Influence of bolus consistency and position on esophageal high-resolution manometry findings

Integrated Relaxation Pressure and Its Diagnostic Ability May Vary According to the Conditions Used for HREM Recording

Integrated Residual Pressure (IRP) measured under conditions alternative to supine single swallows may provide clinically useful information regarding EGJ relaxation. This study aimed to compare IRP values obtained under different situations and explore their potential clinical utility. We analyzed and compared the values of IRP obtained from healthy volunteers and patients with suspected achalasia during supine single swallows (Ssup-IRP), sitting single swallows (Ssit-IRP), supine multiple rapid swallows (Msup-IRP), and sitting multiple rapid swallows (Msit-IRP). We analyzed the HREM recordings of 40 healthy volunteers and 53 patients with suspected achalasia. The four metrics were significantly different from each other in healthy volunteers (Ssup-IRP > Msup-IRP > Ssit-IRP > Msit-IRP) and their corresponding 95th percentiles were substantially distinct (Ssup-IRP: 25.3 mmHg, Ssit-IRP: 20.9 mmHg, Msup-IRP: 15.9 mmHg, and Msit-IRP: 11.9 mm Hg, respectively). Complete agreement among the four metrics in predicting abnormal IRP was found in 39 of the 47 patients with suspected achalasia who completed the protocol. Optimal cutoffs derived from ROC curve analysis demonstrated ≥ 0.95 specificities for detection of impaired EGJ relaxation among patients with suspected achalasia. Among the eight patients with suspected achalasia with normal Ssup-IRP, five demonstrated abnormal Msit-IRP and four abnormal Ssit-IRP. Significant differences of IRP exist depending on the measurement situation, indicating that correct interpretation of IRP values requires specific cutoffs for each situation.The sensitivities of Ssit-IRP and Msit-IRP in detecting defective EGJ relaxation appear to be slightly higher than that of Ssup-IRP.

Ethnic Differences in Clinical Presentations and Esophageal High-Resolution Manometry Findings in Patients with Achalasia

BACKGROUND

Ethnic differences in achalasia presentations have scarcely been described. The association between achalasia and immunologic HLA haplotypes suggests that there may be a genetic predisposition. We aimed to evaluate differences in demographic, clinical, endoscopic, and manometric findings between two distinct ethnic groups with achalasia-Israeli Arabs (IA) and Israeli Jews (IJ).

METHODS

A retrospective study was performed at two medical centers. High-resolution manometry (HRM) reports were reviewed for newly-diagnosed achalasia patients. Demographic data, clinical presentations, endoscopy reports, and HRM metrics including the integrated relaxation pressure (IRP) were all reviewed.

RESULTS

Overall, 94 achalasia patients were included (53.2% male; mean age 54.5 ± 18.0). 43 patients were IA (45.7%). Body mass index (BMI) was similar in both groups. Compared to IJ, the IA patients had more esophageal dysphagia (100% vs. 88.2%; P = 0.022), chest pain (46.5% vs. 25.5%; P = 0.033), and a tortuous esophagus on endoscopy (23.3% vs. 3.9%; p = 0.005). IA patients were also diagnosed at a younger age than IJ patients (50.9 ± 17.5 vs. 57.5 ± 18.0; p = 0.039). Furthermore, IRP values were higher among IA patients than IJ patients (32.2 ± 13.8 vs. 23.3 ± 8.4; p < 0.001). A regression model analysis found that ethnicity significantly predicted IRP (β = - 10, p < .001).

CONCLUSION

Ethnicity appears to affect achalasia clinical presentation and HRM findings. IA achalasia patients are diagnosed at a younger age, present with more severe esophageal symptoms, and have a higher IRP compared to IJ patients. Additional studies of diverse, multiethnic populations, especially with genetic evaluations, are required to further assess the role of ethnicity in achalasia.

Impact of patient position on esophageal motility disorders using high-resolution esophageal manometry with impedance (HREMI): supine versus upright swallows

BACKGROUND

High-resolution esophageal manometry with impedance (HREMI) performed with supine patient positioning is used to evaluate patients for esophageal dysmotility. However, most patients experience symptoms related to esophageal dysmotility when eating or drinking upright. The aims of this study are to: (1) compare HREMI metrics in supine versus upright position; and (2) determine if upright position alters motility characterization of patients.

METHODS

HREMI of twelve wet swallows in supine position and five wet swallows in upright position were performed on normal subjects (NS) and consecutive patients. Chicago Classification v3.0 (CC) diagnoses were evaluated in the supine position and a modified version of the Chicago Classification system was used in the upright position using normative upright values for DCI and IRP.

RESULTS

DCI decreased in NS by 414 mmHg × cm × sec (p = 0.001) and patients by 613 mmHg × cm × sec (p < 0.001). IRP decreased in NS by 6.2 mmHg (p < 0.001) and patients by 4.6 mmHg (p < 0.001). The rate of successful bolus clearance decreased in the upright position in patients by 11% (p < 0.001), but no statistically significant differences were observed in NS. 82 of 200 patients (41%) had a change in CC diagnosis in the upright position. Bolus clearance in the upright position varied in patients depending on their diagnosis in the upright position.

CONCLUSIONS

Upright swallows had lower LES, IRP, DCI and UES pressures in both normal subjects and patients with decreased bolus clearance in patients. Upright positioning can alter esophageal motility patterns and enhance diagnostic yield. Thus, upright swallows supplement supine swallows to help characterize esophageal dysmotility.

The effects of different postures and provocative swallow materials on the normative Chicago 3.0 metrics in a healthy Asian population

BACKGROUND AND AIM

Variations in the Chicago 3.0 normative metrics may exist with different postures and with different provocative swallow materials in a healthy Asian population.

METHOD

Eligible healthy Malay volunteers were invited to undergo the high-resolution esophageal manometry (inSIGHT Ultima, Diversatek Healthcare, Milwaukee, WI, USA). In recumbent and standing positions, test swallows were performed using liquid, viscous, and solid materials. Metrics including integrated relaxation pressure 4 s (IRP-4 s, mmHg), distal contractile integral (DCI, mmHg s cm), distal latency (DL, s), and peristaltic break (PB, cm) were reported in median and 95th percentile.

RESULTS

Fifty of 57 screened participants were recruited, and 586 saline, 265 viscous, and 261 solid swallows were analyzed. Per-patient wise, in the recumbent position, 95th percentile for IRP-4 s, DCI, DL, and PB were 16.5 mmHg, 2431 mmHg s cm, 8.5 s, and 7.2 cm, respectively. We observed that with each posture, the use of viscous swallows led to changes in DL, but the use of solid swallows led to more changes in the metrics including DCI and length of PB. Compared with a recumbent posture, anupright posture led to lower IRP-4 s and DCI values. Both per-patient analysis and per-swallow analyses yielded almost similar results when comparing the different postures and types of swallows. No major motility disorders were observed in this cohort of asymptomatic population. However, more motility disorders were reported in the upright position.

