Value of spatiotemporal representation of manometric data

Intra- and Inter-observer Agreement of High Resolution Antroduodenal Manometry in Pediatric Patients Among Single Center Experts

OBJECTIVES

Studies in adults have suggested that high-resolution technology increases the diagnostic yield of antroduodenal manometry (ADM). However, there is no study comparing high-resolution with low-resolution ADM recordings as well as comparing the 2 types of high-resolution display [conventional line plot (CLP) and pressure topographic plots (PTP)]. We hypothesized that high-resolution ADM is a superior diagnostic modality with higher inter-observer and intra-observer agreement compared with low-resolution recordings.

METHODS

Twenty-four anonymized ADM studies were blindly analyzed by 3 experienced pediatric neurogastroenterologists. All studies had been performed using a low-compliance water-perfused system with a 20-channels catheter. Data were displayed as CLP, as both high-resolution and low-resolution, and PTP in different sessions with at least 6-week interval. Accuracy was evaluated using previous established diagnosis and specific pre-prandial and post-prandial manometric patterns. Inter-observer and intra-observer agreements were calculated.

RESULTS

Analysis with high-resolution CLP revealed a substantial inter-observer agreement among the 3 observers regarding the diagnosis (Krippendorff's alpha: 0.832; average pairwise percentage agreement: 88.9%). Conversely, PTP and low-resolution CLP showed poor agreement for diagnoses (Krippendorff's alpha: 0.600; average pairwise percentage agreement: 75.3%; Krippendorff's alpha: 0.390; average pairwise percentage agreement: 60.2%, respectively). For the intra-observer agreement, Krippendorff's alpha ranges were 0.891-1 for CLP and 0.19393-0.34621 for PTP.

CONCLUSIONS

Our study demonstrated higher diagnostic accuracy for high-resolution ADM compared to the low-resolution recordings. However, although it is well established for other motility investigations, PTP is not yet reliable in assessing foregut motor patterns. Advanced and more sophisticated software are clearly required for analyzing PTP display.

Esophageal motility abnormalities in Egyptian patients using high resolution esophageal manometry: a descriptive study

Background and aim

For many years, esophageal manometry has been used for assessment of upper gastro-intestinal (GI) symptoms. Chicago classification is the key for diagnosis and managing motility disorders as it is considered as a standardized approach for categorization of esophageal abnormalities. The aim of this study is to analyze types of esophageal motility findings in Egyptian cases who were suffering from upper GI complaints. Methods: This descriptive study included 378 subjects who were suffering from upper GI complaints as dysphagia, vomiting, chest pain and regurgitation in the period between 10/2015–7/2020. Esophageal HRM study was performed for all patients (MMS Laborie device). The catheter was positioned and confirmed passing across the EGJ (esophago-gastric junction) using landmarks. Swallows and resting status were recorded. Anatomical landmarks were placed.

Results

Most of the patients were complaining of upper GI symptoms. Males were 49.2% of cases. Mean age was 41.3. Dysphagia was the prominent symptom while chest pain was the least symptom. Many manometry findings were observed including ineffective motility, achalasia, absent contractility, EGJ outflow obstruction, jackhammer esophagus and normal findings. Type II achalasia was the dominant type in achalasia patients while Type III was the least. LES was normotensive in most of the cases. Hiatus hernia (HH) was detected in 40.2% of the cases.

Conclusion

This is considered the first Egyptian descriptive study to determine the prevalence of esophageal motility abnormalities in Egyptian patients complaining of upper GI symptoms. HRM is very important for patients complaining of upper GI symptoms.

The value of conventional manometry in the identification of normal esophageal manometry

In the last decade, high-resolution esophageal manometry (HREM) is the main device for the management of dysphagia replacing conventional manometry (CM). Conventional manometry still seems to have some space to diagnose major motility disorders and differentiate normal from abnormal esophageal motility. The long term outcomes of patients with normal CM were analyzed in our study.Participants (patients with dysphagia and normal CM) took a questionnaire via a phone call in February 2021. Impact Dysphagia Questionnaire (IDQ) was used as an assessment tool.Only 55% (83/151) the individuals with previous normal manometric findings were reached via telephone. The group who have completed the survey was representative of the cohort. 66.2% of the participants were female (P = .40). The mean age was 57.21, mean weight was 70.69 kg, mean height was 163.74 cm and mean body mass index was 26.41. More than 40% of patients were completely asymptomatic at follow up, reflected by an IDQ score of 0. Only 28 out of 83 (33.7%) patients reported significant symptoms as reflected by an IDQ score greater than or equal to 7. The rest of responders admitted as having moderate to mild symptoms.HREM is a valid technique with comparable precision to CM. HREM measurements differ considerably to CM. The identification of normal motor function in CM is not likely a positive prognostic indicator and must be interpreted precautiously.

European Society for Neurogastroenterology and Motility (ESNM) recommendations for the use of high-resolution manometry of the esophagus

BACKGROUND

Several patients in gastroenterology practice present with esophageal symptoms, and in case of normal endoscopy with biopsies, high-resolution manometry (HRM) is often the next step. Our aim was to develop a European consensus on the clinical application of esophageal HRM, to offer the clinician guidance in selecting patients for HRM and using its results to optimize clinical outcome.

METHODS

A Delphi consensus was initiated with 38 multidisciplinary experts from 16 European countries who conducted a literature summary and voting process on 71 statements. Quality of evidence was evaluated using grading of recommendations assessment, development, and evaluation (GRADE) criteria. Consensus (defined as >80% agreement) was reached for 33 statements.

RESULTS

The process generated guidance on when to consider esophageal HRM, how to perform it, and how to generate the report. The Delphi process also identified several areas of uncertainty, such as the choice of catheters, the duration of fasting and the position in which HRM is performed, but recommended to perform at least 10 5-ml swallows in supine position for each study. Postprandial combined HRM impedance is considered useful for diagnosing rumination. There is a large lack of consensus on treatment implications of HRM findings, which is probably the single area requiring future targeted research.

CONCLUSIONS AND INFERENCES

A multinational and multidisciplinary group of European experts summarized the current state of consensus on technical aspects, indications, performance, analysis, diagnosis, and therapeutic implications of esophageal HRM.

Chicago classification version 4.0© technical review: Update on standard high-resolution manometry protocol for the assessment of esophageal motility

The Chicago Classification v4.0 (CCv4.0) is the updated classification scheme for esophageal motility disorders using metrics from high-resolution manometry (HRM). A key feature of CCv.4.0 is the more rigorous and expansive protocol that incorporates single wet swallows acquired in different positions (supine, upright) and provocative testing, including multiple rapid swallows and rapid drink challenge. Additionally, solid bolus swallows, solid test meal, and/or pharmacologic provocation can be used to identify clinically relevant motility disorders and other conditions (eg, rumination) that occur during and after meals. The acquisition and analysis for performing these tests and the evidence supporting their inclusion in the Chicago Classification protocol is detailed in this technical review. Provocative tests are designed to increase the diagnostic sensitivity and specificity of HRM studies for disorders of esophageal motility. These changes attempt to minimize ambiguity in prior iterations of Chicago Classification, decrease the proportion of HRM studies that deliver inconclusive diagnoses and increase the number of patients with a clinically relevant diagnosis that can direct effective therapy. Another aim in establishing a standard manometry protocol for motility laboratories around the world is to facilitate procedural consistency, improve diagnostic reliability, and promote collaborative research.

