Movement of the hyoid bone and the epiglottis during swallowing in patients with dysphagia from different etiologies

Validity and Reliability of a Noninvasive Device for Measuring Laryngeal Movement During Swallowing

Background Laryngeal movement plays a crucial role in the process of swallowing. Peak velocity of laryngeal movement has been shown to be useful in predicting laryngeal penetration and aspiration. There is a growing need to accurately capture and quantify laryngeal movements during swallowing. Objective This research comprises two investigations that aim to verify and establish the reliability of a noninvasive device designed to measure laryngeal movement during swallowing. Methods In Step 1, one healthy male in his 30s underwent simultaneous videofluoroscopy (VF) examination and noninvasive device measurement. VF videos were employed to generate laryngeal movement curves using video analysis software. In Step 2, 19 healthy young adult men (20-39 years old) and 19 healthy older men (60-79 years old) were instructed to perform five saliva swallows each, with a noninvasive device placed against their necks. Results In Step 1, the comparison of laryngeal movement curves between VF and the noninvasive device exhibited almost perfect agreement for upward-downward movement, with less agreement noted for anterior-posterior movement. In Step 2, the reliability of the measurements of peak velocity and distance traveled in Nodomiru showed moderate to high reliability for single measurements (intraclass correlation coefficient (ICC) (1,1) = 0.598-0.855) and high reliability for the average of five measurements (ICC (1,5) = 0.694-0.967). Conclusions The results of this study suggest that it is possible to measure the upward-downward movement of the larynx in healthy men using a noninvasive device.

Tongue brushing enhances the myoelectric activity of the suprahyoid muscles in older adults: a six-week randomized controlled trial

Tongue brushing improves respiratory function in older adults. Considering connection between the respiratory-related and suprahyoid muscles, this study aimed to investigate whether tongue-brushing interventions can improve myoelectric activity during respiration. A six-week randomized controlled trial was conducted in Kitakyushu, Japan, with 50 participants aged ≥ 65 years. The participants were allocated to the intervention (tongue brushing with routine oral hygiene) or control (routine oral hygiene alone) groups. Surface electromyography (sEMG) was used to assess the myoelectric activity of the suprahyoid muscles during inhalation, exhalation, and forced vital capacity (FVC). A survey was conducted at baseline and the end of the follow-up period. Thirty-six participants were recruited for the analysis. The root mean squares (RMS) of sEMG during exhalation increased significantly at the end of the follow-up period compared with that at baseline in the intervention group [48.7 (18.0-177.5) vs. 64.9 (21.6-163.0), p = 0.001], but not in the control group. The generalized linear model revealed that the ratio of change in FVC was correlated with the change in the RMS of sEMG of the suprahyoid muscles during exhalation after adjusting for potential confounders. Tongue brushing enhances the myoelectric activity of the suprahyoid muscle.

Hyoid displacement during swallowing function for completely edentulous subjects rehabilitated with mandibular implant retained overdenture

BACKGROUND

Hyoid bone is attached to the mandible, tongue, larynx, temporal bone, and cervical spine via different types of muscles or ligaments. The tongue, mandible, and hyoid system play a crucial role in swallowing function. This within subject study aimed to evaluate the impact of mandibular implant overdentures on the displacement of the hyoid bones during the swallowing process.

METHODS

Twenty five healthy edentulous subjects were selected for participating in the study. New complete dentures were constructed for all the participants. Subsequently two dental implants were inserted in the canine regions of the participant's mandibular arch. In order to retain the mandibular prosthesis in place, ball attachments were incorporated into the mandibular dentures to convert them into implant overdentures. Using 10 ml of thin liquid bolus, videofluoroscopy swallowing examination was performed in three different oral conditions: without complete dentures (WCD), with complete denture (CDs), and with a mandibular implant overdenture (IODs). ANOVA with Bonferroni test was used to analyze the data in order to determine how the hyoid displacement varied throughout different oral conditions.

RESULTS

Compared to complete dentures, mandibular implant overdentures showed a significant decrease (P < 0.05) in both anterior hyoid displacement and duration of hyoid maximum anterior excursion (DOHMAE). However, there was a non-significant difference (P > 0.05) between the two oral circumstances in terms of superior hyoid displacement or duration for hyoid maximum elevation (DOHME). There is no penetration or aspiration for both complete denture and implant overdenture oral conditions.

CONCLUSION

Implant retained overdentures have a positive effect on hyoid displacement during swallowing of thin liquid bolus consistency relative to conventional complete dentures.

TRIAL REGISTRATION

Retrospectively registered (NCT06187181) 02/1/2024.

Residual effect of sequential 4-channel neuromuscular electrical stimulation evaluated by high-resolution manometry

BACKGROUND

High-resolution manometry (HRM) can quantify swallowing pathophysiology to evaluate the status of the pharynx. Sequential 4-channel neuromuscular electrical stimulation (NMES) was recently developed based on the normal contractile sequences of swallowing-related muscles. This study aimed to examine the effects of sequential 4-channel NMES for compensatory application during swallowing and to observe the residual effects after the application of NMES using HRM.

RESULTS

Sequential 4-channel NMES significantly improved the HRM parameters, with respect to the maximal pressure and area of the velopharynx (VP), maximal pressure and area of the mesopharynx (MP), and upper esophageal sphincter (UES) activation and nadir duration. Furthermore, the improvement in the pressure and area variables of the VP and MP showed a tendency to maintain even when measured after NMES, but there are no significant differences.

CONCLUSIONS

The present study suggests that the sequential 4-channel NMES application of the suprahyoid and infrahyoid muscles during swallowing improves the pressure, area, and time variables of the oropharynx, as measured by HRM, and it is likely that the effects may persist even after stimulation. Trial Registration Clinicaltrials.gov, registration number: NCT02718963 (initial release: 03/20/2016, actual study completion date: 06/24/2016, last release: 10/20/2020).

Chemoradiation to the submental muscles alters hyoid movement during swallowing in a rat model

Hyolaryngeal dysfunction is a commonly reported swallowing problem after chemoradiation treatment for head and neck cancer. The displacement of the hyolaryngeal complex during swallowing protects the airway and assists in opening the upper esophageal sphincter. Activation of the submental muscles, specifically the mylohyoid and geniohyoid muscles, is thought to facilitate movement of the hyoid. The purpose of this study was to determine if targeted radiation to the submental muscles given concurrently with chemotherapy alters hyolaryngeal displacement 1 mo after treatment. We hypothesized that chemoradiation treatment would result in abnormal patterns of hyoid movement compared with controls. Furthermore, we propose that these changes are associated with alterations in bolus size and discoordination of the jaw during drinking. Eighteen rats underwent either chemoradiation, radiation, or no treatment. Radiation treatment was targeted to submental muscles using a clinical linear accelerator given in 12 fractions of 4 Gy (3 days per week). Cycles of 1 mg/kg of cisplatin were administered concurrently each week of radiation. One month posttreatment, videofluoroscopy swallow studies (VFSS) were performed in self-drinking rats using a fluoroscope customized with a high-speed camera. The hyoid, jaw, and hard palate were tracked during swallowing from VFSS. Hyoid kinematics were analyzed from the start to the end of hyoid movement, and parameters were compared with bolus size and jaw movement. Significant differences in hyoid retraction parameters were found postchemoradiation. Alterations in the trajectory of hyoid motion during swallowing were observed. The findings demonstrate early changes in hyoid motion during swallowing associated with chemoradiation treatment.NEW & NOTEWORTHY Chemoradiation treatment for head and neck cancer can cause functional impairments in swallowing, which can adversely affect quality of life. This study provides new evidence that chemoradiation targeted to the submental muscles provokes early adaptations in hyoid movement during swallowing, which correlate with changes in bolus size. We also demonstrate a method for tracking the hyoid during swallowing in a rat model of chemoradiation injury.

A Large Cohort Analysis of Epiglottic Phenotypes and Pharyngeal Residue

OBJECTIVE

To describe the phenotypic characteristics of the epiglottis at rest and their impact on vallecular residue.

METHODS

Videofluoroscopic studies (VFSS) were pooled from 2 Laryngology practices, and Image J was used to measure epiglottic anatomic features at rest. Studies were rated by the MBSImp and presence of vallecular residue following swallow of thin and puree boluses. A conditional inference tree analysis was performed to isolate which epiglottic parameters were risk factors for presence of vallecular reside followed by logistic regression.

