Submental sEMG and hyoid movement during Mendelsohn maneuver, effortful swallow, and expiratory muscle strength training

Orofacial and cervical myofunctional intervention programmes for older adults: A scoping review

INTRODUCTION

Senescent stomatognathic systems undergo anatomical changes that are not always compensated by physiology due to associated factors such as poorly fitted dentures, dental changes, and clinical conditions that trigger sarcopenia. When these conditions are not properly addressed, they can lead to nutritional deficiencies. Hence, this study aimed to map orofacial and cervical myofunctional intervention programmes for older adults, evaluate the current research in this area, and formulate suggestions for further investigation.

METHODS

Scoping review is based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews checklist. The EMBASE, LILACS, PubMed/Medline, Scopus, Web of Science, and grey literature databases were systematically searched. Studies addressing therapeutic programmes, myofunctional exercises, and their influence on the stomatognathic system of older adults were included. Studies with populations younger than 60 years, residing in long-term care facilities, homes, or hospital care, and with associated comorbidities were excluded, as well as secondary studies.

RESULTS

A total of 3098 studies were retrieved. After applying the eligibility criteria, nine studies were eligible for this review. The nine studies were published in English between 2008 and 2021 in the United States, Japan, and South Korea. The participants' mean ages ranged from 64 to 81 years, with a preponderance of females. Six of the studies divided the sample into intervention and control groups. Two studies referred to programmes to promote oral function through facial expression and tongue muscle exercises, salivary gland massage, and swallowing biomechanics. Seven studies report the positive influence of myofunctional exercises on the stomatognathic system.

CONCLUSION

The mapping concluded that therapeutic programmes, including educational actions, help prevent orofacial myofunctional disorders, and improve the functionality of the stomatognathic system.

Effortful Swallow Maneuver and Modifications on Swallow Dynamics in Healthy Adults

INTRODUCTION

Effortful swallow (ES) is a widely used technique in dysphagia management, believed to strengthen oropharyngeal muscles and enhance swallowing safety and efficiency. Although its impact on the oral phase of swallowing is well documented, its effects on pharyngeal swallowing physiology remain inconsistent. This study aimed to elucidate the effects of ES on swallowing kinematics and timing, addressing existing inconsistencies in the literature.

METHODS

This study involved 22 healthy adults using archived videofluoroscopic swallowing studies. Participants performed three swallow trials of 10 mL puree under regular conditions and with the ES maneuver. The outcome measures comprised swallow timing and kinematic measures. Swallow timing parameters included time to maximum hyoid and laryngeal excursion, laryngeal vestibule closure (LVC) reaction and duration, pharyngeal constriction duration, pharyngoesophageal segment (PES) opening duration, and swallow duration. Swallow kinematic parameters encompassed hyoid and laryngeal excursions, pharyngeal constriction ratio, and maximum PES width. All variables were analyzed via videofluoroscopy. Paired t tests were used to examine the effect of ES on each outcome measure, with a significance threshold set at p < 0.004.

RESULTS

The ES maneuver significantly increased the duration of LVC, pharyngeal constriction, PES opening, and overall swallow duration. It also improved the pharyngeal constriction ratio. However, there were no significant changes in hyoid and laryngeal excursions. Submental muscle activity showed a notable increase during ES.

CONCLUSION

The study demonstrates that ES can effectively modify certain temporal and kinematic aspects of swallowing, particularly by prolonging key phases and enhancing pharyngeal constriction. These findings suggest the potential utility of ES in dysphagia rehabilitation, especially in cases that require prolonged pharyngeal constriction, LVC, and PES opening. However, the limited impact on hyoid and laryngeal excursions along with LVC reaction time indicates that ES may not address all aspects of dysphagia. The findings highlight the need for tailored therapeutic approaches in dysphagia management, considering individual physiological impairment profiles.

Evaluating Anterior and Posterior Oral Tongue Contributions to Pressure Generation: A Comparison Between Regular and Effortful Saliva Swallows

PURPOSE

This study determined the contributions of the anterior and posterior tongue regions in tongue pressure generation during regular saliva swallows (SSs) and effortful swallows (ESs) completed under two different instructions. The association between tongue pressure and perceived effort to swallow was also examined.

METHOD

Forty healthy adults without swallowing disorders participated in this study, divided into two age groups: 20 younger (Mage = 21.95 years, SD = 4.43) and 20 older (Mage = 70.10 years, SD = 4.30). Simultaneous data acquisition involved submental surface electromyography, tongue manometry, and a visual analog scale across swallowing conditions (SS, ES with tongue emphasis, and ES with pharyngeal squeezing). The main outcome measures were tongue pressure during swallowing and perceived effort to swallow.

RESULTS

Overall tongue pressure during ESs with tongue emphasis and with pharyngeal squeezing was greater than that during SSs (R2 = .78, p < .001). Moreover, tongue pressure during the ES with tongue emphasis was greater than that during the ES with pharyngeal squeezing (t = 25.63, p < .001). The posterior tongue region generated more pressure during SSs (R2 = .64, p < .001) and the ES with tongue emphasis (R2 = .55, p < .001) than the anterior tongue. Finally, a positive correlation was found between perceived effort and tongue pressure during swallowing (r = .75, 95% CI [0.72, 0.77]).

CONCLUSIONS

Tongue pressure generation was affected by the type of instruction used to elicit ESs, and the posterior tongue showed relatively greater pressure contributions than the anterior tongue for ESs with tongue emphasis and SSs. Furthermore, age-related declines in pressure generation during swallowing were not evidenced in this study, underscoring the ability of healthy older individuals to appropriately modulate lingual pressure during ESs. Last, our results showed that the visual analog scale is a simple tool for rating swallowing effort during ESs, supporting its potential clinical use to train ESs.

Concurrent Validity of a Low-Cost Manometer for Objective Assessments of Respiratory Muscle Strength

OBJECTIVE(S)

This study examined the agreement in maximal expiratory (MEP) and inspiratory (MIP) pressure readings between two digital manometers: (1) the MicroRPM - the gold-standard manometer for respiratory muscle strength testing; and (2) the LDM - a low-cost, commercially available, alternative manometer.

METHODS

Positive (MEP) and negative (MIP) pressures were simultaneously applied to the MicroRPM and LDM using a 3-liter syringe within a controlled laboratory setting. Pressure readings were compared, and agreement was analyzed using Lin's concordance correlation (ρc ). Agreement was interpreted as 'poor' if <0.90, 'moderate' if 0.90 - <0.95, 'substantial' if 0.95 - <0.99, and 'excellent' if ≥0.99. Twenty percent of the pressure trials were repeated by a second researcher to examine test-retest reliability.

RESULTS

A total of 150 trials were completed, ranging from -167 to +208 cmH2 O. There was a median absolute difference of 0.3 cmH2 O in pressure readings between the MicroRPM and the LDM. Lin's concordance correlation revealed 'excellent' agreement between the LDM and MicroRPM devices, with test-retest reliability assessment revealing 'substantial-to-excellent' agreement between the LDM and MicroRPM devices, with a concordance correlation coefficient of ρc  = 0.999 (95% CI: 0.999-0.999).

CONCLUSIONS

There was a median difference of 1.0% in MEP and MIP pressure readings consistently observed between the LDM and MicroRPM. Despite these relatively small differences, excellent agreement between the two manometers was present. These data suggest the LDM may be a valid, lower cost alternative to the MicroRPM for objectively assessing respiratory strength in clinical practice; however, additional research is needed in healthy adults and in patient populations.

LEVEL OF EVIDENCE

NA Laryngoscope, 134:1831-1836, 2024.

