Electromyography of Swallowing with Fine Wire Intramuscular Electrodes in Healthy Human: Amplitude Difference of Selected Hyoid Muscles

Impacts of body positions on the geniohyoid muscle contraction and swallowing difficulty in healthy adults

BACKGROUND

Body positions affect swallowing and gastroesophageal reflux. Swallowing impairment is one of the main causes of aspiration pneumonia. To prevent pneumonia, evaluation of body positions on gastroesophageal reflux recommended 30 degrees or higher semi-recumbent positions. The geniohypoid muscle and tongue play central roles in swallowing. However, the effects of body positions on contracting rates in the geniohyoid muscle and tongue pressure are unclear. Moreover, correlations between geniohyoid muscle contracting rates and subjective swallowing difficulties are unclear.

AIMS

This study aimed to identify the proper body positions on contracting rates in the geniohyoid muscle, tongue pressure, and subjective swallowing difficulties.

MATERIALS & METHODS

Twenty healthy adults swallowed 15- or 50 ml of water at 90 degrees sitting, 60- and 30 degrees semi-recumbent, and 0 degrees supine positions. We scored the subjective swallowing difficulties and measured the tongue pressure and the number of swallows. An ultrasound evaluated the geniohyoid muscle size and contracting rates.

RESULTS

At sitting and 60 degrees semi-recumbent positions, the geniohyoid muscle showed greter contracting rates than at 30 degrees semi-recumbent and supine postions (P < 0.05), which resulted in easier swalloiwng. Greater tongue pressure was weakly correlated with fewer swallows (r = -0.339, P = 0.002), whereas the body positions did not affect.

CONCLUSION

Considering swallowing and gastroesophageal reflux together, a trunk angle of 60 degrees or more might be beneficial for reducing the risk of aspiration.

Toward a robust swallowing detection for an implantable active artificial larynx: a survey

Total laryngectomy consists in the removal of the larynx and is intended as a curative treatment for laryngeal cancer, but it leaves the patient with no possibility to breathe, talk, and swallow normally anymore. A tracheostomy is created to restore breathing through the throat, but the aero-digestive tracts are permanently separated and the air no longer passes through the nasal tracts, which allowed filtration, warming, humidification, olfaction, and acceleration of the air for better tissue oxygenation. As for phonation restoration, various techniques allow the patient to talk again. The main one consists of a tracheo-esophageal valve prosthesis that makes the air passes from the esophagus to the pharynx, and makes the air vibrate to allow speech through articulation. Finally, swallowing is possible through the original tract as it is now isolated from the trachea. Yet, many methods exist to detect and assess a swallowing, but none is intended as a definitive restoration technique of the natural airway, which would permanently close the tracheostomy and avoid its adverse effects. In addition, these methods are non-invasive and lack detection accuracy. The feasibility of an effective early detection of swallowing would allow to further develop an implantable active artificial larynx and therefore restore the aero-digestive tracts. A previous attempt has been made on an artificial larynx implanted in 2012, but no active detection was included and the system was completely mechanic. This led to residues in the airway because of the imperfect sealing of the mechanism. An active swallowing detection coupled with indwelling measurements would thus likely add a significant reliability on such a system as it would allow to actively close an artificial larynx. So, after a brief explanation of the swallowing mechanism, this survey intends to first provide a detailed consideration of the anatomical region involved in swallowing, with a detection perspective. Second, the swallowing mechanism following total laryngectomy surgery is detailed. Third, the current non-invasive swallowing detection technique and their limitations are discussed. Finally, the previous points are explored with regard to the inherent requirements for the feasibility of an effective swallowing detection for an artificial larynx. Graphical Abstract.

Effects of Carbonated Water Concentration on Swallowing Function in Healthy Adults

In this study, we investigated the effects of carbonated water concentration on swallowing function using surface electromyography (sEMG). Healthy subjects (n = 52, 26.77 ± 3.21 years old) were asked to perform two swallows each of noncarbonated water, low-concentration carbonated water, medium-concentration carbonated water, and high-concentration carbonated water. Onset time, the mean sEMG activity amplitude, and duration of muscle activity in each swallow were measured and analyzed for orbicularis oris, masseter, submental muscle complex and infrahyoid muscles. Onset time significantly decreased and mean sEMG activity amplitude significantly increased with carbonation concentration. Therefore, stimulation with carbonation can be effective for modulating a faster and stronger swallow in the oral and pharyngeal phases of swallowing, and its effect on amplitude was greater in the oral phase than in the pharyngeal phase.Clinical Trials Registration This study is registered with Clinical Research Information Service (KCT0005925).