High-Resolution Manometry-Observations After 15 Years of Personal Use-Has Advancement Reached a Plateau?

PURPOSE OF REVIEW

In the absence of mucosal or structural disease, the aim of investigating the oesophagus is to provide clinically relevant measurements of function that can explain the cause of symptoms, identify pathology and guide effective management. One of the most notable recent advances in the field of oesophageal function has been high-resolution manometry (HRM). This review explores how innovation in HRM has progressed and has far from reached a plateau.

RECENT FINDINGS

HRM technology, methodology and utility continue to evolve; simple additions to the swallow protocol (e.g. eating and drinking), shifting position, targeting symptoms and adding impedance sensors to the HRM catheter have led to improved diagnoses, therapeutic decision-making and outcomes. Progress in HRM persists and shows little sign of abating. The next iteration of the Chicago Classification of motor disorders will highlight these advances and will also identify opportunities for further research and innovation.

Prospective serial diagnostic study: the effects of position and provocative tests on the diagnosis of oesophageal motility disorders by high-resolution manometry

BACKGROUND

Standard high-resolution manometry (HRM) protocols are based on 10 single water swallows acquired in the supine position.

AIMS

To assess the impact of position, rapid drink challenge and solid test meal on the diagnosis of oesophageal motility disorders.

METHODS

Seventy-two healthy volunteers (20-76 years) and 366 consecutive patients (18-90 years) completed HRM with 10 single water swallows in the supine and upright positions. Rapid drink challenge was performed twice, before and after the solid test meal. Diagnosis based on single water swallows in the supine position (Chicago Classification v3.0) was compared with results in the upright position and with provocative tests.

RESULTS

Overall, diagnostic agreement in the supine and upright positions was present in 296/438 (67.6%) subjects. This increased to 90.0% when ineffective oesophageal motility was considered with normal motility. Integrated relaxation pressure was 4 mm Hg higher in the supine position. There was a higher prevalence of inconsistent, likely false positive, diagnoses of outlet obstruction in the supine compared to the upright position (16/20 vs 1/4 patients, P = 0.0007). Similarly, the difference in concordance for the diagnosis of oesophago-gastric junction obstruction or achalasia between single water swallows in the supine and upright positions with solid test meal was significant (12/29 (41.4%) vs 12/14 (85.7%), P = 0.0087).

CONCLUSION

Diagnostic agreement for oesophageal motility disorders based on single water swallows in the upright and supine positions was moderate, with frequent discordant findings for ineffective motility and outlet obstruction. HRM studies can be performed in either position, using appropriate reference values. Rapid drink challenge or solid test meal can resolve diagnostic discrepancies.

British Society of Gastroenterology guidelines for oesophageal manometry and oesophageal reflux monitoring

These guidelines on oesophageal manometry and gastro-oesophageal reflux monitoring supersede those produced in 2006. Since 2006 there have been significant technological advances, in particular, the development of high resolution manometry (HRM) and oesophageal impedance monitoring. The guidelines were developed by a guideline development group of patients and representatives of all the relevant professional groups using the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool. A systematic literature search was performed and the GRADE (Grading of Recommendations Assessment, Development and Evaluation) tool was used to evaluate the quality of evidence and decide on the strength of the recommendations made. Key strong recommendations are made regarding the benefit of: (i) HRM over standard manometry in the investigation of dysphagia and, in particular, in characterising achalasia, (ii) adjunctive testing with larger volumes of water or solids during HRM, (iii) oesophageal manometry prior to antireflux surgery, (iv) pH/impedance monitoring in patients with reflux symptoms not responding to high dose proton pump inhibitors and (v) pH monitoring in all patients with reflux symptoms responsive to proton pump inhibitors in whom surgery is planned, but combined pH/impedance monitoring in those not responsive to proton pump inhibitors in whom surgery is planned. This work has been endorsed by the Clinical Services and Standards Committee of the British Society of Gastroenterology (BSG) under the auspices of the oesophageal section of the BSG.

High-resolution anal manometry: Repeatability, validation, and comparison with conventional manometry

BACKGROUND

Accurate measurement of anal sphincter function is potentially of value in defining treatment of common pelvic floor disorders. The aim of this study was to establish repeatability and validate high-resolution anorectal manometry (HRAM) by comparison to conventional manometry (CM). Arising from this work would be definitive normal range data.

METHODS

Eighty healthy volunteers (40 female) underwent a test-retest repeatability study. A 16-channel water-perfused HRAM catheter was compared to an 8-channel conventional catheter using a station pull-through technique.

KEY RESULTS

High-resolution anorectal manometry had similar precision to conventional manometry when measuring resting pressure (intraclass correlation coefficient [ICC] 0.73 vs 0.68, HRAM vs CM) and squeeze increment (ICC 0.90 vs 0.94, HRAM vs CM). HRAM measured resting pressures 10% lower than CM and squeeze pressure 27% higher than CM.

CONCLUSIONS AND INFERENCES

High-resolution anorectal manometry is a valid technique with comparable precision to CM. HRAM measurements differ considerably to CM, and a new set of normal values must be used.

Advancements in the use of manometry and impedance testing for esophageal functional disorders

The utilization of high-resolution manometry (HRM) has enhanced our understanding and assessment of esophageal motor disorders. Moreover, the combination of impedance technology with HRM (HRIM) has further improved our knowledge of esophageal physiology and the clinical evaluation of dysmotility, thanks to the addition of accurate measurement of bolus transit. Areas covered. This paper provides an overview of current knowledge in the use of HRIM for the study of esophageal functional disorders by reporting mainly the results of many publications and several systematic reviews in this field. Expert opinion. HRIM has represented a relevant improvement in the assessment of esophageal motility and has required the development of new metrics, such as the esophageal impedance integral ratio, the bolus flow time, the nadir impedance pressure and the impedance bolus height, which increase the evaluation of esophageal bolus transit. An extension of impedance is represented by functional lumen imaging probe (FLIP), which determines the biophysical properties and the distensibility of the esophagus and permits to detect contractility patterns not seen on HRM alone. We eagerly wait for a new and fruitful iteration of the Chicago Classification, now in version 3.0, which can cover the ongoing clinical experience of HRIM.

A new understanding of the physiology and pathophysiology of colonic motility?

BACKGROUND

In recent years, high-resolution manometry has been used in an attempt to gain a greater insight into the physiology/pathophysiology of colonic contractile activity in healthy adults and patients with colonic motility disorders. New colonic motor patterns have been identified and characterized, however, the clinical significance of these findings remains undetermined.

PURPOSE

This review will assess the current literature on colonic high-resolution manometry and determine if this procedure has advanced our understanding of colonic motility. The limitations, future directions, and the potential of this technique to assess the effects of treatment upon colonic motor patterns will also be discussed.

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.

Pharyngeal swallowing and oesophageal motility during a solid meal test: a prospective study in healthy volunteers and patients with major motility disorders

BACKGROUND

The factors that determine how people eat when they are healthy or have disease have not been defined. We used high resolution manometry (HRM) to assess pharyngeal swallowing and oesophageal motility during ingestion of a solid test meal (STM) in healthy volunteers and patients with motility disorders.

