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

[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.

Therapeutic intervention in oropharyngeal dysphagia

Oropharyngeal dysphagia is a frequent consequence of several medical aetiologies, and even considered part of the normal ageing process. Early and accurate identification provides the opportunity for early implementation of dysphagia treatments. This Review describes the current state of the evidence related to dysphagia therapies - focusing on treatments most clinically utilized and of current interest to researchers. Despite successes in select studies, the level of evidence to support the efficacy of these treatments remains limited. Heterogeneity exists across studies in both how interventions are administered and how their therapeutic value is assessed, thereby making it difficult to establish external validation. Future work needs to address these caveats. Also, to be most efficacious, dysphagia therapies need to account for influences from pre-morbid patient characteristics as these factors have potential to increase the risk of dysphagia and the resulting complications of aspiration, malnutrition and psychological burden. Dysphagia therapies therefore need to incorporate the medical aetiology that is at its root, the resulting swallow physiology captured from comprehensive clinical and/or instrumental assessments, and the existing needs and supports of patients.

Identification of the most significant electrode positions in electromyographic evaluation of swallowing-related movements in humans

Surface electromyography (sEMG) is a well-established procedure for recording swallowing-related muscle activities. Because the use of a large number of sEMG channels is time consuming and technically sophisticated, the aim of this study was to identify the most significant electrode positions associated with oropharyngeal swallowing activities. Healthy subjects (N = 16) were tested with a total of 42 channels placed in M. masseter, M. orbicularis oris, submental and paralaryngeal regions. Each test subject swallowed 10 ml of water five times. After having identified 16 optimal electrode positions, that is, positions with the strongest signals quantified by the highest integral values, differences to 26 other ones were determined by a Mann-Whitney U test. Kruskal-Wallis H test was utilized for the analysis of differences between single subjects, subject subgroups, and single electrode positions. Factors associated with sEMG signals were examined in a linear regression. Sixteen electrode positions were chosen by a simple ranking of integral values. These positions delivered significantly higher signals than the other 26 positions. Differences between single electrode positions and between test subjects were also significant. Sixteen most significant positions were identified which represent swallowing-related muscle potentials in healthy subjects.

Electromyography and Mechanomyography Signals During Swallowing in Healthy Adults and Head and Neck Cancer Survivors

Surface electromyography (sEMG) is used as an adjuvant to dysphagia therapy to demonstrate the activity of submental muscles during swallowing exercises. Mechanomyography (MMG) has been suggested as a potential superior alternative to sEMG; however, this advantage is not confirmed for signal acquired from submental muscles. This study compared the signal-to-noise ratio (SNR) obtained from sEMG and MMG sensors during swallowing tasks, in healthy participants and those with a history of head and neck cancer (HNC), a population with altered anatomy and a high incidence of dysphagia. Twenty-two healthy adults and 10 adults with a history of HNC participated in this study. sEMG and MMG signals were acquired during dry, thin liquid, effortful, and Mendelsohn maneuver swallows. SNR was compared between the two sensors using repeated measures ANOVAs and subsequent planned pairwise comparisons. Test-retest measures were collected on 20 % of participants. In healthy participants, MMG SNR was higher than that of sEMG for dry [t(21) = -3.02, p = 0.007] and thin liquid swallows [t(21) = -4.24, p < 0.001]. Although a significant difference for sensor was found in HNC participants F(1,9) = 5.54, p = 0.043, planned pairwise comparisons by task revealed no statistically significant difference between the two sensors. sEMG also showed much better test-retest reliability than MMG. Biofeedback provided as an adjuvant to dysphagia therapy in patients with HNC should employ sEMG technology, as this sensor type yielded better SNR and overall test-retest reliability. Poor MMG test-retest reliability was noted in both healthy and HNC participants and may have been related to differences in sensor application.

