High resolution manometry: the Ray Clouse legacy

Anorectal Manometry in Pediatric Colorectal Surgical Care

BACKGROUND

Pediatric colorectal specialists care for patients with a variety of defecation disorders. Anorectal (AR) manometry testing is a valuable tool in the diagnosis and management of these children. This paper provides a summary of AR manometry techniques and applications as well as a review of AR manometry findings in pediatric patients with severe defecation disorders referred to a pediatric colorectal center. This is the first study describing multi-year experience using a portable AR manometry device in pediatric patients.

METHODS

An electronic medical record review was performed (1/2018 to 12/2023) of pediatric patients with defecation disorders who had AR manometry testing. Demographics, diagnostic findings, and outcomes are described.

KEY RESULTS

A total of 297 unique patients (56.9% male, n = 169) had AR manometry testing. Of these, 72% (n = 188) had dyssynergic defecation patterns, of which 67.6% (n = 127) had fecal soiling prior to treatment. Pelvic rehabilitation (PR) was administered to 35.4% (n = 105) of all patients. A total of 79.5% (n = 58) of the 73 patients that had fecal soiling at initial presentation and completed PR with physical therapy and a bowel management program were continent after therapy. AR manometry was well tolerated, with no major complications.

CONCLUSIONS

AR manometry is a simple test that can help guide the management of pediatric colorectal surgical patients with defecation disorders. As a secondary finding, PR is a useful treatment for patients with dyssynergic stooling.

Esophageal high-resolution manometry demands visual interpretation in addition to mathematical software-based analysis

PURPOSE

Esophageal high-resolution manometry (HRM) revolutionized esophageal function testing due to the intuitive colorful and agreeable-to-the-eyes plots (Clouse plots). HRM execution and interpretation is guided by the Chicago Classification. The well-established metrics for interpretation allows a reliable automatic software analysis. Analysis based on these mathematical parameters, however, ignores the valuable visual interpretation unique to human eyes and based on expertise.

METHODS

We compiled some situations where visual interpretation added useful information for HRM interpretation.

RESULTS

Visual interpretation may be useful in cases of hypomotility, premature waves, artifacts, segmental abnormalities of peristalsis, and extra-luminal non-contractile findings.

CONCLUSION

These extra findings can be reported apart from the conventional parameters.

A Short History of High-Resolution Esophageal Manometry

High-resolution esophageal manometry (HRM) utilizes sufficient pressure sensors such that intraluminal pressure is monitored as a continuum along luminal length, similar to time viewed as a continuum on polygraph tracings in 'conventional' manometry. When HRM is coupled with pressure topography plotting, and pressure amplitude is transformed into spectral colors with isobaric areas indicated by same-colored regions, "Clouse plots" are generated. HRM has several advantages compared to the technology that it replaced: (1) the contractility of the entire esophagus can be viewed simultaneously in a uniform standardized format, (2) standardized objective metrics of peristaltic and sphincter function can be systematically applied for interpretation, and (3) topographic patterns of contractility are more easily recognized with greater reproducibility. Leveraging these advantages led to the current standard for the interpretation of clinical esophageal HRM studies, the Chicago Classification (CC), now in its fourth iteration. Compared to conventional manometry, HRM has vastly improved the sensitivity for detecting achalasia, largely due to the objectivity and accuracy of identification of impaired esophagogastric junction (EGJ) relaxation. Additionally, it has led to the subcategorization of achalasia into three clinically relevant subtypes, differentiated by the contractile function of the esophageal body, and identified an additional disorder of EGJ outflow obstruction wherein esophageal peristalsis is preserved. Headway has also been made in understanding hypocontractile and hypercontractile conditions. In summary, HRM and the CC process have revolutionized our understanding of esophageal motility and motility disorders. Moving forward, there will always be remaining challenges, but we now have the tools to meet them.

High-Resolution Manometry Thresholds and Motor Patterns Among Asymptomatic Individuals

OBJECTIVE

High-resolution manometry (HRM) is the current standard for characterization of esophageal body and esophagogastric junction (EGJ) function. We aimed to examine the prevalence of abnormal esophageal motor patterns in health, and to determine optimal thresholds for software metrics across HRM systems.

DESIGN

Manometry studies from asymptomatic adults were solicited from motility centers worldwide, and were manually analyzed using integrated relaxation pressure (IRP), distal latency (DL), and distal contractile integral (DCI) in standardized fashion. Normative thresholds were assessed using fifth and/or 95th percentile values. Chicago Classification v3.0 criteria were applied to determine motor patterns across HRM systems, study positions (upright vs supine), ages, and genders.

RESULTS

Of 469 unique HRM studies (median age 28.0, range 18-79 years). 74.6% had a normal HRM pattern; none had achalasia. Ineffective esophageal motility (IEM) was the most frequent motor pattern identified (15.1% overall), followed by EGJ outflow obstruction (5.3%). Proportions with IEM were lower using stringent criteria (10.0%), especially in supine studies (7.1%-8.5%). Other motor patterns were rare (0.2%-4.1% overall) and did not vary by age or gender. DL thresholds were close to current norms across HRM systems, while IRP thresholds varied by HRM system and study position. Both fifth and 95th percentile DCI values were lower than current thresholds, both in upright and supine positions.

CONCLUSIONS

Motor abnormalities are infrequent in healthy individuals and consist mainly of IEM, proportions of which are lower when using stringent criteria in the supine position. Thresholds for HRM metrics vary by HRM system and study position.

