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How the body interacts with the brain to perform vital life functions, such as feeding, is a fundamental issue in physiology and neuroscience. Here, we use a whole-animal scanning transmission electron microscopy volume of Drosophila to map the neuronal circuits that connect the entire enteric nervous system to the brain via the insect vagus nerve at synaptic resolution. We identify a gut-brain feedback loop in which Piezo-expressing mechanosensory neurons in the esophagus convey food passage information to a cluster of six serotonergic neurons in the brain. Together with information on food value, these central serotonergic neurons enhance the activity of serotonin receptor 7-expressing motor neurons that drive swallowing. This elemental circuit architecture includes an axo-axonic synaptic connection from the glutamatergic motor neurons innervating the esophageal muscles onto the mechanosensory neurons that signal to the serotonergic neurons. Our analysis elucidates a neuromodulatory sensory-motor system in which ongoing motor activity is strengthened through serotonin upon completion of a biologically meaningful action, and it may represent an ancient form of motor learning. [Display omitted] • STEM reconstruction of the entire enteric nervous system at the synaptic level • Piezo-mechanoreceptive neurons convey completed swallowing action to the brain • Central serotonergic neurons evaluate the biological valence of swallowed food • Serotonin modulates swallowing through motor neurons driving esophageal peristalsis Using a whole-animal serial transmission electron microscopy dataset, Schoofs et al. provide a complete reconstruction of a sensorimotor circuit underlying the Drosophila swallowing system. Through the vagus nerve, serotonergic neurons rate food based on mechanosensory and chemosensory information and modulate esophageal peristalsis. [ABSTRACT FROM AUTHOR]

Background and Aim: This study aims to assess the impact of supraglottic cancer on swallowing functionality and its anatomical correlations before and after laser surgery. The study seeks to determine the extent of score changes post-surgery, pinpoint the most influential anatomical component in swallowing, predict post-surgery outcomes, and ascertain the effect on patients' quality of life. Methods: Patients with supraglottic cancer and dysphagia were identified through stroboscopy and indirect laryngoscopy. Exclusion criteria encompassed a history of prior radiotherapy, chemotherapy, or distant metastases. Demographic data, tumor stage, comorbidities, risk factors, and treatment details were documented. Swallowing evaluation employed the translated EAT10 self-assessment questionnaire, administered before and after transoral laser microsurgery (TLM) at baseline and 6 months later. Additional treatments, rehabilitation duration, NG tube use, and post-surgery complications were recorded. Results: At the six-month follow-up, 9 patients had EAT-10 scores ≥ 3, while 7 patients scored < 3. Five patients underwent post-TLM additional therapies, and 9 patients had neck dissections. Involved subunits were epiglottis (11 patients), arytenoid (5 patients), FVC (13 patients), and TVC (3 patients). Seven patients received dysphagia treatment. Analysis revealed significant associations between follow-up EAT-10 scores and dysphagia treatment (p = 0.04), smoking (p = 0.02), and FVC involvement (p = 0.02). Conclusion: Our study on supraglottic cancer treatment with transoral laser microsurgery (TLM) revealed variable EAT-10 scores after a six-month follow-up. Adjunctive therapies and neck dissections were administered to some patients. Significant associations were found between follow-up scores, dysphagia treatment, smoking history, and FVC involvement, highlighting the complex interplay between interventions and patient factors. Further research is needed for optimization. [ABSTRACT FROM AUTHOR]

Introduction The Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scale was developed to evaluate the safety, efficiency, and overall pharyngeal swallowing performance in patients with dysphagia (DIGESTs, DIGESTe, and DIGESTt, respectively). Although various types of swallowing dysfunction are encountered in children with esophageal atresia (EA), oropharyngeal dysphagia poses risk for aspiration. Therefore, a retrospective study was performed to evaluate the safety and efficacy of swallowing by using DIGEST score in children with EA. Patients and Methods Thirty-nine EA patients were included. The demographic features, respiratory problems, results, and outcomes of surgical treatment were evaluated from medical records. The videofluoroscopic swallowing evaluation investigated for both airway protection and bolus residuals at the level of vallecula, posterior pharyngeal wall, and pyriform sinus at liquid and pudding consistencies. The penetration and aspiration scale (PAS) was used to define penetration and aspiration severity, and DIGEST was used to evaluate DIGESTs, DIGESTe, and DIGESTt. Results The median age of the patients were 13 months (7–39 months), and male-to-female ratio was 25:14. Sixty-seven percent of patients were type-C EA and 61% of them has associated anomalies; 38% of patients had aspiration (PAS = 6–8) in liquids and 10% in pudding consistency. Life-threatening/profound swallowing dysfunction in DIGESTe (DIGEST = 4) was seen in 13% (n = 5) of patients; 40% of EA patients showed severe problems in DIGESTt. Conclusion DIGEST is a valid and reliable tool to define the efficacy and safety of swallowing in children with EA. [ABSTRACT FROM AUTHOR]

Swallowing is an essential process to maintain homeostasis in the human body. With aging, changes occur in both central and peripheral structures, giving rise to presbyphagia, involving morphological and functional alterations in swallowing. However, there is a lack of consensus on the definition of presbyphagia and its relationship with dysphagia. The primary objective of this research is to analyze the proposed definitions for the term "presbyphagia" in specialized literature and, secondarily, to assess how these definitions can influence the diagnosis of oropharyngeal dysphagia (OD). A systematic review was conducted to analyze the proposed definitions of presbyphagia and their impact on dysphagia diagnosis. Three main approaches to the definitions of presbyphagia were identified: (1) presbyphagia as an alteration in the swallowing process in healthy older adults, (2) presbyphagia as a swallowing disorder compensated by the physiological potential of healthy older adults, and (3) presbyphagia as a synonym for dysphagia. This study addresses the need for a clear definition of presbyphagia in older adults. It is concluded that presbyphagia should be understood as the etiology of OD rather than a compensated disorder or a synonym. This has significant implications for the diagnosis and treatment of swallowing disorders in the aging population. Given the ongoing nature of scientific discussion in this field, further research is required. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) is a common treatment for motor symptoms of Parkinson disease (PD), a condition associated with increased risk of dysphagia. The effect of DBS on swallowing function has not been comprehensively evaluated using gold-standard imaging techniques, particularly for globus pallidus internus (GPi) DBS. The objective of this retrospective, cross-sectional study was to identify differences in swallowing safety and timing kinematics among PD subjects with and without GPi DBS. We investigated the effects of unilateral and bilateral GPi DBS as well as the relationship between swallowing safety and DBS stimulation parameters, using retrospective analysis of videofluoroscopy recordings (71 recordings from 36 subjects) from electronic medical records. Outcomes were analyzed by surgical status (pre-surgical, unilateral DBS, bilateral DBS). The primary outcome was percent of thin-liquid bolus trials rated as unsafe, with Penetration-Aspiration Scale scores of 3 or higher. Secondary analyses included swallowing timing measures, relationships between swallowing safety and DBS stimulation parameters, and Dynamic Imaging Grade of Swallowing Toxicity ratings. Most subjects swallowed all boluses safely (19/29 in the pre-surgical, 16/26 in the unilateral DBS, and 10/16 in the bilateral DBS conditions). Swallowing safety impairment did not differ among stimulation groups. There was no main effect of stimulation condition on timing metrics, though main effects were found for sex and bolus type. Stimulation parameters were not correlated with swallowing safety. Swallowing efficiency and overall impairment did not differ among conditions. These results provide evidence that GPi DBS does not affect pharyngeal swallowing function. Further, prospective, investigations are needed. [ABSTRACT FROM AUTHOR]

