Bolus Flow Research Articles

Phrenic Ampulla Emptying Dysfunction in Patients with Esophageal Symptoms.

Pharyngeal pump, esophageal peristalsis, and phrenic ampulla emptying play important roles in the propulsion of bolus from the mouth to the stomach. There is limited information available on the mechanism of normal and abnormal phrenic ampulla emptying. The goal of our study is to describe the relationship between bolus flow and esophageal pressure profiles during the phrenic ampulla emptying in normal subjects and patient with phrenic ampulla dysfunction. Pressure (using topography) and bolus flow (using changes in impedance) relationship through the esophagus and phrenic ampulla were determined in 15 normal subjects and 15 patients with retrograde escape of bolus from the phrenic ampulla into esophagus during primary peristalsis. During the phrenic ampulla phase, 2 high pressure peaks (proximal, related to lower esophageal sphincter and distal, related to crural diaphragm) were observed in normal subjects and patients during the phrenic ampulla emptying phase. The proximal was always higher than the distal one in normal subjects; in contrast, reverse was the case in patients with the retrograde escape of bolus from the phrenic ampulla into the esophagus. We propose that a strong after-contraction of the lower esophageal sphincter plays an important role in the normal phrenic ampullary emptying. A defective lower esophageal after-contraction, along with high crural diaphragm pressure are responsible for the phrenic ampulla emptying dysfunction.

The origin of intraluminal pressure waves in gastrointestinal tract.

The gastrointestinal (GI) peristalsis is an involuntary wave-like contraction of the GI wall that helps to propagate food along the tract. Many GI diseases, e.g., gastroparesis, are known to cause motility disorders in which the physiological contractile patterns of the wall get disrupted. Therefore, to understand the pathophysiology of these diseases, it is necessary to understand the mechanism of GI motility. We present a coupled electromechanical model to describe the mechanism of GI motility and the transduction pathway of cellular electrical activities into mechanical deformation and the generation of intraluminal pressure (IP) waves in the GI tract. The proposed model consolidates a smooth muscle cell (SMC) model, an actin-myosin interaction model, a hyperelastic constitutive model, and a Windkessel model to construct a coupled model that can describe the origin of peristaltic contractions in the intestine. The key input to the model is external electrical stimuli, which are converted into mechanical contractile waves in the wall. The model recreated experimental observations efficiently and was able to establish a relationship between change in luminal volume and pressure with the compliance of the GI wall and the peripheral resistance to bolus flow. The proposed model will help us understand the GI tract's function in physiological and pathophysiological conditions.

Esophago-gastric junction findings on high resolution impedance manometry in children with esophageal atresia.

Using high resolution impedance manometry (HRIM), this study characterized the esophago-gastric junction (EGJ) dynamics in children with esophageal atresia (EA). Esophageal HRIM was performed in patients with EA aged less than 18 years. Objective motility patterns were analyzed, and EGJ data reported. Controls were pediatric patients without EA undergoing investigations for consideration of fundoplication surgery. Seventy-five patients (M:F = 43:32, median age 1 year 3 months [3 months-17 years 4 months]) completed 133 HRIM studies. The majority (64/75, 85.3%) had EA with distal tracheo-esophageal fistula. Compared with controls, liquid swallows were poorer in patients with EA, as evident by significant differences in distension pressure emptying and bolus flow time (BFT). The integrated relaxation pressure for thin liquid swallows was significantly different between EA types, as well as when comparing patients with EA with and without previous esophageal dilatations. The BFT for solid swallows was significantly different when compared with EA types. We have utilized HRIM in patients with EA to demonstrate abnormalities in their long-term EGJ function. These abnormalities correlate with poorer esophageal compliance and reduced esophageal peristalsis across the EGJ. Understanding the EGJ function in patients with EA will allow us to tailor long-term management to specific patients.