METHODS

This study was based at University Hospital Zurich (Zürich, Switzerland). Healthy volunteers who responded to an advertisement completed HRM with ten single water swallows (SWS) in recumbent and upright positions followed by a 200 g rice STM in the upright position. Healthy volunteers were stratified for age and sex to ensure a representative population. For comparison, consecutive patients with major motility disorders on SWS and patients with dysphagia but no major motility disorders on SWS (disease controls) were selected from a database that was assembled prospectively; the rice meal data were analysed retrospectively. During STM, pharyngeal swallows were timed and oesophageal contractions were classified as representing normal motility or different types of abnormal motility in accordance with established metrics. Factors that could potentially be associated with eating speed were investigated, including age, sex, body-mass index, and presence of motility disorder. We compared diagnoses based on SWS findings, assessed with the Chicago Classification v3.0, with those based on STM findings, assessed with the Chicago Classification adapted for solids. These studies are registered with ClinicalTrials.gov, numbers NCT02407938 and NCT02397616.

FINDINGS

Between April 2, 2014, and May 13, 2015, 72 healthy volunteers were recruited and underwent HRM. Additionally, we analysed data from 54 consecutive patients with major motility disorders and 53 with dysphagia but no major motility disorders recruited between April 2, 2013, and Dec 18, 2014. We found important variations in oesophageal motility and eating speed during meal ingestion in healthy volunteers and patients. Increased time between swallows was accompanied by more effective oesophageal contractions (in healthy volunteers, 20/389 [5%] effective swallows at <4 s between swallows vs 586/900 [65%] effective swallows at >11 s between swallows, p<0·0001). Obstructive, spastic, or hypercontractile swallows were rare in healthy volunteers (total <1%). Patients with motility disorders ate slower than healthy volunteers (14·95 g [IQR 11-25] per min vs 32·9 g [25-40] per min, p<0·0001) and pathological oesophageal motility were reproduced when patients consumed the STM. In healthy volunteers, eating speed was associated only with frequency of swallows (slope 2·5 g per min per pharyngeal swallow per min [95% CI 1·1-4·0], p=0·0009), whereas in patients with dysphagia, it was correlated with frequency of effective oesophageal contractions (6·4 g per min per effective contraction per min [4·3-8·5], p<0·0001). Diagnostic agreement was good between the HRM with SWS and rice STM (intra-class correlation coefficient r=0·81, 95% CI 0·74-0·87, p<0·0001).

INTERPRETATION

Our results show normative values for pharyngeal swallowing and oesophageal motility in healthy volunteers. Detailed analysis of HRM data acquired during an STM shows that the rate-limiting factor for intake of solids in health is the frequency of pharyngeal swallowing and not oesophageal contractility. The reverse is true in patients with oesophageal motility disorders, in whom the frequency of effective oesophageal contractions determines eating speed.

FUNDING

University Hospital Zurich.

Impaired esophageal motor function in eosinophilic esophagitis

Eosinophilic esophagitis is a chronic immunoallergic inflammatory disease of the esophagus that represents a major cause of digestive morbidity among the pediatric and young adult populations. Despite the fact that key symptoms in adults include dysphagia and food impaction, many patients lack structural changes in the esophagus to account for their complaints, which suggests the presence of underlying motor disorders and esophageal distensibility impairment. In the last few years the esophageal motility of these patients has been studied using various approaches, most particularly high-resolution manometry, ambulatory manometry, and impedance planimetry. This review focuses on the most relevant findings and scientific evidence regarding esophageal motor disorders in eosinophilic esophagitis.

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.

High-Resolution Manometry Improves the Diagnosis of Esophageal Motility Disorders in Patients With Dysphagia: A Randomized Multicenter Study

OBJECTIVES

High-resolution manometry (HRM) might be superior to conventional manometry (CM) to diagnose esophageal motility disorders. We aimed to compare the diagnosis performed with HRM and CM and confirmed at 6 months in a multicenter randomized trial.

METHODS

Patients with unexplained dysphagia were randomized to undergo either CM or HRM. Motility disorders were diagnosed using the Castell and Spechler classification for CM and the Chicago classification for HRM. Diagnosis confirmation was based on clinical outcome and response to treatment after 6-month follow-up. The initial diagnosis and percentage of confirmed diagnoses were compared between the two arms (CM and HRM).

RESULTS

In total, 247 patients were randomized and 245 analyzed: 122 in the CM arm and 123 in the HRM arm. A manometric diagnosis was more frequently initially achieved with HRM than with CM (97% vs. 84%; P<0.01). Achalasia was more frequent in the HRM arm (26% vs. 12% in the CM arm; P<0.01) while normal examinations were more frequent in the CM arm (52% vs. 28% in the HRM arm; P<0.05). After follow-up, the initial diagnosis was confirmed in 89% of patients in the HRM arm vs. 81% in the CM arm (P=0.07). Finally, overall procedure tolerance was better with CM than with HRM (P<0.01).

CONCLUSIONS

This randomized trial demonstrated an improved diagnostic yield for achalasia with HRM compared with CM. Diagnoses tended to be more frequently confirmed in patients who underwent HRM, suggesting that esophageal motility disorders could be identified earlier with HRM than with CM (ClinicalTrial.gov, NCT01284894).

Characterization and follow-up of esophagogastric junction outflow obstruction detected by high resolution manometry

BACKGROUND

Esophagogastric junction outflow obstruction (EGJOO) is a newly described diagnostic entity growing in importance due to the use of high resolution manometry (HRM). There is little knowledge regarding its incidence, etiopathogeny, long-term evolution, and most suitable treatment. Our objective was to increase the awareness of EGJOO to optimize the management of these patients.

METHODS

We conducted a historical (retrospective and prospective) study of patients diagnosed with EGJOO using HRM combined with multichannel intraluminal impedance, comparing their manometric and impedance characteristics with those of a control group. Symptoms, etiology of obstruction, acid exposure, clinical course (and its associated factors), and response to treatment were also evaluated in the EGJOO group.

KEY RESULTS

Forty-four subjects were included (28 patients and 16 controls). Esophagogastric junction outflow obstruction patients presented incomplete esophageal transit more frequently than controls. Patients with structural obstruction had dysphagia more frequently than patients with functional obstruction, and different manometric, impedance, and pH-metric patterns. Over one-third of the EGJOO patients presented a spontaneous resolution of symptoms without EGJOO treatment. In the multivariate analysis, the variables associated with this spontaneous symptomatic resolution included typical symptoms of gastro-esophageal reflux disease or epigastralgia as the main symptom and resting or basal pressure of the upper esophageal sphincter <50 mmHg.

CONCLUSIONS & INFERENCES

The majority of EGJOO patients presented intact peristalsis which may compensate for the lack of EGJ relaxation. In the EGJOO patients presenting favorable factors associated with a spontaneous resolution of symptoms, invasive treatments should be considered with special caution. Structural etiologies are more amenable to management, while the remainder may improve without intervention.