Making Sense of Nonachalasia Esophageal Motor Disorders

Achalasia is the prototypical obstructive motor disorder diagnosed using HRM, but non-achalasia motor disorders are often identified in symptomatic patients. The clinical relevance of these disorders are assessed using ancillary HRM maneuvers (multiple rapid swallows, rapid drink challenge, solid swallows) that augment the standard supine HRM evaluation by challenging peristaltic function. Finding obstructive motor physiology in non-achalasia motor disorders may raise the option of invasive management akin to achalasia. Certain non-achalasia disorders, particularly hypermotility disorders, may manifest as epiphenomena seen with esophageal hypersensitivity. Symptomatic management is offered for superimposed reflux disease, psychological disorders, functional esophageal disorders, and behavioral disorders.

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.

Evaluation of the Esophagogastric Junction on High Resolution Manometry

The esophagogastric junction (EGJ) is a complex barrier between the thoracic and abdominal luminal gut compartments, comprised primarily of the lower esophageal sphincter (LES) and crural diaphragm. Although closed at rest, the EGJ relaxes to allow antegrade bolus transit and retrograde venting of air. Abnormal relaxation is the hallmark of achalasia spectrum disorders, while increased frequency of transient lower esophageal sphincter relaxations and/or EGJ disruption are seen in gastroesophageal reflux disease. High resolution manometry (HRM) is the modern day gold standard for assessment of EGJ morphology and function, with better performance characteristics compared with endoscopy and barium esophagography. Conventional LES metrics defining EGJ function include resting LES pressure as well as postswallow residual pressures. Newer HRM-based metrics include EGJ contractile integral, which measures static barrier function at rest, and EGJ morphology, which characterizes the relationship between LES and crural diaphragm. Provocative maneuvers assess dynamic EGJ function during physiological or pharmacologic stress. The most useful of these maneuvers, the rapid drink challenge, assesses for latent obstruction, while multiple rapid swallows evaluate adequacy of deglutitive inhibition. Amyl nitrate and cholecystokinin administration can segregate motor from structural obstruction. Newer provocative tests (straight leg raise maneuver, abdominal compression) and novel diagnostic tools (functional lumen imaging probe) complement HRM evaluation of the EGJ. Although current HRM metrics and maneuvers show promise in identifying clinically relevant EGJ abnormalities, future investigations evaluating management outcomes will improve segregation of normal from abnormal EGJ morphology and function.

The Clinical Utility of Provocative Maneuvers at Esophageal High-resolution Manometry (HRM)

Esophageal high-resolution manometry (HRM) assesses esophageal motor function and is indicated both for evaluation of esophageal symptoms and before antireflux interventions. HRM studies are interpreted and esophageal motor diagnoses made according to the Chicago Classification, version 3.0 algorithm, which is based on ten 5 mL supine water swallows. However, this practice of single liquid swallows performed in the supine position does not reflect typical "real-life" swallowing, and may not reproduce the patient's presenting symptoms. Therefore, provocative maneuvers at HRM-beyond these 10 standard swallows-can afford additional insights into esophageal motor function with clinically significant implications, and represent areas of exciting investigation and innovation. Accordingly, the 2020 American College of Gastroenterology Guidelines on Esophageal Physiologic Testing conditionally recommend their inclusion in the HRM protocol. In this clinical review, we discuss the supporting data for and clinical utility of provocative maneuvers at HRM that include changes in body position or accessories (upright swallows, "bridge" position, straight leg raise, abdominal compression), bolus consistency (solid swallows, test meals, postprandial high-resolution impedance manometry), bolus frequency (multiple rapid swallows), the volume of bolus (rapid drink challenge/multiple water swallows), and the use of pharmacological agents.

VALIDATION OF A NEW WATER-PERFUSED HIGH-RESOLUTION MANOMETRY SYSTEM

Background:

High-resolution manometry is more costly but clinically superior to conventional manometry. Water-perfused systems may decrease costs, but it is unclear if they are as reliable as solid-state systems, and reference values are interchangeable.

Aim:

To validate normal values for a new water-perfusion high-resolution manometry system.

Methods:

Normative values for a 24-sensors water perfused high-resolution manometry system were validated by studying 225 individuals who underwent high resolution manometry for clinical complaints. Patients were divided in four groups: group 1 - gastroesophageal reflux disease; group 2 - achalasia; group 3 - systemic diseases with possible esophageal manifestation; and group 4 - dysphagia.

Results:

In group 1, a hypotonic lower esophageal sphincter was found in 49% of individuals with positive 24 h pH monitoring, and in 28% in pH-negative individuals. In groups 2 and 3, aperistalsis was found in all individuals. In group 4, only one patient (14%) had normal high-resolution manometry.

Conclusions:

The normal values determined for this low-cost water-perfused HRM system with unique peristaltic pump and helicoidal sensor distribution are discriminatory of most abnormalities of esophageal motility seen in clinical practice.

What is new in Chicago Classification version 4.0?

Since publication of Chicago Classification version 3.0 in 2015, the clinical and research applications of high-resolution manometry (HRM) have expanded. In order to update the Chicago Classification, an International HRM Working Group consisting of 52 diverse experts worked for two years and utilized formally validated methodologies. Compared with the prior iteration, there are four key modifications in Chicago Classification version 4.0 (CCv4.0). First, further manometric and non-manometric evaluation is required to arrive at a conclusive, actionable diagnosis of esophagogastric junction (EGJ) outflow obstruction (EGJOO). Second, EGJOO, distal esophageal spasm, and hypercontractile esophagus are three manometric patterns that must be accompanied by obstructive esophageal symptoms of dysphagia and/or non-cardiac chest pain to be considered clinically relevant. Third, the standardized manometric protocol should ideally include supine and upright positions as well as additional manometric maneuvers such as the multiple rapid swallows and rapid drink challenge. Solid test swallows, postprandial testing, and pharmacologic provocation can also be considered for particular conditions. Finally, the definition of ineffective esophageal motility is more stringent and now encompasses fragmented peristalsis. Hence, CCv4.0 no longer distinguishes between major versus minor motility disorders but simply separates disorders of EGJ outflow from disorders of peristalsis.