Endoscopic Biofeedback Training for Cough and Swallowing: The What, Why, and How

Purpose: Endoscopic biofeedback training is a type of augmented extrinsic feedback that provides information about physiological processes and bolus flow information through the use of flexible endoscopy. The goal of this tutorial is to describe why and how to incorporate endoscopic biofeedback training into cough and swallowing treatment when working with people with dystussia and dysphagia. Method: In this tutorial, we will review the diagnostic advantages and limitations of flexible endoscopic evaluation of swallowing as it relates to biofeedback training. We will then (a) review what is known about endoscopic biofeedback training in the field of speech-language pathology; (b) identify which airway protective behaviors clinicians might be best suited for endoscopic biofeedback training; and (c) provide a guide, including sample scripts and video demonstrations, that clinicians can use to aide in the implementation of endoscopic biofeedback training. Conclusions: Endoscopic biofeedback training for cough and swallowing habilitation and rehabilitation may be a useful addition to a speech-language pathologist's therapeutic armamentarium. However, more research is needed to comprehensively characterize the long-term effects on endoscopic biofeedback training on cough and swallowing treatment-related outcomes. Supplemental Material: https://doi.org/10.23641/asha.25043579

Prediction of Pharyngeal 3D Volume Using 2D Lateral Area Measurements During Swallowing.

This study evaluated the validity of pharyngeal 2D area measurements acquired from the lateral view for predicting the actual 3D volume in healthy adults during swallowing. Seventy-five healthy adults (39 females, 36 males; mean age 51.3years) were examined using 320-row area detector computed tomography (320-ADCT). All participants swallowed a 10mL honey-thick barium bolus upon command while seated in a 45° semi-reclining position. Multi-planar reconstruction images and dynamic 3D-CT images were obtained using Aquilion ONE software. Pharyngeal 2D area and 3D volume measurements were taken before swallowing and at the frame depicting maximum pharyngeal constriction. Pharyngeal volume before swallowing (PVhold) was accurately predicted by 2D area (R2 = 0.816). Adding height and sex to the model increased R2 to 0.836. Regarding pharyngeal volume during maximum constriction (PVmax), 2D area also exhibited acceptable predictive power (R2 = 0.777). However, analysis of statistical residuals and outliers revealed a greater tendency for prediction errors when there is less complete constriction of the pharynx as well as asymmetry in bolus flow or movement. Findings highlight the importance of routinely incorporating anterior-posterior views during VFSS exams. Future work is needed to determine clinical utility of pharyngeal volume measurements derived from 320-ADCT.

A perspective on the clinical relevance of weak or nonacid reflux.

Advances in ambulatory esophageal reflux monitoring that incorporated impedance electrodes to pH catheters have resulted in better characterization of retrograde bolus flow in the esophagus. With pH-impedance monitoring, in addition to acid reflux episodes identified by pH drops below 4.0, weakly acid reflux (WAR, pH 4-7) and nonacid reflux (NAR, pH >7.0) are also recognized, although both may be included under the umbrella term NAR. However, despite identification of ambulatory pH-impedance monitoring, data on clinical relevance and prognostic value of NAR are limited. The Lyon Consensus, an international expert review that defines conclusive metrics for gastroesophageal reflux disease (GERD), identifies NAR as "supportive" but not conclusive for GERD. This review provides perspectives on whether NAR fulfills three criteria for clinical relevance: whether NAR sufficiently explains pathogenesis of symptoms, whether it is associated with meaningful manifestations of GERD, and whether it can predict treatment efficacy.

Bronchoscopist-Directed Continuous Flow Propofol Based Analgosedation during Flexible Interventional Bronchoscopy and EBUS.

