Hyoid Movement Research Articles

Physiologic and anatomic determinants of hyoid motion during drug-induced sleep endoscopy

PurposeTo examine factors accounting for differences in hyoid motion during obstructive breathing events amongst obstructive sleep apnea (OSA) patients.MethodsThis was a prospective cohort study from June 2022 to October 2022. Patients with OSA undergoing evaluation for PAP alternative therapies with drug-induced sleep endoscopy with positive airway pressure titration (DISE-PAP). All patients underwent DISE-PAP and concurrent hyoid-focused ultrasound. DISE-PAP enabled measurement of airway physiology (flow, respiratory effort) and airway collapsibility (pharyngeal opening pressure, PhOP). Hyoid-ultrasound enabled hyoid bone movement during obstructive breathing. Respiratory effort was measured using a retro-epiglottic pressure-sensitive catheter. Hyoid position was measured using a standardized, awake, CT protocol. Regression analyses adjusted for age, race, sex, and BMI were performed to associate indices of respiratory effort and CT data with hyoid motion.ResultsOn average, the 26 patients in this cohort were older (63.9 ± 10.5 years), male (69%), overweight (29.6 ± 3.99 kg/m2), and with moderate-to-severe OSA (26.8 ± 10.4 events/hour). Greater respiratory effort was associated with increased hyoid motion (β [95% CI] = 0.034 [0.016,0.052], standardized β = 0.261,p = 0.0003). Higher hyoid position was associated with greater hyoid displacement (β [95% CI] = -0.20 [-0.38,-0.01], Standardized β = -0.57, p = 0.036).ConclusionOur data demonstrate that greater respiratory effort, higher hyoid position, and higher airway collapsibility, but not airflow, are associated with greater hyoid motion during obstructive breathing in DISE. These findings suggest that downward hyoid movement represents a compensatory response to upper airway obstruction. Further studies should investigate the vectors of hyoid motion to better understand its role in sleep-related airway collapse.

Effect of bolus property on swallowing dynamics in patients with dysphagia.

Modification of foods or liquids is commonly administered as part of dysphagia treatment. However, no consensus exists on the parameters for defining texture-modified food for patients with dysphagia. The aim of this study was to evaluate the effect of food/liquid material on swallowing physiology in patients with dysphagia and to discuss the optimal food choice for direct swallowing therapy. A total of 140 patients underwent a videofluoroscopic swallowing study using three test foods/liquids: 3 mL of mildly thick liquid (Thick liquid), jelly made of agar and polysaccharide (Jelly) and jelly made of pectin (Reset gel). Outcome measures of videofluoroscopic images, bolus transit time and hyoid movements were compared. The frequency of chewing movements was highest for Jelly, followed by Reset gel and Thick liquid. While the probability of oral residue was the highest for Reset gel, pharyngeal residue after swallowing was high for Thick liquid as compared to Jelly and Reset gel. Oral transit time and pharyngeal transit time for Thick liquid were significantly smaller than that for Jelly and Reset gel. Pharyngeal delay time was significantly smaller for Thick liquid than that for Jelly and Reset gel. There was no difference in hyoid elevation time and hyoid movement time among the conditions. Mildly thick liquid material may be optimal for patients with primarily oral motor function impairment and jelly, such as Reset gel, may be more suitable for patients with primarily pharyngeal motor function impairment or oral and pharyngeal coordinative motor function decline.

Muscle Tension Dysphagia: An Expanded Investigation of Clinical Presentations and Swallowing Kinematics.