Clinical Application of Esophageal High-resolution Manometry in the Diagnosis of Esophageal Motility Disorders

Esophageal high-resolution manometry (HRM) is replacing conventional manometry in the clinical evaluation of patients with esophageal symptoms, especially dysphagia. The introduction of HRM gave rise to new objective metrics and recognizable patterns of esophageal motor function, requiring a new classification scheme: the Chicago classification. HRM measurements are more detailed and more easily performed compared to conventional manometry. The visual presentation of acquired data improved the analysis and interpretation of esophageal motor function. This led to a more sensitive, accurate, and objective analysis of esophageal motility. In this review we discuss how HRM changed the way we define and categorize esophageal motility disorders. Moreover, we discuss the clinical applications of HRM for each esophageal motility disorder separately.

Diagnosis of Esophageal Motility Disorders: Esophageal Pressure Topography vs. Conventional Line Tracing

OBJECTIVES

Enhanced characterization of esophageal peristaltic and sphincter function provided by esophageal pressure topography (EPT) offers a potential diagnostic advantage over conventional line tracings (CLT). However, high-resolution manometry (HRM) and EPT require increased equipment costs over conventional systems and evidence demonstrating a significant diagnostic advantage of EPT over CLT is limited. Our aim was to investigate whether the inter-rater agreement and/or accuracy of esophageal motility diagnosis differed between EPT and CLT.

METHODS

Forty previously completed patient HRM studies were selected for analysis using a customized software program developed to perform blinded independent interpretation in either EPT or CLT (six pressure sensors) format. Six experienced gastroenterologists with a clinical focus in esophageal disease (attendings) and six gastroenterology trainees with minimal manometry experience (fellows) from three academic centers interpreted each of the 40 studies using both EPT and CLT formats. Rater diagnoses were assessed for inter-rater agreement and diagnostic accuracy, both for exact diagnosis and for correct identification of a major esophageal motility disorder.

RESULTS

The total group agreement was moderate (κ=0.57; 95% CI: 0.56-0.59) for EPT and fair (κ=0.32; 0.30-0.33) for CLT. Inter-rater agreement between attendings was good (κ=0.68; 0.65-0.71) for EPT and moderate (κ=0.46; 0.43-0.50) for CLT. Inter-rater agreement between fellows was moderate (κ=0.48; 0.45-0.50) for EPT and poor to fair (κ=0.20; 0.17-0.24) for CLT. Among all raters, the odds of an incorrect exact esophageal motility diagnosis were 3.3 times higher with CLT assessment than with EPT (OR: 3.3; 95% CI: 2.4-4.5; P<0.0001), and the odds of incorrect identification of a major motility disorder were 3.4 times higher with CLT than with EPT (OR: 3.4; 2.4-5.0; P<0.0001).

CONCLUSIONS

Superior inter-rater agreement and diagnostic accuracy of esophageal motility diagnoses were demonstrated with analysis using EPT over CLT among our selected raters. On the basis of these findings, EPT may be the preferred assessment modality of esophageal motility.

Inter- and intrarater reliability of the Chicago Classification in pediatric high-resolution esophageal manometry recordings

BACKGROUND

The Chicago Classification (CC) facilitates interpretation of high-resolution manometry (HRM) recordings. Application of this adult based algorithm to the pediatric population is unknown. We therefore assessed intra and interrater reliability of software-based CC diagnosis in a pediatric cohort.

METHODS

Thirty pediatric solid state HRM recordings (13M; mean age 12.1 ± 5.1 years) assessing 10 liquid swallows per patient were analyzed twice by 11 raters (six experts, five non-experts). Software-placed anatomical landmarks required manual adjustment or removal. Integrated relaxation pressure (IRP4s), distal contractile integral (DCI), contractile front velocity (CFV), distal latency (DL) and break size (BS), and an overall CC diagnosis were software-generated. In addition, raters provided their subjective CC diagnosis. Reliability was calculated with Cohen's and Fleiss' kappa (κ) and intraclass correlation coefficient (ICC).

KEY RESULTS

Intra- and interrater reliability of software-generated CC diagnosis after manual adjustment of landmarks was substantial (mean κ = 0.69 and 0.77 respectively) and moderate-substantial for subjective CC diagnosis (mean κ = 0.70 and 0.58 respectively). Reliability of both software-generated and subjective diagnosis of normal motility was high (κ = 0.81 and κ = 0.79). Intra- and interrater reliability were excellent for IRP4s, DCI, and BS. Experts had higher interrater reliability than non-experts for DL (ICC = 0.65 vs ICC = 0.36 respectively) and the software-generated diagnosis diffuse esophageal spasm (DES, κ = 0.64 vs κ = 0.30). Among experts, the reliability for the subjective diagnosis of achalasia and esophageal gastric junction outflow obstruction was moderate-substantial (κ = 0.45-0.82).

CONCLUSIONS & INFERENCES

Inter- and intrarater reliability of software-based CC diagnosis of pediatric HRM recordings was high overall. However, experience was a factor influencing the diagnosis of some motility disorders, particularly DES and achalasia.

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.

Inter-observer agreement for diagnostic classification of esophageal motility disorders defined in high-resolution manometry

High-resolution esophageal manometry (HRM) is a recent development used in the evaluation of esophageal function. Our aim was to assess the inter-observer agreement for diagnosis of esophageal motility disorders using this technology. Practitioners registered on the HRM Working Group website were invited to review and classify (i) 147 individual water swallows and (ii) 40 diagnostic studies comprising 10 swallows using a drop-down menu that followed the Chicago Classification system. Data were presented using a standardized format with pressure contours without a summary of HRM metrics. The sequence of swallows was fixed for each user but randomized between users to avoid sequence bias. Participants were blinded to other entries. (i) Individual swallows were assessed by 18 practitioners (13 institutions). Consensus agreement (≤ 2/18 dissenters) was present for most cases of normal peristalsis and achalasia but not for cases of peristaltic dysmotility. (ii) Diagnostic studies were assessed by 36 practitioners (28 institutions). Overall inter-observer agreement was 'moderate' (kappa 0.51) being 'substantial' (kappa > 0.7) for achalasia type I/II and no lower than 'fair-moderate' (kappa >0.34) for any diagnosis. Overall agreement was somewhat higher among those that had performed >400 studies (n = 9; kappa 0.55) and 'substantial' among experts involved in development of the Chicago Classification system (n = 4; kappa 0.66). This prospective, randomized, and blinded study reports an acceptable level of inter-observer agreement for HRM diagnoses across the full spectrum of esophageal motility disorders for a large group of clinicians working in a range of medical institutions. Suboptimal agreement for diagnosis of peristaltic motility disorders highlights contribution of objective HRM metrics.

Normal values for solid-state esophageal high-resolution manometry in a European population; an overview of all current metrics

BACKGROUND

Esophageal high-resolution manometry (HRM) allows accurate evaluation of esophageal motility. Normal values for HRM were established in the United States and several new parameters were introduced since. We aimed to provide a complete set of normal values for HRM obtained in a European population, including all current metrics used to describe the function of the upper esophageal sphincter (UES), the esophageal body, and the esophagogastric junction (EGJ).

METHODS

Fifty healthy volunteers underwent esophageal HRM. Subjects swallowed 10 liquid boluses in supine position, after which UES, EGJ, and contraction wave parameters were evaluated. Mean and median values with 5-95th percentile ranges were calculated.