This study evaluated the validity of pharyngeal 2D area measurements acquired from the lateral view for predicting the actual 3D volume in healthy adults during swallowing. Seventy-five healthy adults (39 females, 36 males; mean age 51.3 years) were examined using 320-row area detector computed tomography (320-ADCT). All participants swallowed a 10 mL honey-thick barium bolus upon command while seated in a 45° semi-reclining position. Multi-planar reconstruction images and dynamic 3D-CT images were obtained using Aquilion ONE software. Pharyngeal 2D area and 3D volume measurements were taken before swallowing and at the frame depicting maximum pharyngeal constriction. Pharyngeal volume before swallowing (PVhold) was accurately predicted by 2D area (R2 = 0.816). Adding height and sex to the model increased R2 to 0.836. Regarding pharyngeal volume during maximum constriction (PVmax), 2D area also exhibited acceptable predictive power (R2 = 0.777). However, analysis of statistical residuals and outliers revealed a greater tendency for prediction errors when there is less complete constriction of the pharynx as well as asymmetry in bolus flow or movement. Findings highlight the importance of routinely incorporating anterior–posterior views during VFSS exams. Future work is needed to determine clinical utility of pharyngeal volume measurements derived from 320-ADCT. [ABSTRACT FROM AUTHOR]

Dysphagia screening tests are useful in identifying possible dysphagia for further evaluation and in supporting feeding recommendations. This study aimed to investigate swallowing parameters in children, while widening the pool of data available, using the '100 ml-Timed Water Swallow Test' (100 ml-TWST). Sixty Singaporean children aged 4 to 18 years old completed the 100 ml-TWST via a cup and a straw. Task completion, presence of cough, choke or throat clear, post-swallow voice quality, total time taken and number of swallows were observed. Subsequently, analysis of time per swallow (T/S), volume per swallow (V/S) and volume per time or swallowing capacity (V/T) were performed. Higher tendencies for coughing and task incompletion were observed in younger participants. A shorter time taken, fewer number of swallows, greater V/S and greater swallowing capacity were observed for adolescent or male participants, or via the mode of cup drinking. These could be due to oropharyngeal structural changes and swallow maturation with age, an increased capacity of oropharyngeal structures for swallowing in adolescent males, and more controlled or paced drinking from a straw. A plateau in time taken, number of swallows and swallowing capacity in adolescence were also observed, possibly indicating an emerging maturation of swallow functions during that period. Interestingly, speed of bolus movement was largely unaffected by age, gender and mode of drinking. Pilot data for children with no dysphagia have been established, while gaining insight into the swallowing parameters and maturation process in the paediatric population. [ABSTRACT FROM AUTHOR]

Purpose: Age-related changes to the swallowing mechanism, or presbyphagia, may put older adults at a higher risk for developing diseases and dysphagia. Maintaining swallowing functions could help prevent frailty and facilitate healthy ageing. This review summarises and appraises the effects of oropharyngeal exercises on the swallowing functions of healthy older adults without dysphagia. It is hypothesised that these exercises will strengthen and improve the structures and functions of the normal ageing swallow. Method: This review was reported according to the PRISMA 2020 guidelines. Five electronic databases (Medline, Embase, Cochrane Library, Web of Science, CINAHL) and Google Scholar were searched in June 2021. A rerun was done in January 2023. Study selection, data extraction, and quality assessment were done by two independent raters. Result: A total of 23 studies were reviewed. Meta-analysis was not conducted due to the heterogenous training protocols and outcomes. Majority (n = 21) had fair quality due to incomplete reporting. Exercises targeting oral structures were implemented the most (n = 15), followed by variations of the head lift (n = 4), and effortful swallow exercise (n = 1). Others implemented combined or multiapproach exercise studies (n = 3). Apart from surface electromyography findings, statistically significant improvements in oral and pharyngeal phase swallowing outcomes such as increased lingual isometric and swallowing pressures, bite force, muscle thickness, hyolaryngeal excursion, and upper oesophageal sphincter opening diameter were reported in 95% of the studies (n = 22). Conclusion: Collective evidence suggests that strength training for swallowing-related structures leads to increases in structural strength, endurance, and muscle mass. The effects of exercises on overall swallowing efficiency and safety remain unclear. Results should be interpreted with caution due to methodological limitations. Further research should examine the long-term effects of these exercises in preventing frailty and reducing the burden of dysphagia in older adults. [ABSTRACT FROM AUTHOR]

Background Methods Key Results Conclusion and Inferences Oropharyngeal dysphagia (OD) commonly occurs in neuromuscular diseases (NMD). Appropriate management involves early detection, clinical evaluation, and tailored follow‐up to minimize complications. Various assessment tools exist, including the Sydney Swallow Questionnaire (SSQ), a patient‐reported outcome measure for assessing OD severity in adult patients. This paper proposes utilizing an innovative risk matrix (OD‐Risk‐Matrix) to enhance SSQ interpretation. This matrix categorizes OD risk for each SSQ question, offering valuable assistance to clinicians.This study analyzes SSQ results from a cohort of individuals with NMD (n = 57). Patients filled in the SSQ during outpatient visits at our neuromuscular center. Subsequently, SSQ scores were grouped by NMD conditions and interpreted using the OD‐Risk‐Matrix categorizing each question's risk as low, moderate, or high. This matrix is based on the SSQ results by categorizing the risk of OD for each question, as well as the likelihood of occurrence of OD.In light of the OD‐Risk‐Matrix, the interpretation of SSQ scores revealed various risk categories associated with each question, while also highlighting distinct OD characteristics and discrepancies among the different NMDs.In conclusion, the OD‐Risk‐Matrix offers a framework for interpreting the SSQ, revealing variations in the risks of OD among different questions in patients with NMD. This novel approach could be a valuable tool in SSQ interpretation to identify specific fields of OD and could lead to a tailored management plan, prioritizing interventions aimed at reducing the risk of aspiration, ensuring proper nutrition, and enhancing swallowing safety and efficiency. [ABSTRACT FROM AUTHOR]

