Evaluating swallowing muscles essential for hyolaryngeal elevation by using muscle functional magnetic resonance imaging

Effects of effortful swallowing against kinesiology taping resistance on the swallowing function in patients with poststroke dysphagia: A randomized controlled trial

BACKGROUND

A dysphagia rehabilitation method using kinesiology taping (KT) was recently introduced, and its potential for clinical efficacy was demonstrated by evaluating muscle activity and thickness. However, its effect on the swallowing function in patients with dysphagia remains unclear. This study aimed to investigate the effects of effortful swallowing against KT resistance on the swallowing function in patients with post stroke dysphagia.

METHODS

Thirty patients with poststroke dysphagia were recruited and randomly assigned to the experimental and placebo groups. In the experimental group, the KT was attached to the front of the neck (the hyoid bone between the sternum) with a tension of approximately 70% to 80%, and effortful swallowing was performed against the KT tension. In contrast, the placebo group performed effortful swallowing with KT applied at the same location without tension. The intervention was performed 30 times/day, 5 days/week for 6 weeks. The videofluoroscopic dysphagia scale (VDS) and penetration-aspiration scale (PAS) based on a videofluoroscopic swallowing study were used to analyze oropharyngeal swallowing function.

RESULTS

The experimental group showed statistically significant improvements in the oral and pharyngeal phases of the VDS (P = .029 and .007, respectively) and PAS (P = .034) compared with the placebo group. Effect sizes were observed for the oral (0.3) and pharyngeal phases (0.5) of the VDS and PAS (1.1).

CONCLUSION

This study demonstrated that effortful swallowing against resistance to KT is an effective therapeutic exercise for improving the swallowing function in patients with poststroke dysphagia.

Relative Fundamental Frequency in Individuals with Globus Syndrome and Muscle Tension Dysphagia

OBJECTIVE

Relative fundamental frequency (RFF) has been investigated as an acoustic measure to assess for changes in laryngeal tension. This study aimed to assess RFF in individuals with globus syndrome, individuals with muscle tension dysphagia (MTDg), and individuals with typical voices.

METHODS

RFF values were calculated from the speech acoustics of individuals with globus syndrome (n = 12), individuals with MTDg (n = 12), and age- and sex-matched controls with typical voices (n = 24). An analysis of variance was performed on RFF values to assess the effect of group.

RESULTS

There was no statistically significant effect of group on RFF values, with similar values for individuals with globus syndrome, individuals with MTDg, and control participants.

CONCLUSIONS

These results suggest that individuals with these disorders do not appear to possess paralaryngeal muscle tension in a locus and/or manner that directly impacts voice production.

Oral and Pharyngeal Dysphagia in Adults

Patients with oral and pharyngeal dysphagia have difficulty forming a cohesive bolus and/or transferring food from the mouth into the pharynx and esophagus to initiate the involuntary swallowing process. This may be accompanied by nasopharyngeal regurgitation, aspiration, and a sensation of residual food remaining in the pharynx. Abnormalities affecting the upper esophageal sphincter, pharynx, larynx, or tongue, in isolation or combination, result in oropharyngeal dysphagia affecting either or both transit and airway protection. These issues can be addressed with a combination of management of the underlying systemic disease, with surgical intervention or with swallow therapy.

Irradiation dose to the swallowing apparatus impacts nutritional status in head and neck cancer patients-results from the prospective randomized HEADNUT trial

PURPOSE

To investigate the influence of radiation dose to the swallowing muscles on the nutritional status in patients with head and neck cancer undergoing primary or adjuvant (chemo)radiotherapy (C)RT.

METHODS

Between 2018 and 2020, 61 patients were prospectively randomized into the so-called HEADNUT trial (head and neck cancer patients undergoing nutritional intervention). Follow-up was continued until 2022. Contouring of the swallowing apparatus included the superior (scm), middle (mcm), and inferior constrictor muscle (icm), the cricopharyngeal muscle (cphm), and the esophageal inlet. Nutritional status was assessed by bioelectrical impedance analysis (BIA) at the beginning and the end of radiotherapy. The posttherapeutic nutritional status was evaluated by the BIA-derived fat-free mass index (FFMI; kg/m2). Malnutrition was assumed at FFMI values of < 15 (women) and < 17 (men) kg/m2. To find differences between dosimetric parameters in well- and malnourished patients, Mann-Whitney U test was used. To model the association between malnutrition and its potentially influencing variables, several logistic regression models were built.

RESULTS

The following parameters differed between well- and malnourished patients at the end of therapy: icm Dmean, V40Gy (%), V50Gy (%), and V60Gy (%), and sphm V40Gy (%). After entering these parameters into a multivariable logistic regression model (dosimetric model), icm Dmean (b = -0.12; Exp(b) = 0.88; 95% CI: 0.78-1.0; p = 0.06) and icm V40Gy (%; b = 0.06; Exp(b) = 1.07; 95% CI: 1-1.13; p = 0.04) proved to be independent dosimetric predictors of malnutrition. We only determined the cut-off value for predicting malnutrition for icm V40Gy (%) since it was the only parameter which met p < 0.05. The optimal cut-off value for the predictor V40Gy (%) based on the Youden Index was 85.6%. Another logistic regression model (dosimetric-clinical model) consisted of icm V40 (%) and the clinical parameters tumor localization, malnutrition before RT, gender, and combined chemotherapy. It was confirmed that both icm V40% (b = -1.9; Exp(b) = -2.7; 95% CI: 0.01-0.8; p = 0.03) and malnutrition at baseline (b = -1.9; Exp(b) = 4.4; 95% CI: 8.4-816.6; p = 0.0002) were independent predictors of subsequent malnutrition the end of RT.

CONCLUSION

Establishment of a normal nutritional status before the start of RT and adherence to dose constraints for the swallowing apparatus may prevent malnutrition in head and neck cancer patients at the end of therapy. Specifically, we suggest an icm V40Gy (%) of more than 86% to be predictive for nutritional complications.

Differentiation of Bolus Texture During Deglutition via High-Density Surface Electromyography: A Pilot Study

OBJECTIVE

Swallowing is a complex neuromuscular task. There is limited spatiotemporal data on normative surface electromyographic signal during swallow, particularly across standard textures. We hypothesize the pattern of electromyographic signal of the anterior neck varies cranio-caudally, that laterality can be evaluated, and categorization of bolus texture can be differentiated by high-density surface electromyography (HDsEMG) through signal analysis.

METHODS

An HDsEMG grid of 20 electrodes captured electromyographic activity in eight healthy adult subjects across 240 total swallows. Participants swallowed five standard textures: saliva, thin liquid, puree, mixed consistency, and dry solid. Data were bandpass filtered, underwent functional alignment of signal, and then placed into binary classifier receiver operating characteristic (ROC) curves. Muscular activity was visualized by creating two-dimensional EMG heat maps.

RESULTS

Signal analysis results demonstrated a positive correlation between signal amplitude and bolus texture. Greater differences of amplitude in the cranial most region of the array when compared to the caudal most region were noted in all subjects. Lateral comparison of the array revealed symmetric power levels across all subjects and textures. ROC curves demonstrated the ability to correctly classify textures within subjects in 6 of 10 texture comparisons.

CONCLUSION

This pilot study suggests that utilizing HDsEMG during deglutition can noninvasively differentiate swallows of varying texture noninvasively. This may prove useful in future diagnostic and behavioral swallow applications.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:2695-2703, 2023.