Sedation techniques in interventional flexible bronchoscopy and endobronchial ultrasound-guided transbronchial-needle aspiration (EBUS-TBNA) are inconsistent and the evidence for required general anesthesia under full anesthesiologic involvement is scarce. Moreover, we faced the challenge of providing bronchoscopic care with limited personnel. Hence, we retrospectively identified 513 patients that underwent flexible interventional bronchoscopy and/or EBUS-TBNA out of our institution between January 2020 and August 2022 to evaluate our deep analgosedation approach based on pethidine/meperidine bolus plus continuous flow adjusted propofol, the bronchoscopist-directed continuous flow propofol based analgosedation (BDcfP) in a two-personnel setting. Consequently, 502 out of 513 patients received BDcfP for analgosedation. We identified cardiovascular comorbidities, chronic obstructive pulmonary disease, and arterial hypertension as risk factors for periprocedural hypotension. Propofol flow rate did not correlate with hypotension. Theodrenaline and cafedrine might be used to treat periprocedural hypotension. Moreover, midazolam might be used to support the sedative effect. In conclusion, BDcfP is a safe and feasible sedative approach during interventional flexible bronchoscopy and EBUS-TBNA. In general, after the implementation of safety measures, EBUS-TBNA and interventional flexible bronchoscopy via BDcfP might safely be performed even with limited personnel.

The Modified Barium Swallow Study and Esophageal Screening: A Survey of Clinical Practice Patterns

Modified barium swallow study (MBSS) is a videofluoroscopic evaluation of oropharyngeal swallowing. Views of esophageal bolus flow during MBSS are permitted under speech-language pathology practice guidelines. However, controversy exists over its implementation. Poor consensus and limited practice guidance may lead to clinical practice variations. Aims of the investigation were to (a) describe current practice patterns of speech-language pathologist visualizing bolus flow through the esophagus during the MBSS, (b) understand areas of variation when incorporating esophageal visualization during the MBSS, and (c) determine clinicians' willingness to modify MBSS procedures to include esophageal imaging. A web-based survey (Qualtrics XM) consisting of 26 questions was distributed via web posting and e-mail to members of the American Speech-Language-Hearing Association Special Interest Group 13 and Dysphagia Café. The survey was open for 3 months. Descriptive and associative statistics were completed. Field-testing was performed prior to dissemination of the survey to address content validity. A total of 321 individuals participated; 265 responses were used for analysis. Ninety-three percent of respondents viewed the esophagus during the MBSS. Twelve percent followed to the proximal esophagus, 15% to the mid esophagus, 66% to the lower esophagus, and 6% to varied levels. Variability was also reported in contrast type, volume administered, and nomenclature used. Interestingly, few people (3.61%) disagreed that esophageal visualization should be performed during MBSS. Speech-language pathology respondents in this study visualize contrast flow through the esophagus and are enthusiastic about expanding the standard MBSS. However, results of the survey demonstrate a lack of uniformity in assessment practices. Unfortunately, this may impact the diagnostic accuracy and clinical utility when adding esophageal visualization to the MBSS. This study highlights the need for a standardized protocol and identifies current barriers and controversies that may prevent expanding the MBSS to more comprehensively evaluate individuals with dysphagia.

Biomechanical effects of esophageal elongation on the circumferential tension of the cervical esophagus in vivo.

Evidence obtained ex vivo suggests that physical elongation of the esophagus increases esophageal circumferential stress-strain ratio, but it is unknown whether this biomechanical effect alters esophageal function in vivo. We investigated the effects of physical or physiological elongation of the cervical esophagus on basal and active circumferential tension in vivo. The esophagus was elongated, using 29 decerebrate cats, either physically by distal physical extension of the esophagus or physiologically by stimulating the hypoglossal nerve, which activates laryngeal elevating muscles that elongate the esophagus. Hyoid, pharyngeal, and esophageal muscles were instrumented with electromyogram (EMG) electrodes and/or strain gauge force transducers. Esophageal intraluminal manometry was also recorded. We found that physical or physiological elongation of the cervical esophagus increased esophageal circumferential basal as well as active tension initiated by electrical stimulation of the pharyngo-esophageal nerve or the esophageal muscle directly, but did not increase esophageal intraluminal pressure or EMG activity. The esophageal circumferential response to the esophago-esophageal contractile reflex was increased by distal physical elongation, but not orad physiological elongation. We conclude that physical or physiological elongation of the esophagus significantly increases esophageal circumferential basal and active tension without muscle activation. We hypothesize that this effect is caused by an increase in esophageal stress-strain ratio by a biomechanical process, which increases circumferential wall stiffness. The increase in esophageal circumferential stiffness increases passive tension and the effectiveness of active tension. This increase in cervical esophageal circumferential stiffness may alter esophageal function.NEW & NOTEWORTHY Physical or physiological esophageal elongation increases esophageal circumferential active or passive tension by a biomechanical process, which causes a decrease in esophageal circumferential elasticity. This increased stiffness of the esophageal wall likely promotes esophageal bolus flow during various esophageal functions.