RESULTS

The majority of patients had a normal shaped epiglottis, followed by omega shape. The mean angle of the epiglottis from the hyoid was approximately 90°. Only abnormal epiglottic movement was associated with increased risk of residue for thin boluses (OR 35.09, CI 10.93-158.66, P < .001). However, in those with normal epiglottic movement, age >70 years old was associated with increased risk of residue (OR 3.98, CI 1.73-9.23, P = .001). For puree boluses, a normal or omega shaped epiglottis was associated with residue (OR 5.19, CI 2.41-11.51, P < .001), and this relationship was further modulated by increased distance of the epiglottic tip from the posterior pharyngeal wall. No other anatomic features of the resting epiglottis were associated with residue. Comorbidities potentially affecting swallow were infrequent in the cohort and were not associated with residue.

CONCLUSION

Abnormal epiglottic movement is associated with aspiration, and in this study we find that abnormal epiglottic movement increases the risk of vallecular residue and that older age is a risk factor for residue. The resting properties of the epiglottis do not appear to be associated with abnormal epiglottic movement or residue.

Clinical signs to predict the severity of dysphagia in Acute Ischemic Stroke patients

OBJECTIVES

In the current era, clinicians working in areas with limited and/or without facilities are only able to manage their patients based on clinical signs to detect dysphagia. This study assesses the performance of 5 simple clinical signs for predicting the severity of dysphagia.

METHODS

We systematically documented 5 targeted bedside clinical signs within 24 h after admission in 737 consecutive patients with acute stroke. We examined the median onset of each sign and calculated their ratios associated with severe dysphagia. The performance and significance of these special clinical signs were evaluated by further computation.

RESULTS

In total, 184 of 737 AIS patients were screened positive dysphagia by the modified V-VST. The 5 targeted bedside clinical signs were differed among the patients with and without dysphagia. Patients with serious dysphagia (n = 61,33.15%) showed higher positive percentages of larynx movement disorders than those classified as moderate (73.77% [60.99%-83.50%] vs 29.27% [21.82%-38.03%], p < 0.001). Logistic regression analyses conducted in the subsets confirmed larynx movement disorders as an independent predictor of dysphagia severity.

CONCLUSIONS

Larynx movement disorders is correlated with a higher probability of severe dysphagia as measured by the modified V-VST in AIS patients.

Effects of Head and Neck Alignment and Pharyngeal Anatomy on Epiglottic Inversion During Swallowing in Dysphagic Patients

The effects of head and neck alignment and pharyngeal anatomy on epiglottic inversion remain unclear. This study investigated the factors involved in epiglottic inversion, including head and neck alignment and pharyngeal anatomy, in patients with dysphagia. Patients with a chief complaint of dysphagia and who underwent videofluoroscopic swallowing study at our hospital from January to July 2022 were enrolled. They were divided into three groups based on the degree of epiglottic inversion as the complete-inversion (CI), partial-inversion (PI), and non-inversion group (NI) groups. Data were compared among the three groups; a total of 113 patients were analyzed. The median age was 72.0 (IQR: 62.0-76.0) years; 41 (36.3%) and 72 (63.7%) were women and men, respectively. There were in 45 (39.8%) patients in the CI, 39 (34.5%) in the PI, and 29 (25.7%) in the NI groups, respectively. Single-variable analysis revealed significant relation to epiglottic inversion of Food Intake LEVEL Scale score, penetration-aspiration score with 3-mL thin liquid bolus, epiglottic vallecula and pyriform sinus residue, hyoid position and displacement during swallowing, pharyngeal inlet angle (PIA), epiglottis to posterior pharyngeal wall distance, and body mass index. Logistic regression analysis with complete epiglottic inversion as the dependent variable revealed the X coordinate at maximum hyoid elevation position during swallowing and PIA as significant explanatory variables. These results suggest that epiglottic inversion is constrained in patients with dysphagia who have poor head and neck alignment or posture and a narrow pharyngeal cavity just before swallowing.

Evaluation of Swallowing Function in Relation to Oropharyngeal Dysphagia in Patients with Operated Unilateral Cleft Lip and Palate

OBJECTIVE

To determine the occurrence of oropharyngeal dysphagia (OD) signs and symptoms in patients with operated unilateral cleft lip and palate (CLP).

MATERIALS AND METHODS

This prospective study was conducted on 15 adolescents with operated unilateral CLP (CLP group) and 15 non-cleft volunteers (control group). Initially, the Eating Assessment Tool-10 (EAT-10) questionnaire was administered to subjects. OD signs and symptoms such as coughing, the sensation of choking, globus sensation, the need to clear the throat, nasal regurgitation, difficulties of bolus control multiple swallowing were evaluated by patient complaints and physical examination of swallowing function. Also, the Functional Outcome Swallowing Scale was used to determine the severity of the OD. Fiberoptic endoscopic evaluation of swallowing (FEES) with water, yogurt, and crackers was performed.

RESULTS

The prevalence of OD signs and symptoms based on patient complaints and physical examination of swallowing was low (range, 6.7 to 26.7%), and nonsignificant differences were observed between the groups for these parameters as well as for EAT-10 scores. According to the Functional Outcome Swallowing Scale findings, 11 of 15 patients with CLP were asymptomatic. Fiberoptic endoscopic evaluation of swallowing indicated that post-swallow pharyngeal wall residues with yogurt were significant in the CLP group with a prevalence of 53% ( P < 0.05), whereas differences between the groups in terms of cracker and water residues were nonsignificant ( P > 0.05).

CONCLUSION

OD in patients with repaired CLP was manifested mainly in the form of pharyngeal residue. However, it did not appear to cause significant increases in patient complaints compared with healthy individuals.

Kinematic mechanism of the rehabilitative effect of 4-channel NMES: post-hoc analysis of a prospective randomized controlled study

The sequential 4-channel neuromuscular electrical stimulation (NMES), based on the normal contractile sequences of swallowing-related muscles, is a new rehabilitative treatment. The objective of this study was to explore the mechanism of the rehabilitative effect of the 4-channel NMES using kinematic analysis of videofluoroscopic swallowing study (VFSS) data. For this post-hoc analysis, we included a subset of participants from the prospective randomized controlled study on the clinical effectiveness of the sequential 4-channel NMES compared with that of the conventional 2-channel NMES. Seventeen subjects (11 and six in the 4- and 2-channel NMES groups, respectively) were eligible for the kinematic analysis of VFSS data. The hyoid bone movement was analyzed by evaluating the distance and time parameters with four peak points (A, B, C, D). The 4-channel NMES group showed significant improvement in vertical distances (A-C), horizontal distance (A-B, A-C), time interval (A-B-C) and total time, compared with their pretreatment data. The 2-channel NMES group showed significant improvements in time interval (A-B); however, the Euclidean distance (A-D) and mean velocity of the Euclidean distance (A-C) were significantly decreased. When the two groups were directly compared, the 4-channel group showed significantly greater improvement in horizontal distance (A-B), Euclidean distance (A-D), time interval (A-B-C), and mean velocity the Euclidean distance (A-D). The results in this study suggest that the sequential 4-channel NMES might lead to the physiologic circular movement of the hyoid bone during swallowing, and therefore be an effective treatment for dysphagia.Trial registration: Clinicaltrials.gov, registration number: NCT03670498.

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

BACKGROUND

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

AIMS

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

MATERIALS & METHODS

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

RESULTS

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

CONCLUSION

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

Effects of transcutaneous neuromuscular electrical stimulation on post-stroke dysphagia: a systematic review and meta-analysis

Background

Dysphagia is one of the common complications after stroke. It is closely related to lung infection and malnutrition. Neuromuscular electrical stimulation (NMES) is widely used in the treatment of post-stroke dysphagia, but the evidence-based medical evidence of NMES is limited. Therefore, this study aimed to evaluate the clinical efficacy of NMES in patients with post-stroke dysphagia by systematic review and meta-analysis.

Methods

We searched the CNKI, Wanfang, VIP, SinoMed, PubMed, Embase, Cochrane Library, and Web of Science databases for all randomized controlled trials (RCTs) of NMES in the treatment of post-stroke dysphagia from the establishment of the database to 9 June 2022. The risk of bias assessment tool recommended by Cochrane and the GRADE method was used to assess the risk of bias and the quality of evidence. RevMan 5.3 was used for statistical analysis. Sensitivity and subgroup analyses were performed to evaluate the intervention effect more specifically.