Enhancing High-Resolution Esophageal Manometry: Use of Ancillary Techniques and Maneuvers

High-resolution manometry evaluates esophageal motor function using 10 supine water swallows. Superimposing impedance over high-resolution manometry pressure topography assesses the relationship between contraction and bolus propulsion and identifies inadequate clearance. Ancillary techniques and maneuvers augment the standard supine high-resolution manometry evaluation by challenging peristaltic function. Increasing bolus volume (rapid drink challenge) and altering bolus consistency (standardized test meal, solid swallows) enhance identification of esophageal outflow obstruction syndromes. Physiologic maneuvers (multiple rapid swallows, abdominal compression) address the ability of the esophageal smooth muscle to augment contraction vigor. Pharmacologic challenge is less commonly used clinically, and elucidates pathophysiology of esophageal motor disorders.

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 Emerging Importance of High-Resolution Manometry in the Evaluation and Treatment of Deglutition in Infants, Children, and Adults: New Opportunities for Speech-Language Pathologists

Purpose Diagnostic precision and prolonged testing before, during, and after deglutition is lacking across the age spectrum. Conventional clinical evaluation and radiologic methods are widely used but are reliant on human perception, carrying the risk of subjectivity. High-resolution manometry (HRM) is an emerging clinical and research tool and has the capability to objectively measure the dynamics, kinetics, regulatory, and correlation aspects of deglutition. Method We review the basics of manometry and the methods, metrics, and applications of this technology across the age spectrum. The goal is to aid in the translation of HRM from research tool to clinical use by the speech-language pathologist in the development of better global plans to understand normal and abnormal deglutition. Results HRM is an easily adaptable precise diagnostic tool that can be used to examine deglutition phases and abnormalities across the age spectrum from neonates to nonagenarians and can be a valuable adjunct to specialty evaluation of persistent deglutition disorders. Conclusion New opportunities will emerge upon further research for larger-scale translation once normative data and recognition of biomarkers of abnormality are ascertained.

Trans-esophagogastric junction pressure gradients during straight leg raise maneuver on high-resolution manometry associate with large hiatus hernias

BACKGROUND

Straight leg raise (SLR) while supine increases intra-abdominal pressure. We hypothesized that elevations in intra-abdominal pressure would transmit into the thoracic cavity if the esophagogastric junction (EGJ) was disrupted.

METHODS

Consecutive patients undergoing esophageal HRM were included if they had adequate SLR (hip flexion with knees extended for ≥ 5 seconds while supine). EGJ morphology was subtyped based on lower esophageal sphincter (LES) and crural diaphragm (CD) location (type 1: LES and CD overlap; type 2: separation of < 3 cm; type 3: separation of ≥ 3 cm). EGJ tone was assessed using EGJ contractile integral (EGJ-CI). HRM studies were analyzed according to Chicago Classification v3.0. Mean and peak intra-thoracic and abdominal pressures were measured at baseline and during SLR using on-screen software tools. Trans-EGJ gradients were compared, and pressure gradient < 1 mmHg denoted the equalization of pressures.

KEY RESULTS

Of 430 patients, 248 (57.5 ± 0.9 years, 69.4% F) completed SLR. EGJ morphology was type 1 in 122 (49.2%), type 2 in 56 (22.6%) and type 3 in 40 (16.1%). In types 1 and 2 EGJ, neither the mean nor peak trans-EGJ pressure gradient changed with SLR (P ≥ .17 for each). In contrast, in type 3 EGJ, peak pressure gradient decreased significantly following SLR (3.5 ± 1.8 mmHg vs. -8.6 ± 4.8 mmHg, P = .01). More type 3 EGJ patients equalized peak (65%) pressures across EGJ compared with types 1 and 2 (27%, P < .001).

CONCLUSIONS AND INFERENCES

The evaluation of intra-abdominal and intra-thoracic pressures with SLR during esophageal HRM can provide evidence of physiological disruption of the EGJ barrier.

Higher Esophageal Symptom Burden in Obese Subjects Results From Increased Esophageal Acid Exposure and Not From Dysmotility

BACKGROUND & AIMS

Esophageal motor disorders (EMD) and pathologic reflux are often identified in obese individuals, but it is not clear how obesity contributes to these symptoms. We examined the relationships among symptom burden, EMD, acid exposure time (AET), symptom association probability, and body mass index (BMI).

METHODS

We performed a retrospective study of 1089 consecutive patients who underwent high-resolution manometry, of which 426 patients also underwent reflux monitoring off acid suppression, over a 2-year period at a tertiary referral center. Symptom burden was assessed by questionnaires to determine dominant symptom intensity (DSI; product of symptom severity, and frequency, on 5-point Likert scales) and global symptom severity (GSS; global esophageal symptoms on 10-cm visual analog scales) at the time of esophageal testing; BMIs were recorded. We compared proportions of patients with EMD and abnormal reflux burden among BMI categories and correlated them with symptom burden.