This study retrospectively examined patient-reported symptoms, quality of life, and swallowing kinematics in individuals with presumed muscle tension dysphagia (MTDg). Twenty-six individuals met the inclusion criteria. Data were gathered from patient-reported outcome measures (PROs), symptomology, clinician reports of palpation, and hyolaryngeal and hyoid movements measured on a 20-ml thin liquid bolus during videofluoroscopic swallowing studies. All PROs were outside of typical limits, except for the Voice Handicap Index-10. Mean hyoid excursion was 1.52 cm (SD = 0.46, range: 0.76-2.43), and hyolaryngeal excursion was 0.77 cm (SD = 0.44, range: -0.42-1.68). A minority of participants (4%-19%) demonstrated atypical hyoid and/or hyolaryngeal excursion compared to the available normative reference value sets. Individuals demonstrated abnormalities in the clinical evaluation of the areas of palpation and reported perilaryngeal discomfort and symptoms of laryngeal hyperresponsiveness, with a negative impact on their quality of life across various PROs. Atypical hyoid and/or hyolaryngeal excursion during swallowing was rare when compared to available normative reference values. The clinical evaluation of MTDg may be enhanced by including components related to muscle tension and laryngeal hyperresponsiveness in order to differentiate MTDg from idiopathic functional dysphagia and lead the patient to the otolaryngology/speech-language pathology clinic for intervention and management.

Correlation between lesion location and dysphagia characteristics in post-stroke patients

ObjectiveTo assess the correlation between lesion location and swallowing function characteristics in post-stroke dysphagia (PSD) patients. Materials and methodsWe enrolled 133 PSD. The patients were divided into supratentorial and infratentorial stroke groups. We compared the measurements in the videofluoroscopic swallowing study (VFSS) with 3ml and 5 ml of diluted and thickened barium liquid data between supratentorial and brainstem stroke groups. We further compared the difference of VFSS measurements between patients with left hemispheric or right hemispheric lesions (further divided into unilateral hemispheric cortical and subcortical subgroups) and brianstem leison stroke group.To explore the lesion location's effect on different bolus volume, the VFSS measurements of 3ml and 5ml in each subgroups were compared respectively. The measurements of VFSS included the oral transit time, soft palate elevation duration, hyoid bone movement duration (HMD), UES opening duration, pharyngeal transit duration (PTD), stage of ansition duration, and laryngeal closure duration (LCD), the upper esophageal sphincter opening (UESO), hyoid bone superior horizontal displacement, and hyoid bone anterior horizontal displacement. General swallowing function was assessed using the Penetration Aspiration Scale (PAS) and Functional Oral Intake Scale (FOIS). We performed the paired t-test, Spearman's correlation, and Kruskal–Wallis test analysis to characterize the parameters among the groups. ResultsFifty-eight patients were assessed in the final analysis. The HMD (p = 0.019), PTD (p = 0.048) and LCD (p = 0.013) were significantly different between the supratentorial and brainstem lesion groups in 5ml volume. The HMD was significantly different (p = 0.045) between the left cortical and brainstem lesion groups. Significant differences in the HMD (p = 0.037) and LCD (p = 0.032) between the left subcortical and brainstem lesion groups were found in 5ml volume bolus. There was no group different when taking the 3ml volume bolus. Regarding the relationship between food bolus volume and swallowing functions, only the UESO demonstrated a significant difference in the subcortical lesion of the right hemisphere (p = 0.0032) compared the 3 ml and 5 ml volume bolus. The PTD demonstrated a moderate correlation with the PAS scores (r = 0.38, p = 0.0044). The HMD (r = 0.32, p = 0.018) and LCD (r = 0.29, p = 0.039) demonstrated weak correlations with the PAS scores. We did not identify any correlation between the VFSS parameters and FOIS scores in each subgroup level. ConclusionThe PSD with brainstem lesion shows more sever dysfunction in the pharyngeal phases. The left hemisphere was engaged in both the oral and pharyngeal phases. Lesions in the bilateral cortical, subcortical, and brainstem regions may impair sensory input.

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.

Hyoid Bone Movement During Swallowing in Female Thyroidectomy Patients: A Kinematic Ultrasound Study.

The aim of this study was to investigate the measures of displacement, time and velocity of hyoid bone movement in female thyroidectomy patients. Fifty-eight ultrasound videos of 29 women during swallowing were analyzed. The sample was divided into experimental group (EG), composed of 12 women following total or partial thyroidectomy; and control group (CG) of 17 healthy women. The kinematic measures of displacement, time and velocity of hyoid bone displacement were tracked during swallowing of 10ml of liquid (water) and 10ml of thickened liquid (honey) in both groups for comparisons. Additional analysis included bolus consistency effect and relationship with clinical characteristics. Ultrasound videos were analyzed according to a standardized protocol using ImageJ software. Displacement, time and velocity of hyoid movement during swallowing of 10ml of liquid or thickened liquid were not statistically different between female thyroidectomy patients and healthy women. There is no bolus consistency effect on kinematic measures in both groups, but among thyroidectomy patients, velocity of hyoid bone movement is significantly faster in those with swallowing complaints.