Results

A total of 46 RCTs and 3,346 patients with post-stroke dysphagia were included in this study. Our meta-analysis showed that NMES combined with routine swallowing therapy (ST) could effectively improve swallowing function in Penetration-Aspiration Scale (MD = -0.63, 95% CI [-1.15, -0.12], P = 0.01), Functional Oral Intake Scale (MD = 1.32, 95% CI [0.81, 1.83], P < 0.00001), Functional Dysphagia Scale (MD = - 8.81, 95% CI [-16.48, -1.15], P = 0.02), the Standardized Swallowing Assessment (MD = -6.39, 95% CI [-6.56, -6.22], P < 0.00001), the Videofluoroscopic Swallow Study (MD = 1.42, 95% CI [1.28, 1.57], P < 0.00001) and the Water swallow test (MD = -0.78, 95% CI [-0.84, -0.73], P < 0.00001). Furthermore, it could improve the quality of life (MD = 11.90, 95% CI [11.10, 12.70], P < 0.00001), increase the upward movement distance of hyoid bone (MD = 2.84, 95% CI [2.28, 3.40], P < 0.00001) and the forward movement distance of hyoid bone (MD = 4.28, 95% CI [3.93, 4.64], P < 0.00001), reduce the rate of complications (OR = 0.37, 95%CI [0.24, 0.57], P < 0.00001). Subgroup analyses showed that NMES+ST was more effective at 25 Hz, 7 mA or 0-15 mA, and at courses ( ≤ 4 weeks). Moreover, patients with an onset of fewer than 20 days and those older than 60 years appear to have more positive effects after treatment.

Conclusion

NMES combined with ST could effectively increase the forward and upward movement distance of the hyoid bone, improve the quality of life, reduce the rate of complications, and improve the swallowing function of patients with post-stroke dysphagia. However, its safety needs to be further confirmed.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO, identifier: CRD42022368416.

Swallow Safety and Laryngeal Kinematics: A Comparison of Dysphagia Between Parkinson's Disease and Cerebrovascular Accident

BACKGROUND

Cerebrovascular accident (CVA) and Parkinson's disease (PD) are well established etiologies of dysphagia. However, differing physiological mechanisms underlying dysphagia may exist between these two causes. There have been limited investigations specifically comparing dysphagia between these two groups. Comparing dysphagia presentation in two different populations may improve clinical expectations, guide treatment approaches, and inform future research.

OBJECTIVE

This study examined the differences in presentation of dysphagia between PD and CVA. Dysphagia presentation, swallow safety, and laryngeal kinematics were compared between two clinical cohorts. What factors best predicted airway invasion in each group were explored.

METHODS

110 swallow studies of individuals with PD and CVA who were referred for swallowing evaluation were obtained. Each video was analyzed for quantitative dysphagia presentation using the Videofluoroscopic Dysphagia Scale (VDS), swallow safety using the Penetration-Aspiration scale, and kinematic timings of the laryngeal vestibule (time-to-laryngeal vestibule closure [LVC] and closure duration [LVCd]).

RESULTS

Frequencies of penetration or aspiration were similar between groups. The PD group displayed significantly greater pharyngeal stage swallow impairment than CVA, with more frequent reduced laryngeal elevation and increased vallecular residue. The CVA group displayed significantly greater oral stage impairment, with prolonged oral transit times. Time-to-LVC was significantly prolonged and was the strongest predictor of airway invasion in the PD group, but not for CVA.

CONCLUSION

Similar airway invasion rates for PD and CVA indicate the importance of screening for dysphagia in PD. Laryngeal kinematics as significant contributors to airway invasion in PD but not for CVA highlight the need for further research into these mechanisms and for targeted treatment approaches to dysphagia.

Swallow Safety and Laryngeal Kinematics: A Comparison of Dysphagia Between Parkinson's Disease and Cerebrovascular Accident

BACKGROUND

Cerebrovascular accident (CVA) and Parkinson's disease (PD) are well established etiologies of dysphagia. However, differing physiological mechanisms underlying dysphagia may exist between these two causes. There have been limited investigations specifically comparing dysphagia between these two groups. Comparing dysphagia presentation in two different populations may improve clinical expectations, guide treatment approaches, and inform future research.

OBJECTIVE

This study examined the differences in presentation of dysphagia between PD and CVA. Dysphagia presentation, swallow safety, and laryngeal kinematics were compared between two clinical cohorts. What factors best predicted airway invasion in each group were explored.

METHODS

110 swallow studies of individuals with PD and CVA who were referred for swallowing evaluation were obtained. Each video was analyzed for quantitative dysphagia presentation using the Videofluoroscopic Dysphagia Scale (VDS), swallow safety using the Penetration-Aspiration scale, and kinematic timings of the laryngeal vestibule (time-to-laryngeal vestibule closure [LVC] and closure duration [LVCd]).

RESULTS

Frequencies of penetration or aspiration were similar between groups. The PD group displayed significantly greater pharyngeal stage swallow impairment than CVA, with more frequent reduced laryngeal elevation and increased vallecular residue. The CVA group displayed significantly greater oral stage impairment, with prolonged oral transit times. Time-to-LVC was significantly prolonged and was the strongest predictor of airway invasion in the PD group, but not for CVA.

CONCLUSION

Similar airway invasion rates for PD and CVA indicate the importance of screening for dysphagia in PD. Laryngeal kinematics as significant contributors to airway invasion in PD but not for CVA highlight the need for further research into these mechanisms and for targeted treatment approaches to dysphagia.

Therapeutic Effect and Optimal Electrode Placement of Transcutaneous Neuromuscular Electrical Stimulation in Patients with Post-Stroke Dysphagia: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: To date, there is no conclusive evidence that transcutaneous neuromuscular electrical stimulation (TNMES) benefits patients with post-stroke dysphagia (PSD). In addition, the optimal TNMES electrode placement has not been well-established. This systematic review and meta-analysis were conducted to investigate these two research gaps. Methods: Five major databases were systematically searched for randomized controlled trials (RCTs) through January 2022. Effect sizes were computed using Hedges’ g statistic, which were then entered into the random-effects model to obtain pooled effect estimates. Results: Twenty-four RCTs met the eligibility criteria. On the improvement of swallowing function, TNMES alone was not superior to conventional swallowing therapies (CSTs); combined therapy of TNMES and CSTs significantly surpassed CSTs alone (standardized mean difference (SMD) = 0.91, 95% confidence interval (95% CI): 0.68 to 1.14, p < 0.0001; I2 = 63%). Moreover, significant pooled effect sizes were observed in subgroups with horizontal electrode placement above the hyoid bone (SMD = 0.94, 95% CI: 0.72 to 1.16; I2 = 0%) and horizontal electrode placement just above and below the hyoid bone (SMD = 0.87, 95% CI: 0.59 to 1.14; I2 = 0%). The largest pooled effect size was observed in the subgroup that individualized electrode placement according to dysphagia evaluation (SMD = 1.65, 95% CI: 0.38 to 2.91; I2 = 90%). Conclusion: TNMES should be used in combination with CSTs for PSD. Horizontal electrode placement should target suprahyoid muscles or both suprahyoid and thyrohyoid muscles.

Automated assessment of hyoid movement during normal swallow using ultrasound

BACKGROUND

The potential for using ultrasound by speech and language therapists (SLTs) as an adjunct clinical tool to assess swallowing function has received increased attention during the COVID-19 pandemic, with a recent review highlighting the need for further research on normative data, objective measurement, elicitation protocol and training. The dynamic movement of the hyoid, visible in ultrasound, is crucial in facilitating bolus transition and protection of the airway during a swallow and has shown promise as a biomarker of swallowing function.

AIMS

To examine the kinematics of the hyoid during a swallow using ultrasound imaging and to relate the patterns to the different stages of a normal swallow. To evaluate the accuracy and robustness of two different automatic hyoid tracking methods relative to manual hyoid position estimation.

METHODS & PROCEDURES

Ultrasound data recorded from 15 healthy participants swallowing a 10 ml water bolus delivered by cup or spoon were analysed. The movement of the hyoid was tracked using manually marked frame-to-frame positions, automated hyoid shadow tracking and deep neural net (DNN) tracking. Hyoid displacement along the horizontal image axis (HxD) was charted throughout a swallow, and the maximum horizontal displacement (HxD max) and maximum hyoid velocity (HxV max) along the same axis were automatically calculated.

OUTCOMES & RESULTS

The HxD and HxV of 10 ml swallows are similar to values reported in the literature. The trajectory of the hyoid movement and its location at significant swallow event time points showed increased hyoid displacement towards the peak of the swallow. Using an interclass correlation coefficient, HxD max and HxV max values derived from the DNN tracker and shadow tracker are shown to be in high agreement and moderate agreement, respectively, when compared with values derived from manual tracking.

CONCLUSIONS & IMPLICATIONS

The similarity of the hyoid tracking results using ultrasound to previous reports based on different instrumental tools supports the possibility of using hyoid movement as a measure of swallowing function in ultrasound. The use of machine learning to automatically track the hyoid movement potentially provides a reliable and efficient way to quantify swallowing function. These findings contribute towards improving the clinical utility of ultrasound as a swallowing assessment tool. Further research on both normative and clinical populations is needed to validate hyoid movement metrics as a means of differentiating normal and abnormal swallows and to verify the reliability of automatic tracking.

