median of 15 months after surgery. When compared to mean measurements obtained post-myotomy, at the time of EGD, pressure was found to be significantly lower (p = 0.007) and DI significantly higher (p = 0.045). Of the patients who underwent EGD, 70.8% had an increase in DI, 55.6% had evidence of reflux esophagitis, and 81.0% met diagnostic criteria for reflux on esophageal pH monitoring. However, there was no correlation with the development of esophagitis or reflux and increase or decrease in DI at follow-up.

CONCLUSIONS

There are significant changes in FLIP measurements between the time of surgery and at follow-up EGD. These results suggest that esophageal remodeling may cause changes in lower esophageal sphincter geometry after POEM and postoperative FLIP targets immediately post-myotomy may need to be adjusted to account for these changes.

Impedance planimetry (EndoFLIP) assisted laparoscopic esophagomyotomy in pediatric population

INTRODUCTION

Functional lumen imaging probe (EndoFLIP) is a diagnostic technology that assesses esophageal cross-sectional area via impedance planimetry during controlled volumetric distention. The purpose of this study is to evaluate the utility of EndoFLIP intraoperatively during laparoscopic esophagomyotomy.

METHODS

We performed a retrospective cohort study reviewing all patients undergoing EndoFLIP assisted laparoscopic esophagomyotomy for achalasia between January and December 2021 (n = 10). Twenty-two patients with achalasia that underwent traditional laparoscopic esophagomyotomy between July 2014 and September 2019 served as a comparison. Primary outcome evaluated was resolution of symptoms at discharge. Secondary outcomes included change in distensibility index (DI), operative time, length of stay, time to regular diet, and reinterventions.

RESULTS

All patients managed with EndoFLIP assistance had resolution of dysphagia and postprandial vomiting following intervention. Mean change in DI was 5.32 mm²/mmHg with a myotomy length of 3.6 cm. Operative time was shorter in the EndoFLIP cohort (97 min versus 185 min, p = <0.001). Study patients did not undergo an antireflux operation. There was no difference in length of stay or time to soft diet between groups. All patients were discharged on postoperative day 1 tolerating a mechanical soft diet. No acid suppressive medications were prescribed during the observation period. One patient required dilation for recurrent symptoms and one required reoperation for mucosal leak.

CONCLUSION

EndoFLIP assisted laparoscopic esophagomyotomy results in similar short-term outcomes to traditional surgical technique. EndoFLIP allows for focused myotomy length and a shorter operative time.

LEVEL OF EVIDENCE

III.

Efficacy and safety of endoscopic pyloric balloon dilation in patients with refractory gastroparesis

BACKGROUND AND AIMS

There has been interest in the use of pyloric therapies for the treatment of refractory gastroparesis. However, data on endoscopic pyloric dilation are scarce. We aimed to assess the efficacy and safety of this procedure in refractory gastroparesis.

METHODS

We performed a retrospective analysis of 47 patients referred for refractory gastroparesis, confirmed by gastric emptying scintigraphy, and treated with endoscopic pyloric through-the-scope balloon dilation. The primary endpoint was the effectiveness of the procedure, evaluated with the Gastric Cardinal Symptom Index (GCSI) at 2 and 6 months.

RESULTS

A clinical response, defined by a 1.0 point decrease in the GCSI score, was observed in 25 patients at 2 months (53%) and in 19 patients at 6 months (40%). The mean GCSI score decreased significantly at 2 and 6 months compared to the preoperative score (3.9 ± 0.87 vs 2.3 ± 1.37 and 3.9 ± 0.87 vs 2.9 ± 1.27, respectively; p < 0.0001). No complication was observed. Nine patients had a delayed relapse at 1 year. A second dilation was performed for eight patients and it was effective in five of them (63%). The mean follow-up time of the patients was 27.0 ± 10.4 months. At 2 years, 15 patients still experienced improvement following this treatment (32%). No predictive factor of clinical response was identified.

CONCLUSION

The efficacy of pyloric dilation is 53% at 2 months, with sustained improvement in one third of patients at 2 years. This treatment should be considered as an alternative option to pyloromyotomy.

Gastroesophageal Reflux Waning Over Time in Endoscopic Versus Surgical Myotomy for the Treatment of Achalasia: A Systematic Review and Meta-Analysis