Diagnostic value of a deep learning-based hyoid bone tracking model for aspiration in patients with post-stroke dysphagia.

Hyoid bone movement is potentially related to aspiration risk in post-stroke dysphagia (PSD) patients but is difficult to assess quantitatively. This study aimed to measure the distance of hyoid bone movement more efficiently and accurately using a deep learning model and determine the clinical usefulness of the model in PSD patients. This study included 85 patients with PSD within 6 months from onset. Patients were grouped into an aspiration group (n = 35) and a non-aspiration group (n = 50) according to the results of a videofluoroscopic swallowing study. Hyoid bone movement was tracked using a deep learning model constructed with the BiFPN-U-Net(T) architecture. The maximum distance of hyoid bone movement was measured horizontally (H max), vertically (V max), and diagonally (D max). Compared with the non-aspiration group, the aspiration group showed significant decreases in hyoid bone movement in all directions. The area under the curve of V max was highest at 0.715 with a sensitivity of 0.680 and specificity of 0.743. The V max cutoff value for predicting aspiration risk was 1.61 cm. The success of oral feeding at the time of discharge was significantly more frequent when hyoid movement was equal to or larger than the cutoff value although no significant relationship was found between hyoid movement and other clinical characteristics. Hyoid bone movement of PSD patients can be measured quantitatively and efficiently using a deep learning model. Deep learning model-based analysis of hyoid bone movement seems to be useful for predicting aspiration risk and the possibility of resuming oral feeding.

Bedside Ultrasound to Identify and Predict Severity of Dysphagia Following Ischemic Stroke: Human Versus Artificial Intelligence

Dysphagia is a significant ischemic stroke complication that can lead to aspiration. Identification of at-risk patients can be logistically difficult and costly. Researchers investigated whether quantitative ultrasound assessment of hyoid bone movement during induced swallowing would predict failure of videofluoroscopy (VFS) or fiberoptic endoscopic evaluation of swallowing (FEES), as determined by a penetration-aspiration scale (PAS) score. Additionally, ability of a machine learning (ML) algorithm to predict PAS success or failure from real-time ultrasound video recordings was assessed. A prospective, single-blinded, observational pilot study was conducted from June 2019 through March 2020 at a comprehensive stroke center on a convenience sample of patients admitted with diagnosis of acute ischemic stroke undergoing VFS or FEES as part of dysphagia assessment. Researchers performed a midsagittal airway ultrasound during swallowing in patients receiving an objective swallowing assessment by speech language pathologists who were blinded to ultrasound results. Sonologists measured hyoid bone movement, and researchers then constructed an ML algorithm designed for real-time video analysis using a long short-term memory network with an embedded VGG16 convolutional neural network. Videos from 69 patients were obtained with their respective PAS results. In total, 90% of available videos were used for algorithm training. After training, the ML algorithm was challenged with the 10% previously unseen videos and then compared with PAS outcomes. Statistical analysis included logistic regression and correlation matrix testing on human ultrasound measurements. Cohen's κ was calculated to compare deep learning algorithm prediction with PAS results. Measurement of hyoid bone elevation, forward displacement, total displacement and mandible length was unable to predict PAS assessment outcome (p values=0.36, 0.13, 0.11 and 0.32, respectively). The ML algorithm showed substantial agreement with PAS testing results for predicting test outcome (κ=0.79; 95% confidence interval: 0.52-1.0) CONCLUSION: Manual ultrasound measurement of hyoid movement during swallowing in stroke patients failed to predict PAS swallowing results. However, an ML algorithm showed substantial agreement with PAS results despite a small data set, which could greatly improve access to dysphagia assessment in the future.