Noninvasive Evaluation of the Biomechanical Accommodations to Bolus Volume during Human Swallowing

Bolus volume is very important in the biomechanics of swallowing. By noninvasively characterizing swallow responses to volume challenges, we can gain more knowledge on swallowing and evaluate swallowing behavior easily. This study aimed to evaluate the impact of bolus volume on the biomechanical characteristics of oropharyngeal swallowing events with a noninvasive sensing system. Fifteen healthy male subjects were recruited and instructed to swallow 5, 10, and 15 ml of water. The sensing system consisted of a tongue pressure sensor sheet, bend sensor, surface electrodes, and a microphone. They were used to monitor tongue pressure, hyoid activity, surface EMG of swallowing-related muscles, and swallowing sound, respectively. In addition to the onset, the peak time and offset of the above four structures, certain characteristics, such as the duration, peak value, and interval of the structure motions, were measured during the different drinking tasks. The coordination between the hyoid movement and tongue pressure was also assessed. Although no sequence of the structural events changed with volume, most of the timings of the structural events were significantly delayed, except for certain hyoid activities. The swallowing volume did not affect the active durations of the monitored structures, the peak values, or intervals of tongue pressure and supra- and infrahyoid muscle activity, but certain hyoid kinetic phases were prolonged when a larger volume was swallowed. Additionally, sequential coordination between hyoid movement and tongue pressure was confirmed among the three volumes. These findings suggest that oropharyngeal structural movements change in response to bolus volume to facilitate safe swallowing. The noninvasive and quantitative measurements taken with the sensing system provide essential information for understanding normal oropharyngeal swallowing.

Pharyngolaryngeal semiology and prognostic factors in multiple system atrophy

Introduction

Multiple system atrophy (MSA) is a rare degenerative neurological disorder in adults. It induces parkinsonian and/or cerebellar syndrome associated with dysautonomia. Pharyngolaryngeal symptoms are common. Our aim is to describe the Pharyngolaryngeal semiology on one hand, and to ascertain whether the presence of these symptoms represents a prognostic factor for MSA on the other.

Methods

Thus, we carried out a retrospective, single-centre study, on a cohort receiving care at the centre of reference for MSA. The patients were referred for otorhinolaryngology assessment. The data was collected over the year 2020 with the help of computer software from the university hospital centre (UHC). Firstly, we described the Pharyngolaryngeal semiology specific to MSA by questioning patients, and by the results of nasofibroscopic examinations and swallowing tests. We then used multivariate analysis of variance to describe the prognostic factors of MSA progression (in UMSARS I and II points per month of progression) and survival (number of years between the first symptoms and death).

Results

This study included a hundred and one patients and made it possible to define a Pharyngolaryngeal semiology profile of MSA, which is: a reduction in laryngeal mobility (primarily vocal cord abduction defects), abnormal movements (particularly at rest or when initiating a movement) and a defect in the protection mechanisms of the upper airways. The swallowing difficulties are moderate and the main mechanisms are delayed pharyngeal swallow and/or an oro-pharyngeal transport defect. In the multivariate analyses, the contributing factors are laryngeal anomalies, modification of solid food to fluid food and nutritional complication.

Conclusion

ENT specialists should pay close attention to problems in the Pharyngolaryngeal dynamic and then consider a neurological cause. They can also itemize the clinical factors that could have a negative effect on the prognosis of the patient with MSA. Indeed, early detection makes it possible to provide care for respiratory and nutritional complications.

Effect of electromyography-triggered peripheral magnetic stimulation on voluntary swallow in healthy humans

BACKGROUND

Electrical stimulation therapy is effective for patients with dysphagia. However, because of the pain, strong stimulation cannot be applied. Although magnetic stimulation induces less pain, there are no reports on magnetic stimulation being synchronised with a swallowing reflex.

OBJECTIVE

This study aimed to determine whether it is possible to induce magnetic stimulation during a voluntary swallowing using electromyography (EMG)-triggered peripheral magnetic stimulation and to evaluate its effect on healthy individuals.

METHODS

A total of 20 healthy adults in seated position were instructed to swallow saliva and 10 ml of barium under videofluoroscopy. For concomitant use of magnetic stimulation, a magnetic stimulus for suprahyoid muscles at 30 Hz frequency was applied for 2 s when the EMG level in the sternohyoid muscle exceeded the threshold. During the voluntary swallowing, the movement of the hyoid bone and opening width of the upper oesophageal sphincter (UES) were measured. Furthermore, pressure topography was evaluated in 6 subjects using high-resolution manometry.