WHAT THIS PAPER ADDS

What is already known on this subject There is growing interest in the use of ultrasound as an adjunct tool for assessing swallowing function. However, there is currently insufficient knowledge about the patterning and timing of lingual and hyoid movement in a typical swallow. We know that movement of the hyoid plays an essential role in bolus transition and airway protection. However, manual tracking of hyoid movement is time-consuming and restricts the extent of large-scale normative studies. What this study adds We show that hyoid movement can be tracked automatically, providing measurable continuous positional data. Measurements derived from this objective data are comparable with similar measures previously reported using videofluoroscopy and of the two automatic trackers assessed, the DNN approach demonstrates better robustness and higher agreement with manually derived measures. Using this kinematic data, hyoid movement can be related to different stages of swallowing. Clinical implications of this study This study contributes towards our understanding of the kinematics of a typical swallow by evaluating an automated hyoid tracking method, paving the way for future studies of typical and disordered swallow. The challenges of image acquisition highlight issues to be considered when establishing clinical protocols. The application of machine learning enhances the utility of ultrasound swallowing assessment by reducing the labour required and permitting a wider range of hyoid measurements. Further research in normative and clinical populations is facilitated by automatic data extraction allowing the validity of prospective hyoid measures in differentiating different types of swallows to be rigorously assessed.

A Basic Study for Predicting Dysphagia in Panoramic X-ray Images Using Artificial Intelligence (AI)—Part 1: Determining Evaluation Factors and Cutoff Levels

Background: Dysphagia relates to quality of life; this disorder is related to the difficulties of dental treatment. Purpose: To detect radiographic signs of dysphagia by using panoramic radiograph with an AI system. Methods: Seventy-seven patients who underwent a panoramic radiograph and a videofluorographic swallowing study were analyzed. Age, gender, the number of remaining teeth, the distance between the tongue and the palate, the vertical and horizontal hyoid bone position, and the width of the tongue were analyzed. Logistic regression analysis was used. For the statistically significant factors, the cutoff level was determined. The cutoff level was determined by using analysis of the receiver operations characteristic (ROC) curve and the Youden Index. Results: A significant relationship with presence of dysphagia was only observed for the vertical hyoid bone position. The area under the curve (AUC) was 0.72. The cutoff level decided for the hyoid bone was observed to be lower than the mandibular border line. Conclusions: In cases where the hyoid bone is lower than the mandibular border line on a panoramic radiograph, it suggests the risk of dysphagia would be high. We will create an AI model for the detection of the risk of dysphagia by using the assessment of vertical hyoid bone position.

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).

Determining the Relationship Between Hyoid Bone Kinematics and Airway Protection in Swallowing

PURPOSE

Research remains equivocal regarding the links between hyoid movement and penetration-aspiration. The aims of this study were (a) to explore associations between hyoid parameters, laryngeal vestibule closure (LVC) parameters, and penetration-aspiration on thin liquids; and (b) to determine which of these parameters are the strongest predictors of penetration-aspiration.

METHOD

This study involved retrospective analysis of an existing videofluoroscopy data set, collected in 305 participants (152 males) with noncongenital/nonsurgical/non-oncological risk for dysphagia. We extracted data for six thin liquid swallows per participant, and obtained measures of hyoid movement (peak position, speed) and LVC (complete/incomplete, timing, duration). Resulting values were coded as typical/atypical relative to healthy reference data. Relationships were explored using chi-square tests and odds ratios (a) for the entire data set and (b) for the subset of data with complete LVC. Hierarchical logistic regression models determined the strongest predictors of penetration-aspiration.

RESULTS

Significant associations were found between penetration-aspiration and incomplete LVC, prolonged time-to-most-complete-LVC, short LVC duration, reduced anterior hyoid peak position, and reduced hyoid speed. Hyoid measures were also significantly associated with LVC parameters. In the first regression model, incomplete LVC and prolonged time-to-most-complete-LVC were the only significant predictors of penetration-aspiration. For cases with complete LVC, the only significant predictor was prolonged time-to-most-complete-LVC.

CONCLUSIONS

Although reduced anterior hyoid peak position and speed are associated with penetration-aspiration on thin liquids, these measures do not independently account for penetration-aspiration when considered in conjunction with measures of LVC. When identifying mechanisms explaining penetration-aspiration, clinicians should focus on LVC (complete/incomplete) and timeliness of LVC.

Hyoid bone movement during swallowing and mechanism of pharyngeal residue in patients with profound intellectual and multiple disabilities

OBJECTIVES

Dysphagia is linked to mortality risk among patients with profound intellectual and multiple disabilities (PIMD); the present study therefore aimed to clarify the characteristics of hyoid movements during swallowing and to examine the mechanism of dysphagia in patients with PIMD.

METHODS

A retrospective video fluoroscopic swallowing study was conducted on 43 patients with PIMD (mean age = 25.4; 25 males, 18 females) and 24 healthy adults (mean age = 44.3; 16 males, 8 females). The movements of the hyoid bone and mandible were tracked frame by frame in the video footage, and their range of movements and trajectories were analyzed.

RESULTS

Most patients showed atypical movement trajectories of the hyoid, such as insufficient anterior movement and increased range of mandibular downward movement, compared with normal adults. Moreover, the mechanism of dysphagia was revealed by structural equation modeling, indicating that insufficient anterior movement could lead to pharyngeal residue in the pyriform sinus.

CONCLUSION

The insufficient anterior movement of the hyoid could be caused by weak ventral suprahyoid muscles and atypical head and neck posture characteristic of patients with PIMD. It may be useful to predict pharyngeal residue from the range of hyoid movements and trajectories for the prevention of aspiration.

Compensatory Effects of Sequential 4-Channel Neuromuscular Electrical Stimulation for the Treatment of Acute, Subacute, and Chronic Dysphagia in a Prospective, Double-Blinded Randomized Clinical Trial

Background. The precise mechanism of 2-channel neuromuscular electrical stimulation (NMES) treatment is unknown, and controversy remains over its efficacy. The sequential 4-channel NMES was newly developed based on normal contractile sequences of swallowing-related muscles. Objective. To assess the clinical efficacy of sequential 4-channel NMES during swallowing. Methods. In this prospective RCT, 52 inpatients with dysphagia (acute, subacute, and chronic state) after stroke, brain tumor, or encephalitis were enrolled. Participants who underwent a videofluoroscopic swallowing study (VFSS) and clinical evaluation were enrolled and were randomly assigned to the 4-channel NMES or sham group. The 4-channel NMES and sham groups swallowed thin and honey-like fluids under NMES (sequential stimulation on suprahyoid and infrahyoid) and sham stimulation, respectively. The procedures were evaluated with the VFSS. Pre- and post-treatment evaluations were performed with the videofluoroscopic dysphagia scale (VDS), penetration-aspiration scale (PAS), Likert scale, and kinematic analysis. Results. The 4-channel NMES group showed significantly greater improvements than the sham group with respect to oral VDS, pharyngeal VDS, total VDS, and PAS (P < .05). Furthermore, the Likert scale for satisfaction, easiness, and discomfort for swallowing showed favorable results for the 4-channel NMES group (P < .05). In the kinematic analysis, the peak speed point, distance, and velocity of hyoid movement were significantly greater in the 4-channel NMES group (P < .05). Conclusions. Sequential 4-channel NMES activating the suprahyoid, thyrohyoid, and other infrahyoid muscles during swallowing showed significant clinical improvement with respect to VDS, PAS, and kinematic analysis. Therefore, sequential 4-channel NMES is a potential new functional electrical stimulation system for the treatment of dysphagia.

Hyoid Bone Tracking in a Videofluoroscopic Swallowing Study Using a Deep-Learning-Based Segmentation Network

Kinematic analysis of the hyoid bone in a videofluorosopic swallowing study (VFSS) is important for assessing dysphagia. However, calibrating the hyoid bone movement is time-consuming, and its reliability shows wide variation. Computer-assisted analysis has been studied to improve the efficiency and accuracy of hyoid bone identification and tracking, but its performance is limited. In this study, we aimed to design a robust network that can track hyoid bone movement automatically without human intervention. Using 69,389 frames from 197 VFSS files as the data set, a deep learning model for detection and trajectory prediction was constructed and trained by the BiFPN-U-Net(T) network. The present model showed improved performance when compared with the previous models: an area under the curve (AUC) of 0.998 for pixelwise accuracy, an accuracy of object detection of 99.5%, and a Dice similarity of 90.9%. The bounding box detection performance for the hyoid bone and reference objects was superior to that of other models, with a mean average precision of 95.9%. The estimation of the distance of hyoid bone movement also showed higher accuracy. The deep learning model proposed in this study could be used to detect and track the hyoid bone more efficiently and accurately in VFSS analysis.