Effect of fluid viscosity on the biomechanical sequence of oropharyngeal swallowing in healthy males

Objective: To confirm the effect of fluid with different viscosity on the normal biomechanical sequence of oropharyngeal swallowing in healthy males. Methods: Fifteen healthy male subjects [(27.7±1.8) years old] were recruited from November 2011 to February 2012 and instructed to swallow 15 ml of water (W), nectar-like fluid (N), and honey-like fluid (H) in an upright sitting position. The sensing system was consisted of tongue pressure sensor sheet, bend sensor, surface electrodes and microphone. They were used to monitor tongue pressure, hyoid activity, surface electromyography (EMG) of swallowing-related muscles and swallowing sound, respectively. The swallowing sound was chosen as the reference time. The significance of biomechanical sequence of structural events was determined by repeated-measures analysis of variance (ANOVA). Results: When swallowing liquid of any consistency, hyoid premotor and suprahyoid muscle electromyography (EMG) appeared synchronously (P>0.05), followed by the simultaneous appearances of hyoid rapid movement, peak time of suprahyoid muscle EMG, onset of infrahyoid muscle EMG, and anterior tongue pressure production (P>0.05). The peak time of infrahyoid muscle EMG was very close to the peak time of anterior tongue pressure (P>0.05), and both of them were earlier than the time that the hyoid reaching the highest position (P<0.05). At last, the time that the hyoid departing the highest position was synchronized with the disappearances of suprahyoid muscle EMG, infrahyoid muscle EMG, and tongue pressure (P>0.05). The tongue pressure production and peak time of tongue pressure arose from anterior to posterior along the midline of hard palate during normal swallowing, with the significances for tongue pressure production between the anterior site and the middle site (W: P=0.035, N: P=0.027, H: P=0.013) as well as the anterior site and the posterior site (W: P<0.001, N: P<0.001, H: P<0.001), while the appearance and peak time of the circumferential tongue pressure were very close (P>0.05). The increase of fluid viscosity did not affect the biomechanical sequence of the above structural physiological movements during normal swallowing. There were statistically significant differences between the hyoid premotor and the onset of suprahyoid muscle EMG when swallowing the honey-like liquid [(-1.03±0.47) and (-0.90±0.50) s] and water[(-0.87±0.32) and (-0.74±0.31) s] (P<0.001). Among the delayed structural events, except for the onset of infrahyoid muscle EMG and the tongue pressure production on the anterior site (P>0.05), the occurrences of all the parameters in swallowing honey-like fluid were significantly later than those in swallowing water (onset of hyoid rapid movement, P=0.007; time of hyoid reaching the highest position, P=0.034; time of hyoid departing the highest position, P=0.041; offset of hyoid movement, P=0.035; peak time of suprahyoid muscle EMG: P=0.040; offset of suprahyoid muscle EMG, P=0.014; peak time of infrahyoid muscle EMG: P=0.042; offset of infrahyoid muscle EMG, P=0.028; peak time of Ch.1: P=0.045; offset of Ch.1: P=0.012; onset of Ch.2: P=0.038; peak time of Ch.2: P=0.009; offset of Ch.2: P=0.034; onset of Ch.3: P=0.043; peak time of Ch.3: P=0.011; offset of Ch.3: P=0.026;onset of Ch.4: P=0.040; peak time of Ch.4: P=0.038; offset of Ch.4: P=0.033; onset of Ch.5: P=0.046; peak time of Ch.5:P=0.028; offset of Ch.5: P<0.001), but not for those between nectar-like fluid and honey-like fluid (P>0.05). Conclusions: The alteration of fluid viscosity did not affect healthy male biomechanical sequence of tongue, hyoid and swallowing-related muscles during normal swallowing. The biomechanics of the oropharyngeal structures is physiologically regulated with the alteration of fluid viscosity to ensure swallowing safely and smoothly.

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.

Temporal Characteristics of Penetration and Aspiration in Patients with Severe Dysphagia Associated with Lateral Medullary Syndrome.