Surface Electromyographic Activity of the Masseter Muscle During Regular and Effortful Saliva Swallows: A Preliminary Study

Biofeedback is a critical component in motor learning of new, complex behaviors such as modifications to swallowing. Surface electromyography (sEMG) is a commonly employed biofeedback tool in swallowing management to assess muscle activity patterns, determine amplitude and duration of swallowing, and train swallowing strategies such as the effortful swallow (EFS) maneuver. The EFS can potentially change multiple physiological components of the swallowing process such as pressure generation and movement of biomechanical structures. The purposes of this study were to determine whether the masseter muscle could differentiate a normal swallow (NS) from an EFS and whether there was a relationship between perceived muscle effort used to swallow and objective measures of muscle activity. Twenty healthy young adults participated in this study. Masseter sEMG peak amplitude and duration were measured across five regular saliva swallows and five effortful saliva swallows. Additionally, participants rated their perceived swallowing effort using a visual analog scale (VAS). Two swallowing conditions, NSs and EFSs were compared with hierarchical models, and repeated measures correlation was used to determine the relationships between the VAS and sEMG peak amplitude. Participants produced swallows with greater masseter sEMG peak amplitude and duration during the EFS. Moreover, a positive correlation was identified between perceived swallowing effort and masseter sEMG peak amplitude. These findings support the potential use of the masseter muscle to differentiate NSs from EFSs and implement the VAS during therapy for tracking patients' performance, particularly in settings with limited access to sEMG.

Swallowing kinematics and submental muscles activation during a newly designed maneuver called Mouth Open Swallowing Maneuver: A comparative study

The aim of this study was to design a new maneuver called the Mouth Open Swallowing Maneuver (MOSM), and to compare swallowing kinematics and submental muscles activation (SMA) between MOSM and two current approaches used in dysphagia rehabilitation. Fifty healthy volunteers were asked to perform three repetitions of dry swallowing (DS) (control task), the MOSM, the Mendelsohn Maneuver (MM), and the Tongue-Hold Maneuver (THM) during videofluoroscopic swallowing study accompanied with simultaneous SMA recording. Swallowing kinematics were measured by frame-by-frame analysis on hyolaryngeal movement using ImageJ. Swallowing with maximum hyolaryngeal movement and SMA during these tasks was used for comparative analysis. Vertical movement of the hyoid during the MOSM was significantly greater than those observed during the DS and the THM (p<0.001, p<0.001). Horizontal movement of the hyoid during DS and the THM was significantly greater than that observed during the MM (p = 0.001, p = 0.001). Vertical movement of the larynx during the MOSM was significantly greater than those observed during DS, MM, and THM (p<0.001). There was no significant difference between tasks in horizontal movement of the larynx (p = 0.785). SMA during the THM was significantly greater than that observed during MOSM (p = 0.002). No significant difference was found between other tasks in terms of SMA (p>0.05). The MOSM as a newly designed maneuver was significantly superior to other maneuvers in increasing vertical hyolaryngeal movement. The THM has as much effect on hyolaryngeal movement as the MM. In this study, the MOSM was shown to be effective in increasing hyolaryngeal movement. ClinicalTrials.gov Protocol Registration and Results System (PRS); the clinical trial registration number (NCT05579041).

Cough and Swallowing Therapy and Their Effects on Vocal Fold Bowing and Laryngeal Lesions

OBJECTIVE

Expiratory muscle strength training (EMST) and sensorimotor training of airway protection (smTAP) are two exercises intended to improve cough and swallowing in people with Parkinson's Disease (PwPD). The aims of this study were to (1) examine whether EMST or smTAP elicit changes to vocal fold bowing; and (2) describe the safety of EMST and smTAP as it relates to the development of vocal fold lesions.

METHOD(S)

This was a secondary analysis of data from PwPD who completed EMST or smTAP as part of a prospective randomized controlled trial. Vocal fold bowing (BI) and the presence of laryngeal lesions were blindly analyzed from flexible endoscopic evaluation of swallowing (FEES) using ImageJ software and operational definitions. Linear regression was used to examine the influence time (pre- vs. post-therapy) and therapy (EMST vs. smTAP) on vocal fold bowing. Descriptive statistics were used to describe the presence of laryngeal lesions.

RESULT(S)

Overall, 56 participants were included, 28 per group. The median BI scores pre- and post-therapy were 8.2% and 8.3% for the EMST group and 11.3% and 8.4% for the smTAP group, respectively. Statistical analyses revealed insufficient evidence to suggest an effect of time and treatment type on BI (p > 0.05) or on the presence of vocal fold lesions (p > 0.05).

CONCLUSION

Based on these and previous findings, it appears that changes in vocal fold bowing do not drive treatment effects following EMST and smTAP. Also, this study further supports the safety of smTAP and EMST despite the required forceful exhalation and repetitive coughing.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1127-1132, 2024.

Improvement in Swallowing Function in Patients with Previous Irradiation for Nasopharyngeal Carcinoma by Expiratory Muscle Strength Training

Dysphagia and chronic aspiration are common post-irradiation complications in nasopharyngeal carcinoma (NPC) survivors. Expiratory Muscle Strength Training (EMST) is a simple device-driven exercise therapy for swallowing training. This study investigates the effectiveness of EMST in a group of post-irradiated NPC patients. This prospective cohort, including twelve patients with previous irradiation for NPC and with swallowing disturbance, was performed between 2019 and 2021 in a single institution. Patients were trained with EMST for 8 weeks. Non-parametric analyses examined effects of EMST on primary outcome, maximum expiratory pressure. Secondary outcomes were measured with Penetration-aspiration scale, Yale pharyngeal residue severity rating scale (YPRSRS) by flexible endoscopic evaluation of swallowing, and Eating Assessment Tool (EAT-10) and M.D. Anderson Dysphagia Inventory questionnaire. Twelve patients, with a mean (SD) age of 64.3 (8.2) were recruited. There was no patient dropout with 88.9% overall compliance of training. Maximum expiratory pressure improved by 41% (median 94.5 to 133.5 cmH2O, p = 0.003). There was reduction in Penetration-aspiration scale with thin liquid (median 4 to 3, p = 0.026), and in YPRSRS at pyriform fossa with mildly thick liquid (p = 0.021) and at vallecula with thin liquid (p = 0.034), mildly thick liquid (p = 0.014) and pureed meat congee (p = 0.016). Questionnaire scores did not significantly change statistically. EMST is an easy-to-use and effective exercise therapy to improve airway safety and swallowing function in post-irradiated NPC survivors.

Hyolaryngeal Movement During Normal and Effortful Swallows Determined During Ultrasonography

PURPOSE

This study investigated (a) the effects of the effortful swallow under two different instructions (tongue emphasis vs. pharyngeal squeezing) on hyoid displacement and hyoid-larynx approximation, (b) the association between tongue pressure and hyolaryngeal movement during normal swallowing and the effortful swallow produced with tongue emphasis, and (c) age-related differences in hyolaryngeal movement during normal and effortful swallows (tongue emphasis vs. pharyngeal squeezing) in healthy individuals.

METHOD

Forty healthy adults (20 younger and 20 older) swallowed their saliva as they normally do (normal swallow) and performed the effortful swallow with tongue emphasis and pharyngeal squeezing. Tongue-to-palate pressure during swallowing was measured using the Iowa Oral Performance Instrument, hyolaryngeal movement was measured using ultrasonography, and submental surface electromyography was used to track swallows.

RESULTS

Results revealed differences in hyolaryngeal movement across swallowing types. Both types of effortful swallows showed greater hyolaryngeal movement than normal swallows. Additionally, hyolaryngeal movement was greater during the effortful swallow with tongue emphasis than the effortful swallow with pharyngeal squeezing. Age-related differences were found only in hyoid-larynx approximation during the effortful swallow with tongue emphasis (younger > older adults). Furthermore, moderate positive correlations were identified between tongue pressure and hyolaryngeal movement during normal swallows and the effortful swallow with tongue emphasis.

