Analysis of the Improvement Effect of Combined Application of Oral Rehabilitation Training and Neuromuscular Electrical Stimulation on Pediatric Swallowing Disorders

Pediatric swallowing disorders are common yet often overlooked neuro-muscular system diseases that significantly impact the quality of life and development of affected children. This study aims to explore the effect of combined application of oral rehabilitation training and neuromuscular electrical stimulation on improving pediatric swallowing disorders. Children meeting the inclusion criteria for swallowing disorders were divided into control and experimental groups based on different intervention protocols. The experimental group received combined oral rehabilitation training and neuromuscular electrical stimulation, while the control group received only oral rehabilitation training. Results showed that the intervention was more effective in the experimental group, with shorter recovery time for normal swallowing function and improved nutritional status and quality of life. This study provides scientific evidence for clinical treatment of pediatric swallowing disorders. In conclusion, the combined application of oral rehabilitation training and neuromuscular electrical stimulation effectively improves pediatric swallowing disorders, with superior efficacy compared to single treatment methods. Further research is needed to elucidate the mechanism of action and optimize treatment protocols to enhance the therapeutic outcomes and prognosis of pediatric swallowing disorders.

Differences in velopharyngeal pressures during speech sound production in patients with unilateral cleft lip and palate (UCLP) and healthy individuals

Background

During articulation the velopharynx needs to be opened and closed rapidly and a tight closure is needed. Based on the hypothesis that patients with cleft lip and palate (CLP) produce lower pressures in the velopharynx than healthy individuals, this study compared pressure profiles of the velopharyngeal closure during articulation of different sounds between healthy participants and patients with surgically closed unilateral CLP (UCLP) using high resolution manometry (HRM).

Materials and methods

Ten healthy adult volunteers (group 1: 20-25.5 years) and ten patients with a non-syndromic surgically reconstructed UCLP (group 2: 19.1-26.9 years) were included in this study. Pressure profiles during the articulation of four sounds (/i:/, /s/, /ʃ/ and /n/) were measured by HRM. Maximum, minimum and average pressures, time intervals as well as detection of a previously described 3-phase-model were compared.

Results

Both groups presented with similar pressure curves for each phoneme with regards to the phases described and pressure peaks, but differed in total pressures. An exception was noted for the sound /i:/, where a 3-phase-model could not be seen for most patients with UCLP. Differences in velopharynx pressures of 50% and more were found between the two groups. Maximum and average pressures in the production of the alveolar fricative reached statistical significance.

Conclusions

It can be concluded that velopharyngeal pressures of patients with UCLP are not sufficient to eliminate nasal resonance or turbulence during articulation, especially for more complex sounds. These results support a general understanding of hypernasality during speech implying a (relative) velopharyngeal insufficiency.

Modification of velopharyngeal closure pressures during phonation by neuromuscular electrical stimulation in healthy individuals

Introduction

Rhinophonia aperta may result from velopharyngeal insufficiency. Neuromuscular electrical stimulation (NMES) has been discussed in the context of muscle strengthening. The aim of this study was to evaluate in healthy subjects whether NMES can change the velopharyngeal closure pattern during phonation and increase muscle strength.

Method

Eleven healthy adult volunteers (21-57 years) were included. Pressure profiles were measured by high resolution manometry (HRM): isolated sustained articulation of /a/ over 5 s (protocol 1), isolated NMES applied to soft palate above motor threshold (protocol 2) and combined articulation with NMES (protocol 3). Mean activation pressures (MeanAct), maximum pressures (Max), Area under curve (AUC) and type of velum reactions were compared. A statistical comparison of mean values of protocol 1 versus protocol 3 was carried out using the Wilcoxon signed rank test. Ordinally scaled parameters were analyzed by cross table.