Peroral endoscopic myotomy (POEM) and Heller myotomy with fundoplication (HMF) effectively treat achalasia, an esophageal motor disease. Although a significant number of meta-analyses have compared POEM and HMF, these studies showed discrepant postoperative gastroesophageal reflux disease (GERD) conclusions. This review aimed to objectively compare GERD over time, as well as the efficiency, safety, and adverse events in POEM versus HMF for treating achalasia. We performed a systematic review and meta-analysis by searching Medline, Embase, Cochrane Library, Scopus, and Clinicaltrials.gov. The evaluated outcomes included early (within 12 months) and late (beyond 12 months) endoscopic assessment of GERD using the Lyon Consensus, clinical success, operative duration (OD), length of stay (LOS), and major adverse events (MAE). A total of 29 observational studies and two randomized clinical trials (RCTs) with 13,914 patients were included. GERD was 28% higher among RCTs discussing POEM at early assessment (95%CI 0.02, 0.54) and was not different at late evaluation (95% confidence interval (CI) = 0.00, 0.22). No difference in reflux was observed among observational studies in both periods. The clinical success was 9% higher (95% CI = 0.05, 0.12), and the OD was 37.74 minutes shorter (95% CI = -55.44, -20.04) in POEM among observational studies, whereas it was not different among RCTs. The LOS and MAE were similar in the groups. Comparisons among studies yielded divergent results. RCTs revealed that POEM had a higher incidence of GERD in the early assessment, whereas observational studies showed higher clinical success and a shorter OD in POEM. Ultimately, the between-group difference waned over time in GERD in all comparisons, resulting in no difference among RCTs in the late evaluation. Our meta-analysis demonstrated a non-preferential treatment of achalasia between endoscopic or surgical cardiomyotomy, prioritizing an individualized approach in the long term.

Role of functional luminal imaging probe in the management of postmyotomy clinical failure

BACKGROUND AND AIMS

A small percentage of patients with esophageal dysmotility disorders (EDDs) fail to improve or relapse after management by laparoscopic Heller myotomy (LHM) and peroral endoscopic myotomy (POEM). In this study, we aimed to describe the role of functional luminal imaging probe (FLIP) in identifying patients who might benefit from lower esophageal sphincter (LES)-directed retreatment.

METHODS

This was a retrospective study at 6 tertiary care centers (United States, 4; Europe, 1; Asia, 1) between January 2015 and April 2021 involving patients with prior failed myotomy. The primary outcome was the impact of the use of FLIP on the management of patients with prior failed myotomy.

RESULTS

One hundred twenty-three patients (62 women [50%]; mean age, 53 ± 21.1 years) who underwent LHM (n = 53, 43%) or POEM (n = 70, 57%) for the management of achalasia (n = 98) or other EDDs (n = 25) had clinical failure at a median time of 10.8 months (interquartile range, .8-17.3) postprocedure. Twenty-nine patients had apposing "abnormal" diagnoses in terms of integrated relaxation pressure (IRP) >15 mm Hg on HRM and distensibility index (DI) <2.8 mm²/mm Hg on FLIP, with ultimate change in management noted in 15 patients (10 directed toward conservative management, 5 directed toward LES-directed retreatment). The impact of FLIP on both diagnosis and management was noted in 15 of 29 patients (52%). In the subgroup analysis of 44 patients who underwent LES-directed retreatment, clinical success was highest among patients with both abnormal IRP and DI (21/25 [84%]) versus patients with only abnormal IRP (8/14 [57%]) or only abnormal DI (3/5 [60%], P = .04), with DI at 40-mL distension volume on FLIP identified as an independent predictor of clinical success (odd ratio, 1.51; 95% confidence interval, 1.02-2.1; P = .03).

CONCLUSIONS

The finding of this study further suggests the important role of using FLIP in addition to HRM in evaluating patients with clinical failure postmyotomy.

Changes in Distensibility Index During an Incremental POEM Myotomy

BACKGROUND

A longer myotomy for the treatment of achalasia is associated with worse gastroesophageal reflux disease despite palliating dysphagia. Recently, clinical outcomes have been correlated to the distensibility of the distal esophagus, which is measured intra-operatively using an endoscopic functional luminal image probe (EndoFLIP). We aimed to determine the minimum per oral endoscopic myotomy (POEM) length to allow for adequate distensibility index (DI).

METHODS

A 6-cm myotomy conducted in 2-cm increments during POEM was performed for patients with achalasia I and II from 2017 to 2019. The EndoFLIP was used to measure the DI intra-operatively: (1) prior to intervention, (2) following creation of the submucosal tunnel, (3) following transection of the high-pressure zone (HPZ), (4) following the distal extension, and (5) following the proximal esophageal extension.

RESULTS

A total of 16 patients underwent POEM. Ages ranged from 21 to 78 years, 10 were male, and 13 had type II achalasia. The median DI was 2.7 (1.4-3.6) mm²/mmHg prior to intervention; 2.4 (1.4-3.3) mm²/mmHg following the submucosal tunnel; 3.2 (1.6-4.4) mm²/mmHg following transection of the HPZ; 3.8 (2.6-4.5) mm²/mmHg following the gastric extension; and 4.5 (3.3-7.1) mm²/mmHg following the proximal extension. Our target range DI was achieved for 50% of patients after transection of the HPZ.

CONCLUSIONS

Distensibility changed with each myotomy increment and fell within the target range for most patients following a 2-4-cm myotomy. This suggests that a shorter myotomy may be appropriate for select patients, and the use of the EndoFLIP intra-operatively may allow for a tailored myotomy length.

Comparison of functional lumen imaging probe and high-resolution manometry to assess response after peroral endoscopic myotomy

BACKGROUND AND AIMS

Outcomes after peroral endoscopic myotomy (POEM) are assessed clinically by the Eckardt score (ES) or objectively by high-resolution manometry (HRM) and functional lumen imaging probe (FLIP). This study compared HRM and FLIP to evaluate clinical response after POEM.