Respiratory–swallowing coordination (RSC) is well established as an essential airway‐protective mechanism. Previous studies have used nasal airflow and/or kinematic rib cage and abdominal measures to assess respiration surrounding swallowing, meaning that the direct influence of oral respiration on RSC remains unknown. This study used a partitioned oronasal facemask to compare respiratory phase patterns measured using isolated nasal airflow with those measured using combined oronasal airflow during non‐ingestive and ingestive swallowing tasks. Twenty‐four healthy individuals with no respiratory or swallowing disorders were assessed at rest and during cued dry, 10 mL water, continuous drinking and cracker swallowing tasks. Respiratory phase patterns were determined for discrete swallows using the nasal and combined oronasal channels separately. There was variable agreement between respiratory phase patterns according to the nasal and oronasal channels across swallowing conditions. The frequency of exhale–swallow–exhale, inhale–swallow–exhale and exhale–swallow–inhale patterns increased by 2%–3% each with the addition of oral flow data to nasal data, whereas the prevalence of inhale–swallow–inhale and ambiguous patterns decreased. This suggests that estimates of respiratory phase patterns are altered minimally by inclusion of oral respiratory estimates in a healthy sample. There were several additional findings of note, including lower within‐participant, within‐session trial consistency (test–retest reliability) than expected, suggesting high variability in respiratory phase patterns across trials. Additionally, data showed evidence of swallowing non‐respiratory flow at the beginning and end of the respiratory–swallowing pause, moving in both inward and outward directions, potentially expanding current understanding of swallowing non‐respiratory flow. Further in‐depth physiological investigations are required to improve understanding of these findings. [ABSTRACT FROM AUTHOR]

Background Objective(s) Methods Results Conclusion Swallowing is a complex function that requires precise coordination between different muscles. Weakness in submental muscles can lead to complications such as pharyngeal residue and aspiration. Therefore, exercise interventions targeting these muscles, such as the Head‐Lift Exercise (HLE), are clinically important but pose challenges.This study aimed to compare the myoelectric activity of submental muscles during traditional Head‐Lift Exercise (HLE), Tongue‐Press Exercise (TPE) and Head Extension Tongue‐Press Exercise (HETPE), providing potential alternatives to HLE.Thirty healthy volunteers (22 females and 8 males, mean age 25.63 ± 5.27 years) participated in this cross‐sectional study. Surface electromyography (sEMG) recorded activity of the submental muscles bilaterally during HLE, TPE and HETPE. Participants performed each manoeuvre for 14 s, repeated three times in a counterbalanced order. Statistical analyses assessed differences in mean, maximum and median frequency of the sEMG signals among manoeuvres using repeated‐measures analysis of variance (RM‐ANOVA). The experienced irritation levels by participants during manoeuvres were also compared by the Friedman test.HETPE exhibited significantly higher maximum sEMG activity compared to HLE and TPE (p < .05). Mean sEMG activity was significantly increased during HETPE compared to TPE. Median frequency was significantly lower during HETPE compared to the two other exercises, indicating greater muscle fatigue. Participants reported similar levels of irritation for HLE and HETPE, and significantly lower levels during TPE.These results indicate that HETPE is effective in activating and strengthening submental muscles, potentially serving as a viable alternative to HLE without added difficulty. Further research is recommended to assess the long‐term impacts on swallowing physiology in patients with dysphagia. [ABSTRACT FROM AUTHOR]

Background: Swallowing is a complex process that alters with age and neurological diseases; swallowing disorders can be a consequence of both of them. As an advanced multivariate statistical method, hierarchical cluster analysis (HCA) was utilized to make the dendrograms, which was used to find the relationship between the variables. The purpose of this study is to ascertain the type of clustering exhibited by the variables using HCA and to evaluate the approach to major neurodegenerative diseases (MND) with swallowing disorders based on the results obtained. Methods: Data were collected from a total of 173 patients from various neurological diagnoses, such as dementia, Parkinson's disease, stroke and polyneuropathy, aging between 42 and 104 (mean of age 72.85) by using the Montreal Cognitive Assessment, the Edinburgh Feeding Evaluation Scale (EdFED), the Eating Assessment Tool (EAT‐10), and the Modified Mann Swallowing Ability test. From the collected data, dendrograms were formed by using HCA with Ward linkage method. Results: Based on cluster analysis results, clusters demonstrate statistical significance. They center around EdFED, EAT‐10, and age in each MND. In healthy individuals, variables are not clustered as in the patient group. This study holds importance as it can give clinicians a different perspective on determining and managing the elderly population's swallowing problems. Conclusions: The HCA method explicitly proposes which variables should be examined concurrently in the clinic for MND. This research is one of the pioneering studies conducted by using the HCA method. [ABSTRACT FROM AUTHOR]

Purpose: Cricopharyngeus muscle dysfunction (CPMD) is a common clinical occurrence with very few clear diagnostic criteria and multiple pathways for treatment. Incidence of CPMD is not known, but some data suggest around 25% of people with dysphagia experience some degree of CPMD, which negatively impacts swallowing safety and efficiency. Workup and treatment of CPMD can require multidisciplinary collaboration across laryngologists, speech-language pathologists with training in dysphagia management, and gastroenterologists. The purpose of this paper is to review what is known about CPMD and identify areas of future research in CPMD diagnosis and treatment. Methods: An overview of CPMD, relative treatments and disorders, and a discussion of future areas of research needed to improve clinical care of CPMD. Results: Details regarding historical background, pathophysiology and treatment practiced for CPMD are included. Conclusion: In summary, CPMD is a poorly defined disease due to a lack of understanding of its pathophysiology and the lack of consensus diagnostic criteria. Well-designed, prospective clinical trials are necessary to develop a better understanding of clinical incidence of CPMD, impact of the disorder on oropharyngeal swallowing, and how to approach treatment of the disorder surgically or in conjunction with therapy directed by a specialized speech-language pathologist. [ABSTRACT FROM AUTHOR]