To assess the severity and timing of penetration and aspiration (PA) of severe dysphagia after lateral medullary syndrome (LMS) and its association with temporal characteristics. We performed videofluoroscopic swallowing studies(VFSS) in 48 patients with LMS and severe dysphagia and 26 sex- and age-matched healthy subjects. The following temporal measures were compared between groups: velopharyngeal closure duration (VCD); hyoid bone movement duration (HMD); laryngeal vestibular closure duration (LCD); upper esophageal sphincter (UES) opening duration (UOD); stage transition duration (STD) and the interval between laryngeal vestibular closure and UES opening (LC-UESop). The association between temporal measures and Penetration-Aspiration Scale (PAS) scores was analyzed. Differences in timing measures were compared between subgroups (safe swallows, and swallows with PA events during and after the swallow). PAS scores ≥ 3 were seen in 48% of swallows (4% occuring before,35% occurred during and 61% after the swallow) from the LMS patients. Significantly longer STD and LC-UESop were found in the patients compared to the healthy subjects (p < 0.05). Significant negative correlations with PA severity were found for HMD, LCD, and UOD. Short UOD was the strongest predictor with an area under the receiver-operating-characteristic curve of 0.66. UOD was also significantly shorter in cases of PA after the swallow (p < 0.01). Patients with LMS involving severe dysphagia exhibit a high frequency of PA (mostly during and after swallowing). PA events were associated with shorter UOD, HMD, and LCD. Notably, shortened UOD appears to be strongly associated with PA.

Findings of a videofluoroscopic swallowing study in patients with dysphagia.

Swallowing examination is crucial in patients with dysphagia. We aimed to compare qualitative and quantitative videofluoroscopic swallowing study (VFSS) results to provide reference for standardizing quantitative parameters. In total, 117 patients with dysphagia were included, 38 with Parkinson's disease and 39 and 40 in convalescence following cerebral hemorrhage and infarction. VFSS was both qualitatively and quantitatively analyzed. A significant difference of Oral transit time was found between the oral motor function grades (p < 0.001), also was swallowing reaction times found between swallowing reaction duration grades (p < 0.001), and soft palate lift duration between the soft palate lift grades (p < 0.001). Superior hyoid bone movement (p < 0.001), anterior hyoid bone movement (p < 0.001), hyoid pause time (p < 0.001), and hyoid movement duration (p = 0.032) had significant differences between the hyoid laryngeal complex movement grades, as did the pharyngeal cavity transit time among the cricopharyngeal muscle opening duration grades (p < 0.001). The laryngeal vestibule closure duration differed among the glottic closure grades (p < 0.001). No statistically significant difference in upper esophageal sphincter opening diameter (p = 0.682) or duration (p = 0.682) among the cyclopharyngeal muscle opening duration grades. The pharyngeal area at rest did not significantly differ among the different vallecular residue (p = 0.202) and pyriform sinus residue (p = 0.116) grades. Several quantitative parameters can reflect the swallowing assessment process well. Further optimization of quantitative parameters is recommended.

Modulation of reflex responses of the anterior and posterior bellies of the digastric muscle in freely moving rats.

Chewing and licking are primarily activated by central pattern generator (CPG) neuronal circuits in the brainstem and when activated trigger repetitive rhythmic orofacial movements such as chewing, licking and swallowing. These CPGs are reported to modulate orofacial reflex responses in functions such as chewing. This study explored the modulation of reflex responses in the anterior and posterior bellies (ant-Dig and post-Dig, respectively) of the digastric muscle evoked by low-intensity trigeminal stimulation in conscious rats. The ant-Dig and post-Dig reflexes were evoked by using low-intensity electrical stimulation applied to either the right or left inferior alveolar nerve. Peak-to-peak amplitudes and onset latencies were measured. No difference was observed between threshold and onset latency for evoking ant-Dig and post-Dig reflexes, suggesting that the latter was also evoked disynaptically. The peak-to-peak amplitude of both reflexes was significantly reduced during chewing, licking and swallowing as compared to resting period and was lowest during the jaw-closing phase of chewing and licking. Onset latency was significantly largest during the jaw-closing phase. Inhibitory level was similar between the ant-Dig and post-Dig reflex responses and between the ipsilateral and contralateral sides. These results suggest that both the ant-Dig and post-Dig reflex responses were significantly inhibited, probably due to CPG activation during feeding behaviours to maintain coordination of jaw and hyoid movements and hence ensure smooth feeding mechanics.