Chemodenervation of the Posterior Belly of the Digastric Muscle in Facial Synkinesis

Background: Patients with facial synkinesis may have jaw tightness and swallow discomfort despite chemodenervation of facial mimetic musculature, and the posterior belly of the digastric (PBD) muscle is a logical target to treat these symptoms. Learning/Study Objective: To compare patient-reported outcomes of botulinum toxin (BT) chemodenervation of the posterior belly of digastric muscle in patients with postparalytic facial synkinesis. Design Type: Retrospective review. Methods: Patients with facial synkinesis who underwent electromyography (EMG)-guided PBD BT chemodenervation in addition to their baseline therapeutic regimen were included. Pre- and post-treatment Synkinesis Assessment Questionnaires (SAQ) and a two-question survey regarding jaw tightness and swallow discomfort were administered. Results: Twenty-nine patients were included. An average of 5 U of BT-A was injected into the PBD, and 46.5 U across all facial muscles. From pre- to post-injection, patients demonstrated improvement in jaw tightness at rest (3.02 vs. 1.98/5.0, p < 0.001), with swallow (2.78 vs. 1.94/5.0, p < 0.001), and total SAQ (64.3 vs. 51.2/100, p < 0.001). Patients rated subjective benefit from PBD injection compared with prior treatments without PBD injection as 4.5/5.0. Conclusion: Synkinesis patients with jaw tightness or swallow discomfort may benefit from the addition of PBD injections to the therapeutic regimen.

Evaluation of morphological features of palatopharyngeus insertion into the thyroid cartilage

The attachment of the palatopharyngeus extended from the posterior end of the thyroid cartilage to the posterior margin of the inferior constrictor attachment that might contribute to successive swallowing movements. Laryngeal elevation is essential for proper swallowing and breathing. Recently, clinical research has demonstrated that the palatopharyngeus, a longitudinal muscle of the pharynx, is involved in the elevation of the larynx. However, the morphological relationship between the larynx and palatopharyngeus remains unclear. In the present study, we analyzed the attachment site and characteristics of the palatopharyngeus in the thyroid cartilage. We evaluated 14 halves of seven heads from Japanese cadavers (average age: 76.4 years); 12 halves, anatomically and two halves histologically. A part of the palatopharyngeus, which originated from the inferior aspect of the palatine aponeurosis, was attached to the inner and outer surfaces of the thyroid cartilage through collagen fibers. The attachment area extends from the posterior end of the thyroid cartilage to the posterior margin of the attachment site of the inferior constrictor. The palatopharyngeus may elevate the larynx with the suprahyoid muscles and contribute to successive movements of swallowing with surrounding muscles. Based on our findings and previous studies, palatopharyngeus with various muscle bundle directions may be essential for the coordination of continuous swallowing events.

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.

Volumetric Assessment of the Anterior Digastric Muscles: A Deeper Understanding of the Volumetric Changes With Aging

BACKGROUND

Targeting the deeper, subplatysmal structures in the neck has recently grown in popularity. In particular, interventions targeting the "bulky" anterior digastric (AD) muscle have been described with excellent results. However, much remains to be understood about the deep anatomy of the neck and the age-associated changes of the AD.

OBJECTIVES

The aim of this study was to examine the relationship between AD volume and age.

METHODS

This retrospective study calculated the AD volume from MRI segmentation in subjects between the ages of 20 to 92 years, scans of whom had previously been recorded. Those with compromised imaging due to pathology or artifact were excluded. Subjects were divided into 4 age-defined cohorts for clinical applicability.

RESULTS

This study included 129 patients (male n = 64) with a mean age of 52.3. The AD volume of the reference group was 3.2 cm3. A linear decrease in muscle volume was observed with age compared with the reference group: 2.95 cm3 in the 45- to 54-year-old cohort (P = 0.3), 2.7 cm3 in the 55- to 64-year-old cohort (P = 0.05), and 2.45 cm3 in the >65-year-old cohort (P < 0.001). Male sex (P = 0.0001) and laterality (P = 0.003) were associated with significantly larger volumes. Overweight and obese BMI classification was not associated with a significantly different volume than normal or underweight subjects (P = 0.067).

CONCLUSIONS

The study findings suggest an age-associated reduction in AD volume. Gender and laterality significantly affected volume, whereas BMI did not. Although the results do not support the theory of muscular hypertrophy with aging, they reveal that the perceived bulkiness may be due to changes in the surrounding anatomy affecting the morphology of the AD and subsequent blunting of the cervicomental angle.

Accuracy of High-Resolution Pharyngeal Manometry Metrics for Predicting Aspiration and Residue in Oropharyngeal Dysphagia Patients with Poor Pharyngeal Contractility

Several physiological metrics can be derived from pharyngeal high-resolution impedance manometry (HRPM), but their clinical relevance has not been well established. We investigated the diagnostic performance of these metrics in relation to videofluoroscopic (VFS) assessment of aspiration and residue in patients with oropharyngeal dysphagia. We analyzed 263 swallows from 72 adult patients (22-91 years) with diverse medical conditions. Metrics of contractility, upper esophageal sphincter (UES) opening and relaxation, flow timing, intrabolus distension pressure, and a global Swallow Risk Index (SRI) were derived from pressure-impedance recordings using pressure-flow analysis. VFS data were independently scored for airway invasion and pharyngeal residue using the Penetration-Aspiration Scale and the Normalized Residue Ratio Scale, respectively. We performed multivariate logistic regression analyses to determine the relationship of HRPM metrics with radiological outcomes and receiver-operating characteristic (ROC) analysis to evaluate their diagnostic accuracy. We identified aspiration in 25% and pharyngeal residue in 84% of the swallows. Aspiration was independently associated with hypopharyngeal peak pressure < 65 mmHg (HypoPeakP) [adjusted odds ratio (OR) 5.27; 95% Confidence Interval (CI) (0.99-28.1); p = 0.051], SRI > 15 [OR 4.37; 95% CI (1.87-10.2); p < 0.001] and proximal esophageal contractile integral (PCI) < 55 mmHg·cm·s [OR 2.30; 95% CI (1.07-4.96); p = 0.034]. Pyriform sinus residue was independently predicted by HypoPeakP < 65 mmHg [OR 7.32; 95% CI (1.93-27.7); p = 0.003], UES integrated relaxation pressure (UES-IRP) > 3 mmHg [OR 2.96; 95% CI (1.49-5.88); p = 0.002], and SRI > 15 [OR 2.17; 95% CI (1.04-4.51); p = 0.039]. Area under ROC curve (AUC) values for individual HRPM metrics ranged from 0.59 to 0.74. Optimal cut-off values were identified. This study demonstrates the diagnostic value of certain proposed and adjunct HRPM metrics for identifying signs of unsafe and inefficient bolus transport in patients with oropharyngeal dysphagia.

The relationship between sarcopenia, dysphagia, malnutrition, and frailty: making the case for proactive swallowing exercises to promote healthy aging

PURPOSE OF REVIEW

The purpose of this review is to summarize current evidence regarding the relationship between sarcopenia of the swallowing muscles, dysphagia, malnutrition, and frailty in the context of aging. Further, this review will provide preliminary support for proactive swallowing exercises to reverse and/or prevent sarcopenia of the swallowing muscles.

RECENT FINDINGS

Recent studies lend support to a cyclic relationship between sarcopenia of the swallowing muscles, dysphagia, malnutrition, and frailty. Unfortunately, all studies are limited by their study design and lack instrumental imaging of swallowing function. Research (in the limbs) supports the use of proactive exercises and protein supplementation to reverse sarcopenia, especially in prefrail individuals. This provides a foundation to design and test similar preventive exercises for the swallowing muscles.

SUMMARY

As the population is rapidly aging, it is vital to understand how the natural loss of muscle in aging impacts swallowing function and the downstream impact on nutritional and physical function. Prospective, longitudinal research with sophisticated outcome measures are required to fully understand this cycle and provide an opportunity to test methods for interrupting the cycle.

Hyoid displacement patterns in healthy swallowing

Objective

To describe the patterns of displacement of the hyoid bone in healthy individuals, considering their displacements during swallowing of different consistencies.

Methods

Two hundred one swallowing videofluoroscopy exams of 67 adult and elderly individuals without swallowing disorders were analyzed. Descriptive analysis was performed to identify and describe the patterns of displacement of the hyoid bone.