RESULTS

The magnetic stimulation significantly extended the movement time of the hyoid bone (p < 0.001). During liquid deglutition, significant increases were observed in the anterior maximum movement distance of the hyoid bone (p < 0.05), opening width of the UES (p < 0.001) and anterior movement distance of the hyoid bone at the maximum UES opening (p < 0.01). In the pressure topography, the maximum pressure immediately after UES closure significantly decreased with magnetic stimulation (p < 0.05).

CONCLUSION

EMG-triggered peripheral magnetic stimulation made it possible to apply magnetic stimulation during a voluntary swallowing.

Submandibular Push Exercise Using Visual Feedback from a Pressure Sensor in Patients with Swallowing Difficulties: A Pilot Study

Objectives: We aimed to determine the usefulness and effectiveness of a submandibular push exercise with visual feedback from a pressure sensor in patients with dysphagia through continuous exercise sessions. Methods: Twelve patients with dysphagia of various etiologies were included. A total of five exercise sessions (every 3 or 4 days) over three weeks were conducted. During the submandibular push exercise, patients were instructed to maintain a maximum force for 3 s, repeated for 1 min to measure the number of exercises, the maximum pressure, and the area of the pressure-time graph. We statistically compared the values of each exercise trial. Results: Among the 12 patients, eight completed the exercise sessions. As the number of exercise trials increased, the maximum pressure and the area in the pressure-time graph showed a significant increase compared to the previous attempt (p < 0.05). The maximum pressure and the area of the pressure-time graph improved from the first to the fourth session (p < 0.05). The values were maintained after the fourth session, and there was no significant difference between the fourth and the fifth exercise (p > 0.05). There was no significant difference between successful and non-successful groups, except for the Modified Barthel Index (p < 0.05). Conclusion: Through repetitive exercise training, the submandibular push exercise using visual feedback from a pressure sensor can be applied as an exercise method to strengthen swallowing related muscles, such as the suprahyoid and infrahyoid muscles. However, additional studies including more patients and a long-term study period are warranted to evaluate the effects of the exercise for improvement of dysphagia.

Evaluation of Swallowing Related Muscle Activity by Means of Concentric Ring Electrodes

Surface electromyography (sEMG) can be helpful for evaluating swallowing related muscle activity. Conventional recordings with disc electrodes suffer from significant crosstalk from adjacent muscles and electrode-to-muscle fiber orientation problems, while concentric ring electrodes (CREs) offer enhanced spatial selectivity and axial isotropy. The aim of this work was to evaluate CRE performance in sEMG recordings of the swallowing muscles. Bipolar recordings were taken from 21 healthy young volunteers when swallowing saliva, water and yogurt, first with a conventional disc and then with a CRE. The signals were characterized by the root-mean-square amplitude, signal-to-noise ratio, myopulse, zero-crossings, median frequency, bandwidth and bilateral muscle cross-correlations. The results showed that CREs have advantages in the sEMG analysis of swallowing muscles, including enhanced spatial selectivity and the associated reduction in crosstalk, the ability to pick up a wider range of EMG frequency components and easier electrode placement thanks to its radial symmetry. However, technical changes are recommended in the future to ensure that the lower CRE signal amplitude does not significantly affect its quality. CREs show great potential for improving the clinical monitoring and evaluation of swallowing muscle activity. Future work on pathological subjects will assess the possible advantages of CREs in dysphagia monitoring and diagnosis.

Effect of the submandibular push exercise using visual feedback from pressure sensor: an electromyography study