KEY RESULTS

The normative thresholds (5-95th percentile) for the various parameters were; UES resting pressure 34.6-137.7 mmHg, UES residual pressure 0.0-8.5 mmHg, UES 0.2-s integrated relaxation pressure (IRP) 0.0-14.5 mmHg, EGJ length 3.1-6.3 cm, EGJ resting pressure 3.0-31.2 mmHg, EGJ 4-s IRP 2.0-15.5 mmHg, intrabolus pressure (IBP) 6.6-19.5 mmHg, distal contractile integral 178-2828 mmHg*s*cm, contractile front velocity (CFV) 2.9-5.9 cm s(-1) , distal latency 5.4-8.5 s, and transition zone length 0.0-8.2 cm.

CONCLUSIONS & INFERENCES

Most HRM parameters assessed in this study resemble the previously described values on which the current criteria are based, supporting the widespread use of these criteria for clinical purposes. However, vigor of the esophageal contraction was lower and transition zone length larger than in previous reports. Peristaltic breaks occur frequently in healthy subjects.

Manometric assessment of esophageal motor function in patients with primary biliary cirrhosis

INTRODUCTION/AIM

Primary biliary cirrhosis is associated with other autoimmune diseases including Sjögren's syndrome, and scleroderma. Esophageal dysmotility is well known in scleroderma, and Sjögren's syndrome. The aim of this study is to investigate whether any esophageal motor dysfunction exists in patients with primary biliary cirrhosis.

METHOD

The study was performed in 37 patients (36 women, mean age: 56.29 ± 10.01 years) who met diagnostic criteria for primary biliary cirrhosis. Thirty-seven functional dyspepsia patients, were also included as a control group. Patients entering the study were asked to complete a symptom questionnaire. Distal esophageal contraction amplitude, and lower esophageal sphincter resting pressure were assessed.

RESULTS

Manometric findings in primary biliary cirrhosis patients vs. controls were as follows: Median lower esophageal sphincter resting pressure (mmHg): (24 vs 20, p=0.033); median esophageal contraction amplitude (mmHg): (71 vs 56, p=0.050); mean lower esophageal sphincter relaxation duration (sc, x ± SD): (6.10 ± 1.18 vs 8.29 ± 1.92, p<0.001); and median lower esophageal sphincter relaxation (%) (96 vs 98, p=0.019); respectively. No significant differences were evident in median peak velocity (sc) (3.20 vs 3.02, p=0.778) between patients with primary biliary cirrhosis and the functional dyspepsia patients. Esophageal dysmotility was found in 17 (45.9%) primary biliary cirrhosis patients (non-specific esophageal motor disorder in ten patients, hypomotility of esophagus in five patients, nutcracker esophagus in one patient and hypertensive lower esophageal sphincter in one patient).

CONCLUSION

Esophageal dysmotility was detected in 45.9% of patients. The study suggests that subclinic esophageal dysmotility is frequent in patients with primary biliary cirrhosis.

High resolution esophageal manometry--the switch from "intuitive" visual interpretation to Chicago classification

High resolution esophageal manometry (HREM) has been interpreted all along by visual interpretation of color plots until the recent introduction of Chicago classification which categorises HREM using objective measurements. It compares HREM diagnosis of esophageal motor disorders by visual interpretation and Chicago classification. Using software Trace 1.2v, 77 consecutive tracings diagnosed by visual interpretation were re-analyzed by Chicago classification and findings compared for concordance between the two systems of interpretation.

STATISTICAL ANALYSIS

Kappa agreement rate between the two observations was determined. There were 57 males (74 %) and cohort median age was 41 years (range: 14-83 years). Majority of the referrals were for gastroesophageal reflux disease, dysphagia and achalasia. By "intuitive" visual interpretation, the tracing were reported as normal in 45 (58.4 %), achalasia 14 (18.2 %), ineffective esophageal motility 3 (3.9 %), nutcracker esophagus 11 (14.3 %) and nonspecific motility changes 4 (5.2 %). By Chicago classification, there was 100 % agreement (Kappa 1) for achalasia (type 1: 9; type 2: 5) and ineffective esophageal motility ("failed peristalsis" on visual interpretation). Normal esophageal motility, nutcracker esophagus and nonspecific motility disorder on visual interpretation were reclassified as rapid contraction and esophagogastric junction (EGJ) outflow obstruction by Chicago classification. Chicago classification identified distinct clinical phenotypes including EGJ outflow obstruction not identified by visual interpretation. A significant number of unclassified HREM by visual interpretation were also classified by it.

High resolution colonic manometry--what have we learnt?--A review of the literature 2012

Despite its size and physiological importance, the human colon is one of the least understood organs of the body. Many disorders arise from suspected abnormalities in colonic contractions, yet, due largely to technical constraints, investigation of human colonic motor function still remains relatively primitive. Most measures of colonic motility focus upon the transit speed (radiology, scintigraphy and, more recently, "smart pills"); however, only colonic manometry can measure pressure/force from multiple regions within the colon in real time (Dinning and Scott (Curr Opin Pharmacol 11:624-629, 2011)). Based upon data from colonic manometry studies, a number of different colonic motor patterns have been distinguished: (1) antegrade high amplitude propagating sequences (contractions), (2) low amplitude propagating sequences, (3) non-propagating contractions, and (4) and rarely episodes of retrograde (oral) propagating pressure waves (Dining and Di Lorenzo (Best Pract Res Clin Gastrolenterol 25(1): 89-101, 2011)). Abnormalities in the characteristics of these motor patterns should help to characterize dysmotility in a patient populations, and in both adults and children colonic motor abnormalities have been identified with manometry studies (Rao et al. Am J Gastroenterol 99(12):2405-2416, (2004), Di Lorenzo et al. Gut. 34(1): 803-807, (1993)). Yet, despite more than two decades of such studies, the clinical utility of colonic manometry remains marginal with no specific manometric biomarkers of colonic dysfunction being established ([Camilleri et al. Neurogastroenterol Motil. 20(12): 1269-1282, 2008). This has been highlighted recently in a colonic manometry study by Singh et al. (2013), in which 41 % of 80 patients, with confirmed slow transit constipation, were reported to have normal motility. While this may suggest that no motor abnormalities exist in a proportion of such patients, the finding may also reflect technical constraints in our ability to detail colonic motility patterns.

Low-resolution colonic manometry leads to a gross misinterpretation of the frequency and polarity of propagating sequences: Initial results from fiber-optic high-resolution manometry studies

BACKGROUND

High-resolution manometry catheters are now being used to record colonic motility. The aim of this study was to determine the influence of pressure sensor spacing on our ability to identify colonic propagating sequences (PS).

METHODS

Fiber-optic catheters containing 72-90 sensors spaced at 1 cm intervals were placed colonoscopically to the cecum in 11 patients with proven slow transit constipation, 11 patients with neurogenic fecal incontinence and nine healthy subjects. A 2 h section of trace from each subject was analyzed. Using the 1 cm spaced data as the gold standard, each data set was then sub-sampled, by dropping channels from the data set to simulate sensor spacing of 10, 7, 5, 3, and 2 cm. In blinded fashion, antegrade and retrograde PS were quantified at each test sensor spacing. The data were compared to the PSs identified in the corresponding gold standard data set.

KEY RESULTS

In all subject groups as sensor spacing increased; (i) the frequency of identified antegrade and retrograde PSs decreased (P < 0.0001); (ii) the ratio of antegrade to retrograde PSs increased (P < 0.0001); and (iii) the number of incorrectly labeled PSs increased (P < 0.003).