Peristaltic regimes in esophageal transport.

A FLIP device gives cross-sectional area along the length of the esophagus and one pressure measurement, both as a function of time. Deducing mechanical properties of the esophagus including wall material properties, contraction strength, and wall relaxation from these data are a challenging inverse problem. Knowing mechanical properties can change how clinical decisions are made because of its potential for in-vivo mechanistic insights. To obtain such information, we conducted a parametric study to identify peristaltic regimes by using a 1D model of peristaltic flow through an elastic tube closed on both ends and also applied it to interpret clinical data. The results gave insightful information about the effect of tube stiffness, fluid/bolus density and contraction strength on the resulting esophagus shape through quantitive representations of the peristaltic regimes. Our analysis also revealed the mechanics of the opening of the contraction area as a function of bolus flow resistance. Lastly, we concluded that peristaltic driven flow displays three modes of peristaltic geometries, but all physiologically relevant flows fall into two peristaltic regimes characterized by a tight contraction.

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.

EndoFLIP Topography: Motor Patterns in an Obstructed Esophagus

EndoFLIP Topography: Motor Patterns in an Obstructed Esophagus

Chin tuck against resistance exercise with feedback to improve swallowing, eating and drinking in frail older people admitted to hospital with pneumonia: protocol for a feasibility randomised controlled study

BackgroundSwallowing difficulties (dysphagia) and community-acquired pneumonia are common in frail older people and maybe addressed through targeted training of the anterior neck musculature that affects the swallow. We have developed a swallowing exercise rehabilitation intervention (CTAR-SwiFt) by adapting a previously established swallowing exercise to ensure patient safety and ease of execution in the frail elderly population. The CTAR-SwiFt intervention consists of a feedback-enabled exercise ball that can be squeezed under the chin, with real-time feedback provided via a mobile application. The aim of this study is to evaluate the feasibility of assessing the effectiveness of the CTAR-SwiFt intervention in reducing dysphagia and community-acquired pneumonia, prior to a larger-scale multi-centre randomised controlled trial.MethodsWe will recruit 60 medically stable patients over the age of 75 years who have been admitted with a diagnosis of pneumonia to the acute frailty wards at two participating hospitals in the UK. Study participants will be randomised into one of three groups: standard care, low intensity (once daily) CTAR-SwiFt exercise or high intensity (twice daily) CTAR-SwiFt exercises. The intervention period will last for 12 weeks, the final follow-up assessment will be conducted at 24 weeks. We will assess the feasibility outcomes, including rates of participant recruitment and retention, compliance with the exercise regime and adverse incidents. Additionally, we will assess the usability and acceptability of the intervention device and the performance of different clinical outcome measures (e.g. chin tuck strength, Functional Oral Intake Scale, SWAL-QOL, EQ-5D and swallow speed). A sub-sample of study participants will complete videofluoroscopic assessments of swallowing function before and after the intervention to evaluate the physiological changes (e.g. bolus flow rates, laryngeal elevation, base-of-tongue retraction).ConclusionsBy improving the ability to swallow, using our chin tuck exercise intervention, in frail older patients admitted to hospital with pneumonia, it is anticipated that patients’ oral intake will improve. It is suggested that this will further impact clinical, patient and healthcare economic outcomes, i.e. reduce the need for supplemental feeding, improve patient satisfaction with oral intake and swallowing-related quality of life, decrease the occurrence of chest infections and reduce hospital admissions and related healthcare costs.Trial registrationISRCTN, ISRCTN12813363. Registered on 20 January 2020