We developed a new exercise method called the submandibular push exercise that can strengthen the suprahyoid muscle by inducing only the motion of the hyoid bone without neck flexion. In this study, we aimed to investigate and compare the muscle activity of the suprahyoid and infrahyoid muscles in the course of performing three different swallowing exercises. Twenty healthy participants and fifteen patients with dysphagia were recruited. Each participant consecutively performed three exercises: Shaker, CTAR, and submandibular push exercises. To investigate muscle activation, surface electromyography was performed on the suprahyoid, infrahyoid, and SCM muscles, during the exercises. Root mean square (RMS) was measured. In healthy participants, the submandibular push exercise showed a significantly higher RMS value in the suprahyoid and infrahyoid muscles than the Shaker and CTAR exercises using repeated ANOVA with Tukey's post hoc test (p < 0.05). In patients with dysphagia, the submandibular push and Shaker exercises showed significantly higher RMS value in the suprahyoid and infrahyoid muscles than the CTAR exercise. However, no significant difference was found between the submandibular push and Shaker exercises. In both healthy and patients with dysphagia, the mean RMS values of the SCM muscles during the submandibular push exercise were significantly lower than those during the Shaker exercise using repeated ANOVA with Tukey's post hoc test (p < 0.05). In conclusion, considering the relatively superior selectiveness in suprahyoid and infrahyoid muscle contraction, the submandibular push exercise using visual feedback from pressure sensor could be an efficient supplementary exercise to the conventional swallowing muscle exercises. However, further studies may be necessary to confirm the improvement in swallowing difficulty.

A pilot study of modified resection for anterior floor of the mouth squamous cell carcinoma without infiltration of the mandible

OBJECTIVE

To explore the application of modified resection compared with traditional segmental resection of the mandible for patients with anterior floor of the mouth and tongue squamous cell carcinoma (SCC) without infiltration of the mandible.

SUBJECTS AND METHODS

This is a retrospective study including 36 eligible patients with anterior floor of the mouth SCC(9 patients received modified mandibulectomy, and 27 patients received segmental mandibulectomy).

RESULTS

No patients in the modified mandibulectomy group developed recurrence in the floor of the mouth, and all of the patients survived. Only one patient developed osteoradionecrosis. When the modified mandibulectomy group was compared with the segmental mandibulectomy group, the former exhibited a lower recurrence rate in the floor of the mouth (0.0% vs. 14.8%), less blood loss (516.7 ± 70.7 ml vs. 533.3 ± 93.0 ml), shorter durations of gastric tube placement (11.4 ± 4.5 days vs. 20.7 ± 11.9 days) and tracheostomy (6.9 ± 0.6 days vs. 8.5 ± 1.6 days), a lower postoperative infection rate (11.1% vs. 18.5%), and a shorter postoperative hospital stay (13.7 ± 3.8 days vs. 15.9 ± 5.1 days).

CONCLUSION

This modified mandibulectomy method is safe and feasible and is recommended for further prospective study in a clinical setting.

Dynamic Musculoskeletal Functional Morphology: Integrating diceCT and XROMM

The tradeoff between force and velocity in skeletal muscle is a fundamental constraint on vertebrate musculoskeletal design (form:function relationships). Understanding how and why different lineages address this biomechanical problem is an important goal of vertebrate musculoskeletal functional morphology. Our ability to answer questions about the different solutions to this tradeoff has been significantly improved by recent advances in techniques for quantifying musculoskeletal morphology and movement. Herein, we have three objectives: (1) review the morphological and physiological parameters that affect muscle function and how these parameters interact; (2) discuss the necessity of integrating morphological and physiological lines of evidence to understand muscle function and the new, high resolution imaging technologies that do so; and (3) present a method that integrates high spatiotemporal resolution motion capture (XROMM, including its corollary fluoromicrometry), high resolution soft tissue imaging (diceCT), and electromyography to study musculoskeletal dynamics in vivo. The method is demonstrated using a case study of in vivo primate hyolingual biomechanics during chewing and swallowing. A sensitivity analysis demonstrates that small deviations in reconstructed hyoid muscle attachment site location introduce an average error of 13.2% to in vivo muscle kinematics. The observed hyoid and muscle kinematics suggest that hyoid elevation is produced by multiple muscles and that fascicle rotation and tendon strain decouple fascicle strain from hyoid movement and whole muscle length. Lastly, we highlight current limitations of these techniques, some of which will likely soon be overcome through methodological improvements, and some of which are inherent. Anat Rec, 301:378-406, 2018. © 2018 Wiley Periodicals, Inc.

Animal Models for Dysphagia Studies: What Have We Learnt So Far

Research using animal models has contributed significantly to realizing the goal of understanding dysfunction and improving the care of patients who suffer from dysphagia. But why should other researchers and the clinicians who see patients day in and day out care about this work? Results from studies of animal models have the potential to change and grow how we think about dysphagia research and practice in general, well beyond applying specific results to human studies. Animal research provides two key contributions to our understanding of dysphagia. The first is a more complete characterization of the physiology of both normal and pathological swallow than is possible in human subjects. The second is suggesting of specific, physiological, targets for development and testing of treatment interventions to improve dysphagia outcomes.