Results

Seven types of displacement of the hyoid bone were found: H1 (horizontal), H2 (short vertical and long horizontal), H3 (vertical and diagonal to upper), H4 (long vertical and short horizontal), H5 (vertical), H6 (diagonal), and H7 (brief). The standards were maintained in different consistencies. The most frequent pattern of displacement was type H2. The distribution of the types of displacement of the hyoid was different among men and women.

Conclusion

Seven patterns of displacement of the hyoid bone during swallowing of normal adults and older people have been described. The most frequent pattern of displacement was horizontal, with variations in distribution between men and women. The displacement pattern was maintained during the swallowing of the three different consistencies (thin, pasty and solid liquid).

Correlating muscle resection with functional swallow outcomes: An anatomic framework informed systematic review of the literature

OBJECTIVE

To perform a systematic review of studies reporting swallow-associated outcomes in patients who received surgery for head and neck cancer (HNC), informed by an anatomic and physiologic framework of pharyngeal phase of swallowing (Pearson's dual-sling model).

METHODS

PUBMED and Google Scholar databases were searched for peer-reviewed papers published between 1990 and 2019 using relevant MeSH terms. Exclusion criteria were 1) discussions comparing reconstruction techniques, 2) case-report/series (n < 10), 3) perspective articles, 4) papers comparing objective instrumental methods of swallowing evaluation, 5) animal/cadaver studies, 6) no instrumental or validated swallow assessment tools used, 7) papers that discuss/include radiotherapy treatment, 8) systematic reviews, 9) papers that discuss swallow training or rehabilitation methods. Two investigators reviewed papers meeting inclusion/exclusions criteria. Muscles resected, anatomic resection site, swallow outcomes, and patient treatment variables were collected.

RESULTS

A total of 115,020 peer-reviewed papers were identified. 74 papers were relevant to this review, 18 met inclusion and exclusion criteria, and none discussed surgical impact on the pharyngeal phase of swallowing using Pearson's dual-sling model. Most papers discussed the effect of tongue-base, supraglottic, or regional anatomic resection. Post-surgical resection Follow-up times ranged from 1 to 13 months. 67% of studies used objective instrumental swallow studies; 22% used patient reported outcome measures. Follow up time since surgical resection, time to feeding tube removal, feeding tube present/absent, aspiration severity were used to define dysphagia endpoints.

CONCLUSIONS

To date, no surgical HNC studies have used the dual-sling mechanism to guide study design, and dysphagia assessment has been inconsistent. To counsel patients on the effects of surgery on pharyngeal phase of swallow function, specialists need physiologically grounded research that correlates muscles resected with consistent measures of swallow function.

Outcomes of manual therapy on the biomechanics of swallowing in individuals with COPD

PURPOSE

Several swallowing disorders have been reported in chronic obstructive pulmonary disease (COPD) patients due to the mechanical disadvantage of the respiratory muscles caused by hyperinflation. To date, no reports have been found in the literature among the therapeutic strategies on the use of manual therapy (MT) to manage swallowing disorders in COPD. The aim of the study was to verify the outcomes of a TM program on the biomechanics of swallowing of individuals with COPD.

METHODS

18 individuals with a mean age of 66.06 ± 8.86 years, 61.1% (11) men, and a FEV1% mean of 40.28 ± 16.73 were evaluated before and after TM. The measures analyzed were: oral transit time, pharyngeal transit time (PTT), number of swallows, vallecular (VL) residue and pyriform sinuses, penetration/aspiration and hyolaryngeal excursion in liquid and pasty consistencies.

RESULTS

A significant difference was found in PTT (p=0.04), VL residue (p=0.03), maximal hyoid elevation (p=0.003), and displacement of hyoid (p=0.02) in the pasty consistency. In the liquid consistency, we found a decrease in VL residue (p=0.001).

CONCLUSION

The MT program influenced the swallowing biomechanics of COPD patients demonstrated by a reduction in PTT and VL residue and increased hyoid elevation and displacement in the pasty consistency. In the liquid consistency, a decrease in VL residue was found.

Dysphagia in amyotrophic lateral sclerosis: Quantification of bulbar motor dysfunction

BACKGROUND

Dysphagia as a sequel and possible early sign of amyotrophic lateral sclerosis (ALS) is caused by progressive impaired bulbar motor function.

OBJECTIVE

To evaluate bulbar motor dysfunction in patients suffering from ALS compared to a healthy reference group.

METHODS

A clinical study and prospective group comparison was designed. Patients and healthy volunteers were examined in the outpatient clinic of our university medical center. Ten patients with ALS and 20 healthy volunteers were included. All participants underwent a flexible endoscopic evaluation of swallowing (FEES) and a manometric measurement of the maximal sub-palatal atmospheric pressure generated by suction as well as of the prevalent pressure during swallowing. Additionally, the Sydney Swallow Questionnaire (SSQ) was completed by all participants to score the self-rated extent of dysphagia.

RESULTS

Comparing maximal suction pressures, the group of patients showed significantly lower values (p < .001). There was a significant correlation between reduced pressures and the degree of dysphagia (SSQ score) (r = -0.73).

CONCLUSIONS

As the oral cavity is an easily accessible compartment of the upper digestive tract, manometric measurements might serve as a simple instrument in order to detect or to monitor bulbar motor dysfunction. Oral manometry may facilitate early detection and monitoring of dysphagia in ALS. Larger studies are required to confirm our findings.

The effect of laryngeal elevation training on swallowing function in patients with dysphagia

OBJECTIVE

To investigate the effect of laryngeal elevation training without highly loaded head lifting on swallowing function in patients with dysphagia.

METHODS

Fifty-seven patients with dysphagia (36 men; mean age, 78.5 ± 11.4 years) were included. All participants performed the swallowing forehead exercise and the chin push-pull manoeuvre for two months. Videoendoscopy to assess swallowing function, the peak expiratory flow test and the hand grip strength test were performed at the initial visit (time 1) and two months after the start of the intervention (time 2). We used the Hyodo score, a scoring method for videoendoscopic assessment, for evaluation of swallowing function.

RESULTS

The linear mixed model showed a significant main effect of time (the Hyodo score at time 1 was greater than the score at time 2). The effects of the co-variates were not significant.

CONCLUSION

The present study demonstrated the significant effect of laryngeal elevation training without head lifting on the Hyodo score.

Using Ultrasound to Document the Effects of Expiratory Muscle Strength Training (EMST) on the Geniohyoid Muscle

Expiratory muscle strength training (EMST) is an exercise program designed to strengthen the muscles of expiration by increasing expiratory load during breathing exercises using either resistive or pressure threshold devices. Previous research has shown that EMST may increase submental suprahyoid muscle activity as measured with surface electromyography. The impact of EMST on submental muscles is of interest to those who treat dysphagia. The purpose of this study was to determine whether the cross-sectional area of the geniohyoid muscle changes as observed with ultrasound during a 5-week EMST program performed at 75% of maximum expiratory strength using the EMST150 device in healthy adults. Ten healthy adults participated in the 5-week program. Maximum expiratory pressure (MEP) and cross-sectional area of the geniohyoid muscle were measured weekly. Geniohyoid cross-sectional area was measured from ultrasound images recorded in the coronal plane. Repeated Measures ANOVA was used to determine whether there were significant changes among the dependent variables over the study period. Both MEP and geniohyoid area increased significantly in response to a 5-week program of EMST. EMST in healthy adults is effective at strengthening the geniohyoid muscle as reflected by significantly increased cross-sectional area measured with B-mode ultrasound. This is the first study to document weekly change in muscle morphology as a result of EMST. Increasing geniohyoid muscle mass and consequent strength through a program of EMST may be beneficial for persons with pharyngeal stage dysphagia resulting from reduced hyolaryngeal elevation, reduced laryngeal closure, or reduced UES opening.

Ultrasound: an emerging modality for the dysphagia assessment toolkit?