RESULTS

Four-hundred thirty-three patients (39.8%) met the criteria for EMD. Esophageal outflow obstruction was observed in higher proportions of patients with low BMIs (underweight, 25.9%; normal, 14.1%; overweight, 13.9%; and obese, 9.8%; P = .037), but EMDs were less frequent in obese patients (P = .047), despite higher symptom burden compared with non-obese patients (DSI, 10.5 ± 0.3 vs 9.7 ± 0.2; P = .03 and GSS, 6.5 ± 1 vs 5.9 ± 1; P = .01). Among the 426 patients who underwent reflux monitoring, the proportions with total AET (P = .02), and upright AET (P < .001) increased among BMI categories, supine AET trended strongly (P = .06), in combination with increasing DSI and GSS (P ≤ .001 for each comparison). BMI correlated with symptom burden, higher AET, and positive symptom association probability (P < .01 for each analysis).

CONCLUSIONS

Increased symptom burden in obese individuals correlates with esophageal acid burden but not with motor disorders.

Mosapride Improves Lower Esophageal Sphincter and Esophageal Body Function in Patients With Minor Disorders of Esophageal Peristalsis

Background/Aims

High-resolution manometry (HRM) has broadened the awareness of minor esophageal peristaltic disorders. However, the treatments for these minor disorders are limited and the role of prokinetics has been controversial. This study evaluates the effect of mosapride in patients with minor peristaltic disorders.

Methods

This study prospectively enrolled 21 patients with esophageal symptoms who were diagnosed with minor peristaltic disorders by gastroscopy and HRM using the Chicago classification version 3.0. Patients received mosapride 30 mg daily for 2 weeks. Symptoms were assessed using the abbreviated World Health Organization quality of life scale (WHOQOL-BREF) and a HRM study was performed before and after 2 weeks of treatment.

Results

HRM metrics of lower esophageal sphincter (LES) respiratory mean pressure (median 14.6 mmHg vs 17.3 mmHg; interquartile range [IQR] 8.7-22.5 mmHg vs 12.5-25.9 mmHg; P = 0.004) and distal contractile integral (median 343.8 mmHg·sec·cm vs 698.1 mmHg·sec·cm; IQR 286.5-795.9 mmHg·sec·cm vs 361.0-1127.6 mmHg·sec·cm; P = 0.048) were significantly increased after treatment. Complete response (≥ 80.0%), satisfactory response (≥ 50.0%), partial response (< 50.0%), and refractory response rates were 19.0%, 52.4%, 14.3%, and 14.3%, respectively. However, there was no statistical difference in all WHOQOL-BREF scores before and after treatment. Univariate analysis showed LES respiratory mean pressure (P = 0.036) was associated with symptom improvement (complete + satisfactory group). However, no statistical difference was found in other factors after multivariate analysis.

Conclusions

Mosapride improved esophageal symptoms and significantly increased LES respiratory mean pressure and distal contractile integral. Therefore, mosapride could enhance LES and esophageal body contraction pressures in patients with minor peristaltic disorders.

Esophageal Motility after Extensive Circumferential Endoscopic Submucosal Dissection for Superficial Esophageal Cancer

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD) for superficial esophageal cancer is sometimes extensive, and in our experience, patients not infrequently present with dysphagia after ESD even in the absence of esophageal stricture. The aim of this study was to evaluate esophageal motility using high-resolution manometry (HRM) in patients with and without dysphagia after extensive circumferential ESD.

METHODS

HRM was performed in a total of 52 patients who had undergone ESD for superficial esophageal cancer and a mucosal defect after ESD exceeded more than two-thirds of the esophageal circumference. The frequency and type of esophageal dysmotility and the relationship between esophageal motility and dysphagia were evaluated.

RESULTS

Esophageal dysmotility was observed in 13 patients (25%): jackhammer esophagus in 4, esophagogastric junction outflow obstruction in 4, absent contractility in 2, and distal esophageal spasm, ineffective esophageal motility, and fragmented peristalsis in 1 patient each. Of the 22 patients with dysphagia after ESD, 9 (41%) had esophageal dysmotility. Of the 30 patients without dysphagia after ESD, 4 (13%) had esophageal dysmotility. The relationship between dysmotility and dysphagia was significant (p = 0.025).

CONCLUSIONS

Esophageal dysmotility exists in approximately one-quarter of patients after extensive circumferential ESD, which is associated with dysphagia in the absence of esophageal stricture.

Esophageal motility disorders: new perspectives from high-resolution manometry and histopathology

High-resolution manometry (HRM) and peroral endoscopic myotomy (POEM) have contributed significantly to the field of esophageal motility disorders in recent years. The development of HRM has categorized various esophageal motility disorders with a focus on a diverse range of manometric anomalies. Additionally, the Chicago classification criteria is widely used for manometric diagnosis. Moreover, POEM was introduced as a minimally invasive radical therapy for achalasia and shows promise for other spastic esophageal motility disorders as well. POEM has also enabled a transluminal endoscopic approach for determining the histology of the esophageal muscle layer, which is expected to assist in elucidating the etiology of disorders associated with esophageal motility. The purpose of this review is to update the diagnosis, pathology, and treatment of esophageal motility disorders, with a focus on the recent advances in this field.

Gastroesophageal flap valve reflected EGJ morphology and correlated to acid reflux

OBJECTIVE

The anatomy of esophagogastric junction (EGJ) serves as the anti-reflux barrier. The gastroesophageal flap valve (GEFV) is a component of EGJ. The aim of the current study was to assess its correlation with the esophageal acid exposure and the impact on anti-reflux barrier function by using the metrics of EGJ contraction.

METHODS

Eighty three patients with typical GERD symptoms were included in the study. Upper endoscopy, high-resolution manometry (HRM) and 24 h multichannel intraluminal impedance-pH (MII-pH) monitoring were performed in all patients. GEFV was determined as four grades during endoscopic examination based on the Hill classification. The esophageal pressure topography (EPT) metrics defined in the updated Chicago Classification were measured by HRM, including integrated relaxation pressure (IRP), EGJ contractile index (EGJ-CI),expiratory EGJ pressure(EGJP-exp) and inspiratory EGJ pressure (EGJP-insp).