Clinical effectiveness of the sequential 4-channel NMES compared with that of the conventional 2-channel NMES for the treatment of dysphagia in a prospective double-blind randomized controlled study

Background

To date, conventional swallowing therapies and 2-channel neuromuscular electrical stimulation (NMES) are standard treatments for dysphagia. The precise mechanism of 2-channel NMES treatment has not been determined, and there are controversies regarding the efficacy of this therapy. The sequential 4-channel NMES was recently developed and its action is based on the normal contractile sequence of swallowing-related muscles.

Objective

To evaluate and compare the rehabilitative effectiveness of the sequential 4-channel NMES with that of conventional 2-channel NMES.

Methods

In this prospective randomized case–control study, 26 subjects with dysphagia were enrolled. All participants received 2- or 4-channel NMES for 2–3 weeks (minimal session: 7 times, treatment duration: 300–800 min). Twelve subjects in the 4-channel NMES group and eleven subjects in the 2-channel NMES group completed the intervention. Initial and follow-up evaluations were performed using the videofluoroscopic dysphagia scale (VDS), the penetration-aspiration scale (PAS), the MD Anderson dysphagia inventory (MDADI), the functional oral intake scale (FOIS), and the Likert scale.

Results

The sequential 4-channel NMES group experienced significant improvement in their VDS (oral, pharyngeal, and total), PAS, FOIS, and MDADI (emotional, functional, and physical subsets) scores, based on their pretreatment data. VDS (oral, pharyngeal, and total) and MDADI (emotional and physical subsets) scores, but not PAS and FOIS scores, significantly improved in the 2-channel NMES group posttreatment. When the two groups were directly compared, the 4-channel NMES group showed significant improvement in oral and total VDS scores.

Conclusions

The sequential 4-channel NMES, through its activation of the suprahyoid and thyrohyoid muscles, and other infrahyoid muscles mimicking physiological activation, may be a new effective treatment for dysphagia.

Trial registration: clinicaltrial.gov, registration number: NCT03670498, registered 13 September 2018, https://clinicaltrials.gov/ct2/show/NCT03670498?term=NCT03670498&draw=2&rank=1.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12984-021-00884-6.

Lingual Exercise in Older Veterans With Dysphagia: A Pilot Investigation of Patient Adherence

Purpose Adherence is a concern in dysphagia management. Poor adherence with recommendations can negatively affect treatment efficacy and patient outcomes. For exercise-based therapies, low adherence can alter the dose of exercise delivered to the muscle, which can diminish impact of exercise. It has been established that low adherence is a problem in dysphagia treatments; however, relationships among levels of adherence and outcomes from exercise-based interventions have not been explored. Method In this retrospective pilot study, data were collected from a multicenter clinical demonstration program in the Veterans Affairs hospital system to examine the relationships between patient adherence with a device-facilitated lingual exercise regimen. Outcomes were compared pre- and posttreatment using a paired t test or Wilcoxon matched-pairs signed-ranks test, and relationships among adherence and outcome measures were evaluated using Pearson or Spearman rank correlation coefficients, as appropriate. Results Patient adherence was evenly distributed across participants: Adherence at the front sensor was 59.3% (SD = 28.2), ranging from 5.5% to 95.8%; the back sensor adherence was 55.9% (SD = 29.8), ranging from 1.1% to 97.2%. Maximum isometric pressure (MIP) generation, at both the front and back sensors, was increased from pre- to posttreatment (p < .0001, front; p = .008, back). Functional Oral Intake Scale (FOIS) scores were also significantly improved at the posttreatment time point as compared to baseline (p = .005). However, there were no significant correlations among adherence and outcome measures (front sensor adherence vs. ΔMIP, r = -.161, p = .342; back sensor adherence vs. ΔMIP, r = .002, p = .991; front sensor adherence vs. ΔFOIS, r = -.183, p = .279; back sensor adherence vs. ΔFOIS, r = -.160, p = .399). Conclusions These findings suggest that patient adherence with this lingual exercise program was not related to the increases in lingual pressure generation or improvement in functional oral intake observed in this cohort. These preliminary findings suggest the need for future, prospective, controlled, and randomized clinical trials to further investigate patient adherence with a lingual exercise program and related impacts of adherence on exercise dose and swallowing-related outcomes.

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.

Impact of CAD/CAM mandibular reconstruction on chewing and swallowing function after surgery for locally advanced oral cancer: A retrospective study of 50 cases

OBJECTIVE

Computer-aided design and computer-aided manufacturing (CAD/CAM) techniques are increasingly applied to mandibular reconstruction, but the superiority of this method in oral food intake has not been well established. Considering the extent of mandibular defects, this retrospective study was aimed to clarify the impact of CAD/CAM mandibular reconstruction on chewing and swallowing function after surgery for locally advanced oral cancer.

MATERIALS AND METHODS

We performed a retrospective review of 50 patients who had undergone segmental mandibulectomy with free flap reconstruction for locally advanced oral cancer. The patients' Functional Oral Intake Scale scores were measured at 3 months after surgery, and possible contributing factors including CAD/CAM mandibular reconstruction and the extent of mandibular defects for oral food intake were subjected to univariate analysis and multivariate logistic regression analysis.

RESULTS

Multivariate logistic regression analysis showed that CAD/CAM mandibular reconstruction was independently associated with good oral intake, whereas both anterior or extensive mandibular resection and glossectomy were also independently associated with poor oral intake after surgery.

CONCLUSION

The present study showed the positive impact of CAD/CAM mandibular reconstruction on chewing and swallowing function after surgery for locally advanced oral cancer for the first time.

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

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

Comparison of three different types of exercises for selective contractions of supra- and infrahyoid muscles

Several exercise methods, such as the Shaker exercise, tongue press exercise, chin tuck against resistance (CTAR) exercise, and submandibular push exercise, have been introduced to strengthen the muscles involved in swallowing. In this study, we compared the effectiveness of the CTAR, submandibular push, and Shaker exercises for the induction of selective supra- and infrahyoid muscle contractions using surface electromyography (EMG). This study is a prospective non-randomized controlled study. Twenty-five healthy subjects and 20 patients experiencing swallowing difficulty were enrolled. During the three different types of exercises, the root mean square (RMS) values of the sternocleidomastoid (SCM), suprahyoid (anterior belly of the digastric and mylohyoid muscles), and infrahyoid (sternothyroid and thyrohyoid muscles) muscles were analyzed using surface EMG. Differences in the activity of swallowing muscles among the three different exercises were analyzed using one-way repeated measured analysis of variance. In terms of both the maximum and mean RMS values of the suprahyoid muscle, the submandibular push exercise showed a larger RMS value than the CTAR and Shaker exercises in healthy subjects (p < 0.05). In terms of both the maximum and mean RMS values of the suprahyoid muscle, the Shaker exercise and submandibular push exercise showed a larger RMS value than the CTAR exercise in patients with swallowing difficulty (p < 0.05). The submandibular push exercise may be effective as a swallowing muscle exercise owing to its superiority in inducing selective contractions of the supra- and infrahyoid muscles. The CTAR and Shaker exercises are also effective in this regard.

The contractile patterns, anatomy and physiology of the hyoid musculature change longitudinally through infancy

All mammalian infants suckle, a fundamentally different process than drinking in adults. Infant mammal oropharyngeal anatomy is also anteroposteriorly compressed and becomes more elongate postnatally. While suckling and drinking require different patterns of muscle use and kinematics, little insight exists into how the neuromotor and anatomical systems change through the time that infants suckle. We measured the orientation, activity and contractile patterns of five muscles active during infant feeding from early infancy until weaning using a pig model. Muscles not aligned with the long axis of the body became less mediolaterally orientated with age. However, the timing of activation and the contractile patterns of those muscles exhibited little change, although variation was larger in younger infants than older infants. At both ages, there were differences in contractile patterns within muscles active during both sucking and swallowing, as well as variation among muscles during swallowing. The changes in anatomy, coupled with less variation closer to weaning and little change in muscle firing and shortening patterns suggest that the neuromotor system may be optimized to transition to solid foods. The lesser consequences of aspiration during feeding on an all-liquid diet may not necessitate the evolution of variation in neuromotor function through infancy.

Classification of Stroke Patients With Dysphagia Into Subgroups Based on Patterns of Submental Muscle Strength and Skill Impairment

OBJECTIVES

To identify and characterize subgroups of stroke patients with clinical signs of dysphagia, based on swallowing-related strength and skill impairments of the submental muscle group.