CONCLUSIONS & INFERENCES

Doubling the sensor spacing from 1 to 2 cm nearly halves the number of PSs detected. Tripling the sensor spacing from 1 to 3 cm resulted in a 30% chance of incorrectly labeling PSs. Closely spaced pressure recording sites (<2 cm) are mandatory to avoid gross misrepresentation of the frequency, morphology, and directionality of colonic propagating sequences.

High-resolution manometry changes our views of gastrointestinal motility

High-resolution manometry using catheters with 36 solid-state sensors spaced 1 cm apart has already become an established technique for esophageal manometry where it has replaced water-perfused and station pull-through manometry. Spatiotemporal plots with color coding of pressure have greatly facilitated the analysis of esophageal peristalsis. Although suitable for the length of the esophagus, the solid-state catheter is insufficient for the study of longer segments of the gastrointestinal tract. A new technique with fiber-optic sensors has made it possible to construct catheters with 72-144 sensors. Studies of colonic motility have revealed that the most common motor pattern of the colon is a peristaltic contraction that travels 7-10 cm in the retrograde direction. Earlier studies using low-resolution manometry with 7-45 cm between sensors led us to erroneous conclusions regarding direction and frequency of contractions and they largely missed both antegrade and retrograde contractions traveling short distances. Fiber-optic high-resolution manometry holds promise for greatly improving our understanding of gut motor physiology and hopefully also our understanding of patients with symptoms of disordered gut motility.

Evaluation of esophageal motor function in clinical practice

Esophageal motor function is highly coordinated between central and enteric nervous systems and the esophageal musculature, which consists of proximal skeletal and distal smooth muscle in three functional regions, the upper and lower esophageal sphincters, and the esophageal body. While upper endoscopy is useful in evaluating for structural disorders of the esophagus, barium esophagography, radionuclide transit studies, and esophageal intraluminal impedance evaluate esophageal transit and partially assess motor function. However, esophageal manometry is the test of choice for the evaluation of esophageal motor function. In recent years, high-resolution manometry (HRM) has streamlined the process of acquisition and display of esophageal pressure data, while uncovering hitherto unrecognized esophageal physiologic mechanisms and pathophysiologic patterns. New algorithms have been devised for analysis and reporting of esophageal pressure topography from HRM. The clinical value of HRM extends to the pediatric population, and complements preoperative evaluation prior to foregut surgery. Provocative maneuvers during HRM may add to the assessment of esophageal motor function. The addition of impedance to HRM provides bolus transit data, but impact on clinical management remains unclear. Emerging techniques such as 3-D HRM and impedance planimetry show promise in the assessment of esophageal sphincter function and esophageal biomechanics.

Interobserver variability in esophageal body measurements with high-resolution manometry among new physician users

GOALS

To evaluate interobserver variability among 4 new physician users on measures of esophageal body function.

BACKGROUND

Esophageal high-resolution manometry allows observation of esophageal motility by pressure topography plots. Little is known about the interobserver variability among physicians.

STUDY

Two resident and 2 fellow level physicians each interpreted 10 liquid swallows of 20 esophageal high-resolution manometry studies (n = 200 swallows) using the BioVIEW Analysis Suite (Sandhill Scientific Inc.). Studies evaluated were from patients referred for evaluation of dysphagia but found to have normal esophageal manometry and complete liquid bolus transit. Physicians received an orientation session and reviewed recent literature. Each physician recorded contractile front velocity (CFV) and distal contractile integral (DCI) for each liquid swallow.

STATISTICS

Interobserver agreements for CFV and DCI were assessed by intraclass correlation (ICC) values. Linear correlations between measurements by 2 readers were assessed using linear regression modeling techniques.

RESULTS

CFV and DCI values of up to 200 data points were analyzed. Four reader results for CFV and DCI showed strong agreement although stronger for DCI measures (ICC = 0.94; range, 0.91 to 0.98) in comparison with CFV (ICC = 0.79; range, 0.52 to 0.82). Further correlation was performed with 2 readers; readers 1 and 2 revealed excellent correlation for DCI (r = 0.95, P < 0.001) and good correlation for CFV (r = 0.61, P < 0.001).

CONCLUSIONS

With a thorough orientation session, good to excellent agreement for CFV and DCI measurements can be obtained from new physician users. CFV measures exhibit greater interobserver variability possibly due to the artifact produced by intraesophageal pressurization.

Clinical applications of esophageal impedance monitoring and high-resolution manometry

Esophageal impedance monitoring and high-resolution manometry (HRM) are useful tools in the diagnostic work-up of patients with upper gastrointestinal complaints. Impedance monitoring increases the diagnostic yield for gastroesophageal reflux disease in adults and children and has become the gold standard in the diagnostic work-up of reflux symptoms. Its role in the work-up for belching disorders and rumination seems promising. HRM is superior to other diagnostic tools for the evaluation of achalasia and contributes to a more specific classification of esophageal disorders in patients with non-obstructive dysphagia. The role of HRM in patients with dysphagia after laparoscopic placement of an adjustable gastric band seems promising. Future studies will further determine the clinical implications of the new insights which have been acquired with these techniques. This review aims to describe the clinical applications of impedance monitoring and HRM.

Technical aspects of clinical high-resolution manometry studies

A number of commercial and research systems are available for making high-resolution manometry recordings. purpose: In this document, we review the standard equipment, patient preparation and routine protocol for high-resolution manometry. The major differences between HRM systems lie in the method of signal transduction, with solid-state catheter systems recording form intraluminal transducers and water perfusion systems recording pressures from external transducers via a perfused silicone catheter. The variations in recording systems result in different mechanical and electrical characteristics which dictate different techniques for setting up and using equipment. These issues are relevant in terms of costs and day to day management, but have little clinical significance. After the equipment is prepared for a manometric study, the esophagus is intubated transnasally with the manometric catheter and the catheter is positioned so that the UES and LES/diaphragm are visualized on the recording screen. The subject then undergoes 10 5 ml water swallows in the supine position. Manometric data may be integrated with other data streams such as multichannel impedance or images from fluoroscopy to increase the power of the technique in difficult cases.

High-resolution manometry studies are frequently imperfect but usually still interpretable

BACKGROUND & AIMS

Clinical esophageal manometry can be technically challenging. We investigated the prevalence and causes of technically imperfect, high-resolution esophageal pressure topography (EPT) studies at a tertiary referral hospital.

METHODS

We reviewed 2000 consecutive clinical EPT studies that had been performed with consistent technique and protocol. A study was considered technically imperfect if there was a problem with pressure signal acquisition, if the catheter did not pass through the esophagogastric junction (EGJ), or if there were fewer than 7 evaluable swallows (without double-swallowing, and so forth). Data from the technically imperfect studies were interpreted blindly to determine a diagnosis; this diagnosis was compared with the diagnosis based on chart review.

RESULTS

We identified 414 technically imperfect studies (21% of the series). These were attributed to fewer than 7 evaluable swallows (58%), inability to traverse the EGJ (29%), sensor or thermal compensation malfunction (7%), and miscellaneous artifacts (6%). The most frequent causes of failure to traverse the EGJ were a large hiatal hernia (50%) and achalasia (24%). The condition most frequently associated with an incomplete swallow protocol was achalasia (33%). Despite the limitations, the diagnosis of achalasia was achieved correctly by blinded interpretation in 77% of cases and nonblinded interpretation in 94% of cases.

