Transient hypopharyngeal intrabolus pressurization patterns: Clinically relevant or normal variant?

Defining Pharyngeal and Upper Esophageal Sphincter Disorders on High-Resolution Manometry-Impedance: The Leuven Consensus

INTRODUCTION

The Leuven Consensus provides a classification scheme for the diagnosis of pharyngeal and upper esophageal sphincter (UES) motor disorders using metrics derived from pharyngeal high-resolution manometry-impedance (P-HRM-I).

METHODS

Twenty-six experts with broad multidisciplinary backgrounds contributed their knowledge and experience to this initiative via a formal deliberative Delphi process. Guidance on a swallow assessment protocol as well as diagnostic criteria for UES dysfunction and pharyngeal contractile dysfunction is provided.

RESULTS

For UES dysfunction, the stepwise evaluation of UES and intrabolus pressure metrics under increasing bolus volume and/or viscosity conditions is used to confirm failure of manometric relaxation and opening of the UES region. For pharyngeal contractile dysfunction, the evaluation of contractile metrics is used to define pharyngeal hypocontractility or hypercontractility.

CONCLUSION

These recommendations complement routine instrumental investigations and provide a standardized process, criteria, and nomenclature for P-HRM-I assessment of patients reporting symptoms of oropharyngeal dysphagia.

Effect of Thickened Fluids on Swallowing Function in Oropharyngeal Dysphagia: Impact of Shear Rheology and Disorder Subtype

INTRODUCTION

Fluid thickeners used in the management of oropharyngeal dysphagia exhibit non-Newtonian shear-thinning rheology, impacting their viscosity during deglutition. This study investigated how the rheological properties of thickened fluids affect pharyngeal swallowing parameters in patients with oropharyngeal motor disorders diagnosed by pharyngeal high-resolution manometry impedance (P-HRM-I).

METHODS

Seventy-two patients (18-89 years) referred for P-HRM-I were diagnostically assessed with a 10 mL thin bolus. In 57 of the patients, 10 mL swallows of two moderately thick formulations-xanthan gum (XG) and sodium carboxymethylcellulose gum (CMC)-were also tested. The XG and CMC fluids had equivalent empirical thickness but different viscosity at pharyngeal phase shear rates: XG 87 mPa.s (83-91) versus CMC mean 157 mPa.s (148-164) at 300 s-1. Standard metrics of pharyngeal and upper esophageal sphincter (UES) function were derived from P-HRM-I recordings and analyzed to characterize patients into one of four disorder subtypes: (i) No Disorder, (ii) UES Disorder, (iii) Pharyngeal Disorder, and (iv) Combination UES/Pharyngeal Disorder. Impedance recordings also assessed pharyngeal bolus transit.

RESULTS

Patients with a Combination UES/Pharyngeal Disorder were most likely to have abnormal bolus transit (82%, p < 0.001). Increasing bolus viscosity significantly influenced UES residual pressure, UES opening area, and post-swallow residue. Patients with UES Disorder exhibited pronounced increases in UES residual pressure with CMC compared to XG. Pharyngeal contractility was unaffected by viscosity changes. Post-swallow residue increased with CMC, particularly in patients with a Combination Disorder. Case-by-case analysis revealed individual variability in response to the different viscosities.

CONCLUSION

The rheological properties of thickened fluids significantly affect swallowing function, with these effects dependent upon the disorder subtype.

Normative High-Resolution Pharyngeal Manometry: Impact of Age, Size of System, and Sex on Primary Metrics and Pressure Stability

There have been many reports of normative pharyngeal swallowing pressures using high-resolution pharyngeal manometry, but there is a fair amount of between-subject variance in reported pressure parameters. The purpose of this study was to put forward normative pharyngeal high-resolution manometry measures across the lifespan and investigate the effects of age, size of system, and sex. High-resolution pharyngeal manometry was performed on 98 healthy adults (43 males) between the ages 21 and 89. Pressure duration, maxima, integral, and within-individual variability metrics were averaged over 10 swallows of 10-ml thin liquid. Multiple linear and logistic regressions with model fitting were used to examine how pharyngeal pressures relate to age, pharyngeal size, and sex. Age was associated with tongue base maximum pressure, tongue base maximum variability, and upper esophageal sphincter-integrated relaxation pressure (F3,92 = 6.69; p < 0.001; adjusted R2 = 0.15). Pharyngeal area during bolus hold was associated with velopharynx integral (F1,89 = 5.362; p = 0.02; adjusted R2 = 0.05), and there was no significant model relating pharyngeal pressures to C2-C4 length (p < 0.05). Sex differences were best described by tongue base integral and hypopharynx maximum variability (χ2 = 10.27; p = 0.006; pseudo R2 = 0.14). Normative data reveal the distribution of swallow pressure metrics which need to be accounted for when addressing dysphagia patients, the importance of pressure interactions in normal swallow, and address the relative stability of swallow metrics with normal aging.

Interpretation of Impedance Data on High-resolution Impedance Manometry Studies-A Worldwide Survey

Background/Aims

Esophageal manometry is the gold standard for esophageal motility evaluation. High-resolution esophageal manometry with impedance (HRIM) allows concurrent assessment of bolus transit and manometry. Inconsistencies between concomitant impedance and manometry data pose a clinical dilemma and has not yet been addressed. We aim to assess interpretation trends of HRIM data among gastroenterologists worldwide.