A Pilot Study of the Head Extension Swallowing Exercise: New Method for Strengthening Swallowing-Related Muscle Activity

This pilot study examined the effect of a new head extension swallowing exercise (HESE) on submental muscle activity and tongue strength in healthy volunteers. Fifteen young adults (10 females and 5 males) were instructed to extend their head backwards as much as possible, and while watching the ceiling, swallowed their saliva every 10 s for a duration of 20 min. Twenty-four treatments were performed over 8 weeks. The outcome variables evaluated at baseline, 4 and 8 weeks of training, and 12-week follow-up included mean and peak submental muscle activation amplitudes during normal and effortful swallowing measured via surface electromyography, and anterior and posterior isometric tongue pressures were measured with the Iowa Oral Performance Instrument. Results indicated that the muscle activation amplitudes during effortful swallowing increased significantly at 4 and 8 weeks compared to baseline (p < 0.025). However, the increases in amplitudes during normal swallowing were minor (nonsignificant) after 8 weeks compared to baseline. The isometric pressures of the tongue tip and the posterior part of the oral tongue were significantly higher at 8 weeks compared to baseline (p < 0.025). Thus, the 8-week HESE protocol significantly improved suprahyoid muscle activity during effortful swallowing as well as the isometric tongue pressures. The HESE appears effective in exercising and strengthening the suprahyoid muscles and tongue muscles in healthy participants. Although encouraging, these results need to be replicated in clinical trials for testing the therapeutic effects of the HESE in older adults and patients with dysphagia who present with decreased hyolaryngeal elevation.

Effects of tongue-hold swallows on suprahyoid muscle activation according to the relative tongue protrusion length: a preliminary study

Tongue-hold swallow (THS) is a therapeutic maneuver used to increase the posterior pharyngeal wall motion during swallowing. This maneuver has also been reported to result in increased activation of the suprahyoid muscles. The hypothesis of this study was that the degree of suprahyoid muscle activation would depend on the tongue protrusion-length. The aim of this study was to investigate the activation levels of the suprahyoid muscles by surface electromyography (sEMG) while performing the THS maneuver at three tongue-protrusion lengths. Suprahyoid muscle activity during THSs was recorded in 25 adult volunteers (17 women and 8 men; age range 20-38 years). To record the activity of the suprahyoid muscles while the participants performed the maneuver, surface wireless EMG electrodes separated by a distance of 1 cm were placed on the skin on both sides of the midline under the chin. Each activity was recorded three times. Data analysis was performed by repeated-measures analysis of variance. Our results revealed that participants exhibited greater electrical activity during THS with 2/3rd or maximal tongue protrusion as compared to THS with 1/3rd tongue protrusion (p ≤ 0.001). To maximize the therapeutic effect of the THS maneuver, it is advised to protrude the tongue maximally as long as swallowing is possible.

Effects of tongue pressing effortful swallow in older healthy individuals

INTRODUCTION

The risk of swallowing disorders is increased for older individuals due to weak tongue and pharyngeal muscle strength. This study was appraised the value of a preventative approach by developing the tongue pressing effortful swallow (TPES) applied using a home-based and self-administered procedure. The TPES was developed by combining two swallowing exercises: tongue strengthening exercise and the effortful swallow. The purpose of this study was to examine the effects of the TPES on maximum tongue pressure and peak amplitude of submental muscle activity in older individuals.

MATERIAL AND METHODS

27 older individuals (mean 73 years) performed a 4-week TPES. The exercise program was adapted to a home-based and self-administered procedure. The maximum tongue pressure was measured by the Iowa Oral Performance Instrument and peak amplitude of submental muscle activity by surface electromyography (sEMG). Statistical comparisons were made by a matched pairs t-test (p<0.05).

RESULTS

The results of this study showed that the TPES had statistically significant and positive effects on increasing maximum tongue pressure, but the peak amplitude of the submental sEMG did not differ between before and after exercises.

CONCLUSIONS

The TPES had a positive impact in older individuals. The TPES, a combining exercise, was possible because two exercises had common physiological events. The TPES was a more innovative and efficient approach than the tongue strengthening exercise alone. In addition, older individuals were able to perform the swallowing exercise at home and by themselves with little assistance. Future research needs to refine the TPES and apply it to patients with dysphagia.