CONCLUSIONS

Technically imperfect EPT studies are common in a tertiary care center; large hiatal hernia and achalasia were the most frequent causes. However, despite the technical limitations, the data still could be interpreted, especially in the context of associated endoscopic and radiographic data.

High resolution manometry to detect transient lower oesophageal sphincter relaxations: diagnostic accuracy compared with perfused-sleeve manometry, and the definition of new detection criteria

BACKGROUND

Inhibition of transient lower oesophageal sphincter relaxations (tLESRs) has become one of the most relevant therapeutic objectives in patients with reflux symptoms resistant to proton pump inhibitors. tLESRs are currently detected by oesophageal perfused-sleeve manometry (PSM), but oesophageal high resolution manometry (HRM), which combines closely spaced pressure sensors and oesophageal pressure topography plots, may prove to be a better tool.

AIM

To evaluate the efficacy, reproducibility and interobserver agreement of HRM for the detection of tLESRs, in comparison with PSM.

METHODS

Twenty-four healthy volunteers underwent HRM alone and on a separate occasion with PSM simultaneously. LES pressure was monitored for 1 h during fasting and 2 h postprandial. Criteria for tLESRs were defined by characterising spontaneous LES relaxation associated with common cavity and then applied to all spontaneous LES relaxations. Interobserver agreement and the rates of tLESRs detected by HRM and PSM were compared.

RESULTS

New HRM criteria for the detection of tLESRs have been established. A similar number of tLESRs were identified during the two HRM recordings (median per subject 15 and 13 (P = 0.07) and less with PSM (median per subject 11, P < 0.01). The overall concordance rate between the two procedures was substantial (kappa = 0.61). The interobserver agreement was almost perfect (kappa = 0.83) with HRM and only fair (kappa = 0.38) with PSM.

CONCLUSIONS

High resolution manometry is reproducible and more sensitive than PSM to detect tLESRs. HRM provides a better interobserver agreement. These results confirm that HRM is the gold standard for detecting tLESRs (NTC00931593).

Normative values and inter-observer agreement for liquid and solid bolus swallows in upright and supine positions as assessed by esophageal high-resolution manometry

BACKGROUND

High-resolution manometry (HRM) with spatiotemporal representation of pressure data is a recent advance in esophageal measurement. At present, normal values are available for 5mL water swallows in the supine position. This study provides reference values for liquid and solid bolus swallows in the upright seated and supine positions.

METHODS

A total of 23 asymptomatic volunteers (11M:12F, age 20-56) underwent HRM (Manoscan 360; Sierra Scientific Instruments) with 5mL water and 1cm3 bread swallows in the upright and supine positions. Normal values for primary parameters associated with effective bolus transport [proximal transition zone length (PTZ, assesses peristaltic coordination], contraction front velocity (CFV), distal contractile index (DCI) and integrated relaxation pressure (IRP)] are presented. For each parameter, median values along with the 5-95th percentile range are reported. Inter-observer agreement between independent observers is reported using the intra-class correlation coefficient.

KEY RESULTS

A higher proportion of swallows were peristaltic for liquids than solids in both the upright and supine positions (both P<0.05). As workload increases with solid bolus and on moving from the upright to the supine position the esophageal contractile response resulted in a shorter PTZ, a slower CFV, and a more vigorous DCI. Also IRP increased during solid bolus transit (all P<0.01). There was significant agreement between independent observers for HRM parameters.

CONCLUSIONS & INFERENCES

Normative values for esophageal function for solids as well as liquids and in the 'physiologic', upright position will optimize the utility of HRM studies. The high level of inter-observer agreement indicates that these can be applied as reference values in clinical practice.

High-resolution manometric characteristics help differentiate types of distal esophageal obstruction in patients with peristalsis

BACKGROUND

High-resolution manometry (HRM) can identify obstructive motor features at the esophagogastric junction and abnormalities in esophageal bolus transit. We sought to determine if HRM patterns can differentiate functional from organic mechanical lower esophageal sphincter (LES) obstruction.

METHODS

Segmental characteristics of peristalsis were examined using HRM in symptomatic subjects with elevated postdeglutitive residual pressure gradients across the LES (≥5mmHg). Sixteen consecutive patients with non-achalasic mechanical fixed obstruction were compared with 13 patients with elevated pressure gradients yet no mechanical obstruction and 14 asymptomatic controls. Pressure volumes were determined in mmHg cm s for peristaltic segments defined on HRM Clouse plots using an on-screen pressure volume measurement tool.

KEY RESULTS

Residual pressure gradients were similarly elevated in both patient groups. A visually conspicuous and distinctive shift in the proportionate pressure strengths of the second and third peristaltic segments was apparent across groups. Whereas the ratios of peak pressures and pressure volumes between second and third segments approached 1 in controls (0.92, 0.98), pressures shifted to the second segment in mechanical obstruction (peak pressure ratio: 1.2±0.4; pressure volume ratio: 1.8±0.9) and to the third segment in functional obstruction (peak ratio: 0.7±0.2; volume ratio: 0.5±0.2; P<0.02 for any comparison of either group with controls). A threshold volume ratio of 1.0 correctly segregated 93% of obstruction (P<0.0001); visual pattern inspection was equally effective.

CONCLUSIONS & INFERENCES

When elevated residual pressure gradients are present in non-achalasic patients, topographic characteristics of peristalsis can differentiate fixed mechanical obstruction from functional obstruction.

High-resolution esophageal pressure topography is superior to conventional sleeve manometry for the detection of transient lower esophageal sphincter relaxations associated with a reflux event

BACKGROUND

Transient lower esophageal sphincter relaxations (TLESRs) are the main mechanism underlying gastro-esophageal reflux and are detected during manometric studies using well defined criteria. Recently, high-resolution esophageal pressure topography (HREPT) has been introduced and is now considered as the new standard to study esophageal and lower esophageal sphincter (LES) function. In this study we performed a head-to-head comparison between HREPT and conventional sleeve manometry for the detection of TLESRs.

METHODS

A setup with two synchronized MMS-solar systems was used. A solid state HREPT catheter, a water-perfused sleeve catheter, and a multi intraluminal impedance pH (MII-pH) catheter were introduced in 10 healthy volunteers (M6F4, age 19-56). Subjects were studied 0.5 h before and 3 h after ingestion of a standardized meal. Tracings were blinded and analyzed by the three authors according to the TLESR criteria.

KEY RESULTS

In the HREPT mode 156 TLESRs were scored, vs 143 during sleeve manometry (P = 0.10). Hundred and twenty-three TLESRs were scored by both techniques. Of all TLESRs (177), 138 were associated with reflux (78%). High-resolution esophageal pressure topography detected significantly more TLESRs associated with a reflux event (132 vs 119, P = 0.015) resulting in a sensitivity for detection of TLESRs with reflux of 96% compared to 86% respectively. Analysis of the discordant TLESRs associated with reflux showed that TLESRs were missed by sleeve manometry due to low basal LES pressure (N = 5), unstable pharyngeal signal (N = 4), and residual sleeve pressure >2 mmHg (N = 10).