Background and purpose: Dysphagia is an important feature of neurodegenerative diseases and potentially life‐threatening in primary progressive aphasia (PPA) but remains poorly characterized in these syndromes. We hypothesized that dysphagia would be more prevalent in nonfluent/agrammatic variant (nfv)PPA than other PPA syndromes, predicted by accompanying motor features, and associated with atrophy affecting regions implicated in swallowing control. Methods: In a retrospective case–control study at our tertiary referral centre, we recruited 56 patients with PPA (21 nfvPPA, 22 semantic variant [sv]PPA, 13 logopenic variant [lv]PPA). Using a pro forma based on caregiver surveys and clinical records, we documented dysphagia (present/absent) and associated, potentially predictive clinical, cognitive, and behavioural features. These were used to train a machine learning model. Patients' brain magnetic resonance imaging scans were assessed using voxel‐based morphometry and region‐of‐interest analyses comparing differential atrophy profiles associated with dysphagia presence/absence. Results: Dysphagia was significantly more prevalent in nfvPPA (43% vs. 5% svPPA and no lvPPA). The machine learning model revealed a hierarchy of features predicting dysphagia in the nfvPPA group, with excellent classification accuracy (90.5%, 95% confidence interval = 77.9–100); the strongest predictor was orofacial apraxia, followed by older age, parkinsonism, more severe behavioural disturbance, and more severe cognitive impairment. Significant grey matter atrophy correlates of dysphagia in nfvPPA were identified in left middle frontal, right superior frontal, and right supramarginal gyri and right caudate. Conclusions: Dysphagia is a common feature of nfvPPA, linked to underlying corticosubcortical network dysfunction. Clinicians should anticipate this symptom particularly in the context of other motor features and more severe disease. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to assess the different pathways between predictor factors such as zygosity, atypical swallowing, mouth breathing, breastfeeding and bottle feeding related to anterior open bite (AOB) in twins. Methods: The study was conducted in monozygotic (MZ) and dizygotic (DZ) twin children aged 3–15 years. AOB, atypical swallowing, mouth breathing, feeding type, duration of bottle use, and mouth opening status during sleep were recorded during oral examination. Partial least squares structural equation model (PLS-SEM) and sobel tests were performed to assess the total and indirect effects among the variables on AOB. Results: A total of 404 children (29.2% MZ;70.8% DZ) participated in this study. The effect of zygosity on mouth breathing in the PLS-SEM model was statistically significant. Conversely, it was determined that mouth breathing effected that atypical swallowing (p = 0.001). Atypical swallowing triggered AOB (p = 0.001). The atypical swallowing has a mediation effect between AOB and mouth breathing (p = 0.020). Mouth breathing causes atypical swallowing and therefore indirectly increases the likelihood of AOB. While breastfeeding decreases AOB incidence (p = 0.023), bottle feeding increases AOB incidence (p = 0.046). The sobel tests show that the fully mediator variable feature of mouth breathing is statistically significant in the negative relation between zygosity and atypical swallowing. Conclusion: The PLS-SEM model showed that mouth breathing triggers atypical swallowing and atypical swallowing triggers AOB. As a result of this chain of relationships, an indirect effect of zygosity on AOB was observed. According to sobel tests, zygosity has an indirect effect on atypical swallowing through mouth breathing, while mouth breathing has a positive indirect effect on AOB through atypical swallowing. Clinical relevance: This study identified the relationships between different factors and the presence of AOB. The findings of this study demonstrate in detail the relationships between AOB and zygosity, atypical swallowing, mouth breathing, breastfeeding and bottle feeding. Brestfeeding has a reducing effect on the frequency of AOB. Among the nutritional forms, breastfeeding ensures the proper development of the stomatognathic system by working the oro-facial muscles. [ABSTRACT FROM AUTHOR]

Background: The Test of Mastication and Swallowing Solids (TOMASS) is a reliable tool for assessing chewing and swallowing in healthy adults, using commercially available crackers. TOMASS‐Children (TOMASS‐C) is the paediatric version of TOMASS. Objective: The present study aimed to establish normative data for TOMASS‐C using a validated regional commercial cracker among healthy individuals aged between 6–20 years of India. Methods: 327 healthy individuals between 6–20 years were recruited in a cross‐sectional study design following a convenient sampling procedure. Participants consumed one validated regional cracker and the procedure was video recorded. Data were stratified according to age groups (6–7, 8–9, 10–13, 14–17 and 18–20 years) and sex (boys and girls). Two Speech Language Pathologists independently analysed the video recordings to derive discrete bites, masticatory cycles, swallows and total swallow time indices. Using them, time/swallow, masticatory cycles/bite, swallows/bite and time/bite were calculated. Results: All parameters of TOMASS‐C had moderate to good (0.6–0.85) test–retest reliability and moderate to excellent (0.69–0.99) inter‐rater reliability at p >.000. Younger participants took more bites, chewed more times and swallowed more frequently with longer chewing and swallowing time. Boys exhibited a lower number of swallows, shorter swallow time and reduced total masticatory time at p >.05. Additionally, girls demonstrated fewer bites and chewing cycles compared to boys at p >.05. Conclusion: TOMASS‐C using a validated regional cracker was feasible and reliable. Normative data established for healthy boys and girls between 6–20 years offers much‐needed quantitative data to objectively delineate individuals with and without chewing and swallowing solid food difficulties. [ABSTRACT FROM AUTHOR]

The bedside assessment of dysphagia is a crucial method for gaining essential insights into a patient's ability to swallow. This evaluation involves a thorough examination of the patient's medical and swallowing history, a detailed assessment of the anatomy of the mouth, throat, and voice box, and an evaluation of sensory and motor functions, behavior, cognitive abilities, and language skills, along with trying different foods and fluids. Despite being in the early stages of development in Nepal, addressing and treating swallowing disorders are vital efforts. The aim of this study is to document the data obtained from the bedside assessment of dysphagia, using a protocol developed at TUTH. Conducted retrospectively at a tertiary care facility, the evaluation included comprehensive history-taking and trials with food and fluids, along with the use of standardized outcome measures such as the FOIS and RBHOMRS. The results show that 114 out of 121 patients had varying degrees of dysphagia. Therefore, the bedside assessment protocol emerges as a reliable tool for evaluating dysphagia, especially in regions like Nepal where instrumental assessments for swallowing are not yet widely available. [ABSTRACT FROM AUTHOR]