PURPOSE OF REVIEW

Videofluoroscopy (VFSS) and fibreoptic endoscopic evaluation of swallowing (FEES) are established instrumental techniques to support differential diagnosis and treatment of oropharyngeal dysphagia. Whilst their value is undisputed, each tool is not without limitations. The COVID-19 pandemic has restricted access to VFSS and FEES leading clinicians to explore alternative or augmentative tools to support swallowing assessment.Ultrasound (US) is an established tool for visualisation of head and neck anatomy, including structures implicated in swallowing. Although US has been utilised in swallowing research for many years, its application has not translated into common clinical practice. This review presents and debates the evidence for and against use of US for clinical swallowing assessment.

RECENT FINDINGS

Evaluation of swallowing muscle morphometry and measurement of isolated swallowing kinematics are two primary uses of US in swallowing assessment that have been identified in the literature. Use of US to detect bolus flow, aspiration and residues is in its early stages and needs further research.

SUMMARY

US shows promise as an adjunctive modality to support assessment of swallowing. With standardisation, these measurements may have potential for transition into clinical care. Reliability and validity testing and development of normative data are imperative to ensure its use as an evidence-based instrumentation.

The Relationships Between Radiation Dosage and Long-term Swallowing Kinematics and Timing in Nasopharyngeal Carcinoma Survivors

This study aimed to investigate the relationship between intensity-modulated radiation therapy (IMRT) dosimetry and swallowing kinematic and timing measures. Thirteen kinematic and timing measures of swallowing from videofluoroscopic analysis were used as outcome measures to reflect swallowing function. IMRT dosimetry was accessed for thirteen swallowing-related structures. A cohort of 44 nasopharyngeal carcinoma (NPC) survivors at least 3 years post-IMRT were recruited. The cohort had a mean age of 53.2 ± 11.9 years, 77.3% of whom were male. There was an average of 68.24 ± 14.15 months since end of IMRT; 41 (93.2%) had undergone concurrent chemotherapy. For displacement measures, female sex and higher doses to the cricopharyngeus, glottic larynx, and base of tongue were associated with reduced hyolaryngeal excursion and pharyngeal constriction, and more residue. For timing measures, higher dose to the genioglossus was associated with reduced processing time at all stages of the swallow. The inferior pharyngeal constrictor emerged with a distinctly different pattern of association with mean radiation dosage compared to other structures. Greater changes to swallowing kinematics and timing were observed for pudding thick consistency than thin liquid. Increasing radiation dosage to swallowing-related structures is associated with reduced swallowing kinematics. However, not all structures are affected the same way, therefore organ sparing during treatment planning for IMRT needs to consider function rather than focusing on select muscles. Dose-response relationships should be investigated with a comprehensive set of swallowing structures to capture the holistic process of swallowing.

Examining the Relationships Between Lingual Strength, Perihyoid Strength, and Swallowing Kinematics in Dysphagic Adults: A Retrospective Cross-Sectional Analysis

Purpose The aim of this study was to examine the relationships of clinical measures of lingual and perihyoid strength with displacement swallowing kinematics and swallowing safety in a heterogenous group of dysphagic adults. Method A retrospective analysis was completed of videofluoroscopic swallow studies of consecutive dysphagic outpatient adults presenting to a tertiary swallowing center from January 1, 2015, to December 31, 2017. Videofluoroscopic swallow study records were included if containing displacement swallowing kinematics of a 20-ml single liquid swallow and clinical measures of anterior (L-MIPA) or posterior (L-MIPP) lingual maximal isometric press, saliva mean swallowing pressures (S-MSP), and/or open mouth-maximal isometric press (OM-MIP). Regression analyses were used to examine the relationships between clinical measures of lingual (L-MIPA, L-MIPP, S-MSP) and perihyoid (OM-MIP) strength and displacement swallowing kinematics, and binomial logistic regressions were used to examine the relationships between clinical measures of lingual and perihyoid strength and swallowing safety (Penetration-Aspiration Scale [PAS]). Results Multivariate regressions revealed significant relationships of L-MIPA, L-MIPP, S-MSP, and OM-MIP with group-level changes to the displacement swallowing kinematics. Univariate analyses revealed significant relationships of L-MIPA and L-MIPP with pharyngeal constriction ratio, maximal extent of upper esophageal segment opening, and PAS. Conclusions Weak relationships were identified of clinical measures of lingual and perihyoid strength with displacement swallowing kinematics. These findings suggest that clinical measures of lingual and perihyoid strength do not fully explain impairments in swallowing kinematics across a heterogenous group of dysphagic patients. Weak-to-moderate relationships were identified between clinical measures of lingual strength and PAS, suggesting that they may have value in predicting functional measures of swallowing safety. Further research is needed to examine how findings may differ between specific patient populations.

Effect of Dysphagia Rehabilitation Using Kinesiology Taping on Oropharyngeal Muscle Hypertrophy in Post-Stroke Patients: A Double Blind Randomized Placebo-Controlled Trial

Background: It has recently been shown that suprahyoid muscle exercise using kinesiology taping (KT) increases the activation of the suprahyoid muscle in healthy adults, suggesting a potential therapeutic clinical exercise for dysphagia rehabilitation. This study investigated the effect of dysphagia rehabilitation using KT in stroke patients with dysphagia. Methods: Thirty subjects in South Korea were enrolled in this prospective placebo-controlled double-blind study. Participants were randomly assigned to the experimental and sham groups. In the experimental group, the tape was attached to the hyolaryngeal complex, pulled downward with approximately 70% tension, and then attached to the sternum and the clavicle bilaterally. In the sham group, the tape was applied similarly but without the tension. Both groups performed voluntary swallowing 50 times (10 times swallowing per set, times 5 sets) a day for 4 weeks with KT applied. Outcome measures were assessed using portable ultrasound equipment. The parameter measured was the change in thickness of the tongue muscle, mylohyoid muscle, and the anterior belly of the digastric muscle. Results: The experimental group showed statistically significant changes in the thickness of the tongue muscle, mylohyoid muscle, and anterior belly of the digastric muscle than the sham group (p = 0.007, 0.002, and 0.001). Conclusion: Dysphagia rehabilitation using KT is a technique that may promote oropharyngeal muscle thickness in patients with dysphagia after stroke.

Implementation of a Home-Based mHealth App Intervention Program With Human Mediation for Swallowing Tongue Pressure Strengthening Exercises in Older Adults: Longitudinal Observational Study

Background

Tongue pressure is an effective index of swallowing function, and it decreases with aging and disease progression. Previous research has shown beneficial effects of swallowing exercises combined with myofunctional tongue-strengthening therapy on tongue function. Tongue exercises delivered through mobile health (mHealth) technologies have the potential to advance health care in the digital age to be more efficient for people with limited resources, especially older adults.

Objective

The purpose of this study is to explore the immediate and long-term maintenance effects of an 8-week home-based mHealth app intervention with biweekly (ie, every 2 weeks) human mediation aimed at improving the swallowing tongue pressure in older adults.

Methods

We developed an mHealth app intervention that was used for 8 weeks (3 times/day, 5 days/week, for a total of 120 sessions) by 11 community-dwelling older adults (10 women; mean age 75.7 years) who complained of swallowing difficulties. The app included a swallowing monitoring and intervention protocol with 3 therapy maneuvers: effortful prolonged swallowing, effortful pitch glide, and effortful tongue rotation. The 8-week intervention was mediated by biweekly face-to-face meetings to monitor each participant’s progress and ability to implement the training sessions according to the given protocol. Preintervention and postintervention isometric and swallowing tongue pressures were measured using the Iowa Oral Performance Instrument. We also investigated the maintenance effects of the intervention on swallowing tongue pressure at 12 weeks postintervention.

Results

Of the 11 participants, 8 adhered to the home-based 8-week app therapy program with the optimal intervention dosage. At the main trial end point (ie, 8 weeks) of the intervention program, the participants demonstrated a significant increase in swallowing tongue pressure (median 17.5 kPa before the intervention and 26.5 kPa after the intervention; P=.046). However, long-term maintenance effects of the training program on swallowing tongue pressure at 12 weeks postintervention were not observed.