RESULTS

The GEFV grade III and IV was more commonly found in patients with esophagitits (p < 0.05). The acid exposure time (AET%) and supine AET% were lower in patients with GEFV grade I (p < 0.01). There was weak correlation between AET% and GEFV grades (r = 0.27, p = 0.013). There were more EGJ morphology type III in patients with GEFV grade IV (p < 0.05).There were no significant differences on the values of four HRM metrics among the patients with different GEFV grades (p > 0.05).

CONCLUSION

The GEFV grades were associated with acid reflux positively and could be a good reflection of EGJ morphology in HRM. But it had no impact on the four HRM metrics. Our research revealed that GEFV may play an assistant role in the anti-reflux barrier.

Expert consensus document: Advances in the management of oesophageal motility disorders in the era of high-resolution manometry: a focus on achalasia syndromes

High-resolution manometry (HRM) and new analysis algorithms, summarized in the Chicago Classification, have led to a restructured classification of oesophageal motility disorders. This advance has led to increased detection of clinically relevant disorders, in particular achalasia. It has become apparent that the cardinal feature of achalasia - impaired lower oesophageal sphincter (LES) relaxation - can occur in several disease phenotypes: without peristalsis (type I), with pan-oesophageal pressurization (type II), with premature (spastic) distal oesophageal contractions (type III), or with preserved peristalsis (outlet obstruction). Furthermore, no manometric pattern is perfectly sensitive or specific for achalasia caused by a myenteric plexopathy, and there is no biomarker for this pathology. Consequently, physiological testing reveals other syndromes not meeting achalasia criteria that also benefit from therapies formerly reserved for achalasia. These findings have become particularly relevant with the development of a minimally invasive technique for performing a long oesophageal myotomy, the per-oral endoscopic myotomy (POEM). Optimal management is to render treatment in a phenotype-specific manner; that is, POEM calibrated to patient-specific physiology for spastic achalasia and the spastic disorders, and more conservative strategies such as pneumatic dilation for the disorders limited to the LES. This Consensus Statement examines the effect of HRM on our understanding of oesophageal motility disorders, with a focus on the diagnosis, epidemiology and management of achalasia and achalasia-like syndromes.

Clinical Practice Update: The Use of Per-Oral Endoscopic Myotomy in Achalasia: Expert Review and Best Practice Advice From the AGA Institute

The purpose of this review is to describe a place for per-oral endoscopic myotomy (POEM) among the currently available robust treatments for achalasia. The recommendations outlined in this review are based on expert opinion and on relevant publications from PubMed and EMbase. The Clinical Practice Updates Committee of the American Gastroenterological Association proposes the following recommendations: 1) in determining the need for achalasia therapy, patient-specific parameters (Chicago Classification subtype, comorbidities, early vs late disease, primary or secondary causes) should be considered along with published efficacy data; 2) given the complexity of this procedure, POEM should be performed by experienced physicians in high-volume centers because an estimated 20-40 procedures are needed to achieve competence; 3) if the expertise is available, POEM should be considered as primary therapy for type III achalasia; 4) if the expertise is available, POEM should be considered as treatment option comparable with laparoscopic Heller myotomy for any of the achalasia syndromes; and 5) post-POEM patients should be considered high risk to develop reflux esophagitis and advised of the management considerations (potential indefinite proton pump inhibitor therapy and/or surveillance endoscopy) of this before undergoing the procedure.

Treatments for achalasia in 2017: how to choose among them

PURPOSE OF REVIEW

To review recent advances in achalasia diagnostics and therapeutics.

RECENT FINDINGS

The cardinal feature of achalasia, impaired lower esophageal sphincter (LES) relaxation, can occur in association with varied patterns of esophageal contractility. The Chicago Classification distinguishes among these as follows: without contractility (type I), with panesophageal pressurization (type II), with premature (spastic) distal esophageal contractions (type III), or even with preserved peristalsis [esophagogastric junction (EGJ) outlet obstruction]. Physiological testing also reveals achalasia-like syndromes that also benefit from achalasia therapies. Coincident with this has been the development of peroral endoscopic myotomy (POEM), an endoscopic technique for performing an esophageal myotomy. Hence, the option now exists to either selectively ablate the LES (pneumatic dilation, laparoscopic Heller myotomy, or POEM) or to ablate the sphincter and create a myotomy along some or the entire adjacent smooth muscle esophagus (POEM). Each achalasia syndrome has unique treatment considerations; type II achalasia responds well to all therapies, whereas type III responds best to POEM.

SUMMARY

Emerging data support the concept that optimal management of achalasia is phenotype-specific, guided by high-resolution manometry, and, in some instance, functional luminal imaging probe studies. This opinion article reviews the varied characteristic and treatment considerations of achalasia syndromes as currently understood.

Comparison of motor diagnoses by Chicago Classification versions 2.0 and 3.0 on esophageal high-resolution manometry

BACKGROUND

The Chicago Classification (CC) uses high-resolution manometry (HRM) software tools to designate esophageal motor diagnoses. We evaluated changes in diagnostic designations between two CC versions, and determined motor patterns not identified by either version.

METHODS

In this observational cohort study of consecutive patients undergoing esophageal HRM over a 6-year period, proportions meeting CC 2.0 and 3.0 criteria were segregated into esophageal outflow obstruction, hypermotility, and hypomotility disorders. Contraction wave abnormalities (CWA), and 'normal' cohorts were recorded. Symptom burden was characterized using dominant symptom intensity and global symptom severity. Motor diagnoses, presenting symptoms, and symptom burden were compared between CC 2.0 and 3.0, and in cohorts not meeting CC diagnoses.