METHODS

This was a single tertiary center retrospective study of consecutive patients who underwent POEM for treatment-naive achalasia and with ≥6 months of follow-up. Baseline and follow-up testing in all patients included ES, HRM, and FLIP of the esophagogastric junction (EGJ). A normal post-POEM (or normalized) EGJ distensibility index (EGJ-DI) >2.8 mm²/mm Hg, maximum EGJ diameter (MxEGJD) ≥14 mm, and integrated relaxation pressure (IRP) <15 mm Hg were compared with a clinical response, defined as ES ≤3.

RESULTS

Eighty-seven patients (58% men, mean age 51 ± 17 years) were included. Overall clinical response by ES, IRP, MxEGJD, and EGJ-DI were 97.7%, 86.2%, 75.9%, and 92.0%, respectively. The sensitivity of a normal IRP (87.1% [95% confidence interval {CI}, 78.0-93.4]) was similar to the sensitivity of a normal MxEGJD (75.3% [95% CI, 64.7-84.0], P = .053) and normal EGJ-DI (91.8% [95% CI, 83.8%-96.6%], P = .39) after POEM to predict clinical response. However, the sensitivity of a normal post-POEM EGJ-DI was superior to a normal post-POEM MxEGJD (P = .001) to predict clinical response. There was no difference in the area under the curve of a normal MxEGJD or EGJ-DI to predict a normal IRP (P = .956) after POEM.

CONCLUSIONS

Normal FLIP metrics ≥6 months after POEM for achalasia show good to excellent sensitivity but are equivalent to a normalized IRP by HRM to predict clinical response by ESs. FLIP may be used as an alternative to HRM to assess lower esophageal sphincter response to POEM in these patients. (Clinical trial registration number: NCT02770859.).

Functional Luminal Imaging Probe in the Management of Pediatric Esophageal Disorders

BACKGROUND

Functional luminal imaging probe (FLIP) measures pressure-geometry relationships of digestive luminal space. When used in esophageal disorders, it provides several luminal parameters that help better understand the pathophysiology. Data about the potential utility of FLIP in pediatrics are scarce and there is no standardized use in children. We aim to describe the use of FLIP in our center, its safety, feasibility, and clinical impact in esophageal disorders in children.

METHODS

Consecutive FLIP recordings performed at the Centre Hospitalier Universitaire-Sainte-Justine, Montréal, Canada between February 2018 and January 2021 were extracted. A chart review was conducted for demographics and medical history. Symptomatology after the procedure was evaluated with validated dysphagia scores.

KEY RESULTS

Nineteen patients were included (11 girls, median age 16 years, range 3.2-19.6) with achalasia (n = 5), post-Heller's myotomy dysphagia (n = 3), esophagogastric junction outflow obstruction (n = 3), congenital esophageal stenosis (n = 2); post-esophageal atresia repair stricture (n = 3), and post-fundoplication dysphagia (n = 3). There was no significant correlation between integrated relaxation pressure measured with high resolution manometry and distensibility index (DI). The use of FLIP made it possible to differentiate between dysphagia related to an esophageal obstruction (DI < 2.8 mm2/mmHg) and dysphagia without major motility disorder (DI > 2.8 mm2/mmHg) that guided the indication for dilation. FLIP led to a change in management in 47% of the patients. Forty-seven percent of the patients were symptom free at the time of the evaluation.

CONCLUSIONS INFERENCES

FLIP provides key esophageal luminal values and therefore can play an important role in pediatric esophageal disorders management.

Peroral endoscopic longer vs shorter esophageal myotomy for achalasia treatment: A systematic review and meta-analysis

BACKGROUND

Peroral endoscopic myotomy (POEM) has been demonstrated to be safe and effective in the treatment of achalasia. Longer myotomy is the standard POEM procedure for achalasia but when compared with shorter myotomy, its effectiveness is not as well known.

AIM

To compare the clinical effectiveness of longer and shorter myotomy.

METHODS

PubMed, EmBase, Cochrane Library, web of science and clinicaltrials.gov were queried for studies comparing shorter and longer POEM for achalasia treatment. The primary outcome was clinical success rate. Secondary outcomes comprised of operative time, adverse events (AEs) rate, gastroesophageal reflux disease (GERD) and procedure-related parameters. The Mantel-Haenszel fixed-effects model was primarily used for the analysis. Publication bias was assessed.

RESULTS

Six studies were included in this analysis with a total of 514 participants. During the follow-up period of 1-28.7 mo, longer and shorter myotomy in treating achalasia showed similar excellent effectiveness [overall clinical success (OR = 1, 95%CI: 0.46-2.17, P = 1, I²: 0%; subgroup of abstract (OR = 1.19, 95%CI: 0.38 to 3.73; P = 0.76; I²: 0%); subgroup of full text (OR = 0.86 95%CI: 0.30 to 2.49; P = 0.78; I²: 0%)]. Shorter myotomy had significantly reduced mean operative time compared with the longer procedure. There were no statistically significant differences in AEs rates, including GERD (overall OR = 1.21, 95%CI: 0.76-1.91; P = 0.42; I²: 9%; subgroup of abstract OR = 0.77, 95%CI: 0.40-1.47; P = 0.43; I²: 0%; subgroup of full text OR = 1.91, 95%CI: 0.98-3.75; P = 0.06; I²: 0%), hospital stay (overall MD = -0.07, 95%CI: -0.30 to 0.16; P = 0.55; I²: 24%; subgroup of abstract MD = 0.20, 95%CI: -0.25 to 0.65; P = 0.39; I²: 0; subgroup of full text MD = -0.16, 95%CI: -0.42 to 0.10; P = 0.23; I²: 42%), and major bleeding (overall OR = 1.25, 95%CI: 0.58-2.71; P = 0.56; I²: 0%) between the two procedures. These differences remained statistically non-significant in all sensitivity analyses.

CONCLUSION

POEM was effective in treating achalasia. Shorter and longer myotomy procedures provided similar therapeutic effects in terms of long-term effectiveness. In addition, shorter myotomy reduced the operative time.

Gastroesophageal Reflux after Peroral Endoscopic Myotomy: Myth or Reality?

Peroral endoscopic myotomy (POEM) is an accepted treatment for achalasia cardia (AC), and results are comparable to those of laparoscopic Heller myotomy (LHM). In recent years, several reports have confirmed higher incidence of gastroesophageal reflux (GER) following POEM. This review evaluates the current evidence regarding post-POEM GER, critically examines the potential contributing factors responsible for GER, limitations of the current available functional testing, and precautions and preventive measures, and provides future directions for research. Factors conclusively contributing to increased post-POEM GER include injury to the sling fibers of the lower esophageal sphincter, length of gastric myotomy > 2 cm, and others. Historically, these same factors have been implicated for development of GER after surgical (laparoscopic) myotomy. Although less invasive, optimal technique of POEM may be important to control post-POEM GER. Most post-POEM GER occurs during the immediate post-POEM period, is mild, and is easily treatable using proton-pump inhibitors. GER incidence plateaus at 2 years and is comparable to that after LHM. Patients should therefore be prescribed proton-pump inhibitors for at least 2 years. Antireflux procedures (ARPs) are infrequently required in these patients as the incidence of refractory GER is low. Novel ARPs have been recently described and are currently under evaluation. Conclusive diagnosis of GER is a clinical challenge. Most patients are asymptomatic, and GER is diagnosed only on abnormal esophageal acid exposure (EAE). Studies have demonstrated that current measures to diagnose GER are inadequate, inaccurate, and cannot differentiate between true GER and abnormal EAE due to food fermentation in the distal esophagus. The Lyon Consensus criteria should be implemented for confirmation of diagnosis of GER. Finally, the review recommends an evidence-based clinical algorithm for evaluation and management of post-POEM GER and provides guidelines for future research in this field.

Devices for esophageal function testing

BACKGROUND AND AIMS

Esophageal function testing is an integral component of the evaluation of refractory GERD and esophageal motility disorders. This review summarizes the current technologies available for esophageal function testing, including the functional luminal imaging probe (FLIP), high-resolution esophageal manometry (HRM), and multichannel intraluminal impedance (MII) and pH monitoring.

METHODS

We performed a MEDLINE, PubMed, and MAUDE database literature search to identify pertinent clinical studies through March 2021 using the following key words: esophageal manometry, HRM, esophageal impedance, FLIP, MII, and esophageal pH testing. Technical data were gathered from traditional and web-based publications, proprietary publications, and informal communications with pertinent vendors. The report was drafted, reviewed, and edited by the American Society for Gastrointestinal Endoscopy Technology Committee and approved by the Governing Board of the American Society for Gastrointestinal Endoscopy.

RESULTS

FLIP is a high-resolution impedance planimetry system used for pressure and dimension measurement in the esophagus, pylorus, and anal sphincter. FLIP provides complementary information to HRM for esophageal motility disorders, especially achalasia. The Chicago classification, based on HRM data, is a widely adopted algorithmic scheme used to diagnose esophageal motility disorders. MII detects intraluminal bolus movement and, combined with pH measurement or manometry, provides information on acid and non-acid gastroesophageal reflux and bolus transit in patients with refractory GERD and for preoperative evaluation for anti-reflux procedures.

CONCLUSIONS

Esophageal function testing techniques (FLIP, HRM, and MII-pH) have diagnostic and prognostic value in the evaluation of esophageal motility disorders and refractory GERD. Newer technologies and classification systems have enabled an increased understanding of these diseases.

Achalasia: Diagnosis, Management and Surveillance

Achalasia is a rare chronic esophageal motility disorder characterized by incomplete relaxation of the lower esophageal sphincter and abnormal peristalsis. This abnormal motor function leads to impaired bolus emptying and symptoms of dysphagia, regurgitation, chest pain, or heartburn. After an upper endoscopy to exclude structural causes of symptoms, the gold standard for diagnosis is high-resolution esophageal manometry. However, complementary diagnostic tools include barium esophagram and functional luminal impedance planimetry. Definitive treatments include pneumatic dilation, Heller myotomy with fundoplication, and peroral endoscopic myotomy.

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.

Comparison of preoperative, intraoperative, and follow-up functional luminal imaging probe measurements in patients undergoing myotomy for achalasia

BACKGROUND AND AIMS

The functional luminal imaging probe (FLIP) is a novel catheter-based device that measures esophagogastric junction (EGJ) distensibility index (DI) in real time. Previous studies have demonstrated DI to be a predictor of post-treatment clinical outcomes in patients with achalasia. We sought to evaluate EGJ DI in patients with achalasia before, during, and after peroral endoscopic myotomy (POEM) and laparoscopic Heller myotomy (LHM) and to assess the correlation of DI with postoperative outcomes.

METHODS

DI (defined as the minimum cross-sectional area at the EGJ divided by distensive pressure) was measured at 4 time points in patients undergoing surgical myotomy for achalasia: (1) during outpatient preoperative endoscopy (preoperative DI), (2) at the start of each operation after the induction of anesthesia (induction DI), (3) at the conclusion of each operation (postmyotomy DI), and (4) at routine follow-up endoscopy 12 months postoperatively (follow-up DI). Routine Eckardt symptom score, endoscopy, timed barium esophagram, and pH study were obtained 12 months postoperatively.

RESULTS

Forty-six patients (35 POEM, 11 LHM) underwent FLIP measurements at all 4 time points. Preoperative and induction mean DI were similar for both groups (POEM, 1 vs .9 mm²/mm Hg; LHM, 1.7 vs 1.5 mm²/mm Hg). POEM resulted in a significant increase in DI (induction .9 vs postmyotomy 7 mm²/mm Hg, P < .001). There was a subsequent decrease in DI in the follow-up period (postmyotomy 7 vs follow-up 4.8 mm²/mm Hg, P < .01), but DI at follow-up was still significantly improved from preoperative values (P < .001). For LHM patients, DI also increased as a result of surgery (induction 1.5 vs postmyotomy 5.9 mm²/mm Hg, P < .001); however, the increase was smaller than in POEM patients (DI increase 4.4 vs 6.2 mm²/mm Hg, P < .05). After LHM, DI also decreased in the follow-up period, but this change was not statistically significant (5.9 vs 4.4 mm²/mm Hg, P = .29). LHM patients with erosive esophagitis on follow-up endoscopy had a significantly higher postmyotomy DI compared with those without esophagitis (9.3 vs 4.8 mm²/mm Hg, P < .05).

CONCLUSIONS

EGJ DI improved dramatically as a result of both POEM and LHM, with POEM resulting in a larger increase. Mean DI decreased at intermediate follow-up but remained well above previously established thresholds for symptom recurrence. DI at the conclusion of LHM was predictive of erosive esophagitis in the postoperative period, which supports the potential use of FLIP for calibration of partial fundoplication construction during LHM.

Prospective evaluation of the efficacy of peroral endoscopic myotomy in patients with achalasia

Peroral endoscopic myotomy (POEM) is an endoscopic alternative to surgical myotomy in patients with achalasia. This study aimed to evaluate the efficacy and clinical outcomes of POEM.A total of 20 patients with achalasia who underwent POEM between October 2016 and November 2017 were prospectively recruited. The intraoperative esophagogastric junction distensibility index (mm2/mm Hg) was measured pre- and post-myotomy using an endoluminal functional lumen imaging probe. Clinical response was defined as Eckardt score ≤3. Health-related quality of life was measured by the 36-item short-form health survey score.POEM was successfully completed in all cases. The median procedure time was 68.5 minutes (range 50.0-120.0), and the median myotomy length was 13 cm (range 11-18). Major adverse events were encountered in 2 cases. Overall, clinical responses were observed in all patients during a median follow-up of 11.9 months (range 1.2-26.2). Postoperative esophagogastric junction distensibility index was significantly higher than baseline (from 1.3 [range 0.8-6.9] to 6.3 [range 25-19.2], P < .001). The median Eckardt scores were decreased after POEM (5 [range 2-11] to 1 [range 0-3], P < .001), and the 36-item short-form health survey score was also improved significantly after POEM (67.5 [range 34.5-93.9] to 85.7 [range 53.4-93.3], P = .004).POEM is an effective treatment for achalasia, based on the improvement of both symptoms and objective measures.Clinicaltrial.gov NCT02989883.

Impedance planimetry values for predicting clinical response following peroral endoscopic myotomy

BACKGROUND

There is growing interest in developing impedance planimetry as a tool to enhance the clinical outcomes for endoscopic and surgical management of achalasia. The primary aim of this study was to determine whether impedance planimetry measurements can predict clinical response and reflux following peroral endoscopic myotomy (POEM).

METHODS

A multicenter cohort study of patients with achalasia undergoing POEM was established from prospective databases and retrospective chart reviews. Patients who underwent impedance planimetry before and after POEM were included. Clinical response was defined as an Eckardt score of ≤ 3. Tenfold cross-validated area under curve (AUC) values were established for the different impedance planimetry measurements associated with clinical response and reflux development.

RESULTS

Of the 290 patients included, 91.7 % (266/290) had a clinical response and 39.4 % (108/274) developed reflux following POEM. The most predictive impedance planimetry measurements for a clinical response were: percent change in cross-sectional area (%ΔCSA) and percent change in distensibility index (%ΔDI), with AUCs of 0.75 and 0.73, respectively. Optimal cutoff values for %ΔCSA and %ΔDI to determine a clinical response were a change of 360 % and 272 %, respectively. Impedance planimetry values were much poorer at predicting post-POEM reflux, with AUCs ranging from 0.40 to 0.62.

CONCLUSION

Percent change in CSA and distensibility index were the most predictive measures of a clinical response, with a moderate predictive ability. Impedance planimetry values for predicting reflux following POEM showed weak predictive capacity.

Insights into the endoscopic management of esophageal achalasia

Achalasia is a primary esophageal motility disorder characterized by the loss of inhibitory neurons in the myenteric plexus, resulting in impaired relaxation of the esophagogastric junction. Achalasia is an incurable disease, and the treatment modalities are aimed at disruption of the esophagogastric junction and vary widely from pharmacological to endoscopic to surgical. Traditional endoscopic therapy includes pneumatic dilation, botulinum toxin injection, and peroral endoscopic myotomy. This review aims to provide an overview of the endoscopic management of achalasia, while focusing on the utilization of peroral endoscopic myotomy and other novel approaches.

Intraoperative diagnosis and treatment of Achalasia using EndoFLIP during Heller Myotomy and Dor fundoplication

BACKGROUND

Manometry is the gold standard diagnostic test for achalasia. However, there are incidences where manometry cannot be obtained preoperatively, or the results of manometry is inconsistent with the patient's symptomatology. We aim to determine if intraoperative use of EndoFLIP can provide a diagnosis of achalasia and provide objective information during Heller myotomy and Dor fundoplication.

METHODS

To determine the intraoperative diagnostic EndoFLIP values for patients with achalasia, we determined the optimal cut-off points of the distensibility index (DI) between patients with a diagnosis of achalasia and patients with a diagnosis of hiatal hernia. To evaluate the usefulness of EndoFLIP values during Heller myotomy and Dor fundoplication, we obtained a cohort of patients with EndoFLIP values obtained after Heller myotomy and after Dor fundoplication as well as Eckardt score before and after surgery.

RESULTS

Our analysis of 169 patients (133 hiatal hernia and 36 achalasia) showed that patients with DI < 0.8 have a >99% probability of having achalasia, while DI > 2.3 have a >99% probability of having hiatal hernia. Patients with a DI 0.8-1.3 have a 95% probability of having achalasia, and patients with a DI of 1.4-2.2 have a 94% probability of having a hiatal hernia. There were 40 patients in the cohort to determine objective data during Heller myotomy and Dor fundoplication. The DI increased from a median of 0.7 to 3.2 after myotomy and decreased to 2.2 after Dor fundoplication (p < 0.001). The median Eckardt score went down from a median of 4.5 to 0 (p < 0.001).

CONCLUSIONS

Our study shows that intraoperative use of EndoFLIP can facilitate the diagnosis of achalasia and is used as an adjunct to diagnose achalasia when symptoms are inconsistent. The routine use of EndoFLIP during Heller myotomy and Dor fundoplication provides objective data during the operation in a group of patients with excellent short-term outcomes.

[Diagnosis of Dysphagia: High Resolution Manometry & EndoFLIP]

Esophageal motility disorders were re-defined when high-resolution manometry was employed to better understand their pathogenesis. Newly developed parameters including integrated relaxation pressure (IRP), distal contractile integral, and distal latency showed better diagnostic yield compared with previously used conventional parameters. Therefore, Chicago classification was formulated, and its diagnostic cascade begins by assessing the IRP value. However, IRP showed limitation due to its inconsistency, and other studies have tried to overcome this. Recent studies showed that provocative tests, supplementing the conventional esophageal manometry protocol, have improved the diagnostic yield of the esophageal motility disorders. Therefore, position change from supine to upright, solid or semi-solid swallowing, multiple rapid swallows, and the rapid drink challenge were newly added to the manometry protocol in the revised Chicago classification version 4.0. Impedance planimetry enables measurement of bag cross-sectional area at various locations. The functional lumen imaging probe (FLIP) has been applied to assess luminal distensibility. This probe can also measure pressure, serial cross-sectional areas, and tension-strain relationship. The esophagogastric junction's distensibility is decreased in achalasia. Therefore, EndoFLIP can be used to assess contractility and distensibility of the esophagus in the patients with achalasia, including repetitive antegrade or retrograde contractions. EndoFLIP can detect achalasia patients with relatively low IRP, which was difficult to diagnose using the current high-resolution manometry. EndoFLIP also provides information on the contractile activity and distensibility of the esophageal body in patients with achalasia. The use of provocative tests, newly added in Chicago classification 4.0 version, and EndoFLIP can expand understanding of esophageal motility disorders.

Clinical utility of cricopharyngeal distensibility measurements during endoscopic myotomy for Zenker's diverticulum

BACKGROUND AND AIMS

Flexible endoscopic cricopharyngeal myotomy (FECM) allows minimally invasive treatment of patients with Zenker's diverticulum (ZD); however, retreatment rates are substantial. We hypothesized that the functional lumen imaging probe (FLIP) may provide insight into ZD pathophysiology and serve as an intraprocedural guide to adequacy of myotomy.

METHODS

We prospectively evaluated 11 ZD patients undergoing FECM and compared the baseline cricopharyngeal (CP) distensibility with 16 control subjects. Intraprocedural CP distensibility was measured immediately pre- and postmyotomy. The CP distensibility index (CP-DI) was defined as a ratio of the narrowest cross-sectional area (nCSA) and the corresponding intrabag pressure at 40 mL distension. Same-procedure myotomy extension was undertaken in a subgroup if threshold distensibility changes were not met.

RESULTS

ZD patients had reduced baseline nCSA and CP-DI compared with control subjects, (169.6 vs 227.5 mm² [P < .001] and 3.8 vs 7.6 mm²/mm Hg [P < .001], respectively). After CP myotomy, both nCSA and CP-DI increased significantly by an average of 74.2 mm² (95% confidence interval [CI], 35.1-113.3; P = .002) and 2.2 mm²/mm Hg (95% CI, .6-3.8; P = .01), respectively. In the subgroup with no significant change in CP distensibility after initial myotomy (n = 6), myotomy extension resulted in significant increases in both mean nCSA and CP-DI of 66.6 mm² (95% CI, 16.4-116.8; P = .03) and 1.9 mm²/mm Hg (95% CI, .4-3.3; P = .015), respectively. There were no adverse events.

CONCLUSIONS

CP distensibility is reduced in ZD patients and is partially reversible by FECM. An intraprocedural FLIP CP distensibility measurement is safe and sensitive in detecting myotomy-induced changes. These findings support using FLIP to optimize FECM outcome. Further studies are required to derive precise metrics predictive of clinical response.

Use of the Functional Lumen Imaging Probe in Clinical Esophagology

The functional lumen imaging probe (FLIP) measures luminal dimensions using impedance planimetry, performed most often during sedated upper endoscopy. Mechanical properties of the esophageal wall and opening dynamics of the esophagogastric junction (EGJ) can be objectively evaluated in esophageal motor disorders, eosinophilic esophagitis, esophageal strictures, during esophageal surgery and in postsurgical symptomatic states. Distensibility index, the ratio of EGJ cross sectional area to intraballoon pressure, is the most useful FLIP metric. Secondary peristalsis from balloon distension can be displayed topographically as repetitive anterograde or retrograde contractile activity in the esophageal body, similar to high-resolution manometry. Real-time interpretation and postprocessing of FLIP metadata can complement the identification of esophageal outflow obstruction and achalasia, especially when findings are inconclusive from alternate esophageal tests in symptomatic patients. FLIP can complement the diagnosis of achalasia when manometry and barium studies are inconclusive or negative in patients with typical symptoms. FLIP can direct adequacy of disruption of the EGJ in achalasia when used during and immediately after myotomy and pneumatic dilation. Lumen diameter measured using FLIP in eosinophilic esophagitis and in complex strictures can potentially guide management. An abbreviated modification of the Grading of Recommendations Assessment, Development, and Evaluation was used to determine the quality of available evidence and recommendations regarding FLIP utilization. FLIP metrics that are diagnostic or suggestive of an abnormal motor pattern and metrics that define normal esophageal physiology were developed by consensus and are described in this review.

ACG Clinical Guidelines: Clinical Use of Esophageal Physiologic Testing

Esophageal symptoms are common and may indicate the presence of gastroesophageal reflux disease (GERD), structural processes, motor dysfunction, behavioral conditions, or functional disorders. Esophageal physiologic tests are often performed when initial endoscopic evaluation is unrevealing, especially when symptoms persist despite empiric management. Commonly used esophageal physiologic tests include esophageal manometry, ambulatory reflux monitoring, and barium esophagram. Functional lumen imaging probe (FLIP) has recently been approved for the evaluation of esophageal pressure and dimensions using volumetric distension of a catheter-mounted balloon and as an adjunctive test for the evaluation of symptoms suggestive of motor dysfunction. Targeted utilization of esophageal physiologic tests can lead to definitive diagnosis of esophageal disorders but can also help rule out organic disorders while making a diagnosis of functional esophageal disorders. Esophageal physiologic tests can evaluate obstructive symptoms (dysphagia and regurgitation), typical and atypical GERD symptoms, and behavioral symptoms (belching and rumination). Certain parameters from esophageal physiologic tests can help guide the management of GERD and predict outcomes. In this ACG clinical guideline, we used the Grading of Recommendations Assessment, Development and Evaluation process to describe performance characteristics and clinical value of esophageal physiologic tests and provide recommendations for their utilization in routine clinical practice.

Functional Luminal Imaging Probe Panometry Identifies Achalasia-Type Esophagogastric Junction Outflow Obstruction

BACKGROUND & AIMS

The etiologies of esophagogastric junction outflow obstruction (EGJOO) vary, as do their therapeutic implications. We aimed to identify patients with EGJOO most likely to benefit from achalasia-type treatment, based on findings from functional luminal imaging probe (FLIP) panometry.

METHODS

We performed a retrospective study of 34 patients who received a diagnosis of EGJOO from January 2015 through July 2017. Our analysis included patients who had been evaluated with timed barium esophagram, FLIP, or upper endoscopy.

RESULTS

Among the 34 patients with idiopathic EGJOO, 7 (21%) had a normal esophagogastric junction distensibility index (EGJ-DI), based on FLIP panometry, and all had repetitive antegrade contractions. None of the patients had radiographic evidence of EGJOO (RAD-EGJOO), defined as liquid barium retention and/or barium tablet impaction. On the other hand, all 18 patients with RAD-EGJOO had an EGJ-DI less than 2 mm²/mm Hg. Nine of the 18 patients with RAD-EGJOO and EGJ-DI less than 2 mm²/mm Hg underwent achalasia-type treatment, and 77.8% of these (7 of 9) had improvements in Eckardt score. Of the 6 patients with a normal EGJ-DI (>3 mm²/mm Hg) who were treated conservatively and followed up, 100% had improvements in subsequent Eckardt scores.

CONCLUSIONS

We found that FLIP is useful in identifying patients with EGJOO who are most likely to benefit from achalasia-type therapy. Patients with a low EGJ-DI responded well to achalasia-type treatment, whereas patients with normal results from FLIP panometry had good outcomes from conservative management. FLIP panometry might help select management strategies for this difficult population of patients.

The use of impedance planimetry (Endoscopic Functional Lumen Imaging Probe, EndoFLIP® ) in the gastrointestinal tract: A systematic review

BACKGROUND AND PURPOSE

The EndoFLIP® system is a method of delineating impedance and was first designed to investigate the characteristics of the esophago-gastric junction. In the last decade, its use was widened to investigate other sphincteric and non-sphincteric systems of the gastrointestinal tract. The objective of the present systematic review was to summarize the available data in literature on the use of the EndoFLIP® system in the gastrointestinal tract, including sphincteric and non-sphincteric regions. We performed a systematic review in accordance with recommendations for systematic review using PRISMA guidelines without date restriction, until June 2020, using MEDLINE-PubMed, Cochrane Library, and Google Scholar databases. Only articles written in English were included in the present review. Five hundred and six unique citations were identified from all database combined. Of those, 95 met the inclusion criteria. There was a lack of standardization among studies in terms of anesthetic drugs use, probe placement, and inflation protocol. In most cases, only small cohorts of patients were included. Most studies investigated the EGJ, with a potential use of the EndoFLIP® to identify a subgroup of patients with achalasia and for intraoperative assessment of treatment efficacy in achalasia. However, the use of EndoFLIP® in the esophageal body (esophageal panometry), other esophageal diseases (gastro-esophageal reflux disease, eosinophilic esophagitis), and other sphincter regions (anal canal, pylorus) will need further confirmatory studies. The EndoFLIP® system provides detailed geometric data of the gastrointestinal lumen but further works are needed to determine its use in clinical practice.

Esophageal Functional Lumen Imaging Probe (FLIP): How Can FLIP Enhance Your Clinical Practice?

Recent innovations in esophageal diagnostic testing have enhanced gastroenterology clinical practice by facilitating more nuanced and advanced evaluation of esophageal symptoms. Among these pivotal advances is the FDA-approved functional lumen imaging probe (FLIP), which utilizes impedance planimetry via volumetric distension of a catheter-mounted balloon at the time of sedated upper endoscopy, to acquire esophageal dimensions and pressures. In real time, FLIP can display cross-sectional areas (CSA) and distensibility indices (ratios of CSA to intra-balloon pressures) throughout the esophagus, most notably at the esophagogastric junction, as well as secondary peristaltic esophageal body contractile patterns. As the use of FLIP has progressively spread and permeated into the practice of clinical gastroenterology since its introduction, increasing data on and experiences with its applications have accumulated to guide its utility in clinical practice. In this current review developed for gastroenterologists and foregut surgeons across clinical practice, we provide an introduction to FLIP technology and metrics and discuss the clinical scenarios in which performance of or referral for FLIP may be helpful in the evaluation and management of patients with commonly encountered esophageal symptoms and disorders. Specifically, we discuss the potential applications and limitations of FLIP as a complementary diagnostic modality in patients with non-obstructive dysphagia, established or suspected achalasia spectrum disorders, eosinophilic esophagitis, gastroesophageal reflux disease and those undergoing esophageal surgery.

The functional lumen imaging probe in gastrointestinal disorders: the past, present, and future

The functional lumen imaging probe (FLIP) is a diagnostic tool that utilizes impedance planimetry to allow the assessment of luminal diameter and distensibility. It has been used primarily in esophageal diseases, in particular, in the assessment of achalasia, esophagogastric junction outflow obstruction, and eosinophilic esophagitis (EoE). The usage and publications have increased over the past decade and it is now an essential tool in the armamentarium of the esophagologist. Indications are emerging outside of the esophagus, in particular with regard to gastroparesis. Our paper will review the history of FLIP, optimal current usage, data for key esophageal disorders (including achalasia, reflux, and EoE), data for nonesophageal disorders, and our sense as to whether FLIP is ready for prime time, as well as gaps in evidence and suggestions for future research.