Conclusions

Swallowing tongue pressure is known to be closely related to dysphagia symptoms. This is the first study to demonstrate the effectiveness of the combined methods of effortful prolonged swallowing, effortful pitch glide, and effortful tongue rotation using mobile app training accompanied by biweekly human mediation in improving swallowing tongue pressure in older adults. The mHealth app is a promising platform that can be used to deliver effective and convenient therapeutic service to vulnerable older adults. To investigate the therapeutic efficacy with a larger sample size and observe the long-term effects of the intervention program, further studies are warranted.

International Registered Report Identifier (IRRID)

RR2-10.2196/19585

Determining the Underlying Relationship Between Swallowing and Maximum Vocal Pitch Elevation: A Preliminary Study of Their Hyoid Biomechanics in Healthy Adults

Purpose Deficiencies in swallowing (aspiration) and in maximum vocal pitch elevation have been shown to correlate in dysphagia. However, the underlying mechanisms that may explain this relationship are not known. In this study, we compare hyoid kinematics between swallowing and maximum vocal pitch elevation in healthy adults. Method Ten young (M = 21 ± 1.33 years) and eight older (M = 72.85 ± 5.59 years) healthy adults completed trials of maximum vocal pitch elevation (vowels /a/ and /i/) and swallowing (thin liquid and pudding) under videofluoroscopy. Superior and anterior hyoid excursions were obtained using kinematic analysis. Two-way analyses of variance and Spearman rho correlations were used to examine differences and relationships between swallowing and maximum pitch elevation biomechanics. Results Superior hyoid excursion was significantly greater for liquid swallows compared to pitch elevation tasks (/a/ and /i/; p = .002; Cohen's d = 1.28; p = .0179, Cohen's d = 1.03, respectively) and for pudding swallows compared to pitch tasks (p = .000, Cohen's d = 1.64; p = .001, Cohen's d = 1.38, respectively). Anterior hyoid excursion was not significantly different between the two functions, but was overall reduced in the older group (p = .0231, Cohen's d = .90). Furthermore, there was a moderate positive correlation between the degree of superior excursion during liquid swallows and maximum pitch elevation for both vowels (r s = .601, p = .001; r s = .524, p = .003) in young adults, and between the degree of anterior excursion during liquid swallows and pitch elevation for both vowels (r s = .688, p = .001; r s = .530, p = .008) in older adults. Conclusions Swallowing and maximum pitch elevation require similar anterior, but not superior, hyoid excursion in healthy adults. Differential correlations between the two tasks for each age group may be associated with age-related muscle changes. We provide evidence of partially shared biomechanics between swallowing and maximum pitch elevation.

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.

Comparison of 2 types of therapeutic exercise: jaw opening exercise and head lift exercise for dysphagic stroke: A pilot study

The aim of this study was to investigate the effect of the jaw opening exercise (JOE) on the thickness of the suprahyoid muscle and hyoid bone movement compared with the head lift exercise (HLE) in patients with dysphagia after strokeThis study recruited 30 patients with dysphagia after stroke. The JOE group performed a JOE using a resistance bar. The HLE group performed the traditional HLE. The total intervention duration was 6 weeks. We measured the thickness of the digastric and mylohyoid muscles using ultrasound. Two-dimensional motion analysis of the hyoid bone was performed using Image J software. The Borg rating of the perceived exertion scale was used to assess the intensity level of physical activity during the 2 exercises.Both groups showed a significant increase in the thickness of the digastric and mylohyoid muscles (P < .05). Hyoid bone motion was significantly increased in the anterior and superior movement in both groups (P < .05). After the intervention, there was no significant difference between the 2 groups. The Borg rating of perceived exertion scale for the JOE group was significantly lower than that of the HLE group (P < .05).In conclusion, this study demonstrated that the JOE and the HLE had similar effects with respect to increasing suprahyoid muscle thickness and improving hyoid bone movement. However, the JOE required less perceived exertion than the HLE.

Development of an Ultrasonic Doppler Sensor-Based Swallowing Monitoring and Assessment System

Existing swallowing evaluation methods using X-ray or endoscopy are qualitative. The present study develops a swallowing monitoring and assessment system (SMAS) that is nonintrusive and quantitative. The SMAS comprises an ultrasonic Doppler sensor array, a microphone, and an inertial measurement unit to measure ultrasound signals originating only from swallowing activities. Ultrasound measurements were collected for combinations of two viscosity conditions (water and yogurt) and two volume conditions (3 mL and 9 mL) from 24 healthy participants (14 males and 10 females; age = 30.5 ± 7.6 years) with no history of swallowing disorders and were quantified for 1st peak amplitude, 2nd peak amplitude, peak-to-peak (PP) time interval, duration, energy, and proportion of two or more peaks. The peak amplitudes and energy significantly decreased by viscosity and the PP time interval and duration increased by volume. The correlation between the time measures were higher (r = 0.78) than that of the amplitude measures (r = 0.30), and the energy highly correlated with the 1st peak amplitude (r = 0.86). The proportion of two or more peaks varied from 76.8% to 87.9% by viscosity and volume. Further research is needed to examine the concurrent validity and generalizability of the ultrasonic Doppler sensor-based SMAS.

Best Practices in Modified Barium Swallow Studies

Purpose The modified barium swallow study (MBSS) is a widely used videofluoroscopic evaluation of the functional anatomy and physiology of swallowing that permits visualization of bolus flow throughout the upper aerodigestive tract in real time. The information gained from the examination is critical for identifying and distinguishing the type and severity of swallowing impairment, determining the safety of oral intake, testing the effect of evidence-based frontline interventions, and formulating oral intake recommendations and treatment planning. The goal of this review article is to provide the state of the science and best practices related to MBSS. Method State of the science and best practices for MBSS are reviewed from the perspectives of speech-language pathologists (SLPs) and radiologists who clinically practice and conduct research in this area. Current quandaries and emerging clinical and research trends are also considered. Results This document provides an overview of the MBSS and standards for conducting, interpreting, and reporting the exam; the SLPs' and radiologist's perspectives on standardization of the exam; radiation exposure; technical parameters for recording and reviewing the exam; the importance of an interdisciplinary approach with engaged radiologists and SLPs; and special considerations for examinations in children. Conclusions The MBSS is the primary swallowing examination that permits visualization of bolus flow and swallowing movement throughout the upper aerodigestive tract in real time. The clinical validity of the study has been established when conducted using reproducible and validated protocols and metrics applied according to best practices to provide accurate and reliable information necessary to direct treatment planning and limit radiation exposure. Standards and quandaries discussed in this review article, as well as references, provide a basis for understanding the current best practices for MBSS.

The Impact of Dysphagia in Myositis: A Systematic Review and Meta-Analysis

(1) Background: Dysphagia is a clinical hallmark and part of the current American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) diagnostic criteria for idiopathic inflammatory myopathy (IIM). However, the data on dysphagia in IIM are heterogenous and partly conflicting. The aim of this study was to conduct a systematic review on epidemiology, pathophysiology, outcome and therapy and a meta-analysis on the prevalence of dysphagia in IIM. (2) Methods: Medline was systematically searched for all relevant articles. A random effect model was chosen to estimate the pooled prevalence of dysphagia in the overall cohort of patients with IIM and in different subgroups. (3) Results: 234 studies were included in the review and 116 (10,382 subjects) in the meta-analysis. Dysphagia can occur as initial or sole symptom. The overall pooled prevalence estimate in IIM was 36% and with 56% particularly high in inclusion body myositis. The prevalence estimate was significantly higher in patients with cancer-associated myositis and with NXP2 autoantibodies. Dysphagia is caused by inflammatory involvement of the swallowing muscles, which can lead to reduced pharyngeal contractility, cricopharyngeal dysfunction, reduced laryngeal elevation and hypomotility of the esophagus. Swallowing disorders not only impair the quality of life but can lead to serious complications such as aspiration pneumonia, thus increasing mortality. Beneficial treatment approaches reported include immunomodulatory therapy, the treatment of associated malignant diseases or interventional procedures targeting the cricopharyngeal muscle such as myotomy, dilatation or botulinum toxin injections. (4) Conclusion: Dysphagia should be included as a therapeutic target, especially in the outlined high-risk groups.