DESIGN

Prospective observational study.

SETTING

Inpatient rehabilitation centers and community dwellings.

PARTICIPANTS

Individuals (N=114), including stroke patients with dysphagia (n=55) and 2 control groups including myopathic patients with dysphagia (n=19) and healthy volunteers (n=40) were included in this study.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Novel clinical assessment of strength (force generation) and skill (spatial and temporal precision of muscle activation) of the submental muscle group during swallowing and nonswallowing behaviors, using surface electromyography and dynamometry.

RESULTS

Hierarchical cluster analysis revealed 4 clusters, which could be broadly characterized as cluster 1: intact strength and skill, cluster 2: poor strength and poor nonswallowing skill, cluster 3: poor strength, and cluster 4: poor strength and poor swallowing skill. Membership in cluster was significantly associated with medical diagnosis (P<.001). The majority of healthy and myopathic participants were assigned to clusters 1 and 3, respectively, whereas stroke patients were found in all 4 clusters. Skill outcome measures were more predictive of cluster assignment than strength measures.

CONCLUSIONS

Although healthy and myopathic participants demonstrated predominantly homogeneous swallowing patterns of submental muscle function within their etiology, several subgroups were identified within stroke, possibly reflecting different subtypes of swallowing function. Future research should focus on the nature and rehabilitation needs of these subtypes. Assessment of skill in swallowing may be an important but overlooked aspect of rehabilitation.

Humoral Influence of Repeated Lineage-Negative Stem/Progenitor Cell Administration on Articulatory Functions in ALS Patients

Amyotrophic lateral sclerosis (ALS) remains a fatal, neurodegenerative disease frequently leading to dysarthria and impaired swallowing. Better understanding of ALS pathophysiology is prompting the use of humoral cell therapies. Hence, a repeated cellular therapy was applied to ALS patients as an attempt to prevent speech deterioration. Autologous bone marrow-derived lineage-negative (Lin⁻) cells were intrathecally administered three times at six-week intervals to 42 sporadic ALS patients. Patients were examined for articulatory functions using subjective (VHI) and objective (FDA) scales. Selected trophic, proinflammatory factors and expression profiles of miRNA were measured in cerebrospinal fluid (CSF) and plasma by multiplex Luminex and q-PCR in different timepoints. Of the 42 patients who received the Lin⁻ cells, 6 showed improvement in articulatory functions, 27 remained stable, and 9 deteriorated after 18 weeks of therapy according to FDA scale. Clinical improvement was particularly evident by the 7^th day of each cell application and concerned better cough and swallow reflex, soft palate, laryngeal time, pitch, and volume. These results correlated with significant changes in the concentration of various trophic and proinflammatory factors and miRNA expression profiles. A multiple application of Lin⁻ cells proved to be safe and feasible. The repeated procedure can potentate a humoral effect and prevent speech deterioration. A short-lasting trophic effect of each Lin⁻ cells administration was observed on local and systemic level. However, further in-depth studies are necessary to sustain the beneficial effect.

Effectiveness of Different Application Parameters of Neuromuscular Electrical Stimulation for the Treatment of Dysphagia after a Stroke: A Systematic Review

Background: Dysphagia causes severe complications among people with a stroke. Physiotherapy allows the cure of this pathology, and among the tools it offers is neuromuscular electrical stimulation. However, this is a technique that has not been protocolized. Therefore, it was considered necessary to carry out a systematic review on the efficacy of the various parameters of application of the neuromuscular electrical stimulation in dysphagia generated after a stroke. Methods: A systematic search for publications was conducted in March 2020 in the Pubmed, Cinahl, Medline, Web of Science and Scopus databases, using as search terms: Electric stimulation therapy, Deglutition disorders and Stroke. Results: 21 articles were obtained in which the application of neuromuscular electrical stimulation was applied in isolation (n = 7) or in combination with other techniques such as strengthening exercises and manual therapy techniques (n = 14), with this second modality of treatment having greater benefits for patients. Conclusion: The greatest efficacy of this technique is reached when applied at 60-80 Hz, 700 μs of pulse duration, at the motor intensity threshold and in sessions of 20–30 min.

Effects of Neuromuscular Electrical Stimulation (NMES) Plus Upper Cervical Spine Mobilization on Forward Head Posture and Swallowing Function in Stroke Patients with Dysphagia

After a stroke, forward head posture occurs, resulting in swallowing dysfunction. Neuromuscular electrical stimulation (NMES) combined with upper cervical spine mobilization has demonstrated enhanced recovery of the swallowing function in stroke patients. This study investigated the therapeutic effects of NMES in conjunction with upper cervical mobilization in stroke patients with dysphagia. Thirty-four stroke patients were recruited (in a randomized controlled clinical trial) and divided into an experimental group (n = 17; NMES plus upper cervical spine mobilization) and a control group (n = 17; NMES plus sham mobilization). Forward head posture was measured by craniocervical flexion test (CCFT) and craniovertebral angle (CVA). Swallowing function was measured by variations in video fluoroscopic dysphagia scale (VDS) and penetration–aspiration scale (PAS) scores using the video fluoroscopic swallowing study (VFSS). All measurements were done at baseline and after four weeks of NMES plus mobilization. A significant increase was observed in CCFT, CVA, VDS (total VDS score, oral stage score, pharyngeal stage score), and PAS score in all variations in the experimental group. The CCFT, CVA, pharyngeal stage score, total VDS, and PAS score were significantly higher in the experimental group when compared to the control group. NMES plus upper cervical spine mobilization can be regarded as a promising method to improve swallowing function and forward head posture changes in stroke patients with dysphagia.

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

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

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.

The effect of preterm birth, recurrent laryngeal nerve lesion, and postnatal maturation on hyoid and thyroid movements, and their coordination in infant feeding

Movements of the hyoid and thyroid are critical for feeding. These structures are often assumed to move in synchrony, despite evidence that neurologically compromised populations exhibit altered kinematics. Preterm infants are widely considered to be a neurologically compromised population and often experience feeding difficulties, yet measuring performance, and how performance matures in pediatric populations is challenging. Feeding problems are often compounded by complications arising from surgical procedures performed to ensure the survival of preterm infants, such as damage to the recurrent laryngeal nerve (RLN) during patent ductus arteriosus correction surgery. Here, we used a validated infant pig model for infant feeding to test how preterm birth, postnatal maturation, and RLN lesion interact to impact hyoid and thyroid excursion and their coordination. We filmed infant pigs when feeding using videofluorscopy at seven days old (1-2 months human equivalent) and 17 days old (6-9 months human equivalent) and tracked movements of the hyoid and thyroid on both days. We found that preterm birth impacted the coordination between hyoid and thyroid movements, but not their actual excursion. In contrast, excursion of the two structures increased with postnatal age in term and preterm pigs. RLN lesion decreased thyroid excursion, and primarily impacted hyoid movements by increasing variation in hyoid excursion. This work demonstrates that RLN lesion and preterm birth have distinct, but pervasive effects on feeding performance in infants, and suggest that interventions targeted towards reducing dysphagia should be prescribed based off the etiology driving dysphagia, rather than the prognosis of dysphagia.

Epiglottic Retroflexion is a Key Indicator of Functional Recovery of Post-stroke Dysphagia

Objective

To evaluate the longitudinal changes of swallowing kinematics based on videofluoroscopic swallowing studies (VFSSs) in subacute stroke patients grouped according to the method of dietary intake.

Methods

Sixty-nine subacute stroke patients who had taken at least 2 successive VFSSs were included. Subjects were allocated into 3 groups according to the degree of swallowing function recovery—not improved group (tube feeding recommended to patients at both studies), improved group (tube feedings recommended initially to patients and oral feeding recommended at follow-up study), and well-maintained group (oral feeding at both studies recommended to patients). Initial VFSS was performed during the subacute stage of stroke, 1 to 12 weeks after the onset of stroke, and follow-up VFSS was performed at least once. Kinematic variables were calculated by two-dimensional motion analysis of multiple structures, including the hyoid bone, epiglottis, and vocal cord. Changes of kinematic variables were analyzed in serial VFSSs.

Results

At the initial VFSS, the well-maintained group showed significantly larger angles of epiglottic folding than the not improved group, while at the follow-up VFSS, the improved and the well-maintained groups showed significantly larger epiglottic folding angles than the not improved group. The distribution of epiglottic folding angles was in a dichotomous pattern, and each cluster was related to the swallowing function.

Conclusion

This study showed that improved epiglottic folding angles are associated with the recovery of the swallowing process and suitability for oral feeding among various kinematic variables in subacute stroke patients.