Results

MeanAct values measured: 17.15±20.69 mmHg (protocol 1), 34.59±25.75 mmHg (protocol 3) on average, Max: 37.86±49.17 mmHg (protocol 1), 87.24±59.53 mmHg (protocol 3) and AUC: 17.06±20.70 mmHg.s (protocol 1), 33.76±23.81 mmHg.s (protocol 3). Protocol 2 produced velum reactions on 32 occasions. These presented with MeanAct values of 13.58±12.40 mmHg, Max values of 56.14±53.14 mmHg and AUC values of 13.84±12.78 mmHg.s on average. Statistical analysis comparing protocol 1 and 3 showed more positive ranks for MeanAct, Max and AUC. This difference reached statistical significance (p=0.026) for maximum pressure values.

Conclusions

NMES in combination with articulation results in a change of the velopharyngeal closure pattern with a pressure increase of around 200% in healthy individuals. This might be of therapeutic benefit for patients with velopharyngeal insufficiency.

Impact of Varying Transcutaneous Electrical Stimulation Pulse Frequency on Swallow Timing Measures in Healthy Adults

The impaired swallow timing subsequent to dysphagia or aging can potentially endanger swallowing safety and efficiency. Preliminary evidence has suggested that transcutaneous electrical stimulation (TES) may have the potential to affect swallow timing. However, limited knowledge exists regarding which TES parameters can optimize swallow timing. Pulse frequency is one of the primary TES parameters that can affect the quality of muscle contraction. Yet, no clear information exists regarding how changing pulse frequency impacts the timing of swallowing events. This study aimed to investigate the varying effects of submental TES pulse frequency on swallowing events during and post-15-min TES administration. Twenty-six healthy individuals between the ages of 20 and 54 participated in this study and were assigned to high pulse frequency (HPF) (80 Hz) or low pulse frequency (LPF) (30 Hz) groups. Videofluoroscopic swallowing study (VFSS) was used to record swallowing. Three trials of 10 mL pureed mixed with barium sulfate were presented under three different conditions, including pre-TES, during TES, and post-TES, in which measures were taken following 15 min of TES delivery. The swallow timing events that were measured in each condition were time to maximum hyoid elevation, time to maximum laryngeal elevation, laryngeal vestibule closure reaction time (LVCrt), laryngeal vestibule closure duration (LVCd), time to maximum pharyngeal constriction, and pharyngoesophageal segment (PES) opening duration. No significant pulse frequency effect was found on any swallow timing measures during or after 15 min of TES. Both protocols decreased the duration of some swallowing events during TES including time to maximum hyoid elevation [p < 0.017, ηp2 = 0.185], LVCrt [p < 0.032, ηp2 = 0.158], and time to maximum pharyngeal constriction [p < 0.034, ηp2 = 0.155]. None of the significant TES effects were continued when TES ceased after 15 min. Overall, both protocols have comparable immediate effects on shortening the duration of some swallowing events during TES. Future clinical trials should examine whether these physiologic timing changes can lead to safer and more efficient swallows in patients with dysphagia.

Phonation-induced Upper Esophageal Sphincter Contraction Caused by Different Phonation Types

INTRODUCTION

The upper esophageal sphincter (UES) has been reported to show activity during phonation. As it is still unknown whether the phonation-induced UES contraction represents a reflex or a simultaneous activation phenomenon, i.e. co-innervation, this study aims to investigate and characterize the phonation-induced contraction of the UES in healthy individuals by analyzing the influence of various phonation tasks on pressure parameters of the UES.

METHODS

Twenty-five healthy volunteers produced the German neutral vowel [ə] in five different phonation tasks (modal voice, whispering, voiceless speech, creaky voice, and whispery voice). Simultaneously, they underwent high resolution manometry and electroglottography for measurement of pressure parameters in the region of the UES and latencies between larynx and UES activation.

RESULTS

During all types of phonation, the maximum pressures of the UES increased significantly (maximum pressure increases of 72%-132%). With regard to mean pressures this was valid for modal voice and whispering (mean pressure increases of 20%-25%). Differences concerning total pressure changes reached statistical significance when comparing whispering and voiceless speech as well as whispery voice. However, differences concerning the total pressure change between modal voices on the one hand and voiceless speech and whispery voice on the other hand turned out to be small. The averaged time delay between larynx and UES activation ranged from approximately -15 ms (whispery voice) to +15 ms (whispering).