Swallowing Kinematics in Rats Treated with Low Dose Chemotherapy Concurrently with Fractionated Radiation

Dysphagia is a common consequence of chemotherapy and radiation treatment for oropharyngeal cancer. Injury is thought to occur due to damage to the muscle and/or nerves. This can severely impair swallowing function, leading to serious negative outcomes such as aspiration related pneumonia or tube feeding placement to maintain nutrition. Currently, there are only strategies to prevent swallowing dysfunction; however, the development of chronic radiation associated dysphagia persists effecting ~25% of head and neck cancer survivors. Therefore, there is a need to study the mechanisms associated with radiation associated dysphagia to help guide new treatments to improve swallowing outcomes. The present study investigated the effects of concurrent chemoradiation on swallowing function. We tested the hypothesis that fractionated radiation with low doses of chemotherapy alters swallowing kinematics and bolus transit compared to radiation alone or normal controls. We monitored the functional extent of chemoradiation or radiation treatment using videofluoroscopy swallow study in self feeding rats (n=16) at four weeks post treatment. Twelve rats underwent 48Gy of fractionated radiation to the submental muscles using a clinical linear accelerator given in 12 fractions of 4Gy. Irradiated rats received either cisplatin 1mg/kg or saline IP once per week for four weeks during radiation treatment. Four rats received no treatment. During videofluoroscopy, thin liquids and puree consistencies mixed with 40% w/v barium sulfate were given ad libitum. The movement trajectories of the tongue, mandible, and hyoid bone were quantitatively tracked from video data. Changes in the speed of the jaw and hyoid during swallowing were observed between treated and control rats. No differences were observed in bolus flow parameters i.e. pharyngeal transit speed, inter‐swallow interval, and swallow frequency between treatment groups. The average size of the bolus in vallecula decreased by ~4% prior to initiating pharyngeal swallow with chemoradiated rats (p < 0.05). Results suggest that low doses of chemotherapy in conjunction with radiation appear to have minimal differences in swallowing kinematics compared to radiation alone. Higher doses of chemotherapy may be needed to induce similar abnormalities in swallowing as seen clinically.

A computational framework for investigating bacteria transport in microvasculature

Blood-borne bacteria disseminate in tissue through microvasculature or capillaries. Capillary size, presence of red blood cells (RBCs), and bacteria motility affect bacteria intracapillary transport, an important yet largely unexplored phenomenon. Computational description of the system comprising interactions between plasma, RBCs, and motile bacteria in 5–10 diameter capillaries pose several challenges. The Immersed Boundary Method (IBM) was used to resolve the capillary, deformed RBCs, and bacteria. The challenge of disparate coupled time scales of flow and bacteria motion are reconciled by a temporal multiscale simulation method. Bacterium-wall and bacterium-RBC collisions were detected using a hierarchical contact- detection algorithm. Motile bacteria showed a net outward radial velocity of 2.8 µm/s compared to −0.5 µm/s inward for non-motile bacteria; thus, exhibiting a greater propensity to escape the bolus flow region between RBCs and marginate for potential extravasation, suggesting motility enhances extravasation of bacteria from capillaries.

Two dimensional computational model coupling myoarchitecture-based lingual tissue mechanics with liquid bolus flow during oropharyngeal swallowing