CONCLUSIONS

The findings show that varying instructions of the effortful swallow affect hyolaryngeal movement differently, suggesting that clinicians may need to individualize the effortful swallow instruction according to the physiological impairments of each patient. Additionally, natural age-related changes in swallowing physiology do not seem to affect an individual's ability to perform the effortful swallow or to impact hyolaryngeal movement. Finally, the association between tongue pressure and hyolaryngeal movement during normal swallows and the effortful swallow with tongue emphasis suggests that the tongue plays a critical role in swallowing, priming subsequent swallowing events.

Effectiveness of Home-Based Telerehabilitation Interventions for Dysphagia in Patients With Head and Neck Cancer: Systematic Review

BACKGROUND

Multimodal treatment-induced dysphagia has serious negative effects on survivors of head and neck cancer. Owing to advances in communication technologies, several studies have applied telecommunication-based interventions that incorporate swallowing exercises, education, monitoring, feedback, self-management, and communication. It is especially urgent to implement home-based remote rehabilitation in the context of the COVID-19 pandemic. However, the optimal strategy and effectiveness of remote interventions are unclear.

OBJECTIVE

This systematic review aimed to examine the evidence regarding the efficacy of telerehabilitation for reducing physiological and functional impairments related to swallowing and for improving adherence and related influencing factors among head and neck cancer survivors.

METHODS

The PubMed, MEDLINE, CINAHL, Embase, and Cochrane Library databases were systematically searched up to July 2023 to identify relevant articles. In total, 2 investigators independently extracted the data and assessed the methodological quality of the included studies using the quality assessment tool of the Joanna Briggs Institute.

RESULTS

A total of 1465 articles were initially identified; ultimately, 13 (0.89%) were included in the systematic review. The quality assessment indicated that the included studies were of moderate to good quality. The results showed that home-based telerehabilitation improved the safety of swallowing and oral feeding, nutritional status, and swallowing-related quality of life; reduced negative emotions; improved swallowing rehabilitation adherence; was rated by participants as highly satisfactory and supportive; and was cost-effective. In addition, this review investigated factors that influenced the efficacy of telerehabilitation, which included striking a balance among swallowing training strategy, intensity, frequency, duration, and individual motor ability; treating side effects of radiotherapy; providing access to medical, motivational, and educational information; providing feedback on training; providing communication and support from speech pathologists, families, and other survivors; and addressing technical problems.

CONCLUSIONS

Home-based telerehabilitation has shown great potential in reducing the safety risks of swallowing and oral feeding, improving quality of life and adherence, and meeting information needs for dysphagia among survivors of head and neck cancer. However, this review highlights limitations in the current literature, and the current research is in its infancy. In addition, owing to the diversity of patient sociodemographic, medical, physiological and functional swallowing, and behavioral factors, we recommend the development of tailored telemedicine interventions to achieve the best rehabilitation effects with the fewest and most precise interventions.

Dosages of swallowing exercises in stroke rehabilitation: a systematic review

PURPOSE

To investigate the dosages of swallowing exercises reported in intervention studies on post-stroke dysphagia through systematic review.

METHODS

Five electronic databases were searched from inception until February 2022 with reference tracing of included studies. Studies were included, where adults with post-stroke dysphagia received rehabilitative, behavioural swallowing exercises, pre/post outcomes were reported, and intervention dosage was described in detail, including frequency, intensity, time, and type of exercise. Two reviewers independently screened studies and rated quality using ASHA Levels of Evidence tool. Data was tabulated and narratively described.

RESULTS

54 studies were included with a total 1501 participants. Studies included 28 randomised controlled trials, 8 non-randomised controlled trials, 12 pre/post studies, 3 retrospective case controls and 3 case studies. Results showed inconsistent reporting of intervention dosage, with intensity the least consistently reported dosage component. While swallowing intervention was most commonly provided five times per week for four weeks, there was a wide breadth of type, frequency, intensity and duration of swallowing exercises reported. Dosage under-reporting and variation was particularly observed in "standard care" co-interventions or control groups. Study strengths included following PRISMA guidelines, providing a comprehensive review of swallowing exercise methodology and dosages, and including non-English studies. The limitation was lack of meta-analysis due to the heterogeneity of included studies.

CONCLUSIONS

Dosages of swallowing exercises are inconsistently reported and vary significantly in post-stroke dysphagia studies. Results indicate the need for consistent and comprehensive dosage reporting in dysphagia studies, and for further research into evidence-based principles to optimise swallowing exercise dosages.

SYSTEMATIC REVIEW REGISTRATION NUMBER

131294.

Links Between Swallowing and Consciousness: A Narrative Review

This literature review explores a wide range of themes addressing the links between swallowing and consciousness. Signs of consciousness are historically based on the principle of differentiating reflexive from volitional behaviors. We show that the sequencing of the components of swallowing falls on a continuum of voluntary to reflex behaviors and we describe several types of volitional and non-volitional swallowing tasks. The frequency, speed of initiation of the swallowing reflex, efficacy of the pharyngeal phase of swallowing and coordination between respiration and swallowing are influenced by the level of consciousness during non-pathological modifications of consciousness such as sleep and general anesthesia. In patients with severe brain injury, the level of consciousness is associated with several components related to swallowing, such as the possibility of extubation, risk of pneumonia, type of feeding or components directly related to swallowing such as oral or pharyngeal abnormalities. Based on our theoretical and empirical analysis, the efficacy of the oral phase and the ability to receive exclusive oral feeding seem to be the most robust signs of consciousness related to swallowing in patients with disorders of consciousness. Components of the pharyngeal phase (in terms of abilities of saliva management) and evoked cough may be influenced by consciousness, but further studies are necessary to determine if they constitute signs of consciousness as such or only cortically mediated behaviors. This review also highlights the critical lack of tools and techniques to assess and treat dysphagia in patients with disorders of consciousness.

The Effects of Tongue Elevation using a Weighted Plastic Bottle on the Tongue Pressure and Activity of Suprahyoid Muscles

BACKGROUND

A rise in tongue pressure coincides with an increase in the suprahyoid muscles activity.

OBJECTIVES

The aim was to investigate the effects of holding a weighted plastic bottle on tongue pressure and the suprahyoid muscles activity.

METHODS

Eighteen participants (8 men and 10 women; mean age 42 ± 16 years) participated in this study. All participants had no history of speech, language, hearing, or swallowing disorders and no tooth loss, and they did not require dentures. Healthy participants held gauzes connected with a plastic bottle with increasing resistive loads of 0 g, 250 g, 500 g, and 750 g, between their palate and tongue. The maximum tongue pressure and average tongue pressure were measured during a 5-second hold. The average tongue pressure was defined as the mean tongue-pressure data in each task. The suprahyoid muscles activity was measured using the electromyogram (EMG). The root mean square of the EMG signals measured while lifting different loads and while performing the head lifting exercises were compared. All variables were examined using the Friedman's test and Wilcoxon signed-rank test.

RESULTS

The maximum tongue pressure (p < .05) and average tongue pressure values (p < .05) increased gradually in the anterior-median region with increasing resistive loads, and the root mean square amplitudes for 250 g, 500 g, and 750 g were not significant compared to head lifting exercises.

CONCLUSION

These results indicated that Plastic bottle holding could be a potential strength-training tool for the tongue and the suprahyoid muscles.

Effects of Respiratory Muscle Strength Training on Respiratory-Related Impairments of Parkinson's Disease

In addition to typical motor dysfunction, Parkinson's disease is also characterized by respiratory-related dysfunction. As a means of rehabilitation, respiratory muscle strength training (RMST) has been applied to restore Parkinson's disease (PD) functions. However, the current clinical value of RMST in the application for PD has not been widely established. This article aims to review the research progress of the application of RMST in PD rehabilitation to provide new sight into respiratory-related impairments management in people with PD.