The mechanism behind normal swallowing is complex and multifactorial. Due to the close proximity of the pathways of swallowing and respiration, precise coordination between these functions is vital in order to avoid entry of material into the airway and to ensure optimal health and nutrition in general. Swallowing can be divided into three stages: oral, pharyngeal and oesophageal, and although initiation of the swallow is often under voluntary control, swallowing is also triggered frequently throughout the day as a reflex action due to the presence of saliva in the oropharynx. Dysphagia is a symptom frequently encountered by clinicians and its causes are vast and varied. A thorough understanding of the physiology of swallowing remains necessary to conduct a full assessment and instigate appropriate treatment for these patients in whom dysphagia is often debilitating and may significantly affect their quality of life. We present an account of the physiology of swallowing, illustrated with clinical examples. [ABSTRACT FROM AUTHOR]

Disorders of swallowing are very common and, when looked for, occur regularly in most branches of surgery. Dysphagia is often not the patient's presenting complaint and can be easily missed. The consequences of missed or delayed diagnosis of dysphagia can be insidious but profound and, in some cases, fatal. The investigation and treatment of these patients is normally highly multidisciplinary, potentially involving gastroenterology, general surgery, otolaryngology, acute medicine, stroke medicine, paediatrics, speech and language therapy (SLT) and dietitians. While this article is aimed at surgeons and will thus concentrate mostly on those conditions seen by surgeons, it must be remembered that the most common cause of dysphagia is a neurological disturbance and is managed by physicians and SLT. That said, the incidence of these conditions rises with age, as does the incidence of many surgically treatable conditions. It is therefore common to assess a patient with a known neurological condition for the presence of a second pathology affecting their swallow. A basic knowledge of non-surgical conditions is therefore useful. [ABSTRACT FROM AUTHOR]

Summary: Background and objective: Presbyphagia is defined as structural, physiological and innervational alterations in the swallowing process as a result of aging and is considered to be involved in the etiology of dysphagia. This systematic review and meta-analysis aimed to estimate the prevalence of presbyphagia in older adults without disease-related dysphagia. Methods: In this study five databases were searched in October 2023 with no time limitation. Combined effect sizes of presbyphagia prevalence were calculated using random effect models. Meta-regression and subgroup analyses were conducted to identify sources of heterogeneity. Egger's test and a funnel plot were employed to examine publication bias. Results: A total of 19 studies were selected for analysis. Overall, the prevalence of presbyphagia in older adults was 30.8% (95% confidence interval [CI] 24.8–36.7%). Publication bias was adjusted for using the fill-and-trim method and the corrected pooled prevalence of presbyphagia was 17.3% (95% CI 11.0–23.6%). In addition, the meta-regression findings revealed that the assessment tool had significant effects upon heterogeneity. Conclusion: Although the pooled prevalence of presbyphagia in older adults was 17.3%, the lack of large representative studies limited the interpretation of these findings. In the future, further large studies that diagnose presbyphagia using standardized assessment tools would facilitate new avenues to reduce the risk of dysphagia in older adults. [ABSTRACT FROM AUTHOR]

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Chronic obstructive pulmonary disease (COPD) was previously known as chronic bronchitis and emphysema. It has various main symptoms, such as dyspnea, chronic cough, and sputum, and is often accompanied by dysphagia. Although many published clinical reports have described COPD-related dysphagia, the physiological mechanisms underlying swallowing changes due to COPD remain unclear. Therefore, we analyzed how COPD affects the swallowing reflex using COPD model rats. We performed an electrophysiological study of respiration and swallowing using COPD model induced by intratracheal administration of porcine pancreatic elastase and lipopolysaccharide in Sprague-Dawley male rats. To identify the respiration and swallowing responses, electromyographic activity was recorded from the diaphragm, digastric (Dig), and thyrohyoid (TH) muscles. We confirmed COPD using micro-computed tomography analysis and hematoxylin and eosin staining of the lungs. The duty cycle was defined as the ratio of the inspiration duration to the total respiratory duration. In COPD model rats, the duty cycle was significantly higher than that in control rats. The frequency of the swallowing reflex evoked by electrical stimulation of the superior laryngeal nerve during the inspiration phase was higher in COPD model rats than in control rats. Furthermore, long-term COPD altered Dig and TH muscle activity without pathological muscle change. Our results suggest that COPD increases the frequency of swallowing initiation during the inspiration phase. Furthermore, long-term COPD affects swallowing-related muscle activity without pathological muscle changes. These physiological changes may increase the risk of developing dysphagia. Further studies are necessary to clarify the mechanisms contributing to the functional changes in respiration and swallowing in COPD. [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Conclusion Assessing the internal condition of swallowing‐related muscles and muscle strength and size is important because their deterioration may lead to dysphagia. However, there are few reports on stiffness of swallowing‐related muscles measured using shear‐wave elastography (SWE) and their qualitative characteristics.We measured stiffness of swallowing‐related muscles using SWE to investigate the relationship between muscle stiffness and body composition as well as other relevant variables in healthy adults.Thirty healthy adults were included in this cross‐sectional study. We evaluated stiffness of the genioglossus muscle (GGM) and geniohyoid muscle (GHM) using SWE. Skeletal muscle mass index, body mass index (BMI), handgrip strength, tongue pressure, and cross‐sectional areas of the muscles were measured, and we determined their relationship with muscle stiffness.For muscle stiffness, the mean value for the middle GGM was 7.08 ± 1.92 kPa, that for the posterior GGM was 9.31 ± 2.68 kPa, and that for the GHM was 8.84 ± 2.15 kPa. In multiple regression analysis, with stiffness of the posterior GGM as the dependent variable, BMI (β = −.473, p = .039) was a significant negative explanatory variable. However, with the GHM stiffness as the dependent variable, BMI (β = .419, p = .033) was a significant positive explanatory variable.Stiffness of the posterior GGM was positively correlated with BMI and that of the GHM was negatively correlated with BMI. Stiffness, as measured using SWE, has the potential to capture the intramuscular characteristics of swallowing‐related muscles, particularly the posterior GGM. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Cervical posture affects swallowing function through contractile and non‐contractile structures. Craniocervical flexor endurance training (CCFET), which focuses on the activation of deep cervical muscles, is used to ensure cervical posture stability. Objective: The aim of this study was to investigate the effect of CCFET on the suprahyoid muscles (SH), which play an important role in swallowing function. Methods: Eighty healthy individuals (52 female and 28 male, mean age 21.77 ± 1.81 years) were recruited and randomly assigned to groups that underwent either deep cervical flexor (DCF) training with a pressure biofeedback unit (CCFET group, n = 41) or no intervention (control group, n = 39). The intervention was applied for 4 weeks (five sessions per week). Static endurance and activation of DCF muscles (Craniocervical Flexion Test, CCFT), tragus–wall distance (TWD) for forward head posture and surface electromyographic (sEMG) activation of suprahyoid muscles were evaluated. Results: The endurance and activation of the DCF muscles were significantly increased in the CCFET group (p = <.001). In the CCFET group, TWD significantly lower than the control group (p = <.001) Peak SH amplitude and mean SH amplitude were lower in the CCFET group compared to the control group (p =.013, p =.003). Conclusion: The study shows that 4 weeks of CCFET reduced SH muscle activation, allowing the same work to be done with fewer motor units. CCFET can be included in rehabilitation programs as an additional method that has an effect on the muscles involved in swallowing by providing cervical motor control. [ABSTRACT FROM AUTHOR]