CONCLUSIONS

Variations in metrics can be observed in different postures and with different provocative swallow materials in a healthy population. The normative Chicago 3.0 metrics are also determined for the Malay population.

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.

Normative reference values for esophageal high-resolution manometry in healthy adults: A systematic review

Establishing normative values of high-resolution esophageal manometry is necessary for accurate interpretation and comparison of measurements. In this systematic review, we aimed to summarize normal values for different esophageal high-resolution manometry systems. Moreover, we assessed the effect of body position, bolus consistency, and provocative maneuvers on these normative thresholds. We searched Medline, Embase, and the Cochrane Library from January 1st, 2006, to January 20th, 2020, for studies that reported normative data of high-resolution manometry in healthy volunteers. We assessed methodological quality of the included studies and planned a descriptive analysis. We analyzed data from 54 articles describing normative thresholds in high-resolution manometry using solid-state or water-perfused systems. Forty-six studies performed the manometry study in the supine position with liquid swallows, whereas sixteen studies described normative values in the upright position. Twelve studies assessed normative values for different bolus consistencies, and nine studies evaluated different provocative maneuvers. There is a considerable variety of normative values for esophageal high-resolution manometry depending on the equipment used and the protocols performed to obtain measurements. This should be taken into account when evaluating measurements in clinical practice and when comparing results of published research studies.

Updates on diagnostic modalities for esophageal dysphagia

Esophageal dysphagia is a common symptom in adults. Fluoroscopic contrast studies, endoscopy, and esophageal manometry have been used in the diagnosis of esophageal dysphagia for many years. The diagnostic yield has been improved with new test protocols that highlight abnormal bolus transit in the esophagus and outflow obstruction, as well as new high-definition and high-resolution technical advances in equipment. Functional luminal impedance planimetry and the addition of impedance to high-resolution esophageal manometry have also allowed the assessment of new parameters to better understand esophageal structure and function. In this concise review, we describe the role and utility of various diagnostic modalities in the assessment of patients with esophageal dysphagia.

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.

Effect of Body Position on High-resolution Esophageal Manometry Variables and Final Manometric Diagnosis

Background/Aims

According to the Chicago classification version 3.0, high-resolution manometry (HRM) should be performed in the supine position. However, with the patient in the upright/sitting position, the test could more closely simulate real-life behavior and may be better tolerated. We performed a systematic review of the literature to search whether the manometric variables and the final diagnosis are affected by positional changes.

Methods

A literature search was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Studies published in English that compared HRM results in different body positions were included. Moreover, the change in diagnosis of esophageal motility disorders according to the shift of body position was investigated.

Results

Seventeen studies including 1714 patients and healthy volunteers met the inclusion criteria. Six studies showed a significant increase in lower esophageal sphincter basal pressure in the supine position. Integrated relaxation pressure was significantly higher in the supine position in 10 of 13 studies. Distal contractile index was higher in the supine position in 9 out of 10 studies. One hundred and fifty-one patients (16.4%) out of 922 with normal HRM in the supine position were diagnosed with ineffective esophageal motility (IEM) when the test was performed in the upright position (P < 0.001).

Conclusions

Performing HRM in the upright position affects some variables and may change the final manometric diagnosis. Further studies to determine the normal values in the sitting position are needed.

Normative Values for Esophageal Motility Assessed in the Physiological Seated Position for 16-Channel Water Perfused High-resolution Esophageal Manometry System and Postural Variations in Healthy Volunteers

Background/Aims

Consensus guidelines for performance and analysis of high-resolution esophageal manometry (HREM) recommend use of equipment, population and posture specific normative values. To provide normative values for Chicago classification (CC) metrics in the physiological seated position for a 16-channel water perfused system (Dentsleeve HREM catheter, Advanced Manometry Systems, Melbourne, Australia) widely used in India and other countries with limited access to solid-state equipment. The results are compared with published CC metrics in supine position done using the same system and volunteers.

Methods

HREM tracings of ten 5 mL water swallows in sitting posture were acquired in healthy volunteers and normative values for CC version 3.0 metrics calculated. Individual swallows were paired with previously reported supine swallows for postural variations (Wilcoxon sign rank test) and concordance of CC diagnoses (Pearson coefficient).

Results

Analysis of 530 sitting posture water swallows (53 subjects) and comparison with their supine data revealed significantly higher integrated relaxation pressure (IRP; median 6.7 mmHg vs 6.1 mmHg) but lower distal latency (DL; mean 6.3 seconds vs 6.8 seconds) and distal contractile integral (DCI; mean 1224 mmHg sec cm vs 1456 mmHg sec cm). Sitting posture normal was defined as: IRP < 13.9, DL > 4.5, and DCI = 115–4500 (absent contractility: DCI < 30). CC diagnoses concordance using posture-specific cut-offs was moderate (k = 0.47).

Conclusions

This paper provides normative values for the Advanced Manometry Systems 16-channel water perfused system in the physiological seated position for CC metrics. Our findings of higher IRP and lower DCI in sitting posture than previously reported supine CC cut-offs, confirm the need to use posture-specific cut-offs for reporting HREM tracings.

Ineffective esophageal motility: Concepts, future directions, and conclusions from the Stanford 2018 symposium

BACKGROUND

Ineffective esophageal motility (IEM) is a heterogenous minor motility disorder diagnosed when ≥50% ineffective peristaltic sequences (distal contractile integral <450 mm Hg cm s) coexist with normal lower esophageal sphincter relaxation (integrated relaxation pressure < upper limit of normal) on esophageal high-resolution manometry (HRM). Ineffective esophageal motility is not consistently related to disease states or symptoms and may be seen in asymptomatic healthy individuals.

PURPOSE

A 1-day symposium of esophageal experts reviewed existing literature on IEM, and this review represents the conclusions from the symposium. Severe IEM (>70% ineffective sequences) is associated with higher esophageal reflux burden, particularly while supine, but milder variants do not progress over time or consistently impact quality of life. Ineffective esophageal motility can be further characterized using provocative maneuvers during HRM, especially multiple rapid swallows, where augmentation of smooth muscle contraction defines contraction reserve. The presence of contraction reserve may predict better prognosis, lesser reflux burden and confidence in a standard fundoplication for surgical management of reflux. Other provocative maneuvers (solid swallows, standardized test meal, rapid drink challenge) are useful to characterize bolus transit in IEM. No effective pharmacotherapy exists, and current managements target symptoms and concurrent reflux. Novel testing modalities (baseline and mucosal impedance, functional lumen imaging probe) show promise in elucidating pathophysiology and stratifying IEM phenotypes. Specific prokinetic agents targeting esophageal smooth muscle need to be developed for precision management.