Adherence to Home-Based Swallowing Therapy Using a Mobile System in Head and Neck Cancer Survivors

Purpose A large knowledge gap related to dysphagia treatment adherence was identified by a recent systematic review: Few existing studies report on adherence, and current adherence tracking relies heavily on patient self-report. This study aimed to report weekly adherence and dysphagia-specific quality of life following home-based swallowing therapy in head and neck cancer (HNC). Method This was a quasi-experimental pretest-posttest design. Patients who were at least 3 months post-HNC treatment were enrolled in swallowing therapy using a mobile health (mHealth) swallowing system equipped with surface electromyography (sEMG) biofeedback. Participants completed a home dysphagia exercise program across 6 weeks, with a target of 72 swallows per day split between three different exercise types. Adherence was calculated as percent trials completed of trials prescribed. The M. D. Anderson Dysphagia Inventory (MDADI) was administered before and after therapy. Results Twenty participants (75% male), with an average age of 61.9 years (SD = 8.5), completed the study. The majority had surgery ± adjuvant (chemo)radiation therapy for oral (10%), oropharyngeal (80%), or other (10%) cancers. Using an intention-to-treat analysis, adherence to the exercise regimen remained high from 84% in Week 1 to 72% in Week 6. Radiation therapy, time since cancer treatment, medical difficulties, and technical difficulties were all found to be predictive of poorer adherence at Week 6. A statistically significant improvement was found for composite, emotional, and physical MDADI subscales. Conclusions When using an mHealth system with sEMG biofeedback, adherence rates to home-based swallowing exercise remained at or above 72% over a 6-week treatment period. Dysphagia-specific quality of life improved following this 6-week treatment program.

A comparison of swallow-related submandibular contraction amplitude and duration in people with Parkinson's disease and healthy controls

PURPOSE

To compare the contraction amplitude and contraction duration of submandibular muscles during the pharyngeal stage of swallowing in people with Parkinson's disease (PD) compared to normal controls.

METHOD

A prospective cross-sectional study design was utilised to recruit 24 participants from the regional area. A total of 14 people with PD and 10 healthy controls (HC) were recruited. Participants swallowed three volumes of thin liquid (5mL, 10mL, 15mL) while the activity of the submandibular muscles was recorded using surface electromyography. Measurements of contraction amplitude ratio (normalised to a maximum voluntary contraction) and contraction duration were computed from recorded electromyographic signals. Receiver Operating Characteristics (ROC) were computed for variables associated with significant main effects.

RESULT

Analyses revealed a significant effect of group on contraction amplitude ratio but not contraction duration. There were no significant effects of bolus volume on the dependent variables. ROC analysis indicated that contraction amplitude ratio accurately predicted group assignment in 77% cases.

CONCLUSION

Findings revealed that a majority of people with PD in this study utilised a greater percentage of their maximum contraction force in submandibular muscles when swallowing compared to normal controls. Further research is needed to determine if this inefficiency is consistent across larger samples and whether it is due to elevated baseline muscle activity, a compensatory behaviour to accomplish a more effective swallow, or both.

Effect of Volitional Effort on Submental Surface Electromyographic Activity During Healthy Swallowing

The effortful swallowing technique aims to compensate for or rehabilitate impaired swallowing by using maximal volitional effort to behaviorally modify aspects of swallowing physiology. Given that swallowing is a submaximal task, swallowing at submaximal levels has recently been suggested as a more task-specific therapeutic technique. The aim of this study was to investigate differences in muscle activity during minimum, regular, and maximum effort swallowing of different boluses and across different ages, with the goal of characterizing the task specificity of minimum effort and maximum effort swallowing. Forty-three healthy adults (22 female) representing four age groups (20-39, 40-59, 60-79, and 80 + years) participated in the study. They were verbally cued to swallow saliva and 5 mL water boluses using participant-determined minimum, regular, and maximum levels of effort, in randomized order. sEMG peak amplitude and duration of each swallow were measured. Linear mixed effects analyses demonstrated that compared to regular effort swallowing, maximum effort swallowing resulted in increased sEMG amplitude (p < .001) and prolonged duration (p < .001), while minimum effort swallowing resulted in decreased amplitude (p < .001) but no significant difference in duration (p = .06). These effects occurred regardless of age or bolus type. Differences in sEMG activity were smaller between regular and minimum effort swallowing than regular and maximum effort swallowing. Both increasing and decreasing volitional efforts during swallowing translate to significant modulation of muscle activity. However, regular swallowing is more similar to minimal effort swallowing. Results reinforce the concept of swallowing as a submaximal task, and provide insight into the development of sEMG biofeedback techniques for rehabilitation.

Expiratory Muscle Strength Training for Therapy of Pharyngeal Dysphagia in Parkinson's Disease

BACKGROUND

Pharyngeal dysphagia in Parkinson's disease (PD) is a common and clinically relevant symptom associated with poor nutrition intake, reduced quality of life, and aspiration pneumonia. Despite this, effective behavioral treatment approaches are rare.

OBJECTIVE

The objective of this study was to verify if 4 week of expiratory muscle strength training can improve pharyngeal dysphagia in the short and long term and is able to induce neuroplastic changes in cortical swallowing processing.

METHODS

In this double-blind, randomized, controlled trial, 50 patients with hypokinetic pharyngeal dysphagia, as confirmed by flexible endoscopic evaluation of swallowing, performed a 4-week expiratory muscle strength training. Twenty-five participants used a calibrated ("active") device, 25 used a sham handheld device. Swallowing function was evaluated directly before and after the training period, as well as after a period of 3 month using flexible endoscopic evaluation of swallowing. Swallowing-related cortical activation was measured in 22 participants (active:sham; 11:11) using whole-head magnetencephalography.

RESULTS

The active group showed significant improvement in the flexible endoscopic evaluation of swallowing-based dysphagia score after 4 weeks and after 3 months, whereas in the sham group no significant changes from baseline were observed. Especially, clear reduction in pharyngeal residues was found. Regarding the cortical swallowing network before and after training, no statistically significant differences were found by magnetencephalography examination.

CONCLUSIONS

Four-week expiratory muscle strength training significantly reduces overall dysphagia severity in PD patients, with a sustained effect after 3 months compared with sham training. This was mainly achieved by improving swallowing efficiency. The treatment effect is probably caused by peripheral mechanisms, as no changes in the cortical swallowing network were identified. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Validation of a Novel Wearable Electromyography Patch for Monitoring Submental Muscle Activity During Swallowing: A Randomized Crossover Trial

Purpose Surface electromyography (sEMG) is often used for biofeedback during swallowing rehabilitation. However, commercially available sEMG electrodes are not optimized for the head and neck area, have rigid form, and are mostly available in large medical centers. We developed an ultrathin, soft, and flexible sEMG patch, specifically designed to conform to the submental anatomy and which will be ultimately incorporated into a telehealth system. To validate this first-generation sEMG patch, we compared its safety, efficiency, and signal quality in monitoring submental muscle activity with that of widely used conventional sEMG electrodes. Method A randomized crossover design was used to compare the experimental sEMG patch with conventional (snap-on) sEMG electrodes. Participants completed the same experimental protocol with both electrodes in counterbalanced order. Swallow trials included five trials of 5- and 10-ml water. Comparisons were made on (a) signal-related factors: signal-to-noise ratio (SNR), baseline amplitude, normalized mean amplitude, and sEMG burst duration and (b) safety/preclinical factors: safety/adverse effects, efficiency of electrode placement, and satisfaction/comfort. Noninferiority and equivalence tests were used to examine signal-related factors. Paired t tests and descriptive statistics were used to examine safety/preclinical factors. Results Forty healthy adults participated (24 women, M _age = 67.5 years). Signal-related factors: SNR of the experimental patch was not inferior to the SNR of the conventional electrodes (p < .0056). Similarly, baseline amplitude obtained with the experimental patch was not inferior to that obtained with conventional electrodes (p < .0001). Finally, normalized amplitude values were equivalent across swallows (5 ml: p < .025; 10 ml: p < .0012), and sEMG burst duration was also equivalent (5 ml: p < .0001; 10 ml: p < .0001). Safety/preclinical factors: The experimental patch resulted in fewer mild adverse effects. Participant satisfaction was higher with the experimental patch (p = .0476, d = 0.226). Conclusions Our new wearable sEMG patch is equivalent with widely used conventional sEMG electrodes in terms of technical performance. In addition, our patch is safe, and healthy older adults are satisfied with it. With lessons learned from the current COVID-19 pandemic, efforts to develop optimal swallowing telerehabilitation devices are more urgent than ever. Upon further validation, this new technology has the potential to improve rehabilitation and telerehabilitation efforts for patients with dysphagia. Supplemental Material https://doi.org/10.23641/asha.12915509.

