Hyoid displacement in post-treatment cancer patients: preliminary findings

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.

Quantifying Oropharyngeal Swallowing Impairment in Response to Bolus Viscosity

PURPOSE

The purpose of this study was to test the feasibility for quantifying changes in oropharyngeal swallowing impairment in response to alteration in bolus viscosity using a reliable and valid method of observational measurement-the Modified Barium Swallow Impairment Profile (MBSImP).

METHOD

This retrospective analysis included a heterogeneous cohort of 119 patients with suspected dysphagia that underwent a videofluoroscopic swallowing study as part of clinical care. Using consensus scoring, two expert clinicians assigned MBSImP scores to components related to oropharyngeal swallowing function between two bolus viscosities (thin liquid and pudding): epiglottic movement, laryngeal elevation, anterior hyoid excursion, tongue base retraction, pharyngeal stripping wave, and pharyngoesophageal segment opening (PESO). Comparisons between the two bolus viscosities were investigated for each component.

RESULTS

Higher (worse) scores were observed in the thin-liquid trial compared with the pudding trial for the following MBSImP components: anterior hyoid excursion (p = .03), epiglottic movement (p < .001), pharyngeal stripping wave (p < .001), and PESO (p = .002). Lower (better) scores were observed in the liquid trial compared with the pudding trial for one component-tongue base retraction (Component 15) only (p < .001).

CONCLUSION

These findings provide further evidence for positive influences of viscosity on the swallow mechanism, including influences of sensory feedback on the sensorimotor swallow program.

Functional outcomes of hyoid suspension in anterior oromandibular reconstruction

BACKGROUND

Hyoid suspension can be considered in major oromandibular reconstruction. The impact of hyoid suspension on flap viability, swallowing outcomes, airway, and long term radiographic hyoid position is unknown. The objective of this study is to describe outcomes after hyoid suspension in anterior mandibular reconstruction with fibular free flaps. We hypothesized hyoid suspension would not affect flap viability and would benefit functional outcomes.

METHODS

A retrospective cohort study was conducted in an academic tertiary medical center. The study consisted of 84 adults who underwent anterior mandibular reconstruction from February 2014 to September 2020. The primary outcome studied was the post-suspension flap viability. Secondary outcomes include pre/post-operative hyomental distance on computed-tomography, duration of perioperative tracheostomy, postoperative feeding tube dependence, and post-operative aspiration pneumonia.

RESULTS

A total of 84, predominantly male (66.5 %), patients with an average age of 58.9 ± 11.5 were included in the study. Of those that met inclusion criteria, 25 (29.4 %) underwent intraoperative hyoid suspension. Univariable analysis showed no significant association between resuspension and post-operative total flap loss (p = 0.864) or partial flap loss (p = 0.318). There was no association between hyoid suspension and any of the studied postoperative functional outcomes or radiographic measures.

CONCLUSIONS

Hyoid suspension is an option during oromandibular reconstruction and does not impact flap viability. The impact on functional outcomes and long-term hyoid position in this patient subset remains unclear.

Examination of Suprahyoid Muscle Resection and Other Factors Affecting Swallowing Function in Patients With Advanced Oral Cancer After Surgical Resection and Reconstruction

Dysphagia is one of the most common adverse effects associated with oral cancer therapy and could greatly impair postoperative quality of life. The objective of this study was to analyze postoperative swallowing outcomes and factors influencing postoperative swallowing function in patients with advanced oral cancer who underwent primary reconstruction after surgical resection to identify patients at risk of experiencing severe dysphagia after immediate reconstruction of surgical defects, and to determine an ideal approach to provide appropriate perioperative interventions. The swallowing status was evaluated at 4 week postoperatively using the Functional Oral Intake Scale. We also analyzed the effects of patient, tumor, surgical, and other factors on postoperative swallowing function. The study included 67 patients. At 4 weeks postoperatively, 11 patients showed reduced swallowing function, whereas 56 patients showed good swallowing function. The number of resected suprahyoid muscles (odds ratio, 1.55; 95% confidence interval, 1.03-2.32; P=0.035) was an independent factor influencing postoperative swallowing function. Thus, among patients who underwent radical resection of oral cancer with primary reconstruction, those with extensive resection of the suprahyoid muscles were at higher risk of developing postoperative dysphagia. These findings are expected to facilitate increased vigilance for dysphagia, better counseling, and appropriate rehabilitation interventions.