Effect of body posture on involuntary swallow in healthy volunteers

Clinically, reclining posture has been reported to reduce risk of aspiration. However, during involuntary swallow in reclining posture, changes in orofacial and pharyngeal movement before and during pharyngeal swallow should be considered. Further, the mechanisms underlying the effect of body posture on involuntary swallow remain unclear. The aim of the present study was to determine the effect of body posture on activity patterns of the suprahyoid muscles and on patterns of bolus transport during a natural involuntary swallow. Thirteen healthy male adults participated in a water infusion test and a chewing test. In the water infusion test, thickened water was delivered into the pharynx at a very slow rate until the first involuntary swallow was evoked. In the chewing test, subjects were asked to eat 10 g of gruel rice. In both tests, the recording was performed at four body postures between upright and supine positions. Results showed that reclining changed the location of the bolus head at the start of swallow and prolonged onset latency of the swallowing initiation. Muscle burst duration and whiteout time measured by videoendoscopy significantly increased with body reclining and prolongation of the falling time. In the chewing test, reclining changed the location of the bolus head at the start of swallow, and the frequency of bolus residue after the first swallow increased. Duration and area of EMG burst and whiteout time significantly increased with body reclining. These data suggest that body reclining may result in prolongation of pharyngeal swallow during involuntary swallow.

Efeitos do exercício muscular respiratório na biomecânica da deglutição de indivíduos normais

RESUMO: Objetivo: analisar os efeitos do exercício respiratórios na biomecânica da deglutição de sujeitos normais. Métodos: o exercício muscular respiratório em sujeitos normais foi aplicado por sete dias consecutivos por meio de incentivador respiratório a fluxo (três séries de dez repetições para inspiração e expiração). A biomecânica da deglutição foi avaliada por videofluoroscopia, utilizando variáveis temporais (tempo de transição faríngea) e visuoperceptuais (número de deglutições, resíduos em seios piriformes e valéculas, penetração/aspiração). Para análise estatística foi aplicado o Teste de Wilcoxon, Igualdade de Duas Proporções e Kappa. Resultados: foram avaliadas 16 jovens do sexo feminino com média de idade de 21,2±3,4 anos. Nas variáveis visuoperceptuais observou-se concordância quase perfeita entre os avaliadores (p<0,001), bem como na temporal (p = 1,00). Após o período de treinamento houve redução no tempo de transição faríngea (p=0,02). Conclusão: o uso de incentivador respiratório a fluxo influenciou significantemente na biomecânica da deglutição, principalmente na redução do tempo de transição faríngea.

The Relationship Between Submental Surface Electromyography and Hyo-Laryngeal Kinematic Measures of Mendelsohn Maneuver Duration

PURPOSE

The Mendelsohn Maneuver (MM) is a commonly prescribed technique that is taught to individuals with dysphagia to improve swallowing ability. Due to cost and safety concerns associated with videofluoroscopy (VFS) use, submental surface electromyography (ssEMG) is commonly used in place of VFS to train the MM in clinical and research settings. However, it is unknown whether ssEMG accurately reflects the prolonged hyo-laryngeal movements required for execution of the MM. The primary goal of this study was to examine the relationship among ssEMG duration, duration of laryngeal vestibule closure, and duration of maximum hyoid elevation during MM performance.

METHOD

Participants included healthy adults and patients with dysphagia due to stroke. All performed the MM during synchronous ssEMG and VFS recording.

RESULTS

Significant correlations between ssEMG duration and VFS measures of hyo-laryngeal kinematic durations during MM performance ranged from very weak to moderate. None of the correlations in the group of stroke patients reached statistical significance.

CONCLUSION

Clinicians and researchers should consider that the MM involves novel hyo-laryngeal kinematics that may be only moderately represented with ssEMG. Thus, there is a risk that these target therapeutic movements are not consistently being trained.