The Application of Ultrasound to Quantify Hyoid Motion During Drug-Induced Sleep Endoscopy.

The significance of hyoid dynamics in OSA pathophysiology remains unclear. Drug-induced sleep endoscopy (DISE) is often used for evaluating patients intolerant to positive airway pressure (PAP) therapy. We performed DISE with concurrent hyoid-focused ultrasonography to quantify hyoid dynamics during obstructive and non-obstructive breathing. A cross-sectional analysis from a prospective cohort of patients undergoing DISE with PAP titration (DISE-PAP) and hyoid-focused ultrasound was conducted. Hyoid ultrasound was performed during obstructive breathing, and non-obstructive breathing after PAP administration. Motion was quantified by generating displacement curves based on echo-tracking hyoid movement. The image analysis protocol for quantifying hyoid displacement was performed independently by two researchers, and reliability of measures was assessed. Univariate and multivariate regressions were performed for various clinical data and hyoid displacement during obstructive breathing. Twenty patients met inclusion criteria. On average, the cohort was male (75%), elderly (65.9 ± 10 years), overweight (29.3 ± 3.99 kg/m2 ), and with moderate-to-severe OSA (29.3 ± 12.5 events/h). Mean hyoid displacement during obstructive breathing was 5.81 mm (±3.48). In all patients, hyoid displacement decreased after PAP administration (-3.94 mm [95% CI: -5.10, -2.78]; p < 0.0001). Inter-rater reliability for measures of hyoid displacement was excellent. After multivariate regression, hyoid displacement at baseline was associated with higher AHI (β [95% CI] = 0.18 [0.03, 0.33], p = 0.020). During DISE, hyoid displacement is greater during obstructive breathing with significant variability amongst patients. Further, these ultrasonographic measurements had excellent intra- and inter-rater reliability. Additional, larger studies are needed to understand contributors to hyoid mobility. 4 Laryngoscope, 133:3221-3227, 2023.

Identification of muscle activities involved in hyoid bone movement during swallowing using computer simulation

ABSTRACT It is difficult to clarify the activity of swallowing-related muscles and the movement of organs. To represent the relationship between muscle activity and organ movement, a numerical simulator that reflects muscle contraction is necessary. However, no continuum organ models can identify and reflect muscle activity. In this study, a novel method was developed for obtaining the time change in the activities of all muscles involved in hyoid excursion. An organ model was developed based on four-dimensional computed tomography (4DCT) images acquired using a 320-column area detector CT, and the organ movement was analysed using a particle method. To identify the muscle activity, an evaluation function was defined and calculated considering the errors of velocities and positions of the hyoid bone, and the muscle activities to minimise the evaluation function were calculated using gradient descent. The results showed that the hyoid movement represented by the simulation model and the objective movement obtained from 4DCT images were in good agreement. The identified muscle activities were discussed through a comparison with the literature on electromyography measurements and the results of simulations using other methods. The proposed continuum organ model with muscles was considered able to clarify both muscle activity and organ movement.

Changes in tongue morphology predict responses in pharyngeal patency to selective hypoglossal nerve stimulation.