Application of Ultrasound Biofeedback to the Learning of the Mendelsohn Maneuver in Non-dysphagic Adults: A Pilot Study

This study aimed to investigate the application of ultrasound to the learning of swallowing maneuver. Forty non-dysphagic adults of both genders who were naïve to the Mendelsohn maneuver participated in the study. They were randomly assigned to receive ultrasound or surface electromyography (sEMG) as biofeedback when acquiring the Mendelsohn maneuver. Thirty-eight subjects (n = 19) completed the Learning phase. Accuracy of executing the Mendelsohn maneuver was measured immediately (Post-training percentage accuracy) and one week post-training (Retention percentage accuracy). Whereas comparable numbers of training blocks were completed by the two groups (t(31.51) = 3.68, p = 0.330), the Ultrasound group attained significantly higher percentage accuracies than the sEMG group at both Post-training (t(28.88) = 4.04, p < 0.001, d = 1.309) and Retention (t(30.78) = 2.13, p = 0.042, d = 0.690). Ultrasound is a more effective biofeedback than sEMG in the acquisition of the Mendelsohn maneuver and may be adopted to the rehabilitative treatment for dysphagic individuals. Non-specificity of sEMG as biofeedback should be emphasized when it is employed in the training and learning of swallowing maneuvers. Findings from the present study suggest that ultrasound is preferable to sEMG as biofeedback in the learning of the Mendelsohn maneuver.

A Systematic Review of the Physiological Effects of the Effortful Swallow Maneuver in Adults With Normal and Disordered Swallowing

Purpose This systematic review summarizes the biomechanical and functional effects of the effortful swallow in adults with and without dysphagia, highlighting clinical implications and future research needs. Specifically, the effects of the effortful swallow on swallowing physiology, safety, and efficiency were identified, as well as the strengths and limitations of current research. Method Recommendations specified by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses were followed. A literature search of three databases and relevant articles cited in the searched studies was performed. Two evaluators independently analyzed the studies for eligibility criteria, and final inclusion of studies was decided by consensus. Evaluators also assessed each study for quality of evidence. Results Twenty-three studies were included in this systematic review. Main findings indicated that the effortful swallow generated greater pressures in the tongue-to-palate, pharynx, upper esophageal sphincter, and esophageal regions. Inconsistent results for hyolaryngeal excursion were reported, as well as for swallowing function. Instructions of the effortful swallow varied greatly across studies. Two of the 23 studies were judged to be of high quality, and the remaining studies were of medium quality based on the quality indicators of this review. Conclusions Biomechanical effects of the effortful swallow included increased pressures in the oral, pharyngeal, and esophageal regions. Future investigations should address the effects of the effortful swallow in individuals with dysphagia and its potential role as a rehabilitative maneuver. Moreover, standardization of the effortful swallow instructions based on its physiological and functional effects is essential.

Motor Learning, Neuroplasticity, and Strength and Skill Training: Moving From Compensation to Retraining in Behavioral Management of Dysphagia

Purpose Learning a motor skill and regaining a motor skill after it is lost are key tenets to the field of speech-language pathology. Motor learning and relearning have many theoretical underpinnings that serve as a foundation for our clinical practice. This review article applies selective motor learning theories and principles to feeding and swallowing across the life span. Conclusion In reviewing these theoretical fundamentals, clinical exemplars surrounding the roles of strength, skill, experience, compensation, and retraining, and their influence on motor learning and plasticity in regard to swallowing/feeding skills throughout the life span are discussed.

A comprehensive review of the diagnosis and treatment of Parkinson's disease dysphagia and aspiration

INTRODUCTION

Bulbar dysfunction is common in Parkinson's disease (PD) with more than 80% of affected individuals developing dysphagia during the course of the disease. Symptoms can begin in the preclinical stage and individuals may remain clinically asymptomatic for years. Furthermore, patients may be unaware of swallowing changes, which contributes to the difference between the prevalence of self-reported dysphagia and deficits identified during instrumental evaluations. Dysphagia is underrecognized and contributes to the development of aspiration pneumonia which is the leading cause of death in PD. Dysphagia in PD is complex and not completely understood. Both dopaminergic and nondopaminergic pathways likely underpin dysphagia.

AREAS COVERED

This comprehensive review will cover the epidemiology, pathophysiology, clinical evaluation, and expert management of dysphagia and aspiration in patients with PD.

EXPERT OPINION

A multidisciplinary team approach is important to properly identify and manage PD dysphagia. Regular clinical screenings with objective instrumental assessments are necessary for early detection of dysphagia. Studies are needed to better understand the mechanism(s) involved in PD dysphagia, establish markers for early detection and progression, and develop evidence-based treatment options.

Surface Electromyographic Biofeedback and the Effortful Swallow Exercise for Stroke-Related Dysphagia and in Healthy Ageing

Dysphagia is common after stroke, leading to adverse outcome. The Effortful Swallow (ES) is recommended to improve swallowing but it is not known if dysphagic patients can increase muscle activity during the exercise or if age affects performance. Providing surface electromyographic (sEMG) biofeedback during dysphagia therapy may enhance exercise completion, but this has not been investigated and the technique’s acceptability to patients is not known. Aims: To determine if age or post-stroke dysphagia affect the ability to increase submental muscle activity during the ES, if sEMG biofeedback improves ES performance and if sEMG is an acceptable addition to therapy. In a Phase I study submental sEMG amplitudes were measured from 15 people with dysphagia < 3 months post-stroke and 85 healthy participants aged 18–89 years during swallowing (NS) and when they performed the ES with and without sEMG biofeedback. Participant feedback was collected via questionnaire. Measurements were compared with repeated measures ANOVA and age effects were examined with linear regression. Both groups produced significantly greater muscle activity for the ES than NS (p < 0.001) and significantly increased activity with biofeedback (p < 0.001) with no effect of age. Participant feedback about sEMG was very positive; over 98% would be happy to use it regularly. The ES is a physiologically beneficial dysphagia exercise, increasing muscle activity during swallowing. sEMG biofeedback further enhances performance and is considered an acceptable technique by patients. These findings support the potential application of sEMG biofeedback and the ES in dysphagia therapy in stroke, justifying further investigation of patient outcome.

Tracking Hyoid Bone Displacement During Swallowing Without Videofluoroscopy Using Machine Learning of Vibratory Signals

Identifying physiological impairments of swallowing is essential for determining accurate diagnosis and appropriate treatment for patients with dysphagia. The hyoid bone is an anatomical landmark commonly monitored during analysis of videofluoroscopic swallow studies (VFSSs). Its displacement is predictive of penetration/aspiration and is associated with other swallow kinematic events. However, VFSSs are not always readily available/feasible and expose patients to radiation. High-resolution cervical auscultation (HRCA), which uses acoustic and vibratory signals from a microphone and tri-axial accelerometer, is under investigation as a non-invasive dysphagia screening method and potential adjunct to VFSS when it is unavailable or not feasible. We investigated the ability of HRCA to independently track hyoid bone displacement during swallowing with similar accuracy to VFSS, by analyzing vibratory signals from a tri-axial accelerometer using machine learning techniques. We hypothesized HRCA would track hyoid bone displacement with a high degree of accuracy compared to humans. Trained judges completed frame-by-frame analysis of hyoid bone displacement on 400 swallows from 114 patients and 48 swallows from 16 age-matched healthy adults. Extracted features from vibratory signals were used to train the predictive algorithm to generate a bounding box surrounding the hyoid body on each frame. A metric of relative overlapped percentage (ROP) compared human and machine ratings. The mean ROP for all swallows analyzed was 50.75%, indicating > 50% of the bounding box containing the hyoid bone was accurately predicted in every frame. This provides evidence of the feasibility of accurate, automated hyoid bone displacement tracking using HRCA signals without use of VFSS images.