Swallowing in Obese Individuals before and after Bariatric Surgery

PURPOSE

To evaluate the oral and pharyngeal phases of swallowing in obese patients before and after bariatric surgery.

MATERIAL AND METHOD

Swallowing was evaluated by videofluoroscopy before and after 80 to 123 days from bariatric surgery in 19 individuals with obesity (15 women), aged 25-60 years. The body mass index (BMI) before surgery was from 40.1 to 57.0 kg/m². The surgical treatment was performed with laparoscopic Roux-en-Y gastric by-pass (RYGB). After surgery, the BMI ranged from 31.7 to 48.4 kg/m². The control group had 19 healthy volunteers (15 women), aged 22-56 years and BMI from 19.4 to 29.7 kg/m². Swallowing was evaluated with swallows of 5 mL of liquid and paste boluses in triplicate, and a solid bolus in duplicate.

RESULTS

With swallowing of liquid bolus, individuals with obesity had, before and after surgery, an increased frequency of premature posterior spillage. Before the surgery, the obese subjects had longer pharyngeal clearance of liquid compared with the control group and with individuals after the surgery. After the surgery, obese individuals had longer duration of the hyoid movement with liquid and paste boluses, compared with before surgery. Also, there was a reduction of the interval between the bolus entering the phaynx and the onset of upward hyoid excursion.

CONCLUSION

Non-operated obese patients had a longer pharyngeal clearance for liquid bolus compared with healthy controls. After bariatric surgery, there was an increase in hyoid movement duration.

MRI Assessment of Swallow Muscle Activation with the Swallow Exercise Aid and with Conventional Exercises in Healthy Volunteers: An Explorative Biomechanical Study

Swallowing muscle strength exercises are effective in restoring swallowing function. In order to perform the exercises with progressive load, the swallow exercise aid (SEA) was developed. Precise knowledge on which muscles are activated with swallowing exercises, especially with the SEA, is lacking. This knowledge would aid in optimizing the training program to target the relevant swallowing muscles, if necessary. Three healthy volunteers performed the three SEA exercises (chin tuck against resistance, jaw opening against resistance and effortful swallow) and three conventional exercises [conventional effortful swallow (cES), Shaker and Masako] in supine position inside an MRI scanner. Fast muscle functional MRI scans (generating quantitative T2-maps) were made immediately before and after the exercises. Median T2 values at rest and after exercise were compared to identify activated muscles. After the three SEA exercises, the suprahyoid, infrahyoid, sternocleidomastoid, and lateral pterygoid muscles showed significant T2 value increase. After the Shaker, the lateral pterygoid muscles did not show such an increase, but the three other muscle groups did. The cES and Masako caused no significant increase in any of these muscle groups. During conventional (Shaker) exercises, the suprahyoid, infrahyoid, and sternocleidomastoid muscles are activated. During the SEA exercises, the suprahyoid, infrahyoid, sternocleidomastoid, and lateral pterygoid muscles are activated. The findings of this explorative study further support the potential of the SEA to improve swallowing rehabilitation.

Effects of sitting posture and bolus volume on activation of swallowing-related muscles

BACKGROUND

The pharyngeal phase is a particularly important clinical factor related to swallowing dysfunctions. Head and neck posture, as well as bolus volume, are important factors affecting the pharyngeal stages of normal swallowing.

OBJECTIVE

The aim of our study was to identify the effects of sitting posture and bolus volume on the activation of swallowing-related muscles.

MATERIALS AND METHODS

Twenty-four subjects participated in the study. The subjects were positioned in three sitting postures-slump sitting (SS), lumbo-pelvic upright sitting (LUS), and thoracic upright sitting (TUS). While sitting in the chair, the subject was instructed to swallow 10 and 20 mL of water. Surface electromyography (EMG) was used to measure the muscle activity of the supra-hyoid (SH) and infra-hyoid (IH) muscles. Also, sitting posture alignment (head, cervical and shoulder angle) was also performed. Data were analysed with a repeated measures analysis of variance (RMANOVA) using a generalised linear model.

RESULTS

There was no significant difference in terms of the head angle (P = .395). However, significant differences were found in relation to the cervical angle (P < .001) and shoulder angle (P < .001). The TUS produced the lowest SH EMG activity (P = .001), in comparison to SS and LUS. The bolus volume for 20 mL showed greater SH and IH EMG activity (P < .001) than did the bolus volume for 10 mL.

CONCLUSIONS

Correcting sitting posture from SS to TUS may better assist swallowing-related muscles with less effort, irrespective of the bolus volume.

The effectivity of pharyngeal strengthening exercise, hyolaryngeal complex range of motion exercise, and swallowing practice in swallowing function of ischemic stroke patients with neurogenic dysphagia

Dysphagia is associated with an increased risk of aspiration pneumonia which often results in death in stroke patients. Therefore, effective and efficient management is important. Behavioral therapy for swallowing rehabilitation based on the principles of neuroplasticity such as oropharyngeal strengthening and range of motion exercises are the alternative ones that often be used. This study aimed to assess the changes in swallowing function in ischemic stroke patients with neurogenic dysphagia after pharyngeal strengthening exercise, hyolaryngeal complex range of motion exercise and swallowing practice. Swallowing function was assessed using Penetration Aspiration Scale (PAS) and Functional Oral Intake Scale (FOIS) based on Flexible Endoscopic Evaluation of Swallowing before and after interventions. The interventions were given every day with a duration of 30–45 minutes for 4 weeks. There were six subjects who completed the study. The PAS before the interventions were 6.00±1.79 and after the interventions was 1.67±0.82 (P=0.003). Meanwhile, the FOIS score before the interventions was 3 (1–5) and after the interventions were 5.00±2.10 (P=0.041). There was an improvement of PAS and FOIS after the interventions. Therefore, the interventions can be suggested to be used as one of the treatments to improve swallowing function in ischemic stroke patients with neurogenic dysphagia.

Effect of neuromuscular electrical stimulation combined with effortful swallowing using electromyographic biofeedback on oropharyngeal swallowing function in stroke patients with dysphagia: A pilot study

BACKGROUND

Electromyographic biofeedback (EMG-BF) is known to be an effective therapy for stroke rehabilitation. However, because few studies have investigated the therapy in patients with dysphagia, its effectiveness is not yet clear. This study aimed to investigate the effect of neuromuscular electrical stimulation (NMES) using EMG-BF on swallowing function in stroke patients with oropharyngeal dysphagia.

METHODS

In this study, 10 patients with dysphagia were recruited. The 1-group, pre-post study design was adopted. All subjects received NMES combined with EMG-BF in the suprahyoid area. Electrical stimulation was provided as a reward when the electrical signal generated by effortful swallowing reached a preset threshold. The intervention was provided for 30 minutes a day, 5 times a week for 4 weeks. The videofluoroscopic dysphagia scale (VDS) and penetration-aspiration scale (PAS) based on the videofluoroscopic swallowing study were used to evaluate the swallowing function.

RESULTS

Pre-intervention showed no significant differences in all items of VDS (P > .05). However, there was a statistically significant change in VDS from 13.36 ± 5.94 to 9.36 ± 5.14 (P = .015) in the oral phase, and from 38.36 ± 7.42 to 20.71 ± 14.61 (P = .016) in the pharyngeal phase. The PAS scores showed significant change from 5.14 ± 2.27 to 3.00 ± 1.00 (P = .031).

CONCLUSION

This study demonstrated that the use of NMES combined with EMG-BF had the potential to improve oropharyngeal swallowing in stroke patients with dysphagia.