Biomechanical relationships involving lingual myoanatomy, contractility, and bolus movement are fundamental properties of human swallowing. To portray the relationship between lingual deformation and bolus flow during swallowing, a weakly one-way solid-fluid finite element model (FEM) was derived employing an elemental mesh aligned to magnetic resonance diffusional tractography (Q-space MRI, QSI) of the human tongue, an arbitrary Lagrangian-Eulerian (ALE) formulation with remeshing to account for the effects of lingual surface (boundary) deformation, an implementation of patterned fiber shortening, and a computational visualization of liquid bolus flow. Representing lingual tissue deformation in terms of its 2D principal Lagrangian strain in the mid-sagittal plane, we demonstrated that the swallow sequence was characterized by initial superior-anterior expansion directed towards the hard palate, followed by sequential, radially directed, contractions of the genioglossus and verticalis to promote lingual rotation (lateral perspective) and propulsive displacement. We specifically assessed local bolus velocity as a function of viscosity (perfect slip conditions) and observed that a low viscosity bolus (5 cP) exhibited maximal displacement, surface spreading and local velocity compared to medium (110 cP, 300 cP) and high (525 cP) viscosity boluses. Analysis of local nodal velocity revealed that all bolus viscosities exhibited a bi-phasic progression, with the low viscosity bolus being the most heterogeneous and fragmented and the high viscosity bolus being the most homogenous and cohesive. Intraoral bolus cohesion was depicted in terms of the distributed velocity gradient, with higher gradients being associated with increased shear rate and bolus fragmentation. Lastly, we made a sensitivity analysis on tongue stiffness and contractility by varying the degree of extracellular matrix (ECM) stiffness through effects on the Mooney-Rivlin derived passive matrix and by varying maximum tetanized isometric stress, and observed that a graded increase of ECM stiffness was associated with reduced bolus spreading, posterior displacement, and surface velocity gradients, whereas a reduction of global contractility resulted in a graded reduction of obtainable accommodation volume, absent bolus spreading, and loss of posterior displacement. We portray a unidirectionally coupled solid-liquid FEM which associates myoarchitecture-based lingual deformation with intra-oral bolus flow, and deduce that local elevation of the velocity gradient correlates with bolus fragmentation, a precondition believed to be associated with aspiration vulnerability during oropharyngeal swallowing.

The Utility of Functional Luminal Imaging Probes Measurements to Diagnose Dysmotility and Their Relationship to Impaired Bolus Clearance.

Functional luminal imaging probes (FLIP) have been used by multiple centers to assess esophagogastric junction (EGJ) function in patients at risk for esophageal obstruction but its role in diagnosing peristaltic disorders is less well studied. In particular, there are no studies comparing the sensitivity of FLIP to diagnose motility abnormalities and impaired bolus transit by high-resolution esophageal manometry with impedance. We prospectively recruited 42 patients undergoing high-resolution esophageal manometry with impedance (HRIM) who also underwent FLIP between 2018 and 2020. HRIM parameters were analyzed using Swallow Gateway software to determine peristaltic and lower esophageal sphincter pressure measurements as well as bolus flow parameters. FLIP tracings were analyzed for the presence of repetitive antegrade contractions (RACs), EGJ distensibility, and associated parameters. Forty-two patients were included (11 controls, 7 achalasia, 16 fundoplication, 8 dysmotility). The mean age of patients was 10.1 ± 0.9 years. There were significant differences in bolus flow parameters across diagnosis with longer bolus presence (BPT) in control patients compared with fundoplication and dysmotility patients. There was a significant correlation between EGJ diameter, EGJ distensibility and bolus flow time (BFT) for solid foods (r2 > 0.518, P < 0.02). The presence of RACs and EGJ relaxation during RACs was associated with a greater BFT and BPT across textures (P < 0.05). Forty-two percentage of patients with absent RACs, however, had clear peristalsis by HRIM. The presence of RACs and EGJ relaxation by FLIP correlate with improved bolus flow. Patients with an absence of RACs need HRIM to confirm any diagnoses of dysmotility.

Esophageal Bolus Domain Pressure and Peristalsis Associated With Experimental Induction of Esophagogastric Junction Outflow Obstruction.