The capacity for volitional control of pharyngeal swallowing in healthy adults

INTRODUCTION

Previous research has documented that pressure and duration of brainstem-generated pharyngeal swallowing can be cortically modulated. But there is a commonly held belief that the sequence of pharyngeal pressure remains constant. However, Huckabee et al. [19] reported a patient cohort who demonstrated reduced latency of peak pressure in the proximal and distal pharynx, disproportionate and sometimes inversely correlated with overall swallowing duration, suggesting independent timing of underlying muscle contraction within the overall pharyngeal response. This study examined if healthy adults can volitionally produce altered latency of pharyngeal closure in isolation following intensive training, thereby evaluating the capacity for pharyngeal adaptation in a healthy system.

METHOD

Six healthy participants were seen for intensive training, consisting of daily one-hour sessions over two weeks (10 days) using pharyngeal manometry as a visual biofeedback modality. The participants were instructed to produce simultaneous pressure in the pharyngeal sensors when swallowing. The temporal separation of peak proximal and distal pharyngeal pressure was measured with discrete-sensor pharyngeal manometry at baseline, during training with biofeedback, and following training without biofeedback.

RESULTS

Following intensive training, participants were able to reduce temporal separation of peak pressure between the proximal and distal pharyngeal sensors from a baseline median of 188 ms (IQR=231 ms) to 68 ms (IQR=92 ms; p=0.002). In contrast, there was no significant change in overall swallowing duration during training (p=0.41). However, change in pharyngeal pressure latency was moderately correlated with both change in swallowing duration (r=0.444) and amplitude (r=0.571) during training, and there was a reduction in swallowing duration post-training (p=0.03).

CONCLUSION

Given intensive manometric biofeedback training, participants substantially reduced temporal separation of peak proximal and distal pharyngeal pressure when volitionally swallowing. However, correlation with overall pressure and duration measures suggest the adaptation was one of modulating the cumulative pharyngeal response rather than altering discrete components of timing of pharyngeal pressure in isolation. This is inconsistent with the pattern of behaviour documented by Huckabee et al. [19] in the patient population. Further research on modulatory control over targeted aspects of the pharyngeal swallow is needed, and may provide avenues for rehabilitative treatment of patients with dysphagia.

Is There a Role for Exercise in the Management of Bulbar Dysfunction in Amyotrophic Lateral Sclerosis?

PURPOSE

The role of exercise in the management of people with amyotrophic lateral sclerosis (PALS) is controversial and currently unclear. The purpose of this review article is to review literature examining the impact of limb, respiratory, and oral motor exercise on function, disease progression, and survival in PALS and the transgenic ALS animal model.

METHOD

A literature review was conducted to examine relevant studies published in peer-reviewed journals between 1960 and 2014. All studies were appraised for quality of research and were assigned a level of evidence, and treatment outcomes were classified as either positive, negative, or neutral.

RESULTS

A total of 18 exercise-based intervention studies on limb (13), respiratory (3), or speech (2) function were identified. Of the human clinical trials, 6 were experimental and 4 were exploratory. No experimental studies were identified examining the impact of targeted exercise on speech or swallowing function. Mild to moderate intensity limb or respiratory exercise, applied early in the disease, was noted to have a beneficial impact on motor function and survival.

CONCLUSION

Insufficient data exist to support or refute the role of exercise in the management of bulbar dysfunction in PALS. This represents a critical area of future investigation.

Submental Muscle Activity is Delayed and Shortened During Swallowing Following Stroke

OBJECTIVE

To evaluate the activities of the submental muscles using surface electromyography (sEMG) in patients presenting with dysphagia secondary to middle cerebral artery (MCA) infarction, and to compare the results with those in healthy volunteers.

DESIGN

Retrospective study design.

SETTING

A dysphagia clinic at a tertiary care university hospital.

PARTICIPANTS

Twenty-one patients presenting with dysphagia after unilateral MCA infarction were recruited into the study within 2 months of stroke onset. To serve as a control group, 13 healthy volunteers were enrolled.

MAIN OUTCOME MEASURES

The primary sEMG parameters were swallowing onset, pretrigger duration, swallowing duration, and swallowing amplitude. Swallowing functional outcome was evaluated using the Videofluoroscopic Dysphagia Scale and the American Speech-Language-Hearing Association National Outcome Measurement System.