Respiratory muscle training in stroke patients with respiratory muscle weakness, dysphagia, and dysarthria - a prospective randomized trial

OBJECTIVE

To examine the efficacy of combined inspiratory and expiratory respiratory muscle training (RMT) with respect to the swallowing function, pulmonary function, functional performance, and dysarthria in patients with stroke.

DESIGN

Prospective, randomized controlled trial.

SETTING

Tertiary hospital.

PARTICIPANTS

The trial included 21 subjects (12 men, 9 women) aged 35 to 80 years presenting with 6 months history of unilateral stroke, respiratory muscle weakness (≥70% predicted maximal inspiratory pressure (MIP) and/or ≤70% maximal expiratory pressure (MEP)), dysphagia, or dysarthria. These subjects were randomly assigned to the control (n = 10, rehabilitation) and experimental (n = 11, rehabilitation with RMT) groups.

INTERVENTION

Inspiratory RMT starting from 30% to 60% of MIP and expiratory RMT starting from 15% to 75% of MEP for 5 days/week for 6 weeks.

MAIN OUTCOME MEASURES

MIP, MEP, pulmonary function, peak cough flow, perception of dyspnea, Fatigue Assessment Scale, Modified Rankin Scale, Brunnstrom stage, Barthel index, Functional Oral Intake Scale (FOIS), and parameters of voice analysis.

RESULTS

Significant differences were observed between both groups in terms of MIP, forced vital capacity (FVC), and forced expiratory volume per second (FEV1) of the percentage predicted. Significant difference was found with respect to the change in fatigue, shimmer percent, amplitude perturbation quotient, and voice turbulence index (VTI) according to the acoustic analysis in the RMT group. The FEV1/FVC ratio was negatively correlated with jitter percent, relative average perturbation, pitch perturbation quotient, and VTI; the maximum mid-expiratory flow (MMEF) and MMEF% were also negatively correlated with VTI. Significant differences among participants of the same group were observed while comparing the Brunnstrom stage before and after training of the affected limbs and the Barthel scale and FOIS scores in both the groups.

CONCLUSIONS

Altogether, 6-week combined inspiratory and expiratory RMT is feasible as adjuvant therapy for stroke patients to improve fatigue level, respiratory muscle strength, lung volume, respiratory flow, and dysarthria.Clinical trial registration number (Clinical Trial Identifier): NCT03491111.

Effects of Expiratory Muscle Strength Training on Videofluoroscopic Measures of Swallowing: A Systematic Review

Purpose Expiratory muscle strength training (EMST) is increasingly utilized in dysphagia rehabilitation; however, little is known about the effects of this approach on swallowing function or physiology. We conducted a systematic review to appraise and synthesize evidence regarding the effects of EMST on videofluoroscopic measures of swallowing in individuals with medical diagnoses, in which dysphagia is a concern. Method A literature search was conducted according to Cochrane guidelines. Of 292 nonduplicate articles, 11 were judged to be relevant for review. These underwent detailed review for study quality, risk of bias evaluation, and synthesis of swallowing outcomes. Results The selected articles described EMST in a variety of patient populations using either the EMST150 or the Phillips Threshold positive expiratory pressure device. The typical protocol involved five sets of five breaths through the device (25 breaths/day), 5 days per week for 4 weeks. Exercise loads were set between 50% and 75% depending on the population, and treatment was typically supervised by a clinician weekly. The Penetration-Aspiration Scale was the most commonly reported videofluoroscopic outcome measure. Conclusions differed as to whether or not swallowing improved following a course of EMST. Differences in videofluoroscopy protocols, methods of summarizing participant performance, and statistical approaches across studies meant that meta-analysis of swallowing outcomes could not be completed. Conclusion This review failed to find clear evidence regarding the effects of EMST on videofluoroscopic measures of swallowing. Heterogeneity in the etiologies and baseline severity of dysphagia across studies and in the methods used to measure swallowing outcomes was a particular barrier to data synthesis.

Flexible submental sensor patch with remote monitoring controls for management of oropharyngeal swallowing disorders

Successful rehabilitation of oropharyngeal swallowing disorders (i.e., dysphagia) requires frequent performance of head/neck exercises that primarily rely on expensive biofeedback devices, often only available in large medical centers. This directly affects treatment compliance and outcomes, and highlights the need to develop a portable and inexpensive remote monitoring system for the telerehabilitation of dysphagia. Here, we present the development and preliminarily validation of a skin-mountable sensor patch that can fit on the curvature of the submental (under the chin) area noninvasively and provide simultaneous remote monitoring of muscle activity and laryngeal movement during swallowing tasks and maneuvers. This sensor patch incorporates an optimal design that allows for the accurate recording of submental muscle activity during swallowing and is characterized by ease of use, accessibility, reusability, and cost-effectiveness. Preliminary studies on a patient with Parkinson's disease and dysphagia, and on a healthy control participant demonstrate the feasibility and effectiveness of this system.

High elevation training mask as a respiratory muscle strength training tool for dysphagia

BACKGROUND

Expiratory muscle strength training (EMST) is a treatment for swallowing dysfunction due to its activation of the suprahyoid muscles. Current EMST devices have numerous limitations.

OBJECTIVE

The purpose was to evaluate the utility of elevation training mask as an alternative respiratory muscle strength training (RMST) device.

METHODS

A closed system, simulating expiration was designed. Air was delivered through a pressure gauge with a measurement range of 0-15 psi. The EMST150TM and the Elevation Training Mask 2.0^® (ETM) maximal resistance levels were measured and compared.

RESULTS

EMST150 produced increasing expiratory resistance pressures of 0.3, 0.6, 1.2, 1.9 and 2.1 psi, which correspond to its indicator of 30, 60, 90, 120 and 150 cmH2O. The ETM resistance pressure produced expiratory resistance pressures of 0.1 and 0.2 psi at simulated altitudes of 3000 and 6000 feet, respectively. A stable expiratory resistance pressure of 0.25 psi was measured at simulated altitudes of 9000, 12,000, 15,000 and 18,000 feet.

CONCLUSION

ETM provides adjustable expiratory muscle strength resistance pressures. Further investigation is necessary to evaluate safety, compliance and clinical efficacy in patients with swallowing dysfunction.

SIGNIFICANCE

ETM can serve as an effective treatment modality for pulmonary dysfunction and swallowing disorders through RMST.

Expiratory muscle strength training improves swallowing and respiratory outcomes in people with dysphagia: A systematic review

PURPOSE

To investigate the effects of expiratory muscle strength training on communication and swallowing outcomes in adults with acquired motor based communication and/or swallowing difficulties of any aetiology.

METHOD

A systematic review was conducted. Six databases (CINAHL, MEDLINE, EMBASE, SPEECHBYTE, AMED and PUBMED) were searched from inception until end of May 2016. Randomised and non-randomised controlled studies and pre-test/post-test studies published in English that investigated the effects of expiratory muscle strength training were included. Study quality was assessed using the PEDro scale. Data were analysed descriptively and effect sizes and associated 95% confidence intervals were calculated.

RESULT

Seven articles reporting data from five studies were included. Preliminary data suggests expiratory muscle strength training improved airway safety during swallowing in people with dysphagia and increased the strength of the expiratory muscles in all patient groups. There was little evidence to suggest changes in communication outcomes after expiratory muscle strength training.

CONCLUSION

Speech-language pathologists might consider using expiratory muscle strength training to improve airway safety in adults with swallowing disorders.