Effectiveness of Therapy on Post-Extubation Dysphagia: Clinical and Electromyographic Findings

Introduction:

Patients who require prolonged endotracheal intubation (>48 hours) are at risk of dysphagia. Speech-language pathologists should perform swallowing exercises after extubation due to the high probability of developing aspiration pneumonia. There are no studies describing the use of swallowing techniques employed in post-extubation therapy aided by surface electromyography.

Objectives:

To evaluate the effects of swallowing function therapy in extubated patients after prolonged orotracheal intubation by means of clinical and electromyographic evaluation.

Methods:

A total of 15 patients were enrolled in this study (average age 48.6 ± 16.5 years). The study was carried out in three phases: (1) Clinical and electromyographic evaluation using the Dysphagia Risk Assessment Protocol following dysphagia scores criteria, and the measurement of the suprahyoid muscles amplitude (μV) expressed by root mean square (RMS), respectively; (2) swallowing rehabilitation program; and (3) reevaluation of patients after therapy. The Wilcoxon paired test assuming a significance level of 5% was used for statistical analysis.

Results:

By means of the swallowing scale, it was verified that patients suffered from severe oropharyngeal dysphagia at the first evaluation (80%), but the rehabilitation therapy reduced clinical signs, persistent only in one patient (6.7%) post-therapy, thus, improving swallowing. Significant differences, pre- and post-therapy, for suprahyoid muscles during maximal voluntary isometric contractions of right (P = .0067) and left (P = .0215), saliva swallowing by right (P = .0413) and left (P = .0151), and liquid swallowing by right (P = .0479) and left (P = .0215) sides, were found, as shown by electromyography.

Conclusions:

Swallowing exercises carried out by extubated patients after prolonged orotracheal intubation increased neuromuscular recruitment of suprahyoid muscles involved with swallowing and reduced dysphagia levels.

Functional Anatomy Underlying Pharyngeal Swallowing Mechanics and Swallowing Performance Goals

Purpose

Rehabilitation of pharyngeal swallowing dysfunction requires a thorough understanding of the functional anatomy underlying the performance goals of pharyngeal swallowing. These goals include the safe and efficient transfer of a bolus through the hypopharynx into the esophagus. Penetration or aspiration of a bolus threatens swallowing safety. Bolus residue indicates swallowing inefficiency. Several primary mechanics, or elements of the swallowing mechanism, underlie these performance goals, with some elements contributing to both goals. These primary mechanics include velopharyngeal port closure, hyoid movement, laryngeal elevation, pharyngeal shortening, tongue base retraction, and pharyngeal constriction. Each element of the swallowing mechanism is under neuromuscular control and is therefore, in principle, a potential target for rehabilitation. Secondary mechanics of pharyngeal swallowing, those movements dependent on primary mechanics, include opening the upper esophageal sphincter and epiglottic inversion.

Conclusion

Understanding the functional anatomy of pharyngeal swallowing underlying swallowing performance goals will facilitate anatomically informed critical thinking in the rehabilitation of pharyngeal swallowing dysfunction.

Functional Modules of Pharyngeal Swallowing Mechanics

OBJECTIVES

The present retrospective cohort study aims to test the hypothesis that elements of swallowing mechanics including hyoid movement, laryngeal elevation, tongue base retraction, pharyngeal shortening, pharyngeal constriction, and head and neck extension can be grouped into functional modules, and that these modules are predictably altered in disease states.

METHODS

Modified barium swallow video clips of a thick and a thin liquid swallow from 40 normal patients and 10 dysphagic post-treatment oropharyngeal head-and-neck cancer (HNC) patients were used in this study. Coordinate locations of 12 anatomical landmarks mapping pharyngeal swallowing mechanics were tracked on every frame during the pharyngeal phase of each swallow using a custom-made MATLAB tool. Morphometric modularity hypothesis testing was performed on these coordinate data to characterize the modular elements of swallowing function in each cohort using MorphoJ software.

RESULTS

The elements of normal swallowing can be grouped into four functional modules including bolus propulsion, pharyngeal shortening, airway protection, and head and neck posture. Modularity in HNC patient showed an intact airway protection module but altered bolus propulsion and pharyngeal shortening modules. To cross-validate the alteration in modules, a post hoc analysis was performed, which showed significantly increased vallecular (P < .04) and piriform (P < .05) residue but no significant change in aspiration status in the HNC cohort versus controls.

CONCLUSIONS

This study suggests that while pharyngeal swallowing mechanics is highly complex, the system is organized into functional modules, and that changes in modularity impacts swallowing performance. This approach to understanding swallowing function may help the patient care team better address swallowing difficulties.

LEVEL OF EVIDENCE

2b.

The Recline and Head Lift Exercises: A Randomized Clinical Trial Comparing Biomechanical Swallowing Outcomes and Perceived Effort in Healthy Older Adults

Purpose The aim of this study was to compare biomechanical swallowing outcomes and perceived effort as well as detraining effects of the established Head Lift Exercise (HLE) and the novel Recline Exercise (RE) in healthy older adults. Method Twenty-two healthy older adults were randomized to perform either the RE or the HLE for a period of 6 weeks. Subjects underwent videofluoroscopic swallowing studies at 3 time points (baseline, postexercise, and following a 6-week detraining period). Primary outcome measures included biomechanical measures of superior and anterior hyoid excursion and upper esophageal sphincter opening, obtained using kinematic analyses on the recorded swallows. Perceived exertion ratings during exercise, as measured by the Borg scale, were included as a secondary outcome measure. Linear mixed-effects models were utilized to compare exercise groups and evaluation time points. Results The 2 exercise groups did not differ significantly in age, body mass index, or body fat percentage at baseline. Significant postexercise increases were seen in superior hyoid excursion, F(2, 36.7) = 24.01, p ≤ .0001, and anterior hyoid excursion, F(2, 36.7) = 5.40, p = .0088, for both exercise groups. Upper esophageal sphincter opening did not increase significantly following the exercise regimens, F(2, 36.5) = 2.14, p = .1322. Both groups displayed a significant decrease in perceived exertion levels over the course of the exercises, F(5, 98) = 23.73, p ≤ .0001. On average, Borg ratings were 20% lower for the RE group than the HLE group at all time points, F(5, 20) = 7.94, p = .0106, indicating that this exercise was perceived as easier to perform. Eighteen participants were followed after detraining, and no differences in detraining effects were seen between groups. In general, gains in biomechanical measures were better maintained on larger bolus types. Conclusions In healthy older adults, the HLE and the RE produced similar gains and detraining effects in biomechanical swallow outcomes. The RE exercise, however, required significantly less effort. These findings suggest that the RE is easier to perform for healthy older adults and thus may be a valuable treatment option for individuals who have difficulty performing the HLE. Further investigation in patients with dysphagia is warranted. Supplemental Material https://doi.org/10.23641/asha.7742897.

Open Mouth-Maximal Isometric Press: Development and Norms for Clinical Swallowing Evaluations and Treatment

Purpose The aims of this study were to (a) describe the development and utility of the Open Mouth-Maximal Isometric Press (OM-MIP), a tool designed for the quantitative assessment of suprahyoid-infrahyoid muscle strength; (b) examine the effects of age and sex on the OM-MIP; and (c) establish age- and sex-based OM-MIP norms. Method Two hundred sixteen healthy male and female volunteers were recruited. Participants performed the OM-MIP, and the maximum of 3 trials that were within 10% of each other was recorded. Rest between each trial was allowed to avoid fatigue. Multiple regression examined the influence of age and sex on the OM-MIP. Descriptive statistics outlined normative OM-MIP values for young adult (aged 18-39 years), middle-aged adult (aged 40-59 years), old adult (aged 60-79 years), and very old adult (aged ≥ 80 years) men and women. Two-way analysis of variance determined if normative data differed significantly between the age and sex groups. Results Age and sex significantly influenced the OM-MIP, although no significant interaction effect was identified. Women had lower mean OM-MIPs when compared with men ( p < .0005), and very old adults had lower mean OM-MIPs when compared with young ( p = .001), middle-aged ( p < .0005), and old ( p = .013) adults. Conclusions This study establishes age- and sex-based OM-MIP norms and outlines its potential utility during clinical swallowing evaluations and treatment. By providing these norms, clinicians can begin to quantitatively measure suprahyoid and infrahyoid strength, individualize resistance training programs to patients' OM-MIP 1 repetition maximum, and track strength changes over time in response to therapeutic interventions.