RESULTS

Patients with MCA infarction demonstrated significantly delayed swallowing onset (P < .001) and shorter swallowing duration (P = .003) compared with the controls. Duration from the start of sEMG activity and actual laryngeal elevation also was delayed in the patient group (P = .042). At a cut-off point of 0.13 seconds for swallowing onset, sensitivity was 85.7% and specificity was 69.2%. For swallowing duration, sensitivity was 84.6% and specificity was 66.7% with 1.05 seconds as the cut-off point.

CONCLUSIONS

Patients with MCA infarction showed not only delayed swallowing onset and pretrigger duration, but also shorter duration of sEMG activity compared with those in healthy volunteers. Our results suggest that dysphagia after stroke might be further compromised by delayed laryngeal response especially after the start of suprahyoid muscle activity, which represents impaired laryngeal protection mechanism.

Functional outcomes associated with expiratory muscle strength training: narrative review

This review presents the available evidence for the effects of expiratory muscle strength training (EMST) with the use of a pressure threshold device. The investigators used computerized database searches for studies reporting the outcomes of pressure threshold EMST published after 1994. A total of 24 selected articles presented outcomes related but not limited to respiratory function, such as speech, swallow, voice, and cough function in persons with neurologic conditions such as Parkinson disease, multiple sclerosis, and Lance-Adams syndrome; in persons with respiratory diseases, such as chronic obstructive pulmonary disease; and in healthy young adults and sedentary and active elderly. Several studies demonstrated promising outcomes of EMST as a non-task-specific training for airway protection in persons with dysphagia secondary to neuromuscular impairments; however, further research is needed to confirm and generalize the reported findings.

Detraining outcomes with expiratory muscle strength training in Parkinson disease

Expiratory muscle strength training (EMST) is efficacious for improving maximum expiratory pressure (MEP), cough function, and swallowing safety in Parkinson disease (PD). However, there are no published reports describing detraining effects following EMST in persons with PD. Moreover, there are no published reports describing detraining effects following any behavioral swallowing intervention. Ten participants with PD underwent 3 mo of detraining following EMST. Measures of MEP and swallowing safety were made prior to beginning EMST (baseline), posttreatment (predetraining), and 3 mo postdetraining. Participants demonstrated, on average, a 19% improvement in MEP from pre- to post-EMST. Following the 3 mo detraining period, MEP declined by 2% yet remained 17% above the baseline value. No statistically significant changes were found in swallowing safety from post-EMST to postdetraining period. Following the 3 mo detraining period, seven participants demonstrated no change in swallowing safety, one worsened, and two had improvements. This preliminary study highlights the need for the design of maintenance programs to sustain function following intensive periods of training.

Effect of expiratory resistive loading in expiratory muscle strength training on orbicularis oris muscle activity

[Purpose] The purpose of this study was to elucidate the effect of expiratory resistive loading on orbicularis oris muscle activity. [Subjects] Subjects were 23 healthy individuals (11 males, mean age 25.5±4.3 years; 12 females, mean age 25.0±3.0 years). [Methods] Surface electromyography was performed to measure the activity of the orbicularis oris muscle during maximum lip closure and resistive loading at different expiratory pressures. Measurement was performed at 10%, 30%, 50%, and 100% of maximum expiratory pressure (MEP) for all subjects. The t-test was used to compare muscle activity between maximum lip closure and 100% MEP, and analysis of variance followed by multiple comparisons was used to compare the muscle activities observed at different expiratory pressures. [Results] No significant difference in muscle activity was observed between maximum lip closure and 100% MEP. Analysis of variance with multiple comparisons revealed significant differences among the different expiratory pressures. [Conclusion] Orbicularis oris muscle activity increased with increasing expiratory resistive loading.

Nonsurgical treatment: swallowing rehabilitation

This article provides an overview of nonsurgical and nonpharmacologic treatments for oropharyngeal dysphagia. The speech-language pathologist (SLP) is the primary member of the swallowing management team who will provide this type of dysphagia management. The primary focus of the SLP for dysphagia management is first to eliminate or reduce aspiration risk, as well as to improve or restore swallowing function. Ultimately, the management plan will depend on the physiologic underpinnings of the disorder and patient variables such as cognition, motivation, and ability to attend therapy sessions or participate in therapy.