CONCLUSION

A phonation induced pressure increase of the UES was confirmed in this study and did exist for different types of phonation. The extent of total pressure changes in the UES increases in relation with laryngeal muscle activity necessary for the phonation type. Next to varying effects of different types of phonation on UES activation, very short latencies indicate that a phonation induced contraction of the UES exists most likely due to co-innervation of UES and laryngeal muscles by the vagus nerve.

Applying High-Resolution Impedance Manometry for Detecting Swallowing Change in Anterior Cervical Spine Surgery Patients

Background

Objectively detecting perioperative swallowing changes is essential for differentiating the reporting of subjective trouble sensations in patients undergoing anterior cervical spine surgery (ACSS). Swallowing indicates the transmission of fluid boluses from the pharynx (velopharynx, oropharynx, and hypopharynx) through the upper esophageal sphincter (UES). Abnormal swallowing can reveal fluid accumulation at the pharynx, which increased the aspiration risk. However, objective evidence is limited. High-resolution impedance manometry (HRIM) was applied for an objective swallowing evaluation for a more detailed analysis. We aimed to elucidate whether HRIM can be used to detect perioperative swallowing changes in patients undergoing ACSS.

Methods

Fourteen patients undergoing elective ACSS underwent HRIM with the Dysphagia Short Questionnaire (DSQ, score: 0–18) preoperatively (PreOP), on postoperative at day 1 (POD1), and postoperative at day seven (POD7). We calculated hypopharyngeal and UES variables, including hypopharyngeal mean peak pressure (PeakP) and UES peak pressure, representing their contractility (normal range of PeakP, 69–280 mmHg; peak pressure, 149–548 mmHg). The velopharynx-to-tongue base contractile (VTI) was also calculated (normal range, 300–700 mmHg.s.cm), indicating contractility. The swallowing risk index (SRI) from HRIM combined with four hypopharyngeal parameters, including PeakP, represents the global swallowing function (normal range, 0–11). A higher SRI value indicated higher aspiration.

Results

SRI was significantly higher on POD1 (10.88 ± 5.69) than PreOP (6.06 ± 3.71) and POD7 (8.99 ± 4.64). In all patients, PeakP was significantly lower on POD1 (61.8 ± 18.0 mmHg) than PreOP (84.9 ±34.7 mmHg) and on POD7 (75.3 ± 23.4 mmHg). The UES peak pressure was significantly lower on POD1 (80.4 ± 30.0 mmHg) than PreOP (112.9 ± 49.3 mmHg) and on POD7 (105.6 ± 59.1 mmHg). Other variables, including VTI, did not change significantly among the three time points. DSQ scores were 1.36, 3.43, and 2.36 at PreOP, POD1, and POD7 respectively.

Conclusions

With similar trends in DSQ and SRI, swallowing was significantly decreased on POD1 because of decreased hypopharyngeal and UES contractility but recovered to the preoperative state on POD7 after ACSS. Applying HRIM is superior to DSQ in detecting mechanisms and monitoring the recovery from swallowing dysfunction.

Clinical Trial Registration

The study was registered at ClinicalTrials.gov (NCT03891940).

Electroceuticals in the Gastrointestinal Tract

The field of electroceuticals has attracted considerable attention over the past few decades as a novel therapeutic modality. The gastrointestinal (GI) tract (GIT) holds significant potential as a target for electroceuticals as the intersection of neural, endocrine, and immune systems. We review recent developments in electrical stimulation of various portions of the GIT (including esophagus, stomach, and small and large intestine) and nerves projecting to the GIT and supportive organs. This has been tested with varying degrees of success for several dysmotility, inflammatory, hormonal, and neurologic disorders. We outline a vision for the future of GI electroceuticals, building on advances in mechanistic understanding of GI physiology coupled with novel ingestible technologies. The next wave of electroceutical therapies will be minimally invasive and more targeted than current approaches, making them an indispensable tool in the clinical armamentarium.