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

PURPOSE

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

METHOD

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

RESULT

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

CONCLUSION

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

Increased viscosity of milk during infant feeding improves swallow safety through modifying sucking in an animal model

Infants experiencing frequent aspiration, the entry of milk into the airway, are often prescribed thickened fluids to improve swallow safety. However, research on the outcomes of thickened milk on infant feeding have been limited to documenting rates of aspiration and the rheologic properties of milk following thickening. As a result, we have little insight into the physiologic and behavioral mechanisms driving differences in performance during feeding on high viscosity milk. Understanding the physiologic and behavioral mechanisms driving variation in performance at different viscosities is especially critical, because the structures involved in feeding respond differently to sensory stimulation. We used infant pigs, a validated animal model for infant feeding, to test how the tongue, soft palate, and hyoid respond to changes in viscosity during sucking and swallowing, in addition to measuring swallow safety and bolus size. We found that the tongue exhibited substantive changes in its movements associated with thickened fluids during sucking and swallowing, but that pharyngeal transit time as well as hyoid and soft palate movements during swallowing were unaffected. This work demonstrates the integrated nature of infant feeding and that behaviors associated with sucking are more sensitive to sensorimotor feedback associated with changes in milk viscosity than those associated with the pharyngeal swallow, likely due to its reflexive nature.

Impact of Thickened Liquids on Laryngeal Movement Velocity in Patients with Dysphagia

Considering that thickened liquids are frequently used for patients with dysphagia, elucidating their impact on laryngeal dynamics is important. Although studies have investigated the impact of thickened liquids on laryngeal movement velocity among healthy young adults, no study has examined the same among patients with dysphagia. We aimed to elucidate the influence of bolus consistency on laryngeal movement velocity and surface electromyographic activity of the suprahyoid muscles in patients with dysphagia. Participants included 18 male, poststroke patients with dysphagia, whereas patients with true bulbar paralysis, head and neck cancer, neuromuscular disease, or recurrent nerve paralysis were excluded. A video fluoroscopic swallowing study (VFSS) was performed while swallowing 3 mL of moderately thick and thin liquids. Quantitative VFSS analysis, including factors such as laryngeal peak velocity, laryngeal mean velocity, laryngeal movement distance, duration of the laryngeal elevation movement, and the temporal location of laryngeal vestibule closure within the laryngeal elevation movement was performed. Muscle activity was evaluated using integrated muscles activity values obtained from electromyography (iEMG) of the suprahyoid muscle during swallowing. VFSS analysis showed that laryngeal peak velocity and laryngeal mean velocity were significantly faster while swallowing moderately thick than while swallowing thin liquids. Laryngeal movement distance was significantly greater while swallowing moderately thick than while swallowing thin liquids. iEMG was significantly higher while swallowing moderately thick liquids than while swallowing thin liquids. Compared to thin liquids, moderately thick induced an increase in laryngeal movement velocity and in suprahyoid muscle activity among patients with dysphagia, a finding consistent with that of a previous study among healthy adults.

Sonographic assessment of swallowing in irradiated nasopharyngeal carcinoma patients

Objectives/Hypothesis

Ultrasonography is an emerging clinical tool to study the dysfunction of swallowing muscles. This was the first sonographic study to assess the relationship between suprahyoid muscle contraction, hyoid bone displacement, and penetration‐aspiration status (PAS) during swallowing in nasopharyngeal carcinoma (NPC) patients treated with radiotherapy (RT). The study also aimed to establish reliability data for the sonographic technique described.

Study Design

Cross‐sectional study.

Methods

Geniohyoid muscle contraction was quantified using brightness‐mode ultrasonography in this study of 40 post‐RT NPC patients. A series of physiological parameters and PAS were measured using videofluoroscopy.

Results

Intra‐ and inter‐rater agreement values ranged from 0.75 to 0.96 across various sonographic measurements. Percentage increase in the cross‐sectional area of the geniohyoid muscle correlated with anterior (r = 0.42, P < .05) but not superior (r = 0.27, P = .09) hyoid displacement. Anterior hyoid displacement and pharyngeal constriction ratio were significantly associated with PAS score.

Conclusions

Sonographic measurement of suprahyoid muscles provides valuable information on muscle function and is potentially a useful clinical tool in swallowing assessment. Further research is needed to refine the role of this examination in dysphagia.