KEY RESULTS

Of 2569 eligible studies, 49.9% met CC 2.0 criteria, but only 40.3% met CC 3.0 criteria (P<.0001). Between CC 2.0 and 3.0, 82.8% of diagnoses were concordant. Discordance resulted from decreasing proportions of hypermotility (4.4%) and hypomotility (9.0%) disorders, and increase in 'normal' designations (13.0%); esophageal outflow obstruction showed the least variation between CC versions. Symptom burden was higher with CC 3.0 diagnoses (P≤.005) but not with CC 2.0 diagnoses (P≥.1). Within 'normal' cohorts for both CC versions, CWA were associated with higher likelihood of esophageal symptoms, especially dysphagia, regurgitation, and heartburn, compared to truly normal studies (P≤.02 for each comparison).

CONCLUSIONS AND INFERENCES

Despite lower sensitivity, CC 3.0 identifies esophageal motor disorders with higher symptom burden compared to CC 2.0. CWA, which are associated with both transit and perceptive symptoms, are not well identified by either version.

Elevated intrabolus pressure identifies obstructive processes when integrated relaxation pressure is normal on esophageal high-resolution manometry

Elevated integrated relaxation pressure (IRP) on esophageal high-resolution manometry (HRM) identifies obstructive processes at the esophagogastric junction (EGJ). Our aim was to determine whether intrabolus pressure (IBP) can identify structural EGJ processes when IRP is normal. In this observational cohort study, adult patients with dysphagia and undergoing HRM were evaluated for endoscopic evidence of structural EGJ processes (strictures, rings, hiatus hernia) in the setting of normal IRP. HRM metrics [IRP, distal contractile integral (DCI), distal latency (DL), IBP, and EGJ contractile integral (EGJ-CI)] were compared among 74 patients with structural EGJ findings (62.8 ± 1.6 yr, 67.6% women), 27 patients with normal EGD (52.9 ± 3.2 yr, 70.3% women), and 21 healthy controls (27.6 ± 0.6 yr, 52.4% women). Findings were validated in 85 consecutive symptomatic patients to address clinical utility. In the primary cohort, mean IBP (18.4 ± 0.9 mmHg) was higher with structural EGJ findings compared with dysphagia with normal EGD (13.5 ± 1.1 mmHg, P = 0.002) and healthy controls (10.9 ± 0.9 mmHg, P < 0.001). However, mean IRP, DCI, DL, and EGJ-CI were similar across groups (P > 0.05 for each comparison). During multiple rapid swallows, IBP remained higher in the structural findings group compared with controls (P = 0.02). Similar analysis of the prospective validation cohort confirmed IBP elevation in structural EGJ processes, but correlation with dysphagia could not be demonstrated. We conclude that elevated IBP predicts the presence of structural EGJ processes even when IRP is normal, but correlation with dysphagia is suboptimal.NEW & NOTEWORTHY Integrated relaxation pressure (IRP) above the upper limit of normal defines esophageal outflow obstruction using high-resolution manometry. In patients with normal IRP, elevated intrabolus pressure (IBP) can be a surrogate marker for a structural restrictive or obstructive process at the esophagogastric junction (EGJ). This has the potential to augment the clinical value of esophageal HRM by raising suspicion for a structural EGJ process when IBP is elevated.

Esophagogastric Junction Contractility Integral Reflect the Anti-reflux Barrier Dysfunction in Patients with Gastroesophageal Reflux Disease

Background/Aims

Anti-reflux barrier dysfunction is one of the primary mechanisms in gastroesophageal reflux disease (GERD) pathogenesis. The esophagogastric junction contractile integral (EGJ-CI) is a new metric adopted to evaluate the EGJ contractility, which implies the anti-reflux barrier function. The aim of the current study was to validate this new metric in patients with GERD and its correlation with the esophageal acid exposure, as well as the efficacy of proton pump inhibitor treatment.

Methods

Ninety-eight patients with GERD and 21 healthy controls were included in the study. Upper endoscopy, high-resolution manometry (HRM) and 24-hour multichannel intraluminal impedance-pH monitoring were performed in all patients. Three respiration cycles were chosen at the initial HRM resting frame and the value computed with distal contractile integral tool was then divided by the duration of the cycles to yield EGJ-CI. All the patients were treated with esomeprazole 20 mg twice-daily for 8 weeks.

Results

EGJ-CI was lower in the patients with GERD than that of the controls (P < 0.05). For patients with GERD, EGJ-CI was lower in those with hiatal hernia (P < 0.05). The new metric correlated with esophageal acid exposure in the supine position (P < 0.05), and it also negatively correlated to the total reflux episodes (P < 0.05). There was no significant difference on EGJ-CI between patients with and without response to the esomeprazole treatment (P = 0.627).

Conclusions

EGJ-CI reflected the dysfunction of the anti-reflux barrier in patients with GERD, but it had little impact on the esomeprazole response.

The learning curve for interpretation of oesophageal high-resolution manometry: a prospective interventional cohort study

BACKGROUND

High-resolution manometry has become the preferred choice of oesophagologists for oesophageal motor assessment, but the learning curve among trainees remains unclear.

AIM

To determine the learning curve of high-resolution manometry interpretation.