CONCLUSIONS & INFERENCES

The HREPT is superior to sleeve manometry for the detection of TLESRs associated with reflux. However, rigid HREPT criteria are awaited.

Anatomical registration and three-dimensional visualization of low and high-resolution pan-colonic manometry recordings

BACKGROUND

Colonic propagating sequences (PS) are important for the movement of colonic content and defecation, and aberrant PS patterning has been associated with slow transit constipation. However, because these motor patterns are typically recorded over long periods (24 h +), the visualization of PS spatiotemporal patterning is difficult. Here, we develop a novel method for displaying pan-colonic motility patterns.

METHODS

A 3D mesh representing the geometry of the human colon was created as follows: (i) Human colon images from the Visible Human Dataset were digitized to create a 3D data cloud, and (ii) A surface mesh was fitted to the cloud using a least-squares minimization technique. Colonic manometry catheters were placed in the ascending colon of healthy controls and patients with slow transit constipation (STC), with the aid of a colonoscope. The colonic manometry data were interpolated and mapped to the model according to the following anatomical landmarks: cecum, hepatic flexure, splenic flexure, sigmoid-descending junction, and anus.

KEY RESULTS

These 3D images clearly and intuitively communicate characteristics of normal and abnormal colonic motility. Specifically we have shown the reduced amplitude of the antegrade propagating pressure waves (PPW) throughout the colon and reduced frequency of PPWs at the mid-colon in patients with STC.

CONCLUSIONS AND INFERENCES

A novel method for the 3D visualization of PS is presented, providing an intuitive method for representing a large volume of physiological data. These techniques can be used to display frequency, amplitude or velocity data, and will help to convey regions of abnormally in patient populations.

Esophageal motor disorders in terms of high-resolution esophageal pressure topography: what has changed?

The concept of high-resolution manometry (HRM) is to use sufficient pressure sensors such that intraluminal pressure can be monitored as a continuum along luminal length much as time is viewed as a continuum in conventional manometry. When HRM is coupled with pressure topography plots, pressure amplitude is transformed into spectral colors with isobaric conditions indicated by same-colored regions on the display. Together, these technologies are called high-resolution esophageal pressure topography (HREPT). HREPT has several advantages compared with conventional manometry, the technology that it was designed to replace. (i) The contractility of the entire esophagus can be viewed simultaneously in a uniform format, (ii) standardized objective metrics can be systematically applied for interpretation, and (iii) topographic patterns of contractility are more easily recognized and have greater reproducibility than with conventional manometry. Compared with conventional manometry, HREPT has improved sensitivity for detecting achalasia, largely due to the objectivity and accuracy with which it identifies impaired esophagogastric junction (EGJ) relaxation. In addition, it has led to the subcategorization of achalasia into three clinically relevant subtypes based on the contractile function of the esophageal body: classic achalasia, achalasia with esophageal compression, and spastic achalasia. Headway has also been made in understanding hypercontractile conditions, including diffuse esophageal spasm and a newly described entity, spastic nutcracker. Ultimately, clinical experience will be the judge, but it seems likely that HREPT data, along with its well-defined functional implications, will improve the clinical management of esophageal motility disorders.

Technical advances in monitoring human motility patterns

Abnormal motor patterns are implicated in many motility disorders. However, for many regions of the gut, our knowledge of normal and abnormal motility behaviors and mechanisms remains incomplete. There have been many recent advances in the development of techniques to increase our knowledge of gastrointestinal motility, some readily available while others remain confined to research centers. This review highlights a range of these recent developments and examines their potential to help diagnose and guide treatment for motility disorders.

Does body position modify the results of oesophageal high resolution manometry?

BACKGROUND Oesophageal motility classification using high resolution manometry (HRM) has been established in the supine position. Nevertheless, examination in the sitting position is more physiological. Our aim was to determine if body position modifies oesophago-gastric junction (OGJ) morphology and oesophageal motility. METHODS A total of 100 patients (47 males, mean age 51 years) were included in this study. The oesophageal HRM protocol included examination in supine and sitting positions. Recordings were reviewed by two different operators. Amplitude, duration, velocity, Distal Contractile Integral (DCI) and Pressurization Front Velocity of oesophageal waves induced by swallowing were recorded. KEY RESULTS The lower oesophageal sphincter resting pressure was not significantly changed by body position. The sitting position modified the OGJ classification in 12 patients. The inter-observer agreement to classify OGJ was moderate (kappa = 0.54 and 0.46, in the supine and sitting positions respectively) while it was good to diagnose motility disorders (kappa = 0.72 and 0.83). The percentage of normal waves was lower in the sitting position in comparison with the supine position (56%vs 67%, P < 0.01). The DCI was also lower in the sitting position (1125 mmHg.s.cm vs 1639, P < 0.01) as well as the amplitude of oesophageal waves. Finally the diagnosis was concordant in both positions in 72 patients. CONCLUSIONS & INFERENCES Body position can affect OGJ morphology and oesophageal motility assessment by HRM in some patients. Normal values in the sitting position should thus be determined. Inter-observer variation for the proposed classification of OGJ morphology must also be taken into account.

Evaluation of esophageal motor disorders in the era of high-resolution manometry and intraluminal impedance

The past few years were an exciting time in the study of esophageal motor disorders because new technologies emerged to study esophageal motor function and bolus transit. Although conventional manometry was long considered the "gold standard" for defining esophageal motor disorders, many technologic improvements occurred due to advances in transducer technology, computerization, and graphic data presentation. In addition, a relatively new technology, intraluminal impedance, was incorporated into manometric modalities. The most sophisticated systems now include combined high-resolution manometry with high-resolution impedance. Although these techniques provide more detailed information about esophageal function, whether they improve our ability to diagnose and treat patients more effectively is debatable. However, more recent data support that these advances actually improve our ability to diagnose and treat esophageal motor disorders. This article provides an update on these technologies in clinical practice and how they may be helpful in the future.

High-resolution manometry in clinical practice: utilizing pressure topography to classify oesophageal motility abnormalities

High-resolution manometry capable of pressure monitoring from the pharynx to the stomach together with pressure topography plotting represents an unquestionable evolution in oesophageal manometry. However, with this advanced technology come challenges and one of those is devising the optimal scheme to apply high-resolution oesophageal pressure topography (HROPT) to the clinical evaluation of patients. The first iteration of the Chicago classification was based on a systematic analysis of motility patterns in 75 control subjects and 400 consecutive patients. This review summarizes the analysis process as it has evolved. Individual swallows are analysed in a stepwise fashion for the morphology of the oesophagogastric junction (OGJ), the extent of OGJ relaxation, the propagation velocity of peristalsis, the vigour of the peristaltic contraction, and abnormalities of intrabolus pressure utilizing metrics that have now been customized to HROPT. These results are then synthesized into a comprehensive diagnosis that, although based on conventional manometry criteria, is also customized to HROPT measures. The resultant classification objectifies the identification of three unique subtypes of achalasia. Additionally, it provides enhanced detail in the description of distal oesophageal spasm, nutcracker oesophagus subtypes, and OGJ obstruction. It is our expectation that modification of this classification scheme will continue to occur and this should further clarify the utility of pressure topography plotting in assessing oesophageal motility disorders.