Level of Evidence

2b. Laryngoscope, 2552–2559, 2018

Hyoid bone displacement as parameter for swallowing impairment in patients treated for advanced head and neck cancer

Reduced hyoid displacement is thought to contribute to aspiration and pharyngeal residues in head and neck cancer (HNC) patients with dysphagia. To further study hyoid elevation and anterior excursion in HNC patients, this study reports on temporal/kinematic measures of hyoid displacement, with the additional goal to investigate correlations with clinical swallowing impairment. A single-blind analysis of data collected as part of a larger prospective study was performed at three time points before and after chemoradiotherapy. Twenty-five patients had undergone clinical swallowing assessments at baseline, 10-weeks, and 1-year post-treatment. Analysis of videofluoroscopic studies was done on different swallowing consistencies of varying amounts. The studies were independently reviewed frame-by-frame by two clinicians to assess temporal (onset and duration) and kinematic (anterior/superior movement) measures of hyoid displacement (ImageJ), laryngeal penetration/aspiration, and presence of vallecula/pyriform sinus residues. Patient-reported oral intake and swallowing function were also evaluated. Mean maximum hyoid displacement ranged from 9.4 mm (23 % of C2-4 distance) to 12.6 mm (27 %) anteriorly, and from 18.9 mm (41 %) to 24.9 mm (54 %) superiorly, depending on bolus volume and consistency. Patients with reduced superior hyoid displacement perceived significantly more swallowing impairment. No correlation between delayed or reduced hyoid excursion and aspiration or residue scores could be demonstrated. Hyoid displacement is subject to variability from a number of sources. Based on the results, this parameter seems not very valuable for clinical use in HNC patients with dysphagia.

Effect of Bolus Viscosity on the Safety and Efficacy of Swallowing and the Kinematics of the Swallow Response in Patients with Oropharyngeal Dysphagia: White Paper by the European Society for Swallowing Disorders (ESSD)

BACKGROUND

Fluid thickening is a well-established management strategy for oropharyngeal dysphagia (OD). However, the effects of thickening agents on the physiology of impaired swallow responses are not fully understood, and there is no agreement on the degree of bolus thickening.

AIM

To review the literature and to produce a white paper of the European Society for Swallowing Disorders (ESSD) describing the evidence in the literature on the effect that bolus modification has upon the physiology, efficacy and safety of swallowing in adults with OD.

METHODS

A systematic search was performed using the electronic Pubmed and Embase databases. Articles in English available up to July 2015 were considered. The inclusion criteria swallowing studies on adults over 18 years of age; healthy people or patients with oropharyngeal dysphagia; bolus modification; effects of bolus modification on swallow safety (penetration/aspiration) and efficacy; and/or physiology and original articles written in English. The exclusion criteria consisted of oesophageal dysphagia and conference abstracts or presentations. The quality of the selected papers and the level of research evidence were assessed by standard quality assessments.

RESULTS

At the end of the selection process, 33 articles were considered. The quality of all included studies was assessed using systematic, reproducible, and quantitative tools (Kmet and NHMRC) concluding that all the selected articles reached a valid level of evidence. The literature search gathered data from various sources, ranging from double-blind randomised control trials to systematic reviews focused on changes occurring in swallowing physiology caused by thickened fluids. Main results suggest that increasing bolus viscosity (a) results in increased safety of swallowing, (b) also results in increased amounts of oral and/or pharyngeal residue which may result in post-swallow airway invasion, (c) impacts the physiology with increased lingual pressure patterns, no major changes in impaired airway protection mechanisms, and controversial effects on oral and pharyngeal transit time, hyoid displacements, onset of UOS opening and bolus velocity-with several articles suggesting the therapeutic effect of thickeners is also due to intrinsic bolus properties, (d) reduces palatability of thickened fluids and (e) correlates with increased risk of dehydration and decreased quality of life although the severity of dysphagia may be an confounding factor.

CONCLUSIONS

The ESSD concludes that there is evidence for increasing viscosity to reduce the risk of airway invasion and that it is a valid management strategy for OD. However, new thickening agents should be developed to avoid the negative effects of increasing viscosity on residue, palatability, and treatment compliance. New randomised controlled trials should establish the optimal viscosity level for each phenotype of dysphagic patients and descriptors, terminology and viscosity measurements must be standardised. This white paper is the first step towards the development of a clinical guideline on bolus modification for patients with oropharyngeal dysphagia.