METHODS

A prospective interventional cohort study was performed on 18 gastroenterology trainees, naïve to high-resolution manometry (median age 32 ± 4.0 years, 44.4% female). An intake questionnaire and a 1-h standardised didactic session were performed at baseline. Multiple 1-h interpretation sessions were then conducted periodically over 15 months where 10 studies were discussed; 5 additional test studies were provided for interpretation, and results were compared to gold standard interpretation by the senior author. Hypothetical management decisions based on trainee interpretation were separately queried. Accuracy was compared across test interpretations and sessions to determine the learning curve, with a goal of 90% accuracy.

RESULTS

Baseline accuracy was low for abnormal body motor patterns (53.3%), but higher for achalasia/outflow obstruction (65.9%). Recognition of achalasia reached 90% accuracy after six sessions (P = 0.01), while overall accurate management decisions reached this threshold by the 4th session (P < 0.001). Based on our data, the threshold of 90% accuracy for recognition of any abnormal from normal pattern was reached after 30 studies (3rd session) but fluctuated. Diagnosis of oesophageal body motor patterns remained suboptimal; accuracy of advisability of fundoplication improved, but did not reach 90%.

CONCLUSIONS

High-resolution manometry has a steep learning curve among trainees. Achalasia recognition is achieved early, but diagnosis of other abnormal motor patterns and management decisions require further supervised training.

Comparison of two high-resolution manometry software systems in evaluating esophageal motor function

BACKGROUND

High-resolution manometry (HRM) utilizes software tools to diagnose esophageal motor disorders. Performance of these software metrics could be affected by averaging and by software characteristics of different manufacturers.

METHODS

High-resolution manometry studies on 86 patients referred for antireflux surgery (61.6 ± 1.4 year, 70% F) and 20 healthy controls (27.9 ± 0.7 year, 45% F) were first subject to standard analysis (Medtronic, Duluth, GA, USA). Coordinates for each of 10 test swallows were exported and averaged to generate a composite swallow. The swallows and averaged composites were imported as ASCII file format into Manoview (Medtronic) and Medical Measurement Systems database reporter (MMS, Dover, NH, USA), and analyses repeated. Comparisons were made between standard and composite swallow interpretations.

KEY RESULTS

Correlation between the two systems was high for mean distal contractile integral (DCI, r² ≥ 0.9) but lower for integrated relaxation pressure (IRP, r² = 0.7). Excluding achalasia, six patients with outflow obstruction (mean IRP 23.2 ± 2.1 with 10-swallow average) were identified by both systems. An additional nine patients (10.5%) were identified as outflow obstruction (15 mmHg threshold) with MMS 10-swallow and four with MMS composite swallow evaluation; only one was confirmed. Ineffective esophageal motility was diagnosed by 10-swallow evaluation in 19 (22.1%) with Manoview, and 20 (23.3%) with MMS. On Manoview composite, 17 had DCI <450 mmHg/cm/s, and on MMS composite, 21, (p ≥ 0.85 for each comparison) but these did not impact diagnostic conclusions.

CONCLUSIONS & INFERENCES

Comparison of 10 swallow and composite swallows demonstrate variability in software metrics between manometry systems. Our data support use of manufacturer specific software metrics on 10-swallow sequences.

Identification of Quality Measures for Performance of and Interpretation of Data From Esophageal Manometry

BACKGROUND & AIMS

Esophageal manometry is the standard for the diagnosis of esophageal motility disorders. Variations in the performance and interpretation of esophageal manometry result in discrepant diagnoses and unnecessary repeated procedures, and could have negative effects on patient outcomes. We need a method to benchmark the procedural quality of esophageal manometry; as such, our objective was to formally develop quality measures for the performance and interpretation of data from esophageal manometry.

METHODS

We used the RAND University of California Los Angeles Appropriateness Method (RAM) to develop validated quality measures for performing and interpreting esophageal manometry. The research team identified potential quality measures through a literature search and interviews with experts. Fourteen experts in esophageal manometry ranked the proposed quality measures for appropriateness via a 2-round process on the basis of RAM.

RESULTS

The experts considered a total of 29 measures; 17 were ranked as appropriate and were as follows: related to competency (2), assessment before the esophageal manometry procedure (2), the esophageal manometry procedure itself (3), and interpretation of data (10). The data interpretation measures were integrated into a single composite measure. Eight measures therefore were found to be appropriate quality measures for esophageal manometry . Five other factors also were endorsed by the experts, although these were not ranked as appropriate quality measures.

CONCLUSIONS

We identified 8 formally validated quality measures for the performance and interpretation of data from esophageal manometry on the basis of RAM. These measures represent key aspects of a high-quality esophageal manometry study and should be adopted uniformly. These measures should be evaluated in clinical practice to determine how they affect patient outcomes.

[Current issues on gastroesophageal reflux disease]

Gastroesophageal reflux disease (GERD) is one of the most common problems in gastrointestinal disorders. With the increase in our understanding on the pathophysiology of GERD along with the development of proton pump inhibitors, the diagnostic and therapeutic approaches to GERD have changed dramatically over the past decade. However, GERD still poses a problem to many clinicians since the spectrum of the disease has evolved to encompass more challenging presentations such as refractory GERD and extraesophageal manifestations. This has led to significant confusion regarding the optimal approach to these patients. This article aims to discuss current issues on GERD.

Approach to the patient with dysphagia

Dysphagia is a fascinating symptom. It is ostensibly simple when defined by trouble swallowing, yet its subtleties in deciphering and its variations in pathophysiology almost mandate a thorough knowledge of medicine itself. With patience and careful questioning, a multitude of various disorders may be suggested before an objective test is performed. Indeed, the ability to diligently and comprehensively explore the symptom of dysphagia is not only rewarding but also a real test for a physician who prides himself or herself on good history taking.