Background: Postextubation dysphagia (PED) is a common complication to endotracheal intubation in critically ill patients and may lead to pneumonia, prolonged ventilation, longer hospital stays, and increased mortality. Recognizing dysphagia is paramount to preventing adverse events. The aim of this study was to describe PED management by investigating practice in Danish intensive care units (ICUs) focusing on current practice in 2023 (screening, prevention, and treatment), perceived best practice (barriers and facilitators), and when possible, to compare practice in 2017 and 2023. Methods: Self‐reported, cross‐sectional survey of dysphagia practice in Danish ICUs administered from April to May 2023. In addition, data were compared with the 2017 Dysphagia in Intensive Care Evaluation study, when possible. Results: Only half of Danish ICUs reported to have a PED protocol, and less than half routinely screen patients for dysphagia after extubation. Most common screening methods were the oral mechanism examination, water test, and Facio‐oral tract therapy. Nurses and physicians often relied on an overall physical assessment of the patient. Best treatment methods were uniformly agreed to be patient positioning, modification of food and fluids, use of ergonomic utensils, and compensatory maneuvers. Key barriers to dysphagia management were lack of specialized staff, under‐recognition of dysphagia as a health issue, and lack of standardized protocols. Conclusion: Awareness of PED is increasing and identification, prevention, and treatment is slowly improving, but systematic implementation of protocols for dysphagia screening and treatment could enhance dysphagia management in Danish ICUs. [ABSTRACT FROM AUTHOR]

Purpose: We investigated the association between the time to first post-extubation oral intake, barriers to oral intake, and the rate of activities of daily living (ADL) independence at discharge (Barthel Index score <70). Method: Consecutive patients admitted to the intensive care unit, aged ≥18 years, and mechanically ventilated for ≥48 hr were retrospectively enrolled. The time to first oral intake, barriers to oral intake, daily changes, and clinical outcomes were assessed. Multiple logistic regression analysis adjusted for baseline characteristics was used to determine the association between time to first post-extubation oral intake and ADL independence. Result: Among the 136 patients, 74 were assigned to the ADL independence group and 62 to the dependence group. The time to first post-extubation oral intake was significantly associated with ADL independence (adjusted p = < 0.001) and was a predictor of ADL independence at discharge. Respiratory and dysphagia-related factors (odds ratio [OR] 0.35; 95% confidence interval [CI] 0.15–0.82, p = 0.015 and OR 0.07; CI 0.01–0.68, p = 0.021, respectively) were significantly associated with the ADL independence at discharge. Conclusion: Respiratory and dysphagia-related factors, as barriers to the initiation of oral intake after extubation, were significantly associated with ADL independence at discharge. [ABSTRACT FROM AUTHOR]

Purpose: This systematic review evaluated the efficacy of therapeutic interventions on improving swallow, respiratory, and cough functions in Parkinson's disease (PD). Method: A PRISMA systematic search was implemented across six databases. We selected studies reporting pre- and post-assessment data on the efficacy of behavioural therapies with a swallow or respiratory/cough outcome, and excluded studies on medical/surgical treatments or single-session design. Cross-system outcomes across swallow, respiratory, and cough functions were explored. Cochrane's risk of bias tools were utilised to evaluate study quality. Result: Thirty-six articles were identified and further clustered into four treatment types: swallow related (n = 5), electromagnetic stimulation (n = 4), respiratory loading (n = 20), and voice loading (n = 7) therapies. The effects of some behavioural therapies were supported with high-quality evidence in improving specific swallow efficiency, respiratory pressure/volume, and cough measures. Only eleven studies were rated with a low risk of bias and the remaining studies failed to adequately describe blinding of assessors, missing data, treatment adherence, and imbalance assignment to groups. Conclusion: Behavioural therapies were diverse in nature and many treatments demonstrated broad cross-system outcome benefits across swallow, respiratory, and cough functions. Given the progressive nature of the condition, the focus of future trials should be evaluating follow-up therapy effects and larger patient populations, including those with more severe disease. [ABSTRACT FROM AUTHOR]

Thousands of rescued harbor seals (Phoca vitulina) require rehabilitation worldwide. Many require resource intensive gavage feeding due to abandonment soon after birth. Little is known about seal swallowing, therefore, our primary objective was to determine the feasibility of conducting videofluoroscopic swallowing studies (VFS) on seal pups prior to their release. Secondarily, we propose swallowing phase descriptions. We adapted a VFS approach used in humans and our feasibility parameters included: bolus detection and consumption, and number of analyzable swallowing events. Unrestrained seals were imaged in a dry environment using a Siemens mobile c-arm fluoroscopy unit. Oral boluses were thawed herring injected with liquid barium suspension (105% w/v). Two independent raters described swallows using a standardized approach with results summarized descriptively. We successfully completed freely-behaving VFS with two infant seals (1 male: 8 wks, 3 d; 1 female: 5 wks, 3 d). Both consumed five boluses with six fully analyzable swallowing events. We describe four swallow phases: preparatory, prehension, oropharyngeal and esophageal. Airway protection likely occurs in two ways: (1) during the preparatory phase through modified corniculate cartilage contact with the glottis and (2) with soft palate contact to the base of tongue prior to swallow initiation. We have conducted a unique VFS approach on rehabilitated seals, prior to their release. We have described airway protection and suggest that swallowing is initiated earlier in the feeding process than described previously. This protocol success will afford: (1) collection of normative swallowing data, and (2) future knowledge translation from humans to seals. [ABSTRACT FROM AUTHOR]