Influence of Acid Swallows on the Dynamics of the Upper Esophageal Sphincter

Mechanisms of the upper esophageal sphincter (UES) when exposed to acid are still incompletely understood. The presented work investigated the reaction of the UES to acid exposure during swallowing. Ten healthy individuals swallowed ten 2 ml neutral water boli of pH 7, followed by 10 swallows each of different levels of acidity (pH 1.8, pH 3 and pH 5). Effects were analyzed by high-resolution manometry (HRM) for the primary parameter Restitution Time, as well as Resting Pressures, maximal, minimal pressures and time intervals. Restitution Times measured mean values of 12.67 s (SD ± 7.03 s) for pH 1.8, pH 7 = 8.69 s (SD ± 2.72 s), pH 3 = 7.56 s (SD ± 2.23 s) and pH 5 = 7.29 s (SD ± 2.55 s), showing prolonged Restitution Times in the UES when exposed to strong bolus acidity. This difference was significant towards the neutral bolus, but also to less acidic boli (pH 5: p = 0.006, pH 3: p = 0.009, pH 7: p = 0.038). Considerable differences of mean values were found for Post-Swallow Maximum and Period of Sphincter Activity. Also, Pre-Swallow Maximum values were found to be highest with the strongest acid. Relaxation Times showed a slight trend of prolongation for the highest bolus acidity. Prolonged Restitution Times may represent a reflexive protective mechanism triggered by receptors in the pharyngeal mucosa or the UES preventing regurgitation of acid into the pharynx and larynx, besides representing ongoing attempts of acid clearance. Exposure to high levels of acidity by a swallowed bolus does influence UES functions during swallowing.

Deglutition in Patients With Hypernasality Associated With Unilateral Cleft Lip and Palate Evaluated With High-Resolution Manometry

Objective:

To evaluate pharyngeal pressure profiles during swallowing in patients with unilateral cleft lip and palate (UCLP) and identify compensation mechanisms.

Design:

Prospective experimental study.

Setting:

University Hospital and Medical School.

Participants:

Ten volunteers and 10 patients with nonsyndromic repaired UCLP with hypernasality (age: 19-27 years, 5 females and 5 males per group) were included.

Interventions:

All participants swallowed 2 and 10 mL of water and underwent high-resolution manometry (HRM).

Main Outcome Measures:

Pharyngeal and upper esophageal sphincter (UES) parameters were measured using HRM. Student t test was used for statistical intergroup comparisons. Additionally, the Sydney Swallowing Questionnaire (SSQ) was used as a subjective measure.

Results:

Patients exhibited reduced velopharyngeal closing pressure and velopharyngeal and tongue base (TB) region contraction times, compared to volunteers ( P < .05). The UES opening and closing functions did not change. The SSQ revealed nasal regurgitation in some patients.

Conclusions:

In patients with UCLP, velopharyngeal region alterations are caused by impaired muscle force and function. The reduced TB contraction time may be a compensation mechanism allowing bolus transportation without nasal regurgitation. However, deglutition is not completely altered since UES function remains normal. Future studies will need to reveal at which point a decrease in velopharyngeal closing pressure will result in velopharyngeal insufficiency.

[High-resolution manometry of pharyngeal swallowing dynamics]

BACKGROUND

To transport a bolus from the mouth into the stomach, regular contraction of the pharyngeal muscles and a coordinated function of the upper esophageal sphincter (UES) are necessary. The muscle contraction generates intraluminal pressure, which pushes the bolus continuously forward. In contrast to imaging studies, manometric methods enable assessment of intraluminal pressure buildup and the function of the muscles involved. These methods were initially established for the esophagus and have been used increasingly in the pharynx for 7-8 years. Pharyngeal high-resolution manometry (pHRM) allows pressure measurements in high spatial and temporal resolution, and assessment of pharyngeal swallowing dynamics.