The major goal of the study was to determine whether changes in tongue morphology under selective hypoglossal nerve therapy for obstructive sleep apnea were associated with alterations in airway patency during sleep when specific portions of the hypoglossal nerve were stimulated. This case series was conducted at the Johns Hopkins Sleep Disorders Center at Johns Hopkins Bayview Medical Center. Twelve patients with apnea implanted with a multichannel targeted hypoglossal nerve-stimulating system underwent midsagittal ultrasound tongue imaging during wakefulness. Changes in tongue shape were characterized by measuring the vertical height and polar dimensions between tongue surface and genioglossi origin in the mandible. Changes in patency were characterized by comparing airflow responses between stimulated and adjacent unstimulated breaths during non-rapid eye movement sleep. Two distinct morphologic responses were observed. Anterior tongue base and hyoid-bone movement (5.4 [0.4] to 4.1 [1.0] cm (median and [interquartile range]) with concomitant increases in tongue height (5.0 [0.9] to 5.6 [0.7] cm) were associated with decreases in airflow during stimulation. In contrast, comparable anterior hyoid movement (tongue protrusion from 5.8 [0.5] to 4.5 [0.9] cm) without significant increases in height (5.2 [1.6] to 4.6 [0.8] cm) were associated with marked increases in airflow during sleep. Tongue protrusion with preservation of tongue shape predicted increases in patency, whereas anterior movement with concomitant increases in height were associated with decreased pharyngeal patency. These findings suggest that pharyngeal patency can be best stabilized by stimulating lingual muscles that maintain tongue shape while protruding the tongue, thereby preventing it from prolapsing posteriorly during sleep. Fleury Curado T, Pham L, Otvos T, etal. Changes in tongue morphology predict responses in pharyngeal patency to selective hypoglossal nerve stimulation. J Clin Sleep Med. 2023;19(5):947-955.

Application of Real-time Submental Ultrasonography to Assess Swallowing.

Speech and swallowing dysfunction are common problems in head-and-neck cancer (HNC) survivors. Ultrasound (US) is a good method to assess suprahyoid muscles and hyoid bone movement, and it can provide valuable information on swallowing. The aims of this study were to measure the biometry of the supraglottic muscles and hyoid bone movement during swallowing and elucidate the application of real-time US for assessing swallowing dysfunction. We collected data from HNC and thyroid cancer patients with dysphagia symptoms and healthy controls without a history of cancer or dysphagia symptoms for comparison. Real-time submental US was used to check the anterior belly of the digastric muscle, geniohyoid (GH) muscles, and hyoid bone movement during swallowing. Logistic regression analysis was used to explore significant US predictors of dysphagia. Based on the regression coefficients of independent variables, we established the nomogram prediction model for dysphagia. There were significant differences in GH size at contraction, GH size increase percentage, GH length at rest, GH length increase percentage, anterior displacement of the hyoid bone and superior displacement of the hyoid bone between the cancer survivors with dysphagia and volunteers without dysphagia. In multivariate logistic analysis, after adjusting for sex and age, the proportion of GH length contraction <22% (odds ratio [OR]: 6.8 95% confidence interval [CI]: 1.1-42.6) and hyoid bone superior displacement <3.3 mm (OR: 10.7, 1.8-64.1) were associated with a higher risk of dysphagia (P < 0.05). We confirmed that GH muscle and hyoid bone movement are important for normal swallowing function. US is a good method to assess the suprahyoid muscles and hyoid bone movement, which could provide valuable information on swallowing.

Evaluation of Dent aluation of Dentoskeletal and Phar eletal and Pharyngeal Air yngeal Airway Changes after y Changes after Treatment with Twin Block and Monoblock Appliance in Growing Patients

Objective: To compare of pharyngeal airway dimensions and dentoskeletal changes after treatment with twin block (TWB) and monoblock (MB) appliance in growing patients. Methods: The sample was comprised of a total of 72 patients at the ages of 10 to 13. The TWB group consisted of 36 patients (22 females, 14 males, mean age: 11.9±1.5) and MB group consisted of 36 patients (18 females, 18 males, mean age: 11.8±1.2). The linear and angular measurements were evaluated on lateral cephalometric radiographs at beginning (T0) and end of treatment (T1). Results: The amounts of increase in the inferior airway space, L1xNB, IMPA and FMA measurements from T0 to T1 in the TWB group were significantly higher (p &lt; 0.05).In the TWB group, the amounts of the increase in the soft palate thickness, distance between hyoid and C3, Co-A and Co-Gn measurements from T0 to T1 in the female patients were significantly higher (p &lt; 0.05).In the MB group, the amounts of increase in the Upper adenoid thickness and Vertical airway length measurements from T0 to T1 in the female patients were significantly higher (p &lt; 0.05). Conclusion: Both the MB and TWB appliances increase the pharyngeal airway dimensions, and the lower airway is most affected by the appliance type. The effects of the MB and TWB appliances on tongue dimensions and hyoid bone movements are different.