This study aimed to identify the neuroanatomical predictors of oropharyngeal dysphagia and tube dependency in patients with supratentorial or infratentorial ischemic strokes. Patients with acute ischemic stroke were enrolled and were classified into 3 groups: right supratentorial (n = 61), left supratentorial (n = 89), and infratentorial stroke (n = 50). Dysphagia was evaluated by a modified water swallowing test and the Food Intake LEVEL Scale to evaluate oropharyngeal dysphagia and tube dependency, respectively. As two dysphagia parameters, we evaluated the durations from onset of stroke to (1) success in the modified water swallowing test and to (2) rating 7 points or above on the Food Intake LEVEL Scale: patients regained sufficient oral intake and were not tube-dependent. Voxel-based lesion-symptom mapping analysis was performed for a spatially normalized lesion map of magnetic resonance imaging to explore the anatomies that are associated with the two dysphagia parameters for each stroke group. The right precentral gyrus and parts of the internal capsule are associated with oropharyngeal dysphagia. The four supratentorial areas are associated with tube dependency. The dorsal upper medulla is associated with both oropharyngeal dysphagia and tube dependency. These results suggest that supratentorial stroke patients can be tube-dependent due to an impaired anticipatory phase of ingestion. The simultaneous damage in the four supratentorial areas: the inferior part of the precentral gyrus, lenticular nucleus, caudate head, and anterior insular cortex, predicts tube dependency. In contrast, infratentorial stroke patients can be tube-dependent due to oropharyngeal dysphagia caused by lesions in the dorsal upper medulla, damaging the swallowing-related nucleus. [ABSTRACT FROM AUTHOR]

Background: Integrated speech-language pathology (SLP) services within the emergency department (ED) may facilitate timely dysphagia management. However, there are multiple patient and logistical factors specific to the ED that challenge the delivery of optimal dysphagia referral and management practices within this setting. The aim of the current study was to engage a stakeholder group to identify prioritised, actionable goals that could help enhance dysphagia management within the ED. Methods and Procedures: Applying concept mapping methodology, 16 ED stakeholders from SLP, medical, nursing, and leadership participated in semi-structured interviews to develop action statements which were sorted and ranked for importance and changeability. Multidimensional scaling and hierarchical cluster analysis were used to organise data in clusters with unifying themes before statements were ranked by importance and changeability. Outcomes and Results: Stakeholders identified 53 unique statements, grouped into 8 clusters. Review of the 8 clusters identified 3 overarching aspects for change: (a) Improving processes related to identification and referral of patients as well as communication; (b) Teamwork and collaboration amongst the ED multidisciplinary team and SLP; and (c) Improving staffing and access to training resources for SLP and nursing teams. Seventeen statements were within the Go-zone rated highest for importance and changeability) with the highest rated statement being: Clear documentation by SLP re: recommendations. Conclusion: The current data identified multiple aspects of service provision that require change to facilitate improved dysphagia referral and management services in the ED. Collaborative actions are required by both SLP and the ED multidisciplinary team to help optimise dysphagia services. [ABSTRACT FROM AUTHOR]

This aim of this study is to characterize the nature and pathophysiology of dysphagia after ACDF surgery by precisely and comprehensively capturing within-subject changes on videofluoroscopy between preoperative and postoperative time points. 21 adults undergoing planned primary ACDF procedures were prospectively recruited and enrolled. Participants underwent standardized preoperative and six-week postoperative videofluoroscopic swallow studies. Videos were blindly rated using the Penetration-Aspiration Scale (PAS) and analysis of total pharyngeal residue (%C2-42), swallowing timing, kinematics, and anatomic change was completed. Linear mixed-effects modeling was used to explore the relationships between possible predictor variables and functional outcomes of interest that changed across timepoints. There was no change in PAS scores across timepoints. Total pharyngeal residue (%C2-C42) was increased postoperatively (p < 0.001). Our statistical model revealed significant main effects for timepoint (p = 0.002), maximum pharyngeal constriction area (MPCAN) (p < 0.001), and maximum thickness of posterior pharyngeal (PPWTMAX) (p = 0.004) on the expression of total pharyngeal residue. There were significant two-way interactions for timepoint and MPCAN (p = 0.028), timepoint and PPWTMAX (p = 0.005), and MPCAN and PPWTMAX (p = 0.010). Unsurprisingly, we found a significant three-way interaction between these three predictors (p = 0.027). Our findings suggest that in planned ACDF procedures without known complications, swallowing efficiency is more likely to be impaired than airway protection six weeks after surgery. The manifestation of impaired swallowing efficiency at this timepoint appears to be driven by a complex relationship between reduced pharyngeal constriction and increased prevertebral edema. [ABSTRACT FROM AUTHOR]

The last two decades have seen increasing use of long-term ventilation (LTV) as an intervention in childhood. Children who use LTV have many risk factors for feeding and swallowing difficulties, including their underlying respiratory and/or neurological etiology, long hospitalizations, medical interventions, and limited exposure to oral feeding experiences. This review aimed to answer two questions: 1) 'What specific swallowing and feeding characteristics do these children experience?'; and 2) 'What impacts do these swallowing and feeding characteristics have on health status and quality of life?'. Texts were identified across bibliographic databases, reference lists, and grey literature. Studies were analyzed according to ventilation, feeding and swallowing, assessment and intervention, and quality of life parameters. Overall, 1919 papers were screened, with 31 papers included in the final data extraction process. A range of feeding and swallowing characteristics were observed, including oral secretion management difficulties, oral aversion, swallowing difficulties, and clinical signs of aspiration. Non-oral feeding was found to be the primary feeding method used. Little information on health status and quality of life was reported in scoping review texts. Children with LTV needs present with a range of feeding and swallowing concerns, and non-oral feeding is common. Further research is needed to understand the feeding and swallowing journey of this population. This will assist in future service planning and delivery, and in turn contribute to improving patient outcomes and quality of life. [ABSTRACT FROM AUTHOR]