Establishing a Multidisciplinary Head and Neck Clinical Pathway: An Implementation Evaluation and Audit of Dysphagia-Related Services and Outcomes

Head and neck cancer (HNC) guidelines recommend regular multidisciplinary team (MDT) monitoring and early intervention to optimize dysphagia outcomes; however, many factors affect the ability to achieve these goals. The aims of this study were to explore the barriers/facilitators to establishing and sustaining a MDT HNC care pathway and to examine the dysphagia-related speech-language pathology (SLP) and dietetic components of the pathway. Using the Consolidated Framework for Implementation Research (CFIR), a mixed methods study design was used to evaluate an established MDT HNC pathway. Ten MDT members provided perceptions of facilitators/barriers to implementing and sustaining the pathway. Patients attending the SLP and dietetic components of the pathway who commenced treatment between 2013 and 2014 (n = 63) were audited for attendance, outcome data collected per visit, and swallowing outcomes to 24-month post-treatment. Dysphagia outcomes were compared to a published cohort who had received intensive prophylactic dysphagia management. Multiple CFIR constructs were identified as critical to implementing and sustaining the pathway. Complexity was a barrier. Patient attendance was excellent during treatment, with low rates of non-compliance (< 15%) to 24 months. Collection of clinician/patient outcome tools was good during treatment, but lower post-treatment. Dysphagia outcomes were good and comparable to prior published data. The pathway provided patients with access to regular supportive care and provided staff opportunities to provide early and ongoing dysphagia monitoring and management. However, implementing and sustaining a HNC pathway is complex, requiring significant staff resources, financial investment, and perseverance. Regular audits are necessary to monitor the quality of the pathway.

Effect of the head extension swallowing exercise on suprahyoid muscle activity in elderly individuals

Aging causes motor function deterioration in the elderly population, which in turn can cause weakness in the muscles associated with swallowing. Swallowing-related problems in elderly individuals can be prevented or their symptoms can be improved with strengthening exercises for the muscles involved in swallowing. The existing strengthening exercises for the suprahyoid muscle have their limitations. Therefore, it is necessary to find another exercise that can be performed by individuals whose personal characteristics make it difficult for them to perform the existing exercises. In this study, we investigated the changes in suprahyoid muscle activation, tongue strength, and thickness of the suprahyoid muscle after 8 weeks of the head extension swallowing exercise (HESE). A total of 23 healthy elderly individuals participated in an 8-week exercise program (20 min/session, 2 times/week for 8 weeks). Suprahyoid muscle activation during effortful swallowing and the effortful-normal ratio were significantly increased at 8 weeks compared to the baseline values (p = 0.002, and 0.033, respectively). Tongue tip pressure, tongue base pressure, normal swallowing pressure, effortful swallowing pressure, and tongue tip endurance were significantly increased at 8 weeks compared with baseline (p = 0.014, 0.004, 0.046, 0.009, and 0.004, respectively). The thickness of the digastric muscle and that of the mylohyoid muscle were significantly increased at 8 weeks compared with baseline (p = 0.000 and 0.004, respectively). This study showed that HESE can be a good option for improving the suprahyoid muscle and tongue strength in the elderly population. Additionally, this exercise does not require any additional equipment and has the advantage of being able to be performed anytime and anywhere. A variety of exercise options tailored according to individual characteristics may be helpful in choosing the most appropriate exercise.

Submental Muscle Activation During Lingual Tasks in Healthy Adults

OBJECTIVE

Lingual strengthening exercises are established to improve lingual function, thereby oral swallowing. This study measured submental muscle activation during maximum isometric pressure (MIP) lingual tasks in healthy adults, tasks that are or can be adopted in lingual strengthening exercises. In addition, the effects of age and gender on submental muscle activation are examined.

METHOD

Forty-nine participants between the ages of 18 to 35 years and greater than 60 years were included in the study. Participants completed trials of intraoral MIP lingual elevation, protrusion, and depression, during which submental muscle activation was measured using surface electromyography (sEMG). Peak amplitude measures were normalized and log transformed, following which a three-way ANOVA was performed.

RESULTS

Peak amplitudes of submental muscle activation were highest during lingual MIP protrusion, followed by lingual depression, and were least during lingual elevation. No significant differences in peak amplitudes were observed between older and younger adults, but higher peak amplitudes were recorded in women.

CONCLUSION

The differential effects of lingual task, age, and gender on peak submental muscle activation are examined. The potential impact of incorporating tasks adopted in this study in lingual strengthening exercises to improve oral and pharyngeal swallowing is discussed.

Effects of bedside self-exercise on oropharyngeal swallowing function in stroke patients with dysphagia: a pilot study

[Purpose] The purpose of this study was to investigate the effect of self-exercise on oropharyngeal swallowing function in patients with dysphagia. [Subjects and Methods] Nine patients with dysphagia after stroke were recruited. Self-exercise including effortful swallowing, tongue strengthening, and shaker exercise was performed 5 times a week for 4 weeks. Swallowing function was evaluated using the videofluoroscopic dysphagia scale (VDS) based on a videofluoroscopic swallowing study. [Results] There were significant differences in both the oral and pharyngeal phases of the VDS before and after the intervention. [Conclusion] This study demonstrated that bedside self-exercise is a positive method to improve oropharyngeal swallowing function in patients with dysphagia after stroke.

Effect of the combination of Mendelsohn maneuver and effortful swallowing on aspiration in patients with dysphagia after stroke

[Purpose] This study investigated the effect of a combined method incorporating the Mendelsohn maneuver and effortful swallowing on aspiration in patients with dysphagia after stroke. [Subjects and Methods] Three patients with dysphagia were recruited. All patients were treated with a combined method consisting of the Mendelsohn maneuver and effortful swallowing. The intervention period was total 20 sessions. Evaluation was based on videofluoroscopic swallowing study and the degree of aspiration was assessed using penetration-aspiration scale. [Results] Before and after intervention, all participants showed a decrease in aspiration with liquid type and semisolid type food. [Conclusion] This study confirms that the combined method of the Mendelsohn maneuver and effortful swallowing has a positive effect on aspiration in patients with dysphagia after stroke.

Alterations to Swallowing Physiology as the Result of Effortful Swallowing in Healthy Seniors

A significant proportion of healthy seniors report difficulty swallowing, thought to result from age-related decline in muscle bulk/function. Effortful Swallowing (ES) is used both as a compensatory maneuver to improve pharyngeal propulsion/clearance and has been proposed as an exercise to improve pharyngeal strength. This study sought to quantify the immediate kinematic, temporal, and functional changes during an ES maneuver to quantify its exercise potential to combat age-related changes in swallowing. Videofluoroscopy data were collected from 44 healthy seniors (21 male) over 65 years old (mean = 76.9, SD = 7.1). Each participant swallowed six 5 ml boluses of Varibar nectar-thick liquids: three with regular effort and three using ES. Individual swallows (n = 260) were measured on pharyngeal constriction, pharyngeal shortening, laryngeal closure duration, hyoid movement duration, UES opening duration, stage transition duration, pharyngeal transit time, pharyngeal response duration, Normalized Residue Ratio Scale (NRRS), and the Penetration-Aspiration Scale (PAS). Non-parametric Wilcoxon Rank Sum for repeated measures tested the effect of ES on each outcome. Exact p-values were calculated based on permutation methods, individual p values < 0.008 was deemed to be significant. The ES maneuver significantly prolonged all temporal variables. While we found no significant differences for pharyngeal constriction, significantly less (i.e., worse) pharyngeal shortening was observed in ES condition compared with regular effort swallows. Further, significantly worse pyriform sinus residue (NRRSv) was observed in the ES condition. No differences between ES and regular effort swallows were noted for pharyngeal constriction, NRRSv or PAS. We speculate that these negative manifestations of worse kinematics (less pharyngeal shortening) and function (increase in NRRSp) may be the result of forced volitional manipulation of swallowing in the ES condition in an otherwise normal elderly swallow.