Analysis of swallowing function after anterior/posterior surgery for cervical degenerative disorders and factors related to the occurrence of postoperative dysphagia

BACKGROUND CONTEXTDysphagia is one of the postoperative complications of cervical degenerative disorders. However, few studies have evaluated the pre- and postoperative swallowing function in detail. PURPOSETo analyze pre- and postoperative swallowing dynamics kinetically and investigate factors associated with postoperative dysphagia in patients with cervical degenerative disorders. STUDY DESIGNRetrospective review of prospectively collected data. PATIENT SAMPLEA total of 41 consecutive patients who underwent an anterior approach (anterior cervical discectomy/corpectomy and fusion (ACDF, ACCF), hybrid surgery (ACDF+ACCF) and total disc replacement) and 44 consecutive patients who underwent a posterior approach (laminoplasty and laminoplasty/laminectomy with fusion). OUTCOME MEASURESWe compared the pre- and postoperative functional oral intake scale (FOIS), dysphagia severity scale (DSS), esophageal dysphagia, anterior/superior hyoid movement, upper esophageal sphincter (UES) opening, pharyngeal transit time, bolus residue scale (BRS), and the number of swallows. METHODSVideofluoroscopy was performed on the day before surgery and within two weeks after surgery. Data related to age, gender, disease, surgical procedure, surgical site, operative time, and blood loss were collected from the medical records. Pre- and postoperative data were compared for each item in the anterior and posterior approaches. The odds ratio of dysphagia after an anterior approach was also calculated. RESULTSIn the anterior approach, DSS, FOIS, the anterior and superior hyoid movements, maximum UES opening, BRS, and number of swallows worsened postoperatively (p<.05, respectively). In the posterior approach, DSS, FOIS, the anterior hyoid movement, and BRS worsened postoperatively (p<.05, respectively). The factors associated with dysphagia were a proximal surgical site above C3 (OR: 14.40, CI: 2.84−73.02), blood loss >100 mL (OR: 9.60, CI: 2.06−44.74), an operative time >200 minutes (OR: 8.18, CI: 1.51−44.49), and an extensive surgical field of more than three intervertebral levels (OR: 6.72, CI: 1.50−30.07). The decline in swallowing function after the posterior approach was related to aging (p=.045). CONCLUSIONSEach approach may decrease swallowing function, especially because of the limitation on the anterior hyoid movement. Dysphagia after anterior approaches was associated with the operative site, operative time, and blood loss.

Characteristics of submental muscles function and hyoid bone movement in patients with dysphagia after stroke.

Dysphagia is one of the common complications after stroke. Dysphagia significantly increases the probability of serious adverse consequences. The purpose of this study was to compare the characteristics of submental muscles electromyography and hyoid motion parameters between patients with dysphagia after stroke and healthy controls, and whether there is a synergistic effect between the function of the submental muscles and the movement of the hyoid. Fifteen patients with post-stroke dysphagia and fifteen healthy adults simultaneously underwent the videofluoroscopic and surface electromyography of the submental muscles while swallowing 5ml of concentrated liquid barium sulphate. The electromyographic signal of the submental muscles was analysed along with parameters of hyoid movement. Stage transition duration and duration of surface electromyographic activity were extended significantly in post-stroke dysphagia patients(P<0.05). Surface electromyography amplitude and hyoid movement were significantly reduced in patients (P<0.05). There was a significant correlation between the maximum hyoid movement distance and the peak sEMG amplitude in healthy controls (r=0.660, P=0.014), but not in patients with dysphagia after stroke (r=0.425, P=0.148). Submental muscles electromyographic signal changes in patients may be the result of uncoordinated muscle contractions and decreased muscle strength. Furthermore, the reduced hyoid movement distance may be due to impaired function of the submental muscles. In addition, the submental muscles and hyoid movement or other swallowing structures functions were impaired to varying degrees, resulting in the disappearance of the correlation between the maximum movement distance of the hyoid and the peak amplitude.