The pterygomandibular raphe (PMR) is a tendinous bundle between the bucinator (BM) and the superior constrictor of pharynx (SC) and has been considered essential for swallowing. Despite its functional significance, previous studies reported that the PMR is not always present. Another study reported presence of the connecting fascia between the BM and deep temporalis tendon (dTT). Therefore, the present study analyzed the three-dimensional relationship between the BM, SC, and dTT. We examined 13 halves of 11 heads from adult Japanese and Caucasian cadavers: eight halves macroscopically and five halves histologically. There was no clear border between the BM and SC in any specimens macroscopically. The BM attachment varied depending on its levels. At the level of the superior part of the internal oblique line, the BM fused with the SC with no clear border. At the level of the midpart of the internal oblique line of the mandible, the BM attached to the dTT directly, and the SC attached to the dTT via collagen fibers and the BM. Based on these results, these muscles should be described as the BM/dTT/SC (BTS) complex. The three-dimensional relationship of the BTS complex might result in the so-called "pterygomandibular raphe." The BTS complex could be important as a muscle coordination center in chewing and swallowing. [ABSTRACT FROM AUTHOR]

The PRO-ACTIVE randomized clinical trial offers 3 swallowing therapies to Head and Neck Cancer (HNC) patients during radiotherapy namely: reactive, proactive low- ("EAT-RT" only), and high-intensity ("EAT-RT + exercises"). Understanding the perceived acceptability of these interventions is important to inform eventual implementation into clinical practice. This study explored patients' perspectives using qualitative methodology. At 2 Canadian PRO-ACTIVE trial sites, 24 trial participants were recruited for individual semi-structured interviews, representing each of the 3 trial arms. Data collection and thematic analysis were guided by the Theoretical Framework of Acceptability (TFA). Member checking was conducted through follow-up focus groups. Seven themes were derived reflecting the TFA constructs. Overall, regardless of trial arm, patients reported a positive experience with therapy. Patients identified benefits of EAT-RT therapy, reporting that it provided meaningful feedback on diet progress and supported goal setting for oral intake. Patients who received proactive therapies valued the opportunity to set expectations early, build mealtime routine iteratively over time, and have an extended engagement with the SLP. Regardless of trial arm, patients agreed proactive therapy aligned with what they think is best and that therapy intensity should accommodate individual needs. This study identified the value to HNC patients of receiving swallowing interventions during RT and setting realistic expectations around swallowing. Compared to reactive care, proactive therapies were perceived helpful in consolidating habits early, establishing realistic expectations around swallowing and building an extended rapport with the SLP. These findings will inform the implementation of proactive versus reactive swallowing therapies in clinical practice. [ABSTRACT FROM AUTHOR]

Objectives: Cervical chordoma is a rare, low‐grade primary bone tumor occurring in the axial skeleton. Due to challenges in surgical exposure caused by anatomic location, patients may experience dysfunction in speech and swallowing. The objective of this study was to characterize speech and swallowing outcomes for patients undergoing surgical resection of cervical chordoma. Moreover, we detail in‐depth two cases with similar initial presentations to compare prognostic factors and management strategies. Methods: Eleven patients with histologically confirmed cervical chordoma treated between 1993 and 2020 were included in this retrospective case series. Outcomes measured included overall survival, disease‐free survival, need for enteral feeds, as well as results of modified barium swallow study (MBSS) and fiberoptic laryngoscopy. Results: The mean age at diagnosis was 55.9 years. The patient population was 81.8% male. Mean survival after diagnosis was 96 months. Four (36.4%) patients required post‐operative MBSS and demonstrated aspiration. All four of these patients presented with tumors in the superior cervical spine and received surgeries utilizing anterior approaches. Of the four, 2 required enteral feeds long‐term. Four (36.4%) patients endorsed dysphonia. One patient developed post‐operative right vocal fold paresis. The remaining three patients experienced stable dysphonia pre‐ and post‐operatively. Additionally, three (27%) patients required tracheostomy placement, two of which remained in place long‐term. Conclusions: Dysphagia is a common side effect of cervical chordoma resection. It is associated with the use of an anterior approach during resection and with tumors located in the superior cervical spine. Patients with postoperative dysphagia should receive early multidisciplinary swallow rehabilitation. Level of Evidence: 4 Laryngoscope, 134:3706–3712, 2024 [ABSTRACT FROM AUTHOR]

BackgroundMyotomy length in type 3 achalasia is generally tailored based on segment of spasticity on high-resolution manometry (HRM). Potential of length of tertiary contractions on barium esophagram (BE) or length of thickened circular muscle on endoscopic ultrasound (EUS) to guide tailored myotomy is less understood. This study aimed to assess agreement between spastic segments lengths on HRM, BE, and EUS among patients with type 3 achalasia.MethodsThis retrospective study included adults with type 3 achalasia on HRM between November 2019 and August 2022 who underwent evaluation with EUS and/or BE. Spastic segments were defined as HRM-distance between proximal borders of lower esophageal sphincter and high-pressure area (isobaric contour ≥70 mmHg); EUS-length of thickened circular muscle (≥1.2 mm) from proximal border of esophagogastric junction (EGJ) to the transition to a non-thickened circular muscle; BE-distance between EGJ to proximal border of tertiary contractions. Pairwise comparisons assessed for correlation (Pearson's) and intraclass correlation classification (ICC) agreement.Key resultsTwenty-six patients were included: mean age 66.9 years (SD 13.8), 15 (57.7%) male. Spastic segments were positively correlated on HRM and BE with good agreement (ICC 0.751, [95% CI 0.51, 0.88]). Spastic segments were negatively correlated with poor agreement on HRM and EUS (ICC -0.04, [-0.45, 0.39]) as well as BE and EUS (ICC -0.03, [-0.47, 0.42]).Conclusions & inferencesLength of spastic segment was positively correlated on HRM and BE while negatively correlated when compared to EUS, supporting the common use of HRM and highlighting the uncertain role for EUS in tailoring myotomy length for type 3 achalasia.

Swallowing is a complex neuromuscular activity regulated by the autonomic central nervous system, and impairment can lead to dysphagia, which is difficulty in swallowing. This research presents a novel approach that utilizes wireless, wearable technology for the continuous mechano-acoustic tracking of respiratory activities and swallowing. To address the challenge of accurately tracking swallowing amidst potential confounding activities or significant body movements, we employ two accelerometers. These accelerometers help distinguish between genuine swallowing events and other activities. By monitoring movements and vibrations through the skin surface, the developed device enables non-intrusive monitoring of swallowing dynamics and respiratory patterns. Our focus is on the development of both the wireless skin-interfaced device and an advanced algