Efficacy of treatment for patients with achalasia depends on the distensibility of the esophagogastric junction

Delta-integrated relaxation pressures as a new high-resolution manometry metric to predict the positive outcome of laparoscopic Heller-Dor in patients with achalasia

BACKGROUND

There is no consensus on the definition of failure after treatment in patients with achalasia. The Eckardt score is used to define clinical outcomes. However, objective metrics are lacking. This study aimed to identify whether any high-resolution manometry (HRM) parameters may be useful in predicting a positive outcome after laparoscopic Heller-Dor (LHD).

METHODS

Patients who underwent LHD between 2012 and 2022 were enrolled. The patients were divided according to the outcome: the success group (SG) and the failure group (FG). In addition to the common HRM parameters, we measured the difference between pre- and postoperative integrated relaxation pressures (∆-IRPs). A receiver operating characteristic (ROC) curve analysis was performed to assess the accuracy of each HRM parameter.

RESULTS

Of note, 336 patients (92.3%) were classified in the SG, and 28 patients (7.7%) were classified in the FG. No difference was found in terms of manometric types, symptom duration, and history of previous treatments. Preoperative lower esophageal sphincter (LES) pressure and IRP were higher in the SG than in the FG (41 vs 35 mm Hg [P =.03] and 33 vs 26 mm Hg [P =.002], respectively). The postoperative LES metrics were similar between the 2 groups, except for the ∆-IRP that was higher in the SG (23 mm Hg [IQR, 15-31]) than in the FG (14 mm Hg [IQR, 9-17]) (P =.0002). In the univariate analysis, age, LES preoperative pressure, IRP, and ∆-IRP were factors able to predict a positive clinical outcome. In the multivariate analysis, the ∆-IRP was the only parameter independently related to clinical success (odds ratio, 0.94; 5%-95% CI, 0.89-0.99). The ROC curve for the ∆-IRP showed an area under the curve of 0.71, with a threshold value set at 16.5 mm Hg (sensibility of 71% and specificity of 70%).

CONCLUSION

Our data showed that the ∆-IRP with a threshold of 16.5 mm Hg could represent a new objective tool for predicting the long-term positive outcome of LHD in patients with esophageal achalasia.

The history and use of the timed barium esophagram in achalasia, esophagogastric junction outflow obstruction, and esophageal strictures

BACKGROUND

Dysphagia is one of the most common complaints that gastroenterologists encounter in the outpatient setting. To evaluate this common complaint, patients are often sent for a barium esophagram, a test that is widely available, inexpensive, and easy to perform. This simple test provides a reliable method to evaluate esophageal anatomy and structural abnormalities.

PURPOSE

This narrative reviews the history of the development and validation of the timed-barium esophagram (TBE), along with its strengths and limitations, and discusses its use in the pre- and posttreatment assessment of patients with achalasia, esophagogastric junction outflow obstruction (EGJOO), and esophageal strictures. Providing excellent anatomic detail of the esophagus and an accurate assessment of esophageal emptying, over time, the TBE has become part of the standard workup in our Swallowing Center for patients with dysphagia.

Diagnostic and therapeutic strategies for achalasia of the cardia

The diagnosis of achalasia of the cardidia (AC) is primarily based on clinical symptoms, esophagographic findings, esophagodynamic examination, and upper gastrointestinal endoscopic findings. High resolution manometry is considered the gold standard for diagnosis. With the advan-cement of new technologies, the diagnostic methods for AC have become more diverse, and three-dimensional modeling may facilitate early detection of AC. The use of endoscopic functional intracavity imaging probe can enhance diagnostic accuracy. Common treatment options include endoscopic balloon dilation, laparoscopic Heller myotomy, and peroral endoscopic myotomy (POEM). POEM has emerged as the most widely utilized therapeutic approach currently, significantly improving the clinical success rate in treating AC. This article provides a comprehensive review on recent research progress in the diagnosis and treatment of AC.

Functional lumen imaging probe use in a high-volume practice: Practical and technical implications

BACKGROUND

The functional lumen imaging probe (FLIP) is a Food and Drug Administration approved tool to aid the diagnosis and management of esophageal disorders. However, widespread adoption of FLIP remains limited and its utility in high-volume practices remains unclear.

AIM

To analyze large sample data on clinical use of FLIP and provide insight on several technical aspects when performing FLIP.

METHODS

We conducted a retrospective comparative and descriptive analysis of FLIP procedures performed by a single provider at an academic medical center. There was a total of 398 FLIP procedures identified. Patient medical records were reviewed and data regarding demographics and procedural details were collected. Statistical tests, including chi-squared, t-test, and multivariable logistic and linear regression, were performed.

RESULTS

There was an increase in FLIP cases with each successive time period of 13 months (n = 68, 146, 184, respectively) with notable rises specifically for indications of dysphagia and gastroesophageal reflux disease. There was a shift toward use of the longer FLIP balloon catheter for diagnostic purposes (overall 70.4% vs 29.6%, P < 0.01). Many cases (42.8%) were performed in conjunction with other diagnostics/interventions, such as dilation and wireless pH probe placement. Procedures were nearly equally performed with anesthesia vs moderate sedation (51.4% anesthesia), with no major complications. Patients who had anesthesia were less likely to have recurrent antegrade contractions [odds ratio (OR) = 0.4, 95%CI: 0.3-0.8] and were also more likely to have absent contractility (OR = 2.4, 95%CI: 1.3-4.4).

CONCLUSION

FLIP cases have increased in our practice with expanding indications for its use. Given limited normative data, providers should be aware of several potential technical issues, including the possible impact of sedation choice when assessing esophageal motility patterns.

Automatic three-dimensional reconstruction of the oesophagus in achalasia patients undergoing POEM: an innovative approach for evaluating treatment outcomes

BACKGROUND AND AIMS

Peroral endoscopic myotomy (POEM) is a standard treatment option for achalasia patients. Treatment response varies due to factors such as achalasia type, degree of dilatation, pressure and distensibility indices. We present an innovative approach for treatment response prediction based on an automatic three-dimensional (3-D) reconstruction of the tubular oesophagus (TE) and the lower oesophageal sphincter (LES) in patients undergoing POEM for achalasia.

METHODS

A software was developed, integrating data from high-resolution manometry, timed barium oesophagogram and endoscopic images to automatically generate 3-D reconstructions of the TE and LES. Novel normative indices for TE (volume×pressure) and LES (volume/pressure) were automatically integrated, facilitating pre-POEM and post-POEM comparisons. Treatment response was evaluated by changes in volumetric and pressure indices for the TE and the LES before as well as 3 and 12 months after POEM. In addition, these values were compared with normal value indices of non-achalasia patients.

RESULTS

50 treatment-naive achalasia patients were enrolled prospectively. The mean TE index decreased significantly (p<0.0001) and the mean LES index increased significantly 3 months post-POEM (p<0.0001). In the 12-month follow-up, no further significant change of value indices between 3 and 12 months post-POEM was seen. 3 months post-POEM mean LES index approached the mean LES of the healthy control group (p=0.077).

CONCLUSION

3-D reconstruction provides an interactive, dynamic visualisation of the oesophagus, serving as a comprehensive tool for evaluating treatment response. It may contribute to refining our approach to achalasia treatment and optimising treatment outcomes.

TRIAL REGISTRATION NUMBER

22-0149.

Effect of esophageal body recoil on clinical outcomes in non-spastic achalasia

BACKGROUND

Despite the established efficacy of achalasia treatments on symptomatic outcomes, there are limited data evaluating the treatment effect on esophageal dilatation. This study aimed to assess the effect achalasia treatment on esophageal dilatation and the effect of esophageal width reduction ("recoil") on clinical outcomes.

METHODS

Patients with type I or type II achalasia that completed high-resolution manometry (HRM), functional lumen imaging probe (FLIP), and timed barium esophagram (TBE) pre and post treatment were included. Esophageal width was measured using TBE. Focused subgroup analysis was performed on patients with normal posttreatment EGJ opening on FLIP. Good clinical outcomes were defined as barium column height of <5 cm at 5 min and Eckardt Score ≤3.

KEY RESULTS

Sixty-nine patients (41% type I and 59% type II) were included. Esophageal width decreased from pre to post treatment mean (SD) 4.2 (1.3) cm-2.8 (1.2) cm; p < 0.01. In the normal post treatment EGJ opening subgroup, esophageal width was less in patients with good TBE outcome compared to poor outcome mean (SD) 2.2 (0.7) cm versus 3.2 (1.4) cm (p < 0.01), but did not differ in good versus poor symptomatic outcome groups. Esophageal width recoil >25% posttreatment was associated with a greater rate of good TBE outcome (71% vs. 50%, p = 0.04) and good symptomatic outcome (88% vs. 50%; p = 0.04).

CONCLUSIONS AND INFERENCES

Esophageal recoil was associated with good achalasia treatment outcome in patients without posttreatment EGJ obstruction. This suggests that mechanical properties of the esophageal wall, likely associated with tissue remodeling, play a role in clinical outcomes following achalasia treatment.

Active narcotic use and post-peroral endoscopic myotomy outcomes in esophageal motility disorders

BACKGROUND AND AIMS

Peroral endoscopic myotomy (POEM) is a minimally invasive technique used to treat esophageal motility disorders. Opioid use has been demonstrated to adversely affect esophageal dysmotility and is associated with an increased prevalence of esophageal motility disorders. Our aim was to investigate the effect of narcotic use on success rates in patients undergoing POEM.

METHODS

This was a single-center, retrospective study of patients undergoing POEM between February 2017 and September 2021. Primary outcomes were post-POEM Eckardt score (ES), distensibility index, and length of procedure. Secondary outcomes included technical success, myotomy length, length of stay, adverse events, reintervention rates, and postprocedure GERD.

RESULTS

During the study period, 90 patients underwent POEM for treatment of esophageal dysmotility disorders. Age, sex, race, indications for POEM, and body mass index were not significant between those with or without narcotic use. There were no differences in procedure time, preprocedure ESs, or length of stay. Postprocedure ESs were higher in the group with active narcotic use compared to the group with no prior history (2.73 vs 1.2, P = .004). Distensibility indexes measured with EndoFLIP (Medtronic, Minneapolis, Minn, USA) were not different in patients using narcotics compared with opioid-naïve patients.

CONCLUSION

Active narcotic use negatively affects symptom improvement after POEM for the treatment of esophageal motility disorders.

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.

An overview of the efficacy, safety, and predictors of achalasia treatments

INTRODUCTION

Achalasia is a rare esophageal motility disorder characterized by abnormal esophageal peristalsis and the inability of the lower esophageal sphincter to relax, resulting in poor esophageal emptying. This can be relieved by endoscopic and surgical treatments; each comes with certain advantages and disadvantages.

AREAS COVERED

This review aims to guide the clinician in clinical decision making on the different treatment options for achalasia regarding the efficacy, safety, and important predictors.

EXPERT OPINION

Botulinum toxin injection is only recommended for a selective group of achalasia patients because of the short term effect. Pneumatic dilation improves achalasia symptoms, but this effect diminishes over time and requiring repeated dilations to maintain clinical effect. Heller myotomy combined with fundoplication and peroral endoscopic myotomy are highly effective on the long term but are more invasive than dilations. Gastro-esophageal reflux complaints are more often encountered after peroral endoscopic myotomy. Patient factors such as age, comorbidities, and type of achalasia must be taken into account when choosing a treatment. The preference of the patient is also of great importance and therefore shared decision making has to play a fundamental role in deciding about treatment.

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.

Relaxation of the lower esophageal sphincter in response to reduced volume distension during FLIP Panometry

BACKGROUND

The esophageal response to stepwise distension during the functional lumen imaging probe (FLIP) Panometry study often parallels high-resolution manometry (HRM) motility diagnoses. This study aimed to describe the changes in FLIP metrics during FLIP emptying, that is, reduced volume distension.

METHODS

Adult patients who completed FLIP and HRM for esophageal motility evaluation were included. Esophagogastric junction (EGJ) opening parameters were assessed during stepwise FLIP filling to volumes of 60 mL ("filling 60 mL"), then 70 mL, and then back to 60 mL ("emptying 60 mL"). HRM studies were analyzed per Chicago classification version 4.0 (CCv4.0).

KEY RESULTS

Among 265 patients included, HRM/CCv4.0 diagnoses included achalasia in 80 patients (30%), normal motility in 70 (26%), and ineffective esophageal motility (IEM) in 43 (16%). EGJ-distensibility index (DI) and EGJ diameter were greater during emptying 60 mL than filling 60 mL in achalasia, normal motility, and IEM (p values <0.002). If applying the emptying 60 mL EGJ-DI (vs. filling 60 mL EGJ-DI), EGJ opening classification changed from reduced EGJ opening to borderline EGJ opening in 31% of achalasia patients and in 2% of patients with normal motility or IEM. EGJ opening classification was unchanged in 69% achalasia and 96% of normal motility/IEM.

CONCLUSIONS AND INFERENCES

This study suggests that isotonic or auxotonic relaxation of the lower esophageal sphincter occurs with reduced volume distension in patients with achalasia and normal motility. The study also supports the importance of utilizing a standardized FLIP motility study protocol (i.e., controlled, stepwise filling to 50 mL, 60 mL, then 70 mL) to provide reliable and generalizable FLIP metrics to facilitate diagnosis of esophageal motility disorders.

Impaired sliding between the lower esophageal sphincter and crural diaphragm (esophageal hiatus) in patients with achalasia esophagus

Swallow-related axial shortening of the esophagus results in the formation of phrenic ampulla in normal subjects; whether it is the case in achalasia esophagus is not known. The goal is to study axial shortening of the esophagus and relative movement between the lower esophageal sphincter (LES) and crural diaphragm (CD) in normal subjects and patients with achalasia. A novel method, isoimpedance contour excursion at the lower edger of LES, as a marker of axial esophageal shortening was validated using X-ray fluoroscopy (n = 5) and used to study axial shortening and separation between the LES and CD during peristalsis in normal subjects (n = 15) and patients with achalasia type 2 esophagus (n = 15). Abdominal CT scan images were used to determine the nature of tissue in the esophageal hiatus of control (n = 15) and achalasia patients (n = 15). Swallow-induced peristalsis resulted in an axial excursion of isoimpedance contours, which was quantitatively similar to the metal clip anchored to the LES on X-ray fluoroscopy (2.3 ± 1.4 vs. 2.1 ± 1.4 cm with deep inspiration and 2.7 ± 0.6 cm vs. 2.7 ± 0.6 cm with swallow-induced peristalsis). Esophageal axial shortening with swallows in patients with achalasia was significantly smaller than normal (1.64 ± 0.5 cm vs. 3.59 ± 0.4 cm, P < 0.001). Gray-level matrix analysis of CT images suggests more "fibrous" and less fat in the hiatus of patients with achalasia. Lack of sliding between the LES and CD explains the low prevalence of hiatus hernia, and low compliance of the LES in achalasia esophagus, which likely plays a role in the pathogenesis of achalasia.NEW & NOTEWORTHY Swallow-related axial shortening of the esophagus is reduced, and there is no separation between the lower esophageal sphincter and crural diaphragm (CD) with swallowing in patients with achalasia esophagus. Fat in the hiatal opening of the esophagus appears to be replaced with fibrous tissue in patients with achalasia, resulting in tight anchoring between the LES and CD. The above findings explain low prevalence of hiatus hernia and the low compliance of the LES in achalasia esophagus.

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.

Development and Evaluation of a Flexible PVDF-Based Balloon Sensor for Detecting Mechanical Forces at Key Esophageal Nodes in Esophageal Motility Disorders

Prevailing methods for esophageal motility assessments, such as perfusion manometry and probe-based function imaging, frequently overlook the intricate stress fields acting on the liquid-filled balloons at the forefront of the probing device within the esophageal lumen. To bridge this knowledge gap, we innovatively devised an infusible flexible balloon catheter, equipped with a quartet of PVDF piezoelectric sensors. This design, working in concert with a bespoke local key-node analytical algorithm and a sensor array state analysis model, seeks to shed new light on the dynamic mechanical characteristics at pivotal esophageal locales. To further this endeavor, we pioneered a singular closed balloon system and a complementary signal acquisition and processing system that employs a homogeneously distributed PVDF piezoelectric sensor array for the real-time monitoring of dynamic mechanical nuances in the esophageal segment. An advanced analytical model was established to scrutinize the coupled physical fields under varying degrees of balloon inflation, thereby facilitating a thorough dynamic stress examination of local esophageal nodes. Our rigorous execution of static, dynamic, and simulated swallowing experiments robustly substantiated the viability of our design, the logical coherence of our esophageal key-point stress analytical algorithm, and the potential clinical utility of a flexible esophageal key-node stress detection balloon probe outfitted with a PVDF array. This study offers a fresh lens through which esophageal motility testing can be viewed and improved upon.

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.

Peroral Endoscopic Myotomy: What Nurses Need to Know to Provide Preeminent Perioperative Care

This article aims to explore details of research, evidence, and key concepts intended for nurses and other healthcare clinicians surrounding the paradigm shift in therapeutic endoscopy relating to the third-space endoscopic procedure, peroral endoscopic myotomy. Although many medical publications detail the procedure, there are no specific guidelines for nurses to reference when caring for the patient undergoing peroral endoscopic myotomy. With scant published resources available to direct nurses distinctly in the delivery of exceptional care to patients undergoing peroral endoscopic myotomy, there is an identified need for collated information to be accessible to all nurses providing perioperative teaching and care. As peroral endoscopic myotomy continues to transpire as a mainstream or preferred standard treatment for patients who suffer from achalasia, relevant education remains to be fully understood and assessed in the nursing arena. By examining nursing considerations for patient care, indications, techniques, and advancements regarding this ever-emergent breakthrough, readers will discover guidance in comprehensive care encompassing patients undergoing the peroral endoscopic myotomy procedure.

Update on the Diagnosis and Treatment of Achalasia

Achalasia is a rare disease of the esophagus with impaired relaxation of the lower esophageal sphincter and aperistalsis. The etiology is unknown but speculations include a viral or autoimmune etiology. All specialists dealing with swallowing and esophageal diseases should recognize the classic symptoms of dysphagia for solids/liquids, regurgitation, and choking, especially at night. High-resolution manometry is critical for the diagnosis with endoscopy and barium esophagram having a supportive role. The disease cannot be cured but most can return to near normal swallowing and a regular diet with appropriate therapy. Treatment includes smooth muscle relaxants, botulinum toxin injections to the lower sphincter, pneumatic dilation, Heller myotomy, and peroral endoscopic myotomy. One treatment does not fit all and a tailored approach through a multidiscipline team will give the best long-term outcomes.

Rapid Drink Challenge During High-resolution Manometry for Evaluation of Esophageal Emptying in Treated Achalasia

BACKGROUND & AIMS

Incomplete esophageal emptying is a key variable predicting symptom relapse after achalasia treatment. Although optimally evaluated using the timed barium esophagogram (TBE), incomplete esophageal emptying can also be identified on rapid drink challenge (RDC) performed during high-resolution manometry.

METHODS

We evaluated if RDC differentiates complete from incomplete esophageal emptying in treated patients with achalasia, against a TBE gold standard. Unselected treated patients with achalasia with both TBE (200 mL of low-density barium suspension) and RDC (200 mL of water in sitting position) were enrolled in 5 tertiary referral centers. TBE barium column height at 1, 2, and 5 minutes were compared with RDC variables: pressurizations >20 mmHg, maximal RDC pressurization, proportion of RDC time occupied by pressurizations, trans-esophagogastric junction gradient, and integrated relaxation pressure.

RESULTS

Of 175 patients recruited (mean age, 59 years; 47% female), 138 (79%) were in clinical remission. Complete TBE emptying occurred in 45.1% at 1 minute, 64.0% at 2 minutes, and 73.1% at 5 minutes. RDC integrated relaxation pressure correlated strongly with TBE column height, and a 10-mmHg threshold discriminated complete from incomplete emptying at all 3 TBE time points with area under receiver operating characteristic curves of 0.85, 0.87, and 0.85, respectively. This threshold had high negative predictive values for complete emptying (88% at 2 minutes, 94% at 5 minutes), and modest positive predictive values for incomplete emptying (77% at 2 minutes, 62% at 5 minutes).

CONCLUSIONS

RDC during high-resolution manometry is an effective surrogate for TBE in assessing esophageal emptying in treated patients with achalasia.

Chronic opioid users with dysphagia are indistinguishable from symptomatic nonusers on functional lumen imaging probe evaluation

BACKGROUND

Opioid-induced esophageal dysmotility (OIED) includes spastic esophageal motility disorders, increasingly recognized in the contemporary opioid epidemic. We assessed functional lumen imaging probe (FLIP) findings in diagnosing OIED.

METHODS

Symptomatic patients undergoing FLIP with no prior foregut surgery who completed validated questionnaires were identified and segregated into chronic opioid users and nonusers in this cohort study. Esophagogastric junction (EGJ) distensibility index (DI), EGJ diameter, and esophageal body contraction patterns were extracted. Symptom profiles were compared to FLIP findings between chronic opioid users and nonusers. Outcome was evaluated in a subset using the same validated questionnaires.

RESULTS

Over the 18-months study period, of 116 patients (median age 62 years, 70.7% female), 33 (28.4%) were chronic opioid users, with median morphine milligram equivalent of 30 mg. While presenting symptoms were similar, chronic opioid users reported higher perceptive symptoms (p = 0.008) and worse quality of life (p = 0.01) compared to nonusers. Median DI trended lower in chronic opioid users (p = 0.08), with more retrograde repetitive contractions (p < 0.001) and less absent contractility (p = 0.007), but final FLIP diagnoses were similar compared to nonusers. There was no correlation between opioid dose and FLIP metrics. In the subset with follow-up, perceptive symptoms trended higher in chronic opioid users (p = 0.08), but symptom improvement following therapy was similar in both groups.

CONCLUSIONS & INFERENCES

Symptomatic chronic opioid users have FLIP diagnoses that are similar to nonusers, despite higher perceptive symptoms and worse quality of life. Dominant symptoms improve both in chronic opioid users and nonusers following treatment directed by FLIP.

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.

Normative values for esophageal functional lumen imaging probe measurements: A meta-analysis

BACKGROUND

The functional lumen imaging probe (Endoflip™) is increasingly used for evaluation of patients with esophageal symptoms. To improve the interpretation of Endoflip™ in clinical practice, normative values with appropriate cut-off values are required.

METHODS

Original clinical studies describing Endoflip™ use for measurements of esophageal motility in healthy adults were considered. Meta-analysis was performed based on published values.

RESULTS

A total of 17 articles were included in the systematic review, 15 of which were included in the meta-analysis, representing 154 unique subjects. At 40 ml distention, the 5th-95th and 10th-90th percentiles for esophagogastric junction distensibility index (EGJ-DI) were 1.96-10.95 mm² /mmHg and 2.36-8.95 mm² /mmHg, respectively. An EGJ-DI below 2 mm² /mmHg was found in 5.4%, and below 3 mm² /mmHg in 20.1% of healthy subjects. At 50 ml distention, the 5th-95th and 10th-90th percentiles for EGJ-DI are 2.86-10.66 mm² /mmHg and 3.28-9.12 mm² /mmHg, respectively (below 2 mm² /mmHg: 0.6%, 3 mm² /mmHg: 6.3%). The 5th-95th and 10th-90th percentiles for EGJ-DI at 60 ml distention were 3.06-8.14 mm² /mmHg and 3.33-7.18 mm² /mmHg, respectively (below 2 mm² /mmHg: 0.0%, 3 mm² /mmHg: 7%). A clear cut-off for lower values was identified while a large spread in values was observed for upper limits of normal for EGJ-DI for all filling volumes.

CONCLUSIONS

Given these observations, we recommend using a cut-off of 2 mm² /mmHg for clinical practice, values below can be considered abnormal. Given that 5.4% of the healthy subjects will have an EGJ-DI below 2 mm² /mmHg at 40 ml, we recommend using the 50 and 60 ml distention volumes. The clinical use of an upper limit for normality of EGJ-DI seems questionable.

Estimating Probability for Esophageal Obstruction: A Diagnostic Decision Support Tool Applying Machine Learning to Functional Lumen Imaging Probe Panometry

Background/Aims

This study aimed to develop a diagnostic tool using machine learning to apply functional luminal imaging probe (FLIP) panometry data to determine the probability of esophagogastric junction (EGJ) obstruction as determined using the Chicago Classification version 4.0 (CCv4.0) and high-resolution manometry (HRM).

Methods

Five hundred and fifty-seven adult patients that completed FLIP and HRM (with a conclusive CCv4.0 assessment of EGJ outflow) and 35 asymptomatic volunteers ("controls") were included. EGJ opening was evaluated with 16-cm FLIP performed during sedated endoscopy via EGJ-distensibility index and maximum EGJ diameter. HRM was classified according to the CCv4.0 as conclusive disorders of EGJ outflow or normal EGJ outflow (timed barium esophagram applied when required and available). The probability tool utilized Bayesian additive regression treesBART, which were evaluated using a leave-one-out approach and a holdout test set.

Results

Per HRM and CCv4.0, 243 patients had a conclusive disorder of EGJ outflow while 314 patients (and all 35 controls) had normal EGJ outflow. The model accuracy to predict EGJ obstruction (based on leave-one-out/holdout test set, respectively) was 89%/90%, with 87%/85% sensitivity, 92%/97% specificity, and an area under the receiver operating characteristic curve of 0.95/0.97. A free, open-source tool to calculate probability for EGJ obstruction using FLIP metrics is available at https://www.wklytics.com/nmgi/prob_flip.html.

Conclusions

Application of FLIP metrics utilizing a probabilistic approach incorporates the diagnostic confidence (or uncertainty) into the clinical interpretation of EGJ obstruction. This tool can provide clinical decision support during application of FLIP Panometry for evaluation of esophageal motility disorders.

Relationship between dysphagia, lower esophageal sphincter relaxation, and esophagogastric junction distensibility

BACKGROUND

It is debated whether high-resolution manometric (HRM) integrated relaxation pressure (IRP) or functional lumen imaging probe (FLIP) distensibility index (DI) is the superior measure of esophagogastric junction (EGJ) opening. We examined the relationship between the DI and IRP and assessed correlations with dysphagia symptoms in patients with achalasia and EGJ outflow obstruction (EGJOO).

METHODS

Patients with achalasia and those with barium tablet retention at the EGJ were grouped as follows: Group 1:Achalasia (IRP ≥ 15 mmHg + complete absence of normal peristalsis); Group 2: Manometric +FLIP EGJOO (IRP ≥ 15 mmHg with some intact peristalsis + DI ≤ 2.8 mm2 /mmHg); Group 3: Abnormal DI only (DI ≤ 2.8 mm2 /mmHg + IRP <15 mmHg); and Group 4: Normal IRP and DI (IRP ≥ 15 mmHg + DI > 2.8 mm2 /mmHg). Correlation between the DI, baseline lower esophageal sphincter pressure (BLESP), IRP, and dysphagia (Eckardt score) was assessed. Multivariable analysis was used to assess variables associated with dysphagia score ≥2.

KEY RESULTS

A total of 79 patients were included: Group 1 (n = 31), Group 2 (n = 33), Group 3 (n = 14), and Group 4 (n = 1). DI did not correlate with BLESP or IRP in the whole sample or subgroups. DI was the only variable associated with dysphagia score ≥2 (p = 0.006). DI < 1.25 mm2 /mmHg had sensitivity of 87% and specificity of 52% (p = 0.0003) for dysphagia score ≥2.

CONCLUSIONS & INFERENCES

DI does not correlate with HRM EGJ measurements and is the metric with the strongest effect on dysphagia severity. The various biological elements that may cause restrictive EGJ function should be the subject of future studies.

The Predictive Value of Intraoperative Esophageal Functional Luminal Imaging Probe Panometry in Patients With Achalasia Undergoing Peroral Endoscopic Myotomy: A Single-center Experience

Background/Aims

We evaluated the clinical significance and prognostic power of functional luminal imaging probe (FLIP) panometry in patients with achalasia treated with peroral endoscopic myotomy (POEM), and examined the clinical parameters associated with symptomatic improvement and the presence of contractility (POC) following POEM.

Methods

We reviewed the electronic medical records of patients with achalasia treated with FLIP panometry and POEM at a tertiary teaching hospital in Seoul, Republic of Korea. Follow-up examination was composed of esophageal manometry and questionnaires on symptoms. We analyzed the FLIP data by interpolating using the cubic spline method in MATLAB.

Results

We retrospectively analyzed 33 men and 35 women (mean age 52 ± 17 years), of whom 14, 39, and 15 patients were diagnosed with achalasia types I, II, and III, respectively. The FLIP panometry diagnoses were reduced esophagogastric junction opening (REO) with a retrograde contractile response (n = 43); REO with an absent contractile response (n = 5); REO with a normal contractile response (n = 11); and a retrograde contractile response (n = 9). Overall, the patients showed improvements in Eckardt scores following POEM from 6.48 ± 2.20 to 1.16 ± 1.15 (P < 0.01). Post-POEM symptomatic improvement was not significantly associated with any of the clinical parameters, including panometry diagnosis. Conversely, post-POEM POC was significantly associated with the presence of repetitive antegrade contractions and achalasia subtypes (both P < 0.01).

Conclusion

While FLIP panometry was not significantly associated with the clinical course of achalasia, FLIP panometry was associated with POC following POEM and may complement manometry in the functional evaluation of esophageal motility disorders.

Esophageal Achalasia: Diagnostic Evaluation

A precise diagnosis is key to the successful treatment of achalasia. Barium swallow, upper endoscopy and high-resolution manometry provide the necessary information about a patient's anatomy, absence of other diseases, and type of achalasia (I, II, III). High-resolution manometry also has prognostic value, the best results of treatment being obtained in type II achalasia according to the Chicago classification. Abdominal CT scanning and endoscopic ultrasound might be warranted if an underlying malignancy is suspected.

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.

Functional luminal imaging probe in the evaluation of esophago-gastric junction outflow obstruction

PURPOSE OF REVIEW

Esophagogastric junction outflow obstruction (EGJOO) comprises a heterogeneous group of conditions that demonstrate impaired deglutitive relaxation of the esophagogastric junction (EGJ) with intact esophageal peristalsis on high-resolution manometry. Functional luminal imaging probe (FLIP) panometry is a powerful tool that can help to clarify the etiology of this manometric diagnosis. The aim of this review is to summarize the use of FLIP for the evaluation and management of EGJOO.

RECENT FINDINGS

FLIP panometry provides measures of esophageal compliance at the EGJ and information on esophageal body contractile responses to balloon distention that have important implications for the management of patients with EGJOO. After excluding anatomic causes of impaired EGJ distensibility, FLIP panometry is useful in differentiating true lower esophageal sphincter dysfunction from manometric artifact. FLIP panometry has been shown to be useful in determining the need for invasive treatment in patients with EGJOO, and in intraoperative tailoring of myotomy procedures.

SUMMARY

FLIP panometry is easy to perform during endoscopy and provides useful information for characterizing the EGJOO population. FLIP panometry can be used to guide treatment and improve outcomes in the management of patients with EGJOO.

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.

Validation of Clinically Relevant Thresholds of Esophagogastric Junction Obstruction Using FLIP Panometry

BACKGROUND & AIMS

This study aimed to assess the accuracy of functional luminal imaging probe (FLIP) panometry to detect esophagogastric junction (EGJ) obstruction assigned by high-resolution manometry (HRM) and the Chicago Classification version 4.0 (CCv4.0).

METHODS

Six hundred eighty-seven adult patients who completed FLIP and HRM for primary esophageal motility evaluation and 35 asymptomatic volunteers (controls) were included. EGJ opening was evaluated with 16-cm FLIP during sedated endoscopy via EGJ-distensibility index (DI) and maximum EGJ diameter. HRM was classified according to CCv4.0 and focused on studies with a conclusive disorder of EGJ outflow (ie, achalasia subtypes I, II, or III; or EGJ outflow obstruction with abnormal timed barium esophagogram) or normal EGJ outflow.

RESULTS

All 35 controls had EGJ-DI >3.0 mm²/mmHg and maximum EGJ diameter >16 mm. Per HRM and CCv4.0, 245 patients had a conclusive disorder of EGJ outflow, and 314 patients had normal EGJ outflow. Among the 241 patients with reduced EGJ opening (EGJ-DI <2.0 mm²/mmHg and maximum EGJ diameter <12 mm) on FLIP panometry, 86% had a conclusive disorder of EGJ outflow per CCv4.0. Among the 203 patients with normal EGJ opening (EGJ-DI ≥2.0 mm²/mmHg and maximum EGJ diameter ≥16 mm) on FLIP panometry, 99% had normal EGJ outflow per CCv4.0.

CONCLUSIONS

FLIP panometry accurately identified clinically relevant conclusive EGJ obstruction as defined by CCv4.0 in patients evaluated for esophageal motor disorders. Thus, FLIP panometry is a valuable tool for both independent and complementary evaluation of esophageal motility.

Endoluminal Functional Lumen Imaging Probe Is Safe in Children Under Five Years Old

BACKGROUND

Endoluminal functional lumen imaging probe (EndoFLIP) is a minimally invasive, novel device that uses high-resolution impedance planimetry to measure important parameters of the gastrointestinal lumen that aid in the diagnosis of esophageal disorders. EndoFLiP is approved by the US Food and Drug Administration (FDA) for children 5 years and older. We sought to compare its safety and luminal characteristics between children under 5 years of age with children 5 years and older.

METHODS

A single-center retrospective review was performed to identify all patients < 21 years of age who underwent esophagogastroduodenoscopy (EGD) with EndoFLIP between October 2017 and November 2020. Results: Sixty-seven EGDs with EndoFLIP were performed in 56 patients, including 14 that were done in children < 5 years and 53 in children ≥5years. The median age in the < 5-year group was 1.7years (interquartile range [IQR], 0.9-4.4) and the youngest patient was 1 month old. The median age in ≥5-year group was 14.3 years (IQR, 8.2-16.2). Median procedure times were similar (32 minutes [IQR, 25-48] for the < 5-year group; 28 minutes [IQR, 20-33] for ≥5-year group; P  = 0.08). There were no adverse events or unplanned hospitalizations in either group. At 30 mL inflation, the pressure of the lower esophageal sphincter (LES) was statistically different between the 2 groups (P = 0.02).

CONCLUSION

EndoFLIP appears to be safe for use in our small cohort of children < 5 years of age and may be an important tool in the management of esophageal disorders in this age group. There was no difference in procedure time between our 2 age groups and there were no procedure-related complications.

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.

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.

Can FLIP guide therapy in idiopathic esophagogastric junction outflow obstruction?

BACKGROUND

Esophagogastric junction outflow obstruction (EGJOO) has a variable disease course. Currently, barium swallow (BaS) and manometric parameters are used to characterize clinically significant EGJOO. The esophagogastric junction distensibility index (EGJ-DI) measured via functional lumen imaging probe (FLIP) can provide complementary information. Our aim was to assess symptom response in patients with EGJOO and an abnormal EGJ-DI after botulinum toxin (BT) treatment.

METHODS

A prospective cohort study of adults with idiopathic EGJOO was performed from September 2019 to March 2021. Patients with dysphagia underwent upper endoscopy with FLIP. If the EGJ-DI was abnormally low, BT was injected. Data examined included demographics, medical history, endoscopic and FLIP findings, BaS, manometry, and Eckardt score (ES). ES improvement was assessed via paired samples t-test. Pearson's chi-square tests were used to assess for associations.

RESULTS

Of the 20 patients, 75% had an abnormal EGJ-DI and underwent BT injections. Mean ES for patients with abnormal EGJ-DIs significantly improved from baseline to 1, 3, and 6 month follow-up (P-values: 0.01, 0.05, and 0.02, respectively). There was a significant association between an abnormal EGJ-DI with delayed bolus transit and presence of rapid drink challenge panesophageal pressurization on manometry: P = 0.03 and P = 0.03.

CONCLUSION

This prospective study revealed that an abnormal EGJ-DI can guide BT as assessed via symptomatic response. Additionally, abnormal EGJ-DI measurements were significantly associated with other parameters used previously to determine clinically relevant EGJOO. Larger follow-up studies are warranted to further elucidate guidance for therapy in EGJOO.

Use of the functional luminal imaging probe in pediatrics: A comparison study of patients with achalasia before and after endoscopic dilation and non-achalasia controls

BACKGROUND

Achalasia is an esophageal motility disorder characterized by esophagogastric junction (EGJ) dysfunction and impaired esophageal peristalsis with significant impact on quality of life. While the functional luminal imaging probe (FLIP) has been used to assess EGJ distensibility in achalasia, its clinical utility in pediatrics is limited due to absence of normative values and correlations with clinical outcomes in children. Thus, we sought to evaluate FLIP's use in a pediatric achalasia cohort undergoing dilations and non-achalasia controls.

METHODS

We conducted a retrospective study of pediatric patients with achalasia who underwent FLIP before and immediately after balloon dilations and compared to a non-achalasia cohort.

KEY RESULTS

Thirty patients with achalasia (mean age, 15.2 years; 40% female), including fourteen treatment-naïve and thirteen controls (mean age, 7.9 years; 61% female) were identified. Median EGJ distensibility index (EGJ-DI) 2.07 mm²  mmHg^-1 and diameter (9.23 mm) in treatment-naïve patients were significantly lower compared to controls (EGJ-DI 6.8 mm²  mmHg^-1 ; diameter 18.61 mm; (p < 0.001). Balloon dilations resulted in a significant increase in EGJ-DI immediately after the dilation, particularly in treatment-naïve patients (p < 0.001), and a significant improvement in Eckardt scores (p < 0.001).

CONCLUSIONS & INFERENCES

Functional luminal imaging probe measurements of EGJ-DI in pediatric patients with achalasia are mostly consistent with adult findings. However, normal EGJ-DI is seen in symptomatic patients, including treatment-naive, highlighting the need for pediatric reference data. Balloon dilations achieve a significant increase in EGJ-DI with improvement in Eckardt scores, confirming the therapeutic value of dilations in achalasia management.

Clinical usefulness of esophageal high resolution manometry and adjunctive tests: An update

High resolution manometry (HRM), developed from conventional manometry, is the gold standard for assessment of esophageal motor function worldwide. The Chicago Classification, now in its fourth iteration, is the modern standard for HRM categorization of esophageal motility disorders. The HRM protocol has expanded from the original 10 supine swallow standard, to include upright swallows, and provocative maneuvers such as multiple rapid swallows, rapid drink challenge and standardized test meal. Impedance has been incorporated into HRM for visualization of bolus clearance. Futhermore, barium radiography and functional lumen imaging probe complement HRM when evidence of esophagogastric junction obstruction is inconclusive. The biggest impact of HRM is in the improved diagnosis and subtyping of achalasia spectrum disorders, with implications on management. Spastic disorders and absent contractility are better characterized. Within the reflux spectrum, HRM provides definition of morphology and tone of the esophagogastric junction, and assesses integrity of esophageal body peristalsis, which have pathophysiologic implications for reflux and its clearance. HRM provides characterization of behavioral disorders such as supragastric belching and rumination syndrome, which can mimic reflux disease. Thus, HRM has revolutionized the evaluation of esophageal motor function, and has expanded the utility of esophageal manometry in clinical practice.

Evaluating esophageal motility beyond primary peristalsis: Assessing esophagogastric junction opening mechanics and secondary peristalsis in patients with normal manometry

BACKGROUND

Functional luminal imaging probe (FLIP) Panometry assesses the esophageal response to distention and may complement the assessment of primary peristalsis on high-resolution manometry (HRM). We aimed to investigate whether FLIP Panometry provides complementary information in patients with normal esophageal motility on HRM.

METHODS

Adult patients that completed FLIP and had an HRM classification of normal motility were retrospectively identified for inclusion. 16-cm FLIP studies performed during endoscopy were evaluated to assess EGJ distensibility, secondary peristalsis, and identify an abnormal response to distention involving sustained LES contraction (sLESC). Clinical characteristics and esophagram were assessed when available.

KEY RESULTS

Of 164 patients included (mean(SD) age 48(16) years, 75% female), 111 (68%) had normal Panometry with EGJ-distensibility index (DI) ≥2.0 mm2 /mmHg, maximum EGJ diameter ≥16mm and antegrade contractions. Abnormal EGJ distensibility was observed in 44/164 (27%), and 38/164 (23%) had an abnormal contractile response to distension. sLESC was observed in 11/164 (7%). Among 68 patients that completed esophagram, abnormal EGJ distensibility was more frequently observed with an abnormal esophagram than normal EGJ opening: 14/23 (61%) vs 10/45 (22%); P=0.003. Epiphrenic diverticula were present in 3/164 patients: 2/3 had sLESC.

CONCLUSIONS & INFERENCES

Symptomatic patients with normal esophageal motility on HRM predominantly have normal FLIP Panometry; however, abnormal FLIP findings can be observed. While abnormal Panometry findings appear clinically relevant via an association with abnormal bolus retention, complementary tests, such as provocative maneuvers with HRM and timed barium esophagram, are useful to determine clinical context.

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.

Pyloric distensibility in health and disease

Until recently, gastric motility measurements in humans were mostly limited to accommodation (using barostat or 3-dimensional imaging studies of gastric volume) and gastric emptying tests, the latter being the only one performed in routine clinical care. Accurate and easy to use techniques were lacking to assess pyloric function in health and disease. Recently, pyloric distensibility has been developed and validated to assess pyloric opening. Several studies confirmed that pyloric distensibility was decreased in gastroparesis and correlated with gastric emptying as well as gastroparesis symptoms. In addition, pyloric distensibility may predict outcome of endoscopic techniques targeting the pylorus, namely intrapyloric botulinum toxin injection and gastric per-oral pyloromyotomy. Pyloric distensibility appears therefore to be a promising and useful new tool in the workup of gastroparesis patients.

European guidelines on achalasia: United European Gastroenterology and European Society of Neurogastroenterology and Motility recommendations

INTRODUCTION

Achalasia is a primary motor disorder of the oesophagus characterised by absence of peristalsis and insufficient lower oesophageal sphincter relaxation. With new advances and developments in achalasia management, there is an increasing demand for comprehensive evidence-based guidelines to assist clinicians in achalasia patient care.

METHODS

Guidelines were established by a working group of representatives from United European Gastroenterology, European Society of Neurogastroenterology and Motility, European Society of Gastrointestinal and Abdominal Radiology and the European Association of Endoscopic Surgery in accordance with the Appraisal of Guidelines for Research and Evaluation II instrument. A systematic review of the literature was performed, and the certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation methodology. Recommendations were voted upon using a nominal group technique.

RESULTS

These guidelines focus on the definition of achalasia, treatment aims, diagnostic tests, medical, endoscopic and surgical therapy, management of treatment failure, follow-up and oesophageal cancer risk.

CONCLUSION

These multidisciplinary guidelines provide a comprehensive evidence-based framework with recommendations on the diagnosis, treatment and follow-up of adult achalasia patients.

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.

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.

Estimation of mechanical work done to open the esophagogastric junction using functional lumen imaging probe panometry

In this study, we quantify the work done by the esophagus to open the esophagogastric junction (EGJ) and create a passage for bolus flow into the stomach. Work done on the EGJ was computed using functional lumen imaging probe (FLIP) panometry. Eighty-five individuals underwent FLIP panometry with a 16-cm catheter during sedated endoscopy including asymptomatic controls (n = 14), 45 patients with achalasia (n = 15 each, three subtypes), those with gastroesophageal reflux disease (GERD; n = 13), those with eosinophilic esophagitis (EoE; n = 8), and those with systemic sclerosis (SSc; n = 5). Luminal cross-sectional area (CSA) and pressure were measured by the FLIP catheter positioned across the EGJ. Work done on the EGJ (EGJW) was computed (millijoules, mJ) at 40-mL distension. Additionally, a separate method was developed to estimate the "work required" to fully open the EGJ (EGJROW) when it did not open during the procedure. EGJW for controls had a median [interquartile range (IQR)] value of 75 (56-141) mJ. All achalasia subtypes showed low EGJW compared with controls (P < 0.001). Subjects with GERD and EoE had EGJW 54.1 (6.9-96.3) and 65.9 (10.8-102.3) mJ, similar to controls (P < 0.08 and P < 0.4, respectively). The scleroderma group showed low values of EGJW, 12 mJ (P < 0.001). For patients with achalasia, EGJROW was the greatest and had a value of 210.4 (115.2-375.4) mJ. Disease groups with minimal or absent EGJ opening showed low values of EGJW. For patients with achalasia, EGJROW significantly exceeded EGJW values of all other groups, highlighting its unique pathophysiology. Balancing the relationship between EGJW and EGJROW is potentially useful for calibrating achalasia treatments and evaluating treatment response.NEW & NOTEWORTHY Changes in pressure and diameter occur at the EGJ during esophageal emptying. Similar changes can be observed during FLIP panometry. Data from healthy and diseased individuals were used to estimate the mechanical work done on the EGJ during distension-induced relaxation or, in instances of failed opening, work required to open the EGJ. Quantifying these parameters is potentially valuable to calibrate treatments and gauge treatment efficacy for subjects with disorders of EGJ function, especially achalasia.

Esophagogastric Junction Opening Parameters Are Consistently Abnormal in Untreated Achalasia

Achalasia is a disorder of impaired lower esophageal sphincter (LES) relaxation and failed peristalsis traditionally characterized by manometry.¹ As impaired LES relaxation is a mechanism of reduced esophagogastric junction (EGJ) opening, abnormally reduced EGJ distensibility assessed with functional luminal imaging probe (FLIP) was reported among patients with untreated achalasia.^2-5 Therefore, we aimed to describe the performance characteristics of EGJ opening parameters on FLIP panometry among a large cohort of treatment-naïve achalasia patients.

Solid Swallow Examination During High Resolution Manometry and EGJ-Distensibility Help Identify Esophageal Outflow Obstruction in Non-obstructive Dysphagia

Single water swallow (SWS) high-resolution manometry (HRM) may miss relevant esophageal motility disorders. Solid test meal (STM) during HRM and lately the functional lumen imaging probe (FLIP) have been shown to be of diagnostic value in the assessment of motility disorders. We aimed to assess the diagnostic yield of STM and FLIP in non-obstructive dysphagia (NOD). Patients assessed for dysphagia with both HRM and FLIP between April 2016 and August 2019 were analyzed for signs of non-obstructive EGJ outflow obstruction (EGJOO) according to Chicago Classification 3.0 (CCv3) and CC adapted for the use with solid swallows (CC-S), followed by an individual group-specific analysis. Five subjects without dysphagia served as control group. Standard HRM- and FLIP-values as well as esophagograms and Eckardt Scores were analyzed. Forty-two patients were identified (male/female, 14/36, median age 62). Twenty-five (59.5%) were diagnosed with EGJOO during STM only (= SWS-negative patients; CC-S). The EGJ distensibility index (EGJ-DI) of symptomatic patients was significantly lower compared to the control group (p = 0.006). EGJ-DI was < 3mm²/mmHg in 67% and 88% of patients diagnosed according to CC-S and CCv3, respectively. The IRP during STM showed a significant association to the corresponding EGJ-DI values (p < 0.001). Seventy-six percent of patients received treatment because of additional STM evaluation with a favorable clinical response rate of 89%. STM and FLIP identify EGJOO in symptomatic patients with normal SWS during HRM. STM resembles an inexpensive and clinically meaningful option to diagnose motility disorders and helps to select patients for interventional treatment.