How a personalised transportable folding device for seating impacts dysphagia

PURPOSE

A personalised transportable folding device for seating (DATP) on a standard seat was developed by an occupational therapist at the Toulouse University Hospital Centre (patent no. WO 2011121249 A1) based on the hypothesis that the use of a seat to assist with better positioning on any chair during meals modifies the sitting posture and has an impact on cervical statics which increases the amplitude of movements of the axial skeleton (larynx and hyoid bone) and benefits swallowing. The aim of this work is to demonstrate that an improvement in sitting posture with the help of the DATP, through Hyoid bone motion, has an impact on the quality of swallowing in a dysphagic population which benefits from the device in comparison to a dysphagic population which does not benefit from the device after 1 month of care. The secondary endpoints concern the evaluation of the impact on other characteristics of swallowing, posture, the acceptability of the device and the quality of life.

METHODOLOGY

This is a randomised comparative clinical trial. The blind was not possible for the patients but the examiner who evaluated the outcome criterion was blinded to the group to which the patient belonged. The outcome criterion was the measurement of the hyoid bone movement during swallowing. The other criteria were collected during the videofluoroscopic examination of swallowing and by use of a questionnaire. Fifty-six (56) patients were included: 30 in the group without device (D-) and 26 in the group with the device (D+). All the patients benefited from a training course on seating. Only the D+ patients participated in this course where the use of the device was explained and the device was then kept for use at home for 1 month.

RESULTS

A significant improvement was noted in the postural criteria before and after use, in favour of a better posture for the two groups (p < 0.001) and more hyoid bone motion in the D+ group. The difference was significant in the bivariate analysis for horizontal movement (p = 0.04). After adjustment of potential factors of confusion, we noted a significant mean difference for the three distances in the D+ group in comparison to the D- group, of + 0.33 (95% CI [+ 0.17; + 0.48]) for horizontal movement, + 0.22 (95% CI [+ 0.03; + 0.40]) for vertical movement and + 0.37 (95% CI = [+ 0.20; + 0.53]) for horizontal movement. However, the other parameters, and notably the other swallowing markers were not significantly modified by the use of the device.

CONCLUSION

The personalised transportable folding device for seating developed to reduce dysphagia has an action on hyoid bone motion during swallowing. However, this positive effect on an intermediate outcome criterion of the quality of swallowing was not associated with an improvement in swallowing efficiency in the study population. The diversity of diseases with which the patients in this study were afflicted is a factor to be controlled in future studies with this device.

Achados videoendoscópicos da deglutição em diferentes consistências de alimento na Esclerose Lateral Amiotrófica

RESUMO Objetivo Este estudo teve por objetivo comparar os achados videoendoscópicos da deglutição orofaríngea em distintas consistências de alimento na Esclerose Lateral Amiotrófica (ELA). Método Estudo clínico retrospectivo com amostra de conveniência. Foram incluídos 20 indivíduos com diagnóstico de ELA e disfagia orofaríngea confirmada por avaliação clínica e objetiva de deglutição, independentemente do tipo, bulbar ou esquelética, e tempo de diagnóstico neurológico, 13 do sexo masculino e sete do sexo feminino, faixa etária variando de 34 a 78 anos, média de 57 anos. Foram analisados os achados da videoendoscopia de deglutição (VED) nas consistências líquida (N=18), líquida espessada (N=19) e pastosa (N=20) no volume de cinco ml. Os achados sobre escape oral posterior, resíduos faríngeos, penetração laríngea e/ou aspiração foram comparados nas três consistências de alimento e a análise estatística utilizou o teste ANOVA de Friedman. Resultados Não foi encontrada alteração na sensibilidade laríngea nessa população. Não houve diferença estatística significativa entre as consistências de alimento na presença de escape oral posterior, penetração e/ou aspiração. Houve diferença estatística significativa somente com resíduos faríngeos na consistência líquida espessada e pastosa na ELA. Conclusão Dentre os achados videoendoscópicos da deglutição na ELA, somente o resíduo faríngeo teve maior frequência na dependência da consistência de alimento.

Application of Automatic Kinematic Analysis Program for the Evaluation of Dysphagia in ALS patients

Dysphagia in amyotrophic lateral sclerosis (ALS) increases the risk of malnutrition, dehydration, and aspiration pneumonia. Kinematic analysis of videofluoroscopic swallowing study (VFSS) can provide detailed movement of the hyoid bone, revealing abnormalities of swallowing in ALS patients. We developed an automated kinematic analysis program (AKAP) that analyzes the trajectory of the hyoid bone via a visual tracking method. The aim of this study was to investigate the hyoid movement in ALS patients using AKAP and compare it with non-dysphagic subjects. Thirty ALS patients who underwent VFSS in Seoul National University Bundang Hospital between 2015 and 2017 were recruited. For comparison, 30 age-matched control subjects were also enrolled; the same swallowing study was conducted using thin fluid and yogurt. The hyoid bone movement was analyzed by evaluating the vertical and horizontal distances with four peak points (A, B, C, D), and the time of each point were also calculated. With respect to distance parameters, only vertical peak distance (distance between B, D points) during thin fluid swallowing was significantly decreased in ALS patients. (p = 0.038) With respect to temporal parameters, Time ABC, Time ABCD, and Duration C were significantly increased in ALS patients when swallowing both thin fluid and yogurt. (Time ABC p = 0.019, p = 0.002; Time ABCD p = 0.001, p = 0.004; Duration C p = 0.004, p = 0.025 respectively). This result revealed that dysphagia in ALS patient is caused by decreased velocity of hyoid bone movement due to the development of weakness in swallowing-related muscles. The parameters of kinematic analysis could be used to quantitatively evaluate dysphagia in motor neuron disease.

Impaired Movement Scaling and Reduced Synchrony with Vestibule Closure Characterize Swallowing in Severe Dysphagia

The contribution of hyoid and laryngeal movement deficits to penetration or aspiration in dysphagia is unclear, partly due to large variations in normal hyolaryngeal kinematics for swallowing. In healthy volunteers, laryngeal and hyoid kinematics relate to the requirements for laryngeal vestibule closure suggesting a central schematic control of movement magnitude and patterning for airway protection. Our first aim was to determine if patients with severe dysphagia showed evidence of an impaired swallowing schema, by examining if their kinematic measures were related to their hyolaryngeal space before swallow onset, and if hyolaryngeal movement synchrony for vestibule closure was disrupted. Our second aim was to determine the kinematic measures that predicted bolus penetration and aspiration in dysphagia. The methods included two-dimensional measures of the hyoid and laryngeal anterior and superior displacement and velocity, and the change in laryngeal vestibule area made from videofluoroscopic swallow recordings of 21 healthy volunteers and 21 patients with dysphagia on tube feeding secondary to the stroke or head and neck cancer. The results demonstrated that the patients did not adapt their hyolaryngeal movements during swallowing to their initial hyolaryngeal space. Further, none of the patients' measures of hyoid or laryngeal peak velocity timing were synchronized with vestibule closure, demonstrating a disorganized movement patterning. Laryngeal elevation peak velocity independently predicted penetration and aspiration. In conclusion, the central schema for swallowing patterning was disturbed, impairing the integration of kinematic actions for airway protection in severe dysphagia, while laryngeal peak elevation velocity predicted penetration and aspiration on patient swallows.

A Novel Method Using Kinesiology Taping for the Activation of Suprahyoid Muscles in Healthy Adults: A Preliminary Research

The suprahyoid muscles play a major role in safe swallowing in the pharyngeal phase. Therefore, it is clinically important to design a therapeutic approach for strengthening the suprahyoid muscles for safe and normal swallowing. This study aimed to investigate the activation of suprahyoid muscles by resistance training using kinesiology taping (KT). We enrolled 23 healthy adults. All participants performed saliva swallowing five times at 5 s intervals in three conditions (without KT, 50% stretch with KT, and 80% stretch with KT). KT in the I and reverse V shapes was pulled vertically from the hyolaryngeal complex to the sternum and medially from the superior surface of the clavicle, respectively. Another KT horizontally covered the hyolaryngeal complex to enhance the movement restriction of the hyolaryngeal complex during swallowing. Activation of the suprahyoid muscles during swallowing in the two conditions was measured using surface electromyography. In addition, a 0-10 numerical rating self-report scale was used to evaluate the required effort and the resistance felt during swallowing. Both KT 50% and 80% were significantly higher in surface electromyography (sEMG) mean value, peak value, required effort, and resistance felt during swallowing compared to normal swallowing (p < 0.05). In addition, KT 80% was significantly higher in sEMG value, peak value, required effort, and resistance felt during swallowing than KT 50% (p < 0.05). This study demonstrated that KT applied to the area under the hyolaryngeal complex improves activation of the suprahyoid muscle during swallowing. Therefore, KT applied as resistance during swallowing is considered to have therapeutic potential in dysphagia rehabilitation.