Surface electromyograph activity of submental muscles during swallowing and expiratory muscle training tasks in Huntington's disease patients

INTRODUCTION

Huntington's disease (HD) patients have difficulty in swallowing, leading to aspiration pneumonia, which is a major cause of death. It seems possible that submental muscles that are crucial for preventing an escape of a bolus into the airway, are affected by HD, but no previous studies have investigated this.

OBJECTIVE

To assess surface electromyograph (sEMG) activity of submental muscles during swallowing and expiratory muscle training (EMT) tasks in HD patients in comparison to healthy volunteers.

METHODS

sEMG activities of submental muscles during saliva, water swallowing, EMT tasks performed at 25% and 75% of maximum expiratory pressure were recorded and normalised by the sEMG activity during an effortful swallow in 17 early to mid stage HD patients and 17 healthy volunteers.

RESULTS

sEMG activity was greater (p<0.05) during EMT tasks than saliva and water swallowing, but was not significantly different between groups for saliva, water swallowing and EMT at 25%. HD patients had lower sEMG activity for EMT at 75% (p<0.05).

CONCLUSION

Decreases in submental muscle activity were not evident in HD patients except during EMT at 75%. This suggests that relative submental muscle weakness is observed only during a high intensity task in early to mid stage HD patients.

Change in tongue morphology in response to expiratory resistance loading investigated by magnetic resonance imaging

[Purpose] The purpose of this study was to investigate the effect of expiratory resistance load on the tongue area encompassing the suprahyoid and genioglossus muscles. [Subjects] The subjects were 30 healthy individuals (15 males, 15 females, mean age: 28.9 years). [Methods] Magnetic resonance imaging was used to investigate morphological changes in response to resistive expiratory pressure loading in the area encompassing the suprahyoid and genioglossus muscles. Images were taken when water pressure was sustained at 0%, 10%, 30%, and 50% of maximum resistive expiratory pressure. We then measured tongue area using image analysis software, and the morphological changes were analyzed using repeated measures analysis of variance followed by post hoc comparisons. [Results] A significant change in the tongue area was detected in both sexes upon loading. Multiple comparison analysis revealed further significant differences in tongue area as well as changes in tongue area in response to the different expiratory pressures. [Conclusion] The findings demonstrate that higher expiratory pressure facilitates greater reduction in tongue area.

Dysphagia therapy in stroke: a survey of speech and language therapists

BACKGROUND

Dysphagia is common after stroke, leading to adverse outcome. There is a paucity of high-quality evidence for dysphagia therapy, thus making it difficult to determine the best approaches to treatment. Clinical decisions are often based on usual practice, however no formal method of monitoring practice patterns exists.

AIMS

To determine speech and language therapists' (SLTs) approaches to direct dysphagia therapy with stroke patients in the UK and Ireland.

METHODS & PROCEDURES

A 24-item questionnaire was developed, piloted and delivered in a web-based cross-sectional survey targeting all SLTs working with stroke patients in the UK and Ireland.

OUTCOMES & RESULTS

A total of 138 SLTs responded from a range of clinical settings and levels of experience. There was variation in the responses to all questions. Respondents reported treating patients a median of once a day, 3 days a week for 15 min. The most commonly recommended direct exercises were supervised swallow trials (recommended 'frequently or always' by 73%). Despite most respondents having access to an instrumental swallowing assessment, over half reported rarely or never conducting one before recommending exercises. Most (93%) did not use a protocol for systematically progressing patients' exercises and only 37% reported using standardized outcome measures.

CONCLUSIONS & IMPLICATIONS

This survey gives valuable insight into the direct dysphagia therapy practices of SLTs based in the UK and Ireland working in stroke. It highlights discrepancies between reported approaches and recommendations from existing evidence and clinical guidelines. The variation in responses indicates a need to develop a consensus statement and further research to guide practice.