Expiratory muscle strength training for radiation-associated aspiration after head and neck cancer: A case series

OBJECTIVE/HYPOTHESIS

Expiratory muscle strength training (EMST) is a simple, inexpensive, device-driven exercise therapy. Therapeutic potential of EMST was examined among head and neck cancer survivors with chronic radiation-associated aspiration.

STUDY DESIGN

Retrospective case series.

METHODS

Maximum expiratory pressures (MEPs) were examined among n = 64 radiation-associated aspirators (per penetration-aspiration scale score ≥ 6 on modified barium swallow). Pre-post EMST outcomes were examined in a nested subgroup of patients (n = 26) who enrolled in 8 weeks of EMST (25 repetitions, 5 days/week, 75% load). Nonparametric analyses examined effects of EMST on the primary endpoint MEPs. Secondary measures included swallowing safety (Dynamic Imaging Grade of Swallowing Toxicity [DIGEST]), perceived dysphagia (M.D. Anderson Dysphagia Inventory [MDADI]), and diet (performance status scale for head and neck cancer patients [PSSHN]).

RESULTS

Compared to sex-matched published normative data, MEPs were reduced in 91% (58 of 64) of aspirators (mean ± standard deviation: 89 ± 37). Twenty-six patients enrolled in EMST and three patients withdrew. MEPs improved on average 57% (87 ± 29 to 137 ± 44 cm H₂ O, P < 0.001) among 23 who completed EMST. Swallowing safety (per DIGEST) improved significantly (P = 0.03). Composite MDADI scores improved post-EMST (pre-EMST: 59.9 ± 17.1, post-EMST: 62.7 ± 13.9, P = 0.13). PSSHN diet scores did not significantly change.

CONCLUSION

MEPs were reduced in chronic radiation-associated aspirators relative to normative data, suggesting that expiratory strengthening could be a novel therapeutic target to improve airway protection in this population. Similar to findings in neurogenic populations, these data also suggest improved expiratory pressure-generating capabilities after EMST and translation to functional improvements in swallowing safety in chronic radiation-associated aspirators.

LEVEL OF EVIDENCE

4. Laryngoscope, 128:1044-1051, 2018.

Biomechanical Quantification of Mendelsohn Maneuver and Effortful Swallowing on Pharyngoesophageal Function

Objective

To quantify the effects of 2 swallowing maneuvers used in dysphagia rehabilitation—the Mendelsohn maneuver and effortful swallowing—on pharyngoesophageal function with novel, objective pressure-flow analysis.

Study Design

Evaluation of intervention effects in a healthy control cohort.

Setting

A pharyngoesophageal motility research laboratory in a tertiary education facility.

Subjects

Twelve young healthy subjects (9 women, 28.6 ± 7.9 years) from the general public, without swallowing impairment, volunteered to participate in this study.

Methods

Surface electromyography from the floor-of-mouth musculature and high-resolution impedance manometry–based pressure flow analysis were used to assess floor-of-mouth activation and pharyngoesophageal motility, respectively. Subjects each performed 10 noneffortful control swallows, Mendelsohn maneuver swallows, and effortful swallows, with a 5-mL viscous bolus. Repeated measures analyses of variance was used to compare outcome measures across conditions.

Results

Effortful and Mendelsohn swallows generated greater floor-of-mouth contraction ( P = .001) and pharyngeal pressure ( P < .0001) when compared with control swallows. There were no changes at the level of the upper esophageal sphincter, except for a faster opening to maximal diameter during maneuver swallows ( P = .01). The proximal esophageal contractile integral was reduced during Mendelsohn swallows ( P = .001).

Conclusion

Effortful and Mendelsohn maneuver swallows significantly alter the pharyngoesophageal pressure profile. Faster opening of the upper esophageal sphincter may facilitate bolus transfer during maneuver swallows; however, reduced proximal esophageal contractility during Mendelsohn maneuver swallows may impair bolus flow and aggravate dysphagic symptoms.

Effects of expiratory muscle strength training on swallowing function in acute stroke patients with dysphagia

[Purpose] This study was conducted to identify the effects of expiratory muscle strength training on swallowing function in acute stroke patients with dysphagia. [Subjects and Methods] A total of 18 stroke patients with dysphagia were enrolled in the study. All participants were randomly assigned to either an experimental group (n=9) or a control group (n=9). All participants performed traditional-swallowing rehabilitation therapy in 30-minute sessions five times a week for four weeks; however, only the experimental group received expiratory muscle strength training. [Results] Both groups showed significant improvements after mediation. When compared with the control group, the functional dysphagia scale, vallecular residue, and penetration-aspiration scale were significantly improved in the experimental group. [Conclusion] Expiratory muscle strength training is an effective intervention for impaired swallowing function in acute strike patients with dysphagia.

Expiratory muscle strength training evaluated with simultaneous high-resolution manometry and electromyography

OBJECTIVE

To examine feasibility of a simultaneous high-resolution pharyngeal manometry (HRM) and electromyography (EMG) experimental paradigm to detect swallowing-related patterns of palatal, laryngeal, and pharyngeal muscle activity during expiratory training.

STUDY DESIGN

Technical report.

METHODS

Simultaneous HRM, surface submental, and intramuscular EMG were acquired in two healthy participants during five tasks: 10-cc water swallow, maximum expiratory pressure (MEP) testing, and expiratory muscle strength training (EMST) at three pressure levels (sham, 50%, and 75% MEP).

RESULTS

Experimental conditions were feasible. Velopharyngeal closing pressure, palate EMG activity, and pharyngeal EMG activity increased as expiratory load increased. In contrast, thyroarytenoid EMG activity was low during the expiratory task, consistent with glottic opening during exhalation. Submental EMG patterns were more variable during expiratory tasks. Intraluminal air pressures recorded with HRM were correlated with measured expiratory pressures and target valve-opening pressures of the EMST device.

CONCLUSION

Results suggest that a simultaneous HRM/EMG/EMST paradigm may be used to detect previously unquantified swallowing-related muscle activity during EMST, particularly in the palate and pharynx. Our approach and initial findings will be helpful to guide future hypothesis-driven studies and may enable investigators to evaluate other muscle groups active during these tasks. Defining mechanisms of action is a critical next step toward refining therapeutic algorithms using EMST and other targeted treatments for populations with dysphagia and airway disorders.

LEVEL OF EVIDENCE

4. Laryngoscope, 127:797-804, 2017.

[The effect of expiratory muscle strength training on the oral and respiratory functions of community-dwelling older people: An analysis using the swallowing, oral, phonatory, and respiratory muscle function indices]

PURPOSE

This study was performed to determine the effects of expiratory muscle strength training (EMST) on the oral and respiratory functions of community-dwelling older people.

METHODS

Older people using a visiting-rehabilitation center were divided into an intervention group of 31 subjects and a control group of 15 subjects. Those in the intervention group were assigned home training for 8 weeks, which included 5 sets of 5 breaths per day with a 75% load of the maximum expiratory pressure using an EMST device. The outcome indices included (1) oral functions, evaluated by the cumulative time spent swallowing three times and the maximum phonation time (MPT) and (2) respiratory functions, evaluated by the maximum expiratory pressure and maximum inspiratory pressure (MEP/MIP). An independent t-test and paired t-test were used to analyze the data.

RESULTS

The cumulative time spent swallowing three times was lower in the intervention group than in the control group. This difference remained significant even after adjusting for sex, age, and baseline values. The MPT was 2.1 seconds higher than baseline in the intervention group but 0.4 seconds lower than baseline in the control group. An average increase of 5.7 cmH₂O in the PEmax was observed in the intervention group compared with an average decrease of 4.6 cmH₂O in the control group, indicating a significant difference.

CONCLUSION

These results suggest that EMST improves the oral and respiratory functions of community elderly subjects. This may be explained by the fact that the pathway for swallowing is partially shared with that for phonation, which contributes to a shortened swallowing time by repeated suprahyoid muscle contractions.