The Association of High Resolution Cervical Auscultation Signal Features With Hyoid Bone Displacement During Swallowing

Recent publications have suggested that high-resolution cervical auscultation (HRCA) signals may provide an alternative non-invasive option for swallowing assessment. However, the relationship between hyoid bone displacement, a key component to safe swallowing, and HRCA signals is not thoroughly understood. Therefore, in this work we investigated the hypothesis that a strong relationship exists between hyoid displacement and HRCA signals. Videofuoroscopy data was collected for 129 swallows, simultaneously with vibratory/acoustic signals. Horizontal, vertical and hypotenuse displacements of the hyoid bone were measured through manual expert analysis of videofluoroscopy images. Our results showed that the vertical displacement of both the anterior and posterior landmarks of the hyoid bone was strongly associated with the Lempel-Ziv complexity of superior-inferior and anterior-posterior vibrations from HRCA signals. Horizontal and hypotenuse displacements of the posterior aspect of the hyoid bone were strongly associated with the standard deviation of swallowing sounds. Medial-Lateral vibrations and patient characteristics such as age, sex, and history of stroke were not significantly associated with the hyoid bone displacement. The results imply that some vibratory/acoustic features extracted from HRCA recordings can provide information about the magnitude and direction of hyoid bone displacement. These results provide additional support for using HRCA as a non-invasive tool to assess physiological aspects of swallowing such as the hyoid bone displacement.

Posture-Dependent Dysphagia After Botulinum Toxin Type A Injection at Sternocleidomastoid in a Patient With Athetoid Cerebral Palsy

Cervical dystonia is a common issue in patients with athetoid cerebral palsy. Botulinum toxin injection to dystonic cervical muscles is a well-recognized treatment option, but it is known to be associated with dysphagia. Previously reported cases of dysphagia after botulinum toxin injection to the sternocleidomastoid muscle were related to the regional spread of toxin to the pharyngeal muscles. We report a unique case of posture-dependent dysphagia due to preactivation of the suprahyoid and infrahyoid muscles to compensate for impaired head stabilization by the weakened sternocleidomastoid muscle while swallowing. This case suggests a possible mechanism of dysphagia in patients with athetoid cerebral palsy.

Thyroid cartilage loci and hyoid bone analysis using a video fluoroscopic swallowing study (VFSS)

INTRODUCTION

Hyoid bone movement can be useful for diagnosing oropharyngeal dysphagia. In most clinical settings, the movement can be evaluated by a video fluoroscopic swallowing study (VFSS) that induces radiation exposure. In contrast with the hyoid bone, the thyroid cartilage is easily seen through the anterior neck surface. We hypothesized that the movement of thyroid cartilage correlates with hyoid bone movement in various axis and can be used as a parameter to evaluate swallowing. The purpose of this study was to investigate whether thyroid cartilage and hyoid bone movement were correlated and to collect basic data to determine if thyroid cartilage can be used as a parameter to evaluate swallowing.

METHODS

A total of 25 subjects were included, and the VFSS image with normal swallowing function was collected retrospectively. The VFSS image was analyzed by specially developed semi-automatic software. Laryngeal prominence and anterior-superior margins of the hyoid were automatically extracted during swallowing. Two-point sets of the loci during swallowing were obtained in all VFSS frames. The X-coordinates showed an anterior-posterior axis, and the Y-coordinates showed a superior-inferior axis. Pearson correlation coefficients for each X- and Y-coordinate component were computed.

RESULTS

X- and Y-coordinates of the thyroid cartilage and hyoid bones in all subjects showed movement in similar patterns, although each subject's movement differed. Pearson correlation coefficients of X- and Y-coordinate components of all subjects ranged from 0.611 to 0.981, which indicated that thyroid cartilage and hyoid bone movement was strongly correlated in anterior-posterior and superior-inferior axes, respectively.

CONCLUSION

We analyzed thyroid cartilage and hyoid bone movement using a specifically developed semi-automatic software and concluded that the movement of thyroid cartilage and hyoid bone was strongly correlated in anterior-posterior and superior-inferior axes, respectively, during swallowing. The present study implies that analysis of thyroid cartilage movement can be used as a parameter for swallowing evaluation.

Temporal characteristics of laryngeal penetration and aspiration in stroke patients

BACKGROUND

Despite the importance of understanding penetration-aspiration (PA) in patients with stroke, the pathophysiology of PA remains unclear.

OBJECTIVES

This study aimed to investigate the temporal characteristics of PA in post-stroke patients in terms of the timing of the PA event and hyolaryngeal incoordination.

METHODS

Fifty-eight swallows (38 stroke patients), showing PA when swallowing a thin liquid, were included. The timing of PA was classified kinematically as before or during the swallow. The movement sequence of vertical laryngeal elevation, horizontal hyoid excursion, and epiglottic rotation were compared with healthy controls. Spatiotemporal measurements, videofluoroscopic dysphagia scale parameters were compared between subgroups.

RESULTS

Thirteen swallows (22.4%) were classified as PA before the swallow and 45 were classified as PA during the swallow (77.6%). Among the PA during the swallow, 26 (57.8%) swallows exhibited abnormal sequences of hyolaryngeal movements and 19 (42.2%) swallows showed normal sequences of hyolaryngeal movements compared with healthy controls. The onset time of horizontal hyoid excursion (P = 0.028), the time to maximal horizontal hyoid excursion (P = 0.010), and maximal epiglottic rotation (P = 0.030) were significantly more delayed in the PA during the swallow group than in the PA before the swallow group. In the swallows with abnormal sequential movements, the onset of horizontal hyoid excursion occurred significantly later than the onset of epiglottic rotation (P < 0.001). Pyriform sinus residue was observed significantly more often in the swallows with abnormal sequences (P = 0.030) than in the swallows with normal sequences.

CONCLUSIONS

The timing of PA can be classified as before and during the swallow with significantly different temporal characteristics. The horizontal movement of hyoid is the most important factor associated with the pathophysiology of PA in stroke patients.

Differential kinematic features of the hyoid bone during swallowing in patients with Parkinson's disease

This study aimed to investigate spatiotemporal characteristics of the hyoid bone during swallowing in patients with Parkinson's disease (PD) and dysphagia. Spatiotemporal data of the hyoid bone was obtained from videofluoroscopic images of 69 subjects (23 patients with PD, 23 age- and sex-matched healthy elderly controls, and 23 healthy young controls). Normalized profiles of displacement/velocity were analyzed during different periods (percentile) of swallowing using functional regression analysis, and the maximal values were compared between the groups. Maximal horizontal displacement and velocity were significantly decreased during the initial backward (P = 0.006 and P < 0.001, respectively) and forward (P = 0.008 and P < 0.001, respectively) motions in PD patients compared to elderly controls. Maximal vertical velocity was significantly lower in PD patients than in elderly controls (P = 0.001). No significant difference was observed in maximal displacement and velocity in both horizontal and vertical planes between the healthy elderly and young controls, although horizontal displacement was significantly decreased during the forward motion (51st-57th percentiles) in the elderly controls. In conclusion, reduced horizontal displacement and velocity of the hyoid bone during the forward motion would be due to combined effects of disease and aging, whereas those over the initial backward motion may be considered specific to patients with PD.

Prevalence of dysphagia in patients with muscle tension dysphonia

Background

It is hypothesised that patients with muscle tension dysphonia have a high prevalence of dysphagia in comparison to normative values reported in the literature.

Methods

This prospective study included 44 subjects diagnosed with muscle tension dysphonia, based on symptoms and laryngoscopic findings, and 25 control subjects with no history of dysphonia and normal laryngeal examination findings. Demographic data included age, gender and smoking history. The aetiology of muscle tension dysphonia was classified as primary or secondary. Evaluation involved the Eating Assessment Tool (‘EAT-10’) questionnaire.

Results

Patients’ mean age was 45.93 ± 14.95 years, with a female to male ratio of 1.2:1. Fourteen patients had primary muscle tension dysphonia, while 30 had secondary muscle tension dysphonia. Among patients with secondary muscle tension dysphonia, Reinke's oedema was the most common aetiology. There was a significant difference in the prevalence of dysphagia between the study group and the control group (40.9 per cent vs 8 per cent respectively, p &lt; 0.05).

Conclusion

This study demonstrates a higher prevalence of dysphagia in patients with the presenting symptom of dysphonia and diagnosed with muscle tension dysphonia in comparison to subjects with no dysphonia.