Caracterização eletromiográfica da deglutição em indivíduos com e sem alterações clínicas

OBJETIVO: verificar a possibilidade de avaliação da deglutição por análise dos traçados eletromiográficos (EMG), em sujeitos com e sem alterações clínicas da deglutição; buscando características específicas voltadas para associação do exame clínico com a eletromiografia. MÉTODO: 39 sujeitos foram divididos em dois grupos: Grupo pesquisa (GP): 25 com alteração de deglutição; controle (GC): 14 sem alteração da deglutição. Equipamento Miotool 200/400 USB, quatro canais, eletrodos na região submental bilateralmente (supra-hióideos). Avaliado deglutição de saliva e cinco mililitros de água. Os registros EMG foram analisados por três juízes, após fornecidos os traçado EMG. Classificaram-se os registros em: normal (pico único) e alterados (mais de um pico, pico não definido, modificações no onset/offset). Utilizou-se o Teste de igualdade de duas proporções. RESULTADOS: obteve-se grande número de registros com deglutições não esperados em ambos os grupos e para os dois tipos de deglutição. Deglutição de saliva, com maior porcentagem em GP de registros com deglutição alterada, não houve diferença entre os grupos. Deglutição de saliva: GC apresentou registros variados, sem predomínio significativo; GP observou-se predomínio de mais de um pico e menor ocorrência de modificações no onset/offset. Deglutição de água: GC predomínio de pico único e menor ocorrência de mais de um pico; GP predomínio de pico único e menor ocorrência de pico não definido. CONCLUSÃO: análise dos traçados EMG não mostrou características específicas e diferenciadas para os grupos; não refletindo padrões que pudessem caracterizar os registros em sujeitos com e sem alterações clínicas da deglutição. Não foi possível definir correlação entre avaliação clínica e EMG da deglutição.

Effects of Mendelsohn maneuver on measures of swallowing duration post stroke

PURPOSE

The purpose of this pilot study was to determine whether intensive use of the Mendelsohn maneuver in patients post stroke could alter swallow physiology when used as a rehabilitative exercise.

METHOD

Eighteen outpatients between 6 weeks and 22 months post stroke were enrolled in this prospective study using a crossover design to compare 2 weeks of treatment with 2 weeks of no treatment. Each participant received an initial videofluoroscopic swallow study (VFSS) and an additional VFSS at the end of each week for 1 month for a total of 5 studies. During treatment weeks, participants received 2 treatment sessions per day performing Mendelsohn maneuvers with surface electromyography for biofeedback. Measures of swallowing duration, penetration/aspiration, residue, and dysphagia severity were analyzed from VFSS to compare treatment and no-treatment weeks.

RESULTS

Significant changes occurred for measures of the duration of superior and anterior hyoid movement after 2 weeks of treatment. Improvements were observed for duration of opening of the upper esophageal sphincter (UES), but results were not statistically significant. Measures of penetration/aspiration, residue, and dysphagia severity improved throughout the study, but no differences were observed between treatment and no-treatment weeks.

CONCLUSIONS

Intensive use of the Mendselsohn maneuver in isolation altered duration of hyoid movement and UES opening in this exploratory study. Results can guide future research toward improved selection criteria and exploration of outcomes. Larger numbers of participants and variations in treatment duration and intensity will be necessary to determine the true clinical value of this treatment.

Intra- and inter-rater reliability for analysis of hyoid displacement measured with sonography

PURPOSE

Anterior hyoid displacement is essential for efficient swallowing and is usually investigated with videofluoroscopy. Ultrasound offers a less expensive and noninvasive method of investigation. The present study investigated the viability of a novel method of quantifying hyoid displacement from sonograms using an anatomic reference point, through an evaluation of inter- and intra-rater reliability.

METHODS

Three raters reviewed the sonographic video sweeps of five discrete swallows from each of five participants for inter-rater reliability. The primary investigator measured each swallow on two occasions for intra-rater reliability. Electronic calipers were used to measure distances from a "rest" frame prior to the swallow of interest and a "maximal displacement" frame, at which the hyoid bone was at maximal anterior displacement during each swallow.