Background/AimsIntrabolus pressures are important for esophageal bolus transport and may detect obstructed bolus flow. This study measured the effect esophageal outflow obstruction experimentally induce by a leg-lift protocol.MethodsTwenty-five gastroesophageal reflux disease patients referred for esophageal manometry and a normal motility diagnosis were included. Supine liquid swallows were tested. Leg-lift protocol generated esophageal outflow obstruction by increasing abdominal pressure. Esophageal pressure topography and intrabolus pressure metrics were calculated. These included, (1) mid-domain bolus distension pressure during esophageal emptying (DPE, mmHg) and (2) ramp pressure (mmHg/sec), generated by compression of the bolus between the peristaltic contraction and esophagogastric junction (EGJ).ResultsEGJ relaxation pressure was increased by leg-lift from 13 (11-17) to 19 (14-30) mmHg (P < 0.005) and distal contractile integral also increased from 1077 (883-1349) to 1620 (1268-2072) mmHg∙cm∙sec (P < 0.001) as a physiological response to obstruction. All bolus pressures were increased by leg lift; DPE increased from 17 (15-20) to 27 (19-32) mmHg (P < 0.001), and ramp pressure increased from 3 (1-4) to 5 (2-9) mmHg/sec (P < 0.05).ConclusionMeasuring pressures within the intrabolus domain can quantify changes related to obstruction to outflow and may serve as adjunct measures for confirming a diagnosis EGJ outflow obstruction.

Thin Liquid Bolus Volume Alters Pharyngeal Swallowing: Kinematic Analysis Using 3D Dynamic CT.

The previous studies reported that different volumes of thick liquid had an impact on spatiotemporal characteristics and pharyngeal response of swallowing. However, the bolus flow and swallowing motion pattern were different between thick and thin liquids. The effects of thin bolus volume on pharyngeal swallowing, especially true vocal cord (TVC) closure is still unclear. This study assessed the temporal characteristics when swallowing different volumes of thin liquid to determine the mechanical adaptation using 320-row area detector computed tomography (320-ADCT) and investigated a change of swallowing physiology including laryngeal closure, particularly TVC closure. Fourteen healthy women (28-45years) underwent 320-ADCT while swallowing of 3, 10, and 20ml of thin liquid barium in 45° semi-reclining position. Kinematic analysis was performed for each swallow including temporal characteristic, structural movements while swallowing, and maximal cross-sectional area of the upper esophageal sphincter (UES) opening. Bolus head reached to pharynx and esophagus earlier in larger volume significantly, indicating faster bolus transport as volume increased. There were significant effects on swallowing mechanism revealing earlier TVC closure and UES opening with increasing volume. Maximum cross-sectional area of the UES opening was increased to accommodate a larger bolus. Differences in mechanical adaptation through bolus transit and motion of swallowing structures were detected across increasing volumes. These volume-dependent adaptations potentially reduce the risk of aspiration. Understanding the swallowing physiological changes as volume increased is helpful for diagnosis and treatment of dysphagia patients as well as outcomes of swallowing rehabilitation in clinical practice.

Indication for the endoscopic treatment of Zenker’s diverticula

: Zenker’s diverticulum (ZD) is a false pulsion diverticulum located in Killian’s triangle. It accounts for about 70% of all esophageal diverticula. ZD incidence is uncommon, and it is mostly present in the elderly population. Although the pathophysiology has not been completely elucidated, an impaired relaxation of the cricopharyngeal muscle (CPM) has been identified as the leading mechanism. For this reason, the current therapeutic modalities are based on CPM myotomy to eliminate diverticular bolus retention, improve bolus flow, relieve outflow obstruction, and mitigate neuromotor impairment. The conventional open approach through a left cervicotomy has been mostly replaced by transoral techniques using either rigid endoscopy or flexible endoscopes. The minimally invasiveness of these techniques allows for reinterventions in case of recurrence. Endoscopic techniques present several advantages in terms of lower risk of adverse events, can be accomplished without the need for general anesthesia and neck hyperextension, and provide for a rapid patient recovery. The recent introduction of cutting-edge technology Z-POEM allows through a direct septal visualization for a complete myotomy, leading to a lower recurrence rate and higher symptoms resolution than endoscopic septotomy. The potential advantages also account for lower complication rates making it a promising technique.