The Chicago Classification of esophageal motility disorders, v3.0

BACKGROUND

The Chicago Classification (CC) of esophageal motility disorders, utilizing an algorithmic scheme to analyze clinical high-resolution manometry (HRM) studies, has gained acceptance worldwide.

METHODS

This 2014 update, CC v3.0, developed by the International HRM Working Group, incorporated the extensive clinical experience and interval publications since the prior (2011) version.

KEY RESULTS

Chicago Classification v3.0 utilizes a hierarchical approach, sequentially prioritizing: (i) disorders of esophagogastric junction (EGJ) outflow (achalasia subtypes I-III and EGJ outflow obstruction), (ii) major disorders of peristalsis (absent contractility, distal esophageal spasm, hypercontractile esophagus), and (iii) minor disorders of peristalsis characterized by impaired bolus transit. EGJ morphology, characterized by the degree of overlap between the lower esophageal sphincter and the crural diaphragm and baseline EGJ contractility are also part of CC v3.0. Compared to the previous CC version, the key metrics of interpretation, the integrated relaxation pressure (IRP), the distal contractile integral (DCI), and the distal latency (DL) remain unchanged, albeit with much more emphasis on DCI for defining both hypo- and hypercontractility. New in CC v3.0 are: (i) the evaluation of the EGJ at rest defined in terms of morphology and contractility, (ii) 'fragmented' contractions (large breaks in the 20-mmHg isobaric contour), (iii) ineffective esophageal motility (IEM), and (iv) several minor adjustments in nomenclature and defining criteria. Absent in CC v3.0 are contractile front velocity and small breaks in the 20-mmHg isobaric contour as defining characteristics.

CONCLUSIONS & INFERENCES

Chicago Classification v3.0 is an updated analysis scheme for clinical esophageal HRM recordings developed by the International HRM Working Group.

Esophageal motor function: technical aspects of manometry

High-resolution manometry (HRM) has advanced the understanding of esophageal peristaltic mechanisms and has simplified esophageal motor testing. In this article the technical aspects of HRM are addressed, focusing on test protocols, in addition to concerns and pitfalls in performing esophageal motor studies. Specifically, catheter positioning, equipment-related artifacts, basal data acquisition, adequate swallows, and provocative maneuvers are discussed.

A novel high-resolution anorectal manometry parameter based on a three-dimensional integrated pressurized volume of a spatiotemporal plot, for predicting balloon expulsion in asymptomatic normal individuals

BACKGROUND

Anorectal manometry with simulated evacuation (SE) has limited applicability in predicting balloon expulsion (BE) test results. The newly developed high-resolution anorectal manometry (HRAM) technique can yield spatiotemporal plots with three-dimensional pressurization. We aimed to define new parameters based on three-dimensional integrated pressurized volume (IPV) for predicting the BE test results in asymptomatic normal individuals.

METHODS

Fifty-four asymptomatic healthy individuals were prospectively enrolled. BE tests were performed using 50 mL of water, and a requirement of more than 1 min was considered as delayed BE. HRAM profiles were converted into ASCII files and analyzed using a MATLAB program. A three-dimensional IPV was plotted after transforming the data to a cubic spline interpolation followed by resampling the manometry position at 0.1-cm intervals.

KEY RESULTS

Eight of the 54 (15%) individuals demonstrated delayed BE. Conventional manometric profiles did not differ significantly between cases of early and delayed BE. Receiver-operator characteristic curve analysis revealed that the ratio of the IPVs of the upper 1 cm to the lower 4 cm of the anorectal canal with balloon distension was more predictable of the BE results (area under curve, 0.73: 95% confidence interval, 0.53-0.92; p = 0.04) than the other IPVs or their ratios.

CONCLUSIONS & INFERENCES

The newly developed IPV methods could predict delayed BE tests during SE better than the conventional parameters defined on the basis of linear waves. Well-designed prospective trials on a large number of subjects are warranted to validate the clinical application of this novel parameter.

Esophageal manometry in gastroesophageal reflux disease

High-resolution manometry (HRM) allows nuanced evaluation of esophageal motor function, and more accurate evaluation of lower esophageal sphincter (LES) function, in comparison with conventional manometry. Pathophysiologic correlates of gastroesophageal reflux disease (GERD) and esophageal peristaltic performance are well addressed by this technique. HRM may alter the surgical decision by assessment of esophageal peristaltic function and exclusion of esophageal outflow obstruction before antireflux surgery. Provocative testing during HRM may assess esophageal smooth muscle peristaltic reserve and help predict the likelihood of transit symptoms following antireflux surgery. HRM represents a continuously evolving new technology that compliments the evaluation and management of GERD.

Systematic analysis of esophageal pressure topography in high-resolution manometry of 68 normal volunteers

The introduction of high-resolution manometry (HRM) has been a significant advance in esophageal diagnostics. Normative values however are currently based upon a single set of published reference values, and multiple new metrics have been added over the past several years. Our goal was to provide a second set of 'normal-values' and to include all current metrics suggested by the 2012 Chicago classification. Sixty-eight subjects without foregut symptoms or previous surgery (median age 25.5 years, ranging from 20-58 years, 53% female) underwent esophageal motility assessment via an established standardized protocol. Normative thresholds were calculated for esophago-gastric junction (EGJ) characteristics (resting, relaxation, intrabolus pressure, and lengths) as well as for esophageal body strength (contraction amplitudes at multiple levels, distal contractile integral, integrity of peristalsis) and wave propagation (contractile front velocity, distal latency). Overall, our findings where strikingly similar to the previously described metrics derived from 75 control subjects of the Northwestern group. This suggests a high degree of reproducibility of HRM.