RESULTS

Single-measure intraclass correlation coefficient was high for inter-rater agreement at 0.86 for rest measures and 0.86 for maximal displacement. Intra-rater reliability was even higher at 0.95 for rest and 0.98 for maximal displacement.

CONCLUSIONS

These preliminary results suggest that by using a novel analysis approach involving an anatomic reference point, raters can achieve high agreement on measurement of position of hyoid at maximal displacement relative to rest.

High-resolution manometry of pharyngeal swallow pressure events associated with effortful swallow and the Mendelsohn maneuver

Effortful swallow and the Mendelsohn maneuver are two common strategies to improve disordered swallowing. We used high-resolution manometry (HRM) to quantify the effects of these maneuvers on pressure and timing characteristics. Fourteen normal subjects swallowed multiple, 5-ml water boluses using three techniques: normal swallow, effortful swallow, and the Mendelsohn maneuver. Maximum pressure, rate, duration, area integral, and line integral were determined for the velopharynx and tongue base. Minimum pressure, duration of pressure-related change, duration of nadir pressure, maximum preopening and postclosure pressure, area integral, and line integral were recorded for the upper esophageal sphincter (UES). Area and line integrals of the velopharyngeal pressure curve significantly increased with the Mendelsohn maneuver; the line integral increased with the effortful swallow. Preopening UES pressure decreased significantly for the Mendelsohn, while postclosure pressure tended to increase insignificantly for both maneuvers. UES area and line integrals as well as nadir UES pressure duration increased with both maneuvers. Maneuver-dependent changes were observed primarily at the velopharynx and UES. These regions are critical to safe swallowing, as the velopharynx provides positive pressure at the bolus tail while the UES allows a bolus to enter the esophagus without risk of regurgitation. Integrals were more responsive than maximum pressure or duration and should be investigated further.

The relationship between hyoid and laryngeal displacement and swallowing impairment

OBJECTIVES

Reduced range of hyoid and laryngeal movement is thought to contribute to aspiration risk and pharyngeal residues in dysphagia. Our aim was to determine the extent to which movements of the hyoid and larynx are correlated in the superior and anterior directions in swallowing, and whether movement range is predictive of penetration-aspiration or pharyngeal residue.

DESIGN

Prospective, single-blind study of penetration-aspiration and pharyngeal residue with objective frame-by-frame measures of hyoid and laryngeal excursion from videofluoroscopy.

SETTING

Tertiary hospital and rehabilitation teaching hospital.

PARTICIPANTS

Twenty-eight participants referred for videofluoroscopy: 13 women, aged 57-77; 15 men, aged 54-70. Individuals with known neurodegenerative diseases or prior surgery to the neck were excluded. Each swallowed three boluses of 40% w/v thin liquid barium suspension.

OUTCOMES

Two speech-language pathologists independently rated penetration-aspiration, vallecular and pyriform sinus residue. Cervical spine length, hyoid and laryngeal displacement were traced frame-by-frame. Predictive power was calculated.

RESULTS

Cervical spine length was significantly greater in men. Hyoid displacement ranged from 34-63% of the C2-4 distance. Arytenoid displacement ranged from 18-66%, with significantly smaller anterior displacement in men. Positive hyoid-laryngeal movement correlations in both axes were the most common pattern observed. Participants with reduced displacement ranges (≤ first quartile) and with abnormal correlation patterns were more likely to display penetration-aspiration. Those with reduced anterior hyoid displacement and abnormal correlation patterns had a greater risk of post-swallow pharyngeal residues.

CONCLUSIONS

It is difficult for clinicians to make on-line appraisals of the extent to which hyoid and laryngeal movement may be contributing to functional swallowing consequences during videofluoroscopy. This study suggests that it is most important for clinicians to discern whether reduced anterior displacement of these structures is contributing to a patient's swallowing impairment. Measures of structural displacement in thin liquid swallowing should be corrected for variations in participant height. Reductions in anterior hyoid and laryngeal movement below the first-quartile boundaries are statistically associated with increased risk for penetration-aspiration and post-swallow residues.