Electromyography of Swallowing with Fine Wire Intramuscular Electrodes in Healthy Human: Amplitude Difference of Selected Hyoid Muscles

Few studies have examined the intensity of muscle activity during swallowing in healthy humans. We examined selected hyoid muscles using fine wire intramuscular electromyography (EMG) during swallowing of four food consistencies. Thirteen healthy adults were studied using videofluorography and EMG of the anterior belly of digastric (ABD), geniohyoid (GH), sternohyoid (SH), and masseter (MA; surface electrodes) while ingesting thin liquid (three trials) and solid food of three consistencies (banana, tofu, and cookie, three trials each). After rectification, integration, and normalization, peak EMG amplitudes for each muscle in each trial were measured. Hyoid displacements were measured in two dimensions. Data were analyzed using repeated measures ANOVA with Bonferroni correction. GH had the highest adjusted amplitude for both solids and liquid. For MA and ABD, amplitude was highest with triturated cookie. For ABD, amplitude was lowest with liquid. There were no significant food consistency effects for GH or SH. Hyoid displacements were greatest for cookie and the lowest for liquid. EMG amplitude varied with initial food consistency. The high peak EMG amplitude of GH is consistent with its essential role in opening the upper esophageal sphincter. High MA amplitude with hard solid foods is likely due to the higher tongue-palate pressure with triturated solids. The higher ABD amplitude with solid food is associated with greater hyoid displacement. These findings support the existence of a central pattern generator that modifies the level of muscle activity during pharyngeal swallowing in response to input from mechanoreceptors in the oral cavity.

Hyoid and laryngeal excursion kinematics - magnitude, duration and velocity - changes following successful exercise-based dysphagia rehabilitation: MDTP

Variability in magnitude of deglutitional hyolaryngeal excursion in patients with dysphagia suggests that it does not adequately represent the kinematics of swallowing difficulties or recovery following rehabilitation. On the other hand, reduced hyolaryngeal excursion velocity has been reported in patients with dysphagia. While increased movement velocity often accompanies clinical and functional recovery in many diseases, velocity changes in swallowing-related movement following dysphagia therapy have not been well studied. This study evaluated changes in hyoid and laryngeal excursion (magnitude, duration and velocity) before and following successful dysphagia therapy to provide a more comprehensive representation of improvement to swallowing kinematics in patients who have experienced successful rehabilitation. A secondary analysis of case series data was completed. Eight patients with severe, chronic dysphagia completed a standard course of an exercise-based dysphagia treatment programme (McNeill dysphagia therapy program, MDTP). Pre- and post-treatment, kinematic aspects of swallowing were evaluated for thin liquid, thick liquid and pudding swallows. Maximum hyoid and laryngeal excursion magnitude and excursion duration were measured. Excursion velocities were calculated from excursion magnitude and duration measures. Successful treatment for dysphagia facilitated increased hyolaryngeal excursion magnitude, duration and velocity. These changes were most prominent for the hyoid and most often observed with thin liquids. By examining hyoid and laryngeal excursion velocity in patients who have experienced successful dysphagia rehabilitation, this study demonstrated the value of evaluating spatial and temporal aspects of swallowing kinematics in a single measure for a more comprehensive representation of positive changes underlying functional recovery.

Use of an anatomical scalar to control for sex-based size differences in measures of hyoid excursion during swallowing

PURPOSE

Traditional methods for measuring hyoid excursion from dynamic videofluoroscopy recordings involve calculating changes in position in absolute units (mm). This method shows a high degree of variability across studies but agreement that greater hyoid excursion occurs in men than in women. Given that men are typically taller than women, the authors hypothesized that controlling for participant size might neutralize apparent sex-based differences in hyoid excursion.

METHOD

Hyoid excursion in 20 young (<45) healthy volunteers (10 male), stratified by height, was measured in a tightly controlled videofluoroscopic protocol.

RESULTS

The study identified an anatomical scalar (C2-C4 length), visible on the videofluoroscopic image, correlated with participant height. This scalar differed significantly between men and women. By incorporating the anatomical scalar as a continuous covariate in repeated measures mixed-model analyses of variance of hyoid excursion, apparent sex-based differences were neutralized. Transforming measures of hyoid excursion into anatomically scaled units achieved the same result, reducing variation attributable to sex-based differences in participant size.

CONCLUSIONS

Hyoid excursion during swallowing is dependent on a person's size. If measurements do not control for this source of variation, apparent sex differences in hyoid excursion are seen.