OBJECTIVE

An overview is given of the implementation, evaluation, and interpretation of the pHRM data, as well as of the current state of research.

MATERIALS AND METHODS

PubMed and Scopus were searched for the keywords "high-resolution manometry" and "pharynx" or "upper esophageal sphincter". Original articles, reviews, and book chapters on the subject pHRM were included.

RESULTS

Swallowing pressure conditions in the pharynx and the UES can be assessed by pHRM. The spatiotemporal pressure plot gives an overview of changes in pharyngeal motor function. Determination of swallowing parameters enables a sophisticated evaluation of swallowing; a comparison with normal values permits delimitation of pathologies.

CONCLUSION

Although several swallowing parameters still need to be further evaluated for clinical routine, a pHRM study should nowadays always be carried out for a comprehensive evaluation of the swallowing process.

Three-dimensional manometry of the upper esophageal sphincter in swallowing and nonswallowing tasks

Objectives/Hypothesis

High‐resolution manometry (HRM) is useful in identifying disordered swallowing patterns and quantifying pharyngeal and upper esophageal sphincter (UES) physiology. HRM is limited by unidirectional sensors and circumferential averaging of pressures, resulting in an imperfect understanding of pressure from asymmetrical pharyngeal anatomy. This study aims to evaluate UES pressures simultaneously from different axial directions.

Study Design

Case series.

Methods

Three‐dimensional HRM was performed on eight healthy subjects to evaluate circumferential UES pressure patterns at rest, during the Valsalva maneuver, and during water swallowing.

Results

Multivariate analysis of the variance revealed a significant main effect of circumferential direction on pressure while at rest (P < .001); pressure was greater in the anterior and posterior portions of the UES versus lateral portions. A significant main effect of direction on pressure was not found during the Valsalva maneuver. During swallowing of a 5‐mL water bolus, circumferential direction had a significant main effect on pressure immediately before UES pressure dropped (P = .001), while the UES was open (P = .01) and at UES closure (P < .001). There was also a significant main effect of sensor level along the vertical axis on pressure immediately before UES pressure dropped (P = .032) and at UES closure (P < .001). Anterior and posterior pressures were again greater than lateral pressures at all swallowing events.

Conclusions

These results confirm that UES pressures vary significantly based on their circumferential origin, with the majority of the total pressure generated in anterior and posterior regions. Improved understanding of UES pressure in a three‐dimensional space can lead to more sophisticated treatments for pharyngeal and UES dysfunction.

Level of Evidence

4. Laryngoscope, 126:2539–2545, 2016

Oropharyngeal dysphagia: manifestations and diagnosis

Swallowing disorders (dysphagia) have been recognized by the WHO as a medical disability associated with increased morbidity, mortality and costs of care. With increasing survival rates and ageing of the population, swallowing disorders and their role in causing pulmonary and nutritional pathologies are becoming exceedingly important. Over the past two decades, the study of oropharyngeal dysphagia has been approached from various disciplines with considerable progress in understanding its pathophysiology. This Review describes the most frequent manifestations of oropharyngeal dysphagia and the clinical as well as instrumental techniques that are available to diagnose patients with dysphagia. However, the clinical value of these diagnostic tests and their sensitivity to predict outcomes is limited. Despite considerable clinical research efforts, conventional diagnostic methods for oropharyngeal dysphagia have limited proven accuracy in predicting aspiration and respiratory disease. We contend that incorporation of measurable objective assessments into clinical diagnosis is needed and might be key in developing novel therapeutic strategies.

[Physiology of the upper esophageal sphincter]

The upper esophageal sphincter (UES) forms a barrier between the pharynx and the esophagus. When opened, the UES allows the food bolus to pass into the esophagus, as well as permitting emesis and eructation. The basal sphincter tone constitutes a barrier function which serves to prevent reflux and passive aerophagia in the case of deep breathing. Basal sphincter tone is dependent on several influencing factors; during swallowing, sphincter opening and closure follow a complex multiphase pattern. This article presents an overview of the current understanding of UES physiology.