Methods

A cross-sectional study using an anonymous survey was conducted among gastroenterologists worldwide. Statistical analysis was performed to compare responses between providers.

Results

We received responses from 107 gastroenterologists (26 countries). Most were adult providers (69, 64.5%), and most (77, 72.0%) had > 5 years of experience. Impedance was found to be helpful by 83 (77.6%) participants, but over 30% reported inconsistencies between impedance and manometry data. With incomplete bolus clearance and normal manometry 41 (38.7%) recommended observation, 41 (38.7%) recommended 24-hours pH-impedance, and 16 (15.1%) recommended prokinetics. With abnormal manometry and complete bolus clearance, 60 (57.1%) recommended observation while 18 (17.1%) recommended 24-hours pH impedance and 15 (14.3%) recommended prokinetics. A significant difference was found between providers from different continents in treating cases with discrepancy between impedance and manometry findings (P < 0.001). No significant differences were seen in responses between adult versus pediatric providers and between providers with different years of experience.

Conclusions

There is no consensus on interpreting HRIM data. Providers' approaches to studies with inconsistencies between manometry and impedance data vary. There is an unmet need for guidelines on interpreting impedance data in HRIM studies.

Upper Esophageal Sphincter Metrics across Eosinophilic Esophagitis, Gastroesophageal Reflux Disease and Functional Dysphagia: A Pilot Study

BACKGROUND

Recent studies have evaluated the upper esophageal sphincter (UES) with high-resolution manometry (HRM) in some esophageal diseases, but not eosinophilic esophagitis (EoE). The aim of our study was to evaluate the function of the UES across EoE, gastroesophageal reflux disease (GERD), functional dysphagia (FD), and the relationship with esophageal symptoms, esophageal body contraction, and esophagogastric junction (EGJ) metrics.

METHODS

HRM was performed on 30 EoE, 18 GERD, and 29 FD patients according to the Chicago Classification 3.0. The study data were exported to the online analysis platform Swallow Gateway. The UES was assessed in terms of UES Resting Pressure (UES-RP), UES Basal Pressure (UES-BP), UES Integrated Relaxation Pressure (UES-IRP), UES Relaxation Time (UES-RT), Basal UES Contractile Integral (Basal UES-CI), Post-Deglutitive UES Contractile Integral (Post-Deglutitive UES-CI), and Proximal Contractile Integral (PCI).

RESULTS

ANOVA analysis showed significantly higher values of Post-Deglutitive UES-CI in EoE patients compared with FD patients (p = 0.001). Basal UES-CI and UES-RP showed significantly higher values in EoE (p = 0.002, p = 0.038) and GERD (p < 0.001, p = 0.001) patients compared with FD patients. Correlations between LES-CI and Post-Deglutitive UES-CI, Basal UES-CI, and UES-RP (p ≤ 0.001, p = 0.027, p = 0.017, respectively), and between LES-BP and Post-Deglutitive UES-CI (p = 0.019), independent of diagnosis, were shown. No correlations have been demonstrated between the UES, EGJ metrics, and esophageal symptoms.

CONCLUSIONS

Some differences in UES metrics in the three different diseases were found. Further studies are needed to confirm the results of our pilot study and possible applications in clinical practice.

Distension contraction plots of pharyngeal/esophageal peristalsis: next frontier in the assessment of esophageal motor function

Esophageal peristalsis consists of initial inhibition (relaxation) followed by excitation (contraction), both of which move sequentially in the aboral direction. Initial inhibition results in receptive relaxation and bolus-induced luminal distension, which allows propulsion by the contraction with minimal resistance to flow. Similar to the contraction wave, luminal distension has unique waveform characteristics in normal subjects; both are modulated by bolus volume, bolus viscosity, and posture, suggesting a possible cause-and-effect relationship between the two. Distension contraction plots in patients with dysphagia with normal bolus clearance [high-amplitude esophageal contractions (HAECs), esophagogastric junction outflow obstruction (EGJOO), and functional dysphagia (FD)] reveal two major findings: 1) unlike normal subjects, there is luminal occlusion distal to bolus during peristalsis in certain patients, i.e., with type 3 achalasia and nonobstructive dysphagia; and 2) bolus travels through a narrow lumen esophagus during peristalsis in patients with HAECs, EGJOO, and FD. Aforementioned findings indicate a relative dynamic obstruction to the bolus flow during peristalsis and reduced distensibility of esophageal wall in the bolus segment of the esophagus. We speculate that a normal or supernormal contraction wave pushing bolus against resistance is the mechanism of dysphagia sensation in significant number of patients. Representations of distension and contraction, combined with objective measures of flow timing and distensibility are complementary to the current scheme of classifying esophageal motility disorders based solely on the characteristics of contraction phase of peristalsis. Better understanding of the distensibility of the bolus-containing segment of the esophagus during peristalsis will lead to the development of novel medical and surgical therapies in the treatment of dysphagia in significant number of patients.