Effects of Posture and Swallow Volume on Esophageal Motility Morphology and Probability of Bolus Clearance: A Study Using High-Resolution Impedance Manometry

The Chicago classification diagnostic criteria of esophageal motility disorders are based on 5-ml water swallows in the supine position and have not been analyzed for the correlation between the morphology and bolus transit in the upright position and larger volume swallow conditions. This study aimed to evaluate the effect of posture and swallow volume on peristaltic morphology and the probability of bolus clearance in patients with nonspecific esophageal disorder. A total of 139 patients (4,214 swallows) were included for high-resolution impedance manometry analysis in the right lateral recumbent and upright positions, as well as 5- and 10-ml liquid swallows. Intact peristalses were more frequent in the right lateral recumbent position than in the upright position. No difference was reported on failed peristalsis between both positions. Breaks were more frequent in the upright position. A 20 mmHg isobaric contour (compared with 30 mmHg) was associated with decreased bolus clearance. Bolus clearance probability with 10-ml swallows is greater than that with 5-ml swallows. There was no significant difference in the total bolus clearance comparing between the right lateral recumbent and upright positions. The right lateral recumbent position was associated with a higher intact peristalsis. The volume of swallow did not affect the integrality of esophageal peristalsis but did improve the bolus clearance.

The differences in the esophageal motility between liquid and solid bolus swallows: A multicenter high-resolution manometry study in Chinese asymptomatic volunteers

BACKGROUND

The results of the esophageal body motility differences between liquid and solid swallows from high-resolution manometry (HRM) studies are not consistent. The information of the frequency of ineffective liquid and solid bolus swallows in healthy individuals during HRM procedure is limited. The normative values of the HRM parameters of both liquid and solid swallows for Chinese population are lacking.

METHODS

The esophageal HRM data of 101 healthy volunteers from multicenters in China were analyzed. The values of the HRM parameters were summarized and compared between liquid and solid swallows. The frequencies of ineffective liquid and solid swallows were summarized.

RESULTS

Esophagus contracted stronger and slower in solid bolus swallows than water swallows with HREM. Ineffective water swallow (DCI < 450 mm Hg.s.cm) and ineffective bread swallow (DCI < 800 mm Hg.s.cm) were frequently seen in asymptomatic individuals. The adding of bread swallows to the HREM procedure might cause diagnostic change in about 15.8% (16/101) of the asymptomatic individuals.

CONCLUSIONS

The vigor and velocity of the esophageal peristalsis between liquid and solid bolus swallows are different. Ineffective water and solid bolus swallows are not rare. Adding solid bolus swallows brings diagnostic change, and it may be needed routinely for the HRM procedure.

Evaluation of Esophageal Contraction Reserve Using HRM in Symptomatic Esophageal Disease

Esophageal high resolution manometry (HRM) is the gold standard for assessment of esophageal motor disorders, but motor responses to the standard 5 mL water swallow protocol may not provide precision in defining minor motor disorders. Provocative maneuvers, particularly multiple rapid swallows (MRS), have been used to assess deglutitive inhibition during the repetitive swallows, and the contractile response following the final swallow of the sequence. The augmentation of esophageal smooth muscle contraction following MRS is termed contraction reserve. This is determined as the ratio between esophageal body contraction vigor (distal contractile integral, DCI) following MRS to the mean DCI after single swallows, which is ≥1 in the presence of contraction reserve. Reliable assessment of contraction reserve requires the performance of 3 MRS maneuvers during HRM. Absence of contraction reserve is associated with a higher likelihood of late postfundoplication dysphagia and may correlate with higher esophageal reflux burden on ambulatory reflux monitoring. Esophageal motor responses to abdominal compression, functional lumen imaging probe (FLIP) balloon distension, and pharmacologic testing (using edrophonium and cisapride) may correlate with contraction reserve. Other provocative tests useful during HRM include rapid drink challenge, solid and viscous swallows, and standardized test meals, which are more useful in evaluation of esophageal outflow obstruction and dysphagia syndromes than in identification of contraction reserve. Provocative maneuvers have been recommended as part of routine HRM protocols, and while useful clinical information can be gleaned from these maneuvers, further research is necessary to determine the precise role of provocative testing in clinical esophagology.

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.

Utility of Esophageal High-Resolution Manometry in Clinical Practice: First, Do HRM

Esophageal high-resolution manometry (HRM) has advanced the understanding of esophageal motor function and the ability to diagnose and manage disorders of esophageal motility. In this review, we describe the indications for and the technical performance of HRM. The Chicago classification of esophageal motor function, now in its third iteration, streamlines and standardizes the nomenclature and basic interpretation of HRM data depicted as Clouse topographic plots. In clinical practice, HRM is an important diagnostic test for patients with dysphagia as well as patients with suspected gastroesophageal reflux disease (GERD), particularly in those patients with a suboptimal symptomatic response to antisecretory therapy. HRM can support diagnoses such as achalasia, as well as provide evidence for behavioral disorders such as rumination syndrome or supragastric belching with the assistance of postprandial HRM with impedance. Further, the GERD classification of motor function introduces a three-part hierarchical evaluation of esophageal motor function in GERD, highlighting the value of assessment of esophageal contractile reserve through provocative maneuvers during HRM such as multiple rapid swallows.

Improving High-resolution Impedance Manometry Using Novel Viscous and Super-viscous Substrates in the Supine and Upright Positions: A Pilot Study

Background/Aims

Swallows with viscous or solid boluses in different body positions alter esophageal manometry patterns. Limitations of previous studies include lack of standardized viscous substrates and the need for chewing prior to swallowing solid boluses. We hypothesize that high-resolution impedance manometry (HRiM) using standardized viscous and super-viscous swallows in supine and upright positions improves sensitivity for detecting esophageal motility abnormalities when compared with traditional saline swallows. To establish normative values for these novel substrates, we recruited healthy volunteers and performed HRiM.

Methods

Standardized viscous and super-viscous substrates were prepared using “Thick-It” food thickener and a rotational viscometer. All swallows were administered in 5-mL increments in both supine and upright positions. HRiM metrics and impedance (bolus transit) were calculated. We used a paired two-tailed t test to compare all metrics by position and substrate.

Results

The 5-g, 7-g, and 10-g substrates measured 5000, 36 200, and 64 700 mPa sec, respectively. In 18 volunteers, we observed that the integrated relaxation pressure was lower when upright than when supine for all substrates (P < 0.01). The 10-g substrate significantly increased integrated relaxation pressure when compared to saline in the supine position (P < 0.01). Substrates and positions also affected distal contractile integral, distal latency, and impedance values.

Conclusions

We examined HRiM values using novel standardized viscous and super-viscous substrates in healthy subjects for both supine and upright positions. We found that viscosity and position affected HRiM Chicago metrics and have potential to increase the sensitivity of esophageal manometry.

Physiological augmentation of esophageal distension pressure and peristalsis during conditions of increased esophageal emptying resistance

BACKGROUND

Abdominal compression has been implemented as a provocative maneuver in high-resolution impedance manometry (HRIM) to "challenge" normal esophageal physiology with the aim of revealing abnormal motor patterns which may explain symptoms. In this study, we measured the effects of abdominal compression on esophageal functioning utilizing novel pressure-impedance parameters and attempted to identify differences between healthy controls and globus patients.

METHODS

Twenty-two healthy volunteers (aged 23-32 years, 41% female) and 22 globus patients (aged 23-72 years, 68% female) were evaluated with HRIM using a 3.2-mm water perfused manometric and impedance catheter. All participants received 10 × 5 mL liquid swallows; healthy controls also received 10 × 5 mL liquid swallows with abdominal compression created using an inflatable cuff. All swallows were analyzed to assess esophageal pressure topography (EPT) and pressure-flow metrics, indicative of distension pressure, flow timing and bolus clearance were derived.

KEY RESULTS

The effect of abdominal compression was shown as a greater contractile vigor of the distal esophagus by EPT and higher distension pressure based on pressure-flow metrics. Age and body mass index also increased contractile vigor and distension pressure. Globus patients were similar to controls.

CONCLUSIONS AND INTERFERENCES

Intrabolus pressure and contractile vigor are indicative of the physiological modulation of bolus transport mechanisms. Provocative testing by abdominal compression induces changes in these esophageal bolus dynamics.

Esophageal provocation tests: Are they useful to improve diagnostic yield of high resolution manometry?

High resolution manometry (HRM) is the gold standard to diagnose esophageal motility disorders but has some limitations. The inclusion of provocative tests might enhance the diagnostic yield of HRM. These tests are easy to perform and to add to the regular manometry protocol. Multiple rapid swallows (MRS; 5 2-mL swallows) is useful to assess the contractile reserve and deglutitive inhibition. The optimal number of MRS to perform might be 3 as suggested by Mauro et al. in this issue of Neurogastroenterology & Motility. The absence of contractile reserve might be associated with gastro-esophageal reflux disease and with an increased risk of post fundoplication dysphagia. Single viscous and solid swallows might enhance the detection of esophageal motility disorders but are not significantly associated with symptom occurrence. Test meal has the advantage to represent a real-life scenario and is promising to depict significant motility findings responsible for esophageal symptoms. Post-prandial recording might also be of interest to diagnose rumination and belching disorders. The best indication of rapid drink challenge test (free drinking of 200 mL) is currently the diagnosis of esophago-gastric junction obstruction. Finally, abdominal compression might be an option to evaluate response of esophageal peristalsis in a context of outflow resistance as proposed by Brink et al. in this issue. These provocative maneuvers appear to provide a complementary role in the evaluation of esophageal motility but require prospective studies to determine the validity of the findings and whether they will lead to changes in clinical practice.

Normal Values of High-Resolution Manometry in Supine and Upright Positions in a Thai Population

BACKGROUND

Although cut-off values used in high-resolution manometry (HRM) to diagnose esophageal motility disorders are based on representative samples of the US population and assume a supine position, differences in population and body positioning can reportedly affect results.

AIMS

To establish normal HRM values for Thai people in both supine and upright positions.

METHODS

Forty-one healthy subjects were recruited, each of whom underwent solid-state HRM with ten 5-mL swallows of water in both the supine and upright positions. Measuring parameters according to the Chicago classification criteria (CC v3.0) were included, for which the mean, median and 5th and 95th percentiles (PCTLs) were calculated.

RESULTS

The results corresponded with the CC v3.0 criteria, except for the mean, and 5th PCTL of the distal contractile integral (DCI), which were lower for this population. In the upright position, the mean and median values for DCI, intrabolus pressure and integrated relaxation pressure were significantly decreased, whereas the length of the transitional zone was significantly increased. The limitations of this study include: (1) the relatively low number of participants, (2) the limited recruitment of participants only at Ramathibodi Hospital and (3) the limited recruitment of only young and middle-aged participants.

CONCLUSIONS

We established normal values for the HRM parameters in a representative sample of the Thai population. Our supine results still prove that the use of the CC v3.0 is preferable. HRM testing in patients measured in the upright position should be analyzed based on the normative values obtained from upright swallow studies.

Diagnostic yield of high-resolution manometry with a solid test meal for clinically relevant, symptomatic oesophageal motility disorders: serial diagnostic study

BACKGROUND

The use of high-resolution manometry (HRM) to diagnose oesophageal motility disorders is based on ten single water swallows (SWS); however, this approach might not be representative of oesophageal function during the ingestion of normal food. We tested whether inclusion of a standardised solid test meal (STM) to HRM studies increases test sensitivity for major motility disorders. Additionally, we assessed the frequency and cause of patient symptoms during STM.

METHODS

Consecutive patients who were referred for investigation of oesophageal symptoms were recruited at Nottingham University Hospitals (Nottingham, UK) in the development study and at University Hospital Zürich (Zürich, Switzerland) in the validation study. HRM was done in the upright, seated position with a solid-state assembly. During HRM, patients ingested ten SWS, followed by a standardised 200 g STM. Diagnosis of oesophageal motility disorders was based on the Chicago Classification validated for SWS (CCv3) and with STM (CC-S), respectively. These studies are registered with ClinicalTrials.gov, numbers NCT02407938 and NCT02397616.

FINDINGS

The development cohort included 750 patients of whom 360 (48%) had dysphagia and 390 (52%) had reflux or other symptoms. The validation cohort consisted of 221 patients, including 98 (44%) with dysphagia and 123 (56%) with reflux symptoms. More patients were diagnosed with a major motility disorder by use of an STM than with SWS in the development set (321 [43%] patients diagnosed via STM vs 163 [22%] via SWS; p<0·0001) and validation set (73 [33%] vs 49 [22%]; p=0·014). The increase was most evident in patients with dysphagia (241 [67%] of 360 patients on STM vs 125 [35%] patients on SWS in the development set, p<0·0001), but was also present in those referred with reflux symptoms (64 [19%] of 329 patients vs 32 [10%] patients in the development set, p=0·00060). Reproduction of symptoms was reported by nine (1%) of 750 patients during SWS and 461 (61%) during STM (p<0·0001). 265 (83%) of 321 patients with major motility disorders and 107 (70%) of 152 patients with minor motility disorders reported symptoms during the STM (p=0·0038), compared with 89 (32%) of 277 patients with normal motility as defined with CC-S (p<0·0001).

INTERPRETATION

The diagnostic sensitivity of HRM for major motility disorders is increased with use of the STM compared with SWS, especially in patients with dysphagia. Observations made during STM can establish motility disorders as the cause of oesophageal symptoms.

FUNDING

None.

Characterization of Esophageal Motility Disorders in Children Presenting With Dysphagia Using High-Resolution Manometry

PURPOSE OF REVIEW

The Chicago classification was based on metrics derived from studies in asymptomatic adult subjects. Our objectives were to characterize esophageal motility disorders in children and to determine whether the spectrum of manometric findings is similar between the pediatric and adult populations.

RECENT FINDINGS

Studies have suggested that the metrics utilized in manometric diagnosis depend on age, size, and manometric assembly. This would imply that a different set of metrics should be used for the pediatric population. There are no standardized and generally accepted metrics for use in the pediatric population, though there have been attempts to establish metrics specific to this population. Overall, we found that the distribution of esophageal motility disorders in children was like that described in adults using the Chicago classification. This analysis will serve as a prequel to follow-up studies exploring the individual metrics for variability among patients, with the objective of establishing novel metrics for the pediatric population.

ESOPHAGEAL MOTILITY IN MEN AND WOMEN EVALUATED BY HIGH-RESOLUTION MANOMETRY

BACKGROUND

Esophageal motility has been described in the literature as having differences between men and women. Most of these investigations use the water perfusion method for esophageal manometry. In this investigation the esophageal motility of men and women was compared with high-resolution manometry of the esophagus.

OBJECTIVE

To compare the esophageal motility of men and women with the high-resolution manometry method for esophageal manometry, performed in the sitting position. The hypothesis was that men and women have differences in esophageal motility.

METHODS

High-resolution manometry was performed in normal volunteers, 10 men [mean age: 37.5 (8.1) years] and 12 women [mean age: 38.7 (7.5) years], in the sitting position and with 10 swallows of a 5 mL bolus of saline, with an interval of at least 30 seconds between consecutive swallows. We evaluated the integrated relaxation pressure of the lower esophageal sphincter, contraction front velocity, distal contraction integral, distal latency, proximal contraction extension, proximal contraction duration >30 mmHg, proximal contraction duration, proximal contraction integral and maximal upper esophageal sphincter pressure.

RESULTS

There was no significant difference between men and women in the variables measured.

CONCLUSION

There was no difference in esophageal motility of men and women evaluated by the high resolution manometry method, in the sitting position with swallows of a liquid bolus.

Esophageal motility after peroral endoscopic myotomy for achalasia

BACKGROUND

Peroral endoscopic myotomy (POEM) has been introduced as a novel endoscopic treatment for achalasia. The aim of this work is to assess the changes in esophageal motility caused by POEM in patients with achalasia.

METHODS

Forty-one patients with achalasia underwent POEM from September 2012 to November 2014. Esophageal motility of all patients was evaluated preoperatively and 1 month after POEM utilizing high-resolution manometry, which was performed with ten water swallows, ten steamed bread swallows, and multiple rapid swallows (MRS).

RESULTS

In single swallows, including liquid swallows and bread swallows, all the parameters of lower esophagus sphincter resting pressure (LESP), 4-s integrated relaxation pressure (4sIRP), and intra-bolus pressure (IBP) were decreased between pre- and post-POEM patients (all p < 0.05). Postoperatively, the trend of distal contractile integral (DCI) and distal esophageal peristaltic amplitude declined in subtype II and subtype III (subtype II: p < 0.05; subtype III: p > 0.05), but increased in subtype I (subtype I: p > 0.05). In liquid swallows, the Eckardt score of subtype II patients decreased with DCI, and distal esophageal peristaltic amplitude after POEM was significantly lower compared with those showing increased values of those two parameters (p < 0.05). In MRS, the rate of LES relaxation increased from 66.67 to 95.24%, but without normal response in all achalasia patients.

CONCLUSIONS

POEM reduces LES pressure in achalasia, and partly restores esophageal motility. POEM displayed varying effect on esophageal motility in patients with different patterns of swallowing. In addition, the changes in parameters associated with esophageal peristalsis correlated with decreases in Eckardt score.

Normal esophageal high-resolution manometry and impedance values in the supine and sitting positions in the population of Northern China

The aim of this study was to investigate the normal high-resolution manometry and impedance (HRiM) values in the supine and sitting positions in the population of Northern China, and to investigate the influence of different body positions and bolus consistency on esophageal HRiM findings. In this study, healthy volunteers in the supine position underwent esophageal HRiM examination of 10 swallows of 5 mL normal saline solution and 10 swallows of 5 mL synthetic gel of known viscosity, and in the sitting position of an additional five swallows of a synthetic gel of known viscosity. Total bolus transit time (TBTT), complete bolus transit rate (CBTR), distal contractile integral (DCI), distal esophageal amplitude (DEA), and integrated relaxation pressure (IRP) were measured. Sixty-two healthy volunteers were examined in the supine position and 45 of these performed additional swallows of the viscous gel in the sitting position. In the supine position, normal values for swallowing the liquid and viscous boli were as follows: TBTT 6.9 ± 0.9 and 8.0 ± 1.2 s (P < 0.001), CBTR 90.3 ± 14.0 and 77.9 ± 20.3% (P < 0.001), DCI 1891.5 ± 1131.9 and 1967.8 ± 1140.1 mmHg.s.cm (P = 0.227), DEA 95.3 ± 35.4 and 98.7 ± 37.5 mmHg (P = 0.148), and IRP 10.4 ± 4.9 and 9.0 ± 4.2 mmHg (P < 0.001), respectively. For swallows of the viscous boli in the sitting position, TBTT, DCI, DEA, and IRP were significantly decreased, while CBTR was unchanged (P = 0.075). Normal HRiM values of the population of Northern China were established. Esophageal transit times of viscous boli were significantly slower, more often incomplete and produced less normal peristalsis in the supine position than swallows of liquid boli. Independent reference values for different manometric systems, body positions, and population need to be established before clinical application.

How the Body Position Can Influence High-resolution Manometry Results in the Study of Esophageal Dysphagia and Gastroesophageal Reflux Disease

BACKGROUND/AIMS

The body position can influence esophageal motility data obtained with high-resolution manometry (HRM). To examine whether the body position influences HRM diagnoses in patients with esophageal dysphagia and gastroesophageal reflux disease (GERD).

METHODS

HRM (Manoscan) was performed in 99 patients in the sitting and supine positions; 49 had dysphagia and 50 had GERD as-sessed by 24-hour pH monitoring. HRM plots were analyzed according to the Chicago classification.

RESULTS

HRM results varied in the final diagnoses of the esophageal body (EB) in patients with dysphagia (P = 0.024), the result being more distal spasm and weak peristalsis while sitting. In patients with GERD, the HRM diagnoses of the lower esophageal sphinc-ter (LES), the esophagogastric junction (EGJ) morphology, and EB varied depending on the position; (P = 0.063, P = 0.017, P = 0.041 respectively). Hypotensive LES, EGJ type III (hiatal hernia), and weak peristalsis were more frequently identified in the sitting position. The reliability (kappa) of the position influencing HRM diagnoses was similar in dysphagia and GERD ("LES diagnosis": dysphagia 0.32 [0.14-0.49] and GERD 0.31 [0.10-0.52], P = 0.960; "EB diagnosis": dysphagia 0.49 [0.30-0.69] and GERD 0.39 [0.20-0.59], P = 0.480). The reliability in "EGJ morphology" studies was higher in dysphagia 0.81 (0.68-0.94) than in GERD 0.55 (0.37-0.73), P = 0.020.

CONCLUSIONS

HRM results varied according to the position in patients with dysphagia and GERD. Weak peristalsis was more frequently diagnosed while sitting in dysphagia and GERD. Hypotensive LES and EGJ type III (hiatal hernia) were also more frequently diagnosed in the sitting position in patients with GERD.

The effect of position on esophageal structure and function determined with solid-state high-resolution manometry

OBJECTIVE

To investigate the influence of posture on the anatomy and function of esophageal sphincters using solid-state high-resolution manometry.

METHODS

Fifty individuals underwent esophageal manometry with a 36-channel solid-state catheter in the supine and upright positions. The length and pressure of the esophageal sphincters, as well as the esophageal and intra-abdominal lengths of lower esophageal sphincter (LES), were recorded. The residual pressure of the upper esophageal sphincter (UES) and the 4-s integrated relaxation pressure were also measured when the participants swallowed 10 consecutive servings of water (5 mL each). The Bland-Altman plot was used to assess agreement between these parameters in the supine and upright positions.

RESULTS

The LES resting pressure was significantly decreased in the upright position compared with the supine position (13.85 ± 5.90 mmHg vs 18.09 ± 7.80 mmHg, P = 0.000). Weaker integrated relaxation pressures were observed when the participants were in the upright position (5.66 ± 3.33 mmHg vs 7.80 ± 3.25 mmHg, P = 0.000). Compared with the supine position, the upright esophageal length was longer (P = 0.004) and the upper border of the LES was lower (P = 0.050) when the individuals were in the upright position. The agreement between the two positions was acceptable for the esophageal length, LES upper border location and LES pressure measurements.

CONCLUSIONS

Body position exerts a greater influence on the LES than on the UES. Thus, it is necessary to establish normal values for the LES basal pressure and residual pressure in different positions.

Randomized controlled trial of transoral incisionless fundoplication vs. proton pump inhibitors for treatment of gastroesophageal reflux disease

OBJECTIVES

Transoral incisionless fundoplication (TIF) was developed in an attempt to create a minimally invasive endoscopic procedure that mimics antireflux surgery. The objective of this trial was to evaluate effectiveness of TIF compared with proton pump inhibition in a population consisting of gastroesophageal reflux disease (GERD) patients controlled with proton pump inhibitors (PPIs) who opted for an endoscopic intervention over lifelong drug dependence.

METHODS

Patients with chronic GERD were randomized (2:1) for TIF or continuation of PPI therapy. American Society of Anesthesiologists >2, body mass index >35 kg/m(2), hiatal hernia >2 cm, and esophageal motility disorders were exclusion criteria. Primary outcome measure was GERD-related quality of life. Secondary outcome measures were esophageal acid exposure, number of reflux episodes, PPI usage, appearance of the gastroesophageal valve, and healing of reflux esophagitis. Crossover for the PPI group was allowed after 6 months.

RESULTS

A total of 60 patients (TIF n=40, PPI n=20, mean body mass index 26 kg/m(2), 37 male) were included. At 6 months, GERD symptoms were more improved in the TIF group compared with the PPI group (P<0.001), with a similar improvement of distal esophageal acid exposure (P=0.228) compared with baseline. The pH normalization for TIF group and PPI group was 50% and 63%, respectively. All patients allocated for PPI treatment opted for crossover. At 12 months, quality of life remained improved after TIF compared with baseline (P<0.05), but no improvement in esophageal acid exposure compared with baseline was found (P=0.171) and normalization of pH was accomplished in only 29% in conjunction with deteriorated valve appearances at endoscopy and resumption of PPIs in 61%.

CONCLUSION

Although TIF resulted in an improved GERD-related quality of life and produced a short-term improvement of the antireflux barrier in a selected group of GERD patients, no long-term objective reflux control was achieved.

Influence of everyday bolus consistencies in different body positions on high-resolution esophageal pressure topography (HREPT) parameters

The standard protocol for esophageal manometry involves placing the patient in the supine position with head turned to left (supine head left [SHL]) while evaluating liquid bolus swallows. Routinely, semisolid or solid boluses are not evaluated. Currently, the daily American diet includes up to 40% solid or semisolid texture. Thus far, the data on the effect of different bolus on high-resolution esophageal pressure topography (HREPT) parameters are scarce. This study aims to evaluate the effect of every day bolus consistencies in different body positions on HREPT variables. HREPT was performed on healthy volunteers with a modified protocol including liquid swallows in the SHL position followed by applesauce (semisolid), cracker (solid), and marshmallow (soft solid) in three different positions (SHL, sitting, and standing). A total of 38 healthy adult subjects (22 males and 16 females, median age = 27, and mean body mass index = 25) were evaluated. The resting upper esophageal sphincter pressure was significantly different while subjects swallowed crackers, applesauce, and marshmallows in most positions compared with liquid SHL (P < 0.05). The lower esophageal sphincter, contractile front velocity, and distal contractile integral pressures did not differ in all different consistencies compared with SHL. The integrated relaxation period was significantly higher with solid bolus compared with liquid bolus only in SHL position. The intrabolus pressure was significantly different with solid and soft solid boluses in all postures compared to liquid SHL. The American diet consistency affects upper esophageal sphincter pressure and partially integrated relaxation period and intrabolus pressure in various positions. Semisolid bolus swallows do not cause substantial pressure changes and are safe for evaluation and maintaining adequate caloric intake in patients with dysphagia who cannot tolerate solids.

Normative values in esophageal high-resolution manometry

BACKGROUND

Esophageal high-resolution manometry (HRM) has rapidly gained much popularity worldwide. The Chicago Classification for esophageal motility disorders is based on a set of normative values for key metrics that was obtained using one of the commercially available HRM systems. Thus, it is of great importance to evaluate whether these normative values can be used for other HRM systems as well.

PURPOSE

In this review, we describe the presently available HRM systems, the currently known normative thresholds and the factors that influence them, and assess the use of these thresholds. Numerous factors including the type of HRM system, demographic factors, catheter diameter, body position during testing, consistency of bolus swallows, and esophageal length have an influence on the normative data. It would thus be ideal to have different sets of normal values for each of these factors, yet at the moment the amount of normative data is limited. We suggest broadening the normal range for parameters, as this would allow abnormal values to be of more significance. In addition, we suggest conducting studies to assess the physiological relevance of abnormal values and stress that for each system different normative thresholds may apply.

Impedance as an adjunct to manometric testing to investigate symptoms of dysphagia: What it has failed to do and what it may tell us in the future

Dysphagia is a common reason for referral for investigations of oesophageal motility. Impedance measurement has now been incorporated into commercially available diagnostic manometry systems for more than a decade. This innovation, which offered the ability to record patterns of bolus transport without the need for simultaneous radiology, has for the most part failed to live up to expectations, offering few additional diagnostic insights. This review examines the potential pitfalls related to how impedance patterns are currently analysed and introduces and discusses the new concept of pressure-flow analysis integrating pressure and impedance measurements to derive new metrics linked to the pressures occurring within and around the bolus as it is being transported.

High-resolution Impedance Manometry Criteria in the Sitting Position Indicative of Incomplete Bolus Clearance

BACKGROUND/AIMS

We used high-resolution impedance manometry (HRIM) to determine the length of breaks on the isobaric contour which would predict incomplete bolus clearance in patients in the sitting position.

METHODS

In total, 651 swallows in 71 patients with esophageal symptoms were studied using a solid-state HRIM system in the sitting position. Each swallow was classified as complete or incomplete bolus clearance by impedance criteria and peristaltic integrity was evaluated using 20- and 30-mmHg pressure topography isobaric contours. Correlations between the lengths of the breaks for 20- and 30-mmHg were analyzed.

RESULTS

Complete bolus clearance was observed in 83.3% (542/651) of swallows. Breaks of 3 and 7 cm or less were associated with a bolus clearance of 96.8% on the 20-mmHg and 94.7% on the 30-mmHg isobaric contour, respectively (P < 0.001). The areas under the ROC curves for the 20 and 30 mmHg isobaric contours were 0.900 and 0.950, respectively. The sensitivity and specificity for complete bolus clearance were 75.6% and 89.3% for breaks 3 cm or less on the 20-mmHg isobaric contour and 87.9% and 78.7% for breaks 7 cm or less on the 30-mmHg contour (P < 0.001).

CONCLUSIONS

Breaks of < 3 cm in the 20-mmHg isobaric contour or < 7 cm in the 30-mmHg isobaric contour were associated with com-plete bolus clearance. The threshold for breaks in the sitting position was greater than previous reports using the supine posi-tion and longer breaks predicted incomplete bolus clearance.(J Neurogastroenterol Motil 2014;20:491-496).

Applying the Chicago Classification criteria of esophageal motility to a pediatric cohort: effects of patient age and size

BACKGROUND

Applying the 2012 Chicago Classification (CC) of esophageal motility disorders to pediatric patients is problematic as it relies upon adult-derived criteria. As shorter esophageal length and smaller esophago-gastric junction (EGJ) diameter may influence CC metrics, we explored the potential for age- and size-adjustment of diagnostic criteria.

METHODS

We evaluated 76 high-resolution solid state impedance-manometry recordings in children referred for manometry (32M; mean age 9 ± 1 years) and 25 recordings from healthy adult subjects (7M; mean age 36 ± 2 years). CC metrics; integrated relaxation pressure (IRP4s, mmHg), contractile front velocity (CFV, cm/s), distal contractile integral (DCI, mmHg cm/s), distal latency (DL, s), and peristaltic break size (BS, cm) were derived for 10 liquid swallows using CC analysis software. Effects of age and size were examined using regression analysis.

KEY RESULTS

Younger patient age and shorter size correlated significantly with greater IRP4s (p < 0.05), shorter DL (p < 0.001) and smaller BS (p < 0.05). Standard diagnostic CC criteria were adjusted using the slope of the linear regression equation to define the age/size-related trend. Sixty-six percent of the pediatric cohort showed abnormal motility when applying standard CC criteria. Adjustment for age and size reduced this to 50% and 53% respectively, with the largest reduction being in the IRP4s- and DL-dependent disorders EGJ outflow obstruction and diffuse esophageal spasm (13% to 7% and 5% and 14% to 1 and 5%, respectively).

CONCLUSIONS & INFERENCES

CC metrics, particularly IRP4s and DL, are age and size dependent, and therefore, require adjustment to improve accuracy of diagnosis of esophageal motility disorders in children.

Sensation of stasis is poorly correlated with impaired esophageal bolus transport

BACKGROUND

It is common belief that symptoms of patients with non-obstructive dysphagia are the result of impaired bolus clearance in the esophagus, usually caused by esophageal motility disorders. We therefore investigated the relationship between transit of swallowed boluses and the symptom dysphagia.

METHODS

Twenty healthy volunteers and 20 patients with dysphagia underwent videofluoroscopy. Success of bolus transport was graded on a 7-point scale. Each subject swallowed five liquid and five solid barium boluses.

KEY RESULTS

For liquids, patients reported dysphagia during 1 [0-3] of the five swallows, while controls reported no dysphagia (median 0 [0-0]; p = 0.003). For solids, patients reported dysphagia during 3 [2-4] of five swallows, while controls reported dysphagia in 0.5 [0-2] of five swallows (p = 0.001). When correlating dysphagia to ineffective clearance (score ≥ 3), in 3 [2-4] of five liquids, the subjects perception of clearance was related to the clearance result on fluoroscopy in patients and also 3 [1-5] were correctly perceived in controls (p = 0.6). For solids, in 4 [3-5] of five swallows, the subjects perception of clearance was related to the clearance result on fluoroscopy in patients, but only 2 [1-3] of five swallows were correctly perceived by controls, the difference being statistically significant.

CONCLUSIONS & INFERENCES

Patients very frequently report dysphagia when bolus clearance is successful. Therefore, the major underlying problem in patients with non-obstructive dysphagia is disordered perception and increased sensitivity to physiological bolus stasis. Treatment should therefore be directed at reducing increased sensitivity rather than at improving motility.

Esophageal Motility in the Supine and Upright Positions for Liquid and Solid Swallows Through High-resolution Manometry

Background/Aims

Most recent studies using high-resolution manometry were based on supine liquid swallows. This study was to evaluate the differences in esophageal motility for liquid and solid swallows in the upright and supine positions, and to determine the percentages of motility abnormalities in different states.

Methods

Twenty-four asymptomatic volunteers and 26 patients with gastroesophageal reflux disease underwent high-resolution manometry using a 36-channel manometry catheter. The peristalses of 10 water and 10 steamed bread swallows were recorded in both supine and upright positions. Integrated relaxation pressure, contractile front velocity, distal latency (DL) and the distal contractile integral (DCI) were investigated and comparisons between postures and boluses were analyzed. Abnormal peristalsis of patients was assessed applying the corresponding normative values.

Results

In total, 829 swallows from healthy volunteers and 959 swallows from patients were included. (1) The upright position provided lower integrated relaxation pressure, shorter DL and weaker DCI than the supine position. (2) In the comparison of liquid swallows, the mean for contractile front velocity was obviously reduced while DL and DCI were increased in solid swallows. (3) The supine position detected more hypotensive peristalsis than the upright position. The upright position provided more rapid and premature contraction than the supine position but there was no statistically significant difference.

Conclusions

Supine solid swallows occur with more hypotensive peristalsis. Analysis should be based on normative values from the corresponding posture and bolus.

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.

Esophageal contractions, bolus transit and perception of transit after swallows of liquid and solid boluses in normal subjects

CONTEXT: Esophageal dysphagia is the sensation that the ingested material has a slow transit or blockage in its normal passage to the stomach. It is not always associated with motility or transit alterations. OBJECTIVES: To evaluate in normal volunteers the possibility of perception of bolus transit through the esophagus after swallows of liquid and solid boluses, the differences in esophageal contraction and transit with these boluses, and the association of transit perception with alteration of esophageal contraction and/or transit. METHODS: The investigation included 11 asymptomatic volunteers, 4 men and 7 women aged 19-58 years. The subjects were evaluated in the sitting position. They performed swallows of the same volume of liquid (isotonic drink) and solid (macaroni) boluses in a random order and in duplicate. After each swallow they were asked about the sensation of bolus passage through the esophagus. Contractions and transit were evaluated simultaneously by solid state manometry and impedance. RESULTS: Perception of bolus transit occurred only with the solid bolus. The amplitude and area under the curve of contractions were higher with swallows of the solid bolus than with swallows of the liquid bolus. The difference was more evident in swallows with no perception of transit (n = 12) than in swallows with perception (n = 10). The total bolus transit time was longer for the solid bolus than for the liquid bolus only with swallows followed by no perception of transit. CONCLUSION: The results suggest that the perception of esophageal transit may be the consequence of inadequate adaptation of esophageal transit and contraction to the characteristics of the swallowed bolus.

High-resolution Manometry: Esophageal Disorders Not Addressed by the "Chicago Classification"

The development of the high-resolution esophageal manometry (HRM) and the Chicago classification have improved the diagnosis and management of esophageal motility disorders. However, some conditions have yet to be addressed by this classification. This review describes findings in HRM which are not included in the current Chicago classification based on the experience in our center. This includes the analysis of the upper esophageal sphincter, proximal esophagus, longitudinal muscle contraction, disorders related to gastroesophageal reflux disease and respiratory symptoms. The utility of provocative tests and the use of HRM in the evaluation of rumination syndrome and post-surgical patients will also be discussed. We believe that characterization of the manometric findings in these areas will eventually lead to incorporation of new criteria into the existing classification.

Optimizing the swallow protocol of clinical high-resolution esophageal manometry studies

BACKGROUND

The Chicago Classification (CC) of Esophageal Motility Disorders is based on 10 water swallows performed in the supine position. The aim of the study was to assess whether upright and provocative swallows (PS) provided important information beyond that obtained from the standard supine manometric protocol.

METHODS

Two independent investigators reviewed high-resolution manometry (HRM) studies of 148 patients with both supine and upright liquid swallows and additional studies from patients with PS (increased volume, viscosity, and a marshmallow) for a resultant change in CC diagnoses. Significant diagnostic changes were defined as a change from normal or borderline motor function to abnormal motor function, esophagogastric junction (EGJ) outflow obstruction, or achalasia. Discordant diagnoses were reviewed and the Kappa test was used to evaluate the agreement between diagnoses in the different protocols.

KEY RESULTS

The overall agreement in diagnosis between the five supine swallows and the five upright swallows was good (k = 0.583). Changing to the upright position elicited a significant diagnostic change in 10.1% (15/148) of cases. The PS suggested an alternative diagnosis from the supine position in 14 of 75 studies (18.7%); 11 of these changed to EGJ obstruction during viscous or solid bolus challenges.

CONCLUSIONS & INFERENCES

Changing position in HRM elicited a significant change in diagnosis in about 10% of studies, whereas provocative bolus challenges with viscous liquid and marshmallows increased the detection of EGJ outflow obstruction. Performing manometric evaluations in both positions with PS may increase the yield of standard HRM technique.

The effect of a sitting vs supine posture on normative esophageal pressure topography metrics and Chicago Classification diagnosis of esophageal motility disorders

BACKGROUND

Although, the current protocol for high resolution manometry (HRM) using the Chicago Classification is based on the supine posture, some practitioners prefer a sitting posture. Our aims were to establish normative esophageal pressure topography data for the sitting position and to determine the effect of applying those norms to Chicago Classification diagnoses.

METHODS

Esophageal pressure topography studies including test swallows in both a supine and sitting position of 75 healthy volunteers and 120 patients were reviewed. Integrated relaxation pressure (IRP), distal contractile integral (DCI), contractile front velocity (CFV), and distal latency were measured and compared between postures. Normative ranges were established from the healthy volunteers and the effect of applying sitting normative values to the patients was analyzed.

KEY RESULTS

Normative values of IRP, DCI, and CFV all decreased significantly in the sitting posture. Applying normative sitting metrics to patient studies [27% reduction in IRP (15 to 11 mmHg), 69% reduction in DCI (8000-2500 mmHg-s-cm)] reclassified 13/120 (11%) patients as having abnormal esophagogastric junction relaxation and 26/120 (22%) as hypercontractile. Three patients with an abnormal supine IRP normalized when sitting with elimination of a vascular artifact.

CONCLUSIONS & INFERENCES

Clinical HRM studies should include both a supine and sitting position to minimize misdiagnoses attributable to anatomical factors. However, until outcome studies demonstrating the significance of isolated abnormalities of IRP or DCI in the sitting position are available, the Chicago Classification of esophageal motility disorders should continue to be based on supine swallows using normative data from the supine posture.

High-resolution manometry

The following presents commentaries on the interest of high-resolution manometry for understanding the anatomy and physiology of the esophagogastric junction; the subtypes of achalasia, as diagnosed by high-resolution manometry; the interest of high-resolution manometry in the evaluation of dysphagia following fundoplication; and the appropriate clinical protocol for high-resolution manometry.

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.

Apple sauce improves detection of esophageal motor dysfunction during high-resolution manometry evaluation of dysphagia

BACKGROUND

Esophageal manometry utilizes water swallows to evaluate esophageal motor abnormalities in patients with dysphagia, chest pain, or reflux symptoms. Although manometry is the gold standard for evaluation of these symptoms, patients with dysphagia often have normal results in manometry studies.

AIM

The objective of this work was to test the hypothesis that challenging the esophagus with viscous apple sauce boluses uncovers motor abnormalities in patients with dysphagia not seen when using water swallows.

METHODS

High-resolution esophageal manometry was performed using ten water swallows followed by ten apple sauce swallows in consecutive subjects presenting with dysphagia. Subjects with grossly abnormal water swallow evaluations were excluded. Each swallow was categorized as normal, hypotensive (distal isobaric contour plots of < 30 mmHg over >5 cm), or simultaneous (distal esophageal velocity ≥ 8.0 cm/s). Ineffective esophageal motility (IEM) was defined as ≥ 30% hypotensive swallows, and pressurization was defined as ≥ 20% simultaneous pressure waves.

RESULTS

Data from 41 subjects was evaluated. Overall, 96.3% of water swallows were normal, 2.9% hypotensive, and 0.7% simultaneous. Only 70.3% of viscous swallows were normal; 16.7% were hypotensive and 13.0% were simultaneous (P < 0.001 all groups). Seven (17.1%) met criteria for IEM, and pressurization with viscous swallows was observed for nine (22.0%). Fourteen subjects (34.1%) had abnormal results from viscous studies. The presence of any abnormal water swallows was predictive of abnormal viscous swallows (OR = 9.00, CI = 2.15-80.0), although the presence of hypotensive or simultaneous water swallows was not associated with IEM (OR = 0.63, CI = 0.16-2.17) or pressurization (OR = 7.00, CI = 0.90-315.4) with viscous apple sauce.

CONCLUSIONS

Apple sauce challenge increased identification of classifiable motor disorders in patients with dysphagia and may be preferred to alternative bolus materials.

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.