An intensive swallowing exercise protocol for improving swallowing physiology in older adults with radiographically confirmed dysphagia

Purpose

The aim of this study was to investigate improvements in swallowing function and physiology in a series of healthy older adults with radiographically confirmed dysphagia, following completion of an exercise-based swallowing intervention.

Patients and methods

Nine otherwise healthy older adults (six females, mean age =75.3, SD =5.3) had confirmed impairments in swallowing safety and/or efficiency on a modified barium swallow study. Each participant completed an 8-week swallowing treatment protocol including effortful swallows, Mendelsohn maneuvers, tongue-hold swallows, supraglottic swallows, Shaker exercises and effortful pitch glides. Treatment sessions were conducted once per week with additional daily home practice. Penetration–Aspiration Scale and the Modified Barium Swallowing Impairment Profile (MBSImP) were scored in a blind and randomized fashion to examine changes to swallowing function and physiology from baseline to post-treatment.

Results

There were significant improvements in swallowing physiology as represented by improved oral and pharyngeal composite scores of the MBSImP. Specific components to demonstrate statistical improvement included initiation of the pharyngeal swallow, laryngeal elevation and pharyngeal residue. There was a nonsignificant reduction in median PAS scores.

Conclusion

Swallowing physiology can be improved using this standardized high-intensity exercise protocol in healthy adults with evidence of dysphagia. Future research is needed to examine the individual potential of each exercise in isolation and to determine ideal dose and frequency. Studies on various etiological groups are warranted.

Swallowing changes related to chronic temporomandibular disorders

OBJECTIVES

To investigate whether chronic temporomandibular disorder (TMD) patients showed any changes in swallowing compared to a control group. Moreover, it was examined whether swallowing variables and a valid clinic measure of orofacial myofunctional status were associated.

MATERIAL AND METHODS

Twenty-three patients with chronic TMD, diagnosed with disc displacement with reduction (DDR) and pain, according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD), and 27 healthy volunteers (control group) were compared. Surface electromyography (EMG) of the temporalis, masseter, sternocleidomastoid, and suprahyoid muscles was performed during swallowing tasks of thin liquid (10 and 15 mL) and spontaneous saliva. Data were normalized.

RESULTS

Compared to the control group, TMD patients showed a prolonged duration of swallowing for liquid and saliva and required a longer time to reach the activity peak and half the integral. While the overall mean value of the relative peaks was similar for the groups, the suprahyoid peak was significantly lower in the TMD group during swallowing of liquid. Moreover, TMD patients recruited the jaw elevator muscles proportionally more than controls. The orofacial myofunctional status was moderately correlated with EMG parameters.

CONCLUSION

Patients with chronic TMD showed temporal prolongation and changes in the relative activity of the muscles during the swallowing tasks.

CLINICAL RELEVANCE

The present results contribute additional evidence regarding the reorganization of muscle activity in patients with chronic TMD.

Functional Swallowing Units (FSUs) as organs-at-risk for radiotherapy. PART 1: Physiology and anatomy

BACKGROUND AND PURPOSE

When optimising radiotherapy treatments today, the pharyngeal constrictor muscles and the larynx are usually regarded as the swallowing organs at risk (SWOARs). The purpose of this study was to identify and describe additional, previously undefined groups of muscles (functional units) involved in crucial components of swallowing (hyolaryngeal elevation (HLE), tongue base retraction (TBR) and tongue motion), and to emphasise their relevance in radiation-induced dysphagia.

MATERIAL AND METHODS

Based on available literature on human anatomy and swallowing physiology, the functional units of muscles involved in HLE, TBR and tongue motion have been identified and described.

RESULTS AND CONCLUSION

Functional swallowing units (FSUs) were defined as groups of swallowing muscles sharing their function, that are in close proximity to each other. Seven FSUs involved in HLE, TBR and tongue motion were identified: floor of mouth, thyrohyoid muscles, posterior digastric/stylohyoid muscles complex, longitudinal pharyngeal muscles, hyoglossus/styloglossus muscles complex, genioglossus muscles, intrinsic tongue muscles. The swallowing physiology and anatomy of the FSUs described in this paper will lead to a greater understanding of radiation-induced dysphagia mechanisms and, consequently, to an improvement in the development of swallowing sparing strategies. This article (PART 1) serves as the theoretical foundation for a subsequent article (PART 2), which provides detailed delineation guidelines for FSUs.

Oropharyngeal swallowing function in patients with presbyphagia

[Purpose] This study investigated the characteristics of oropharyngeal swallowing function in patients with presbyphagia. [Participants and Methods] Data for 25 patients with presbyphagia were retrospectively analyzed. The oropharyngeal swallowing function was evaluated using VDS based on videofluoroscopic swallowing study. [Results] Lip closure, mastication, laryngeal elevation, and aspiration showed a relative decrease in function. [Conclusion] This study showed a reduction in oropharyngeal swallowing in patients with presbyphagia. Our results may help in the diagnosis and treatment of presbyphagia.

Treatment and evaluation of dysphagia rehabilitation especially on suprahyoid muscles as jaw-opening muscles

In our aging society, the number of patients with dysphagia, which is associated with disease and aging, is rapidly increasing. The swallowing reflex is a complex process that involves coordinated contractions of swallowing muscles. Many researchers have reported that age-related changes, such as frailty and sarcopenia, affect swallowing muscles and contribute to the decline in the swallowing function. Thus, simple, non-invasive evaluation methods and exercises for swallowing muscles in elderly patients with dysphagia are important.

Anterior–superior hyolaryngeal elevation during swallowing results from contractions of the suprahyoid muscle, which plays a primary role in opening the upper esophageal sphincter, along with relaxation of the cricopharyngeal muscle and laryngeal closure. Thus, many researchers have studied methods for evaluating and augmenting suprahyoid muscles. On the other hand, some researchers have reported on dysphagia rehabilitation focused on jaw-opening actions, because hyolaryngeal elevation muscles correspond with jaw-opening muscles. In this study, we describe a new dysphagia evaluation method and an exercise that focuses on suprahyoid muscles with application of jaw-opening actions.

Effects of Resistive Jaw-Opening Exercise with Elastic Bands on Suprahyoid Muscle Activation in Normal Subjects

OBJECTIVE

The effect of a resistive jaw-opening exercise using an elastic band on suprahyoid muscle activity and tongue strength was examined in healthy volunteers.

METHODS

Twenty-one adults wore an elastic loop around their head and mandible. To prescribe the appropriate elastic band resistance, the 10-repetition maximum (10 RM) was measured among 4 bands at baseline. Band loops, starting with the highest resistance value band, were sequentially applied to determine the suitability for 10 RM. During the exercise, the participants were required to open their jaw maximally and maintain the position for 10 s; then, they rested for 10 s. This procedure was repeated for 20 min, 3 days per week for 8 weeks to test suprahyoid muscle activation during effortful swallowing; isometric tongue pressures of the tongue tip and base at baseline, after 4, and after 8 weeks of training were measured.

RESULTS

Peak suprahyoid muscle activation amplitudes during effortful swallow and isometric pressures at the tongue tip significantly increased after 8 weeks.

CONCLUSION

The 8-week resistive jaw-opening exercise significantly improved strength of the suprahyoid muscle and tongue pressures in healthy subjects. These positive results warrant further investigation of the therapeutic effects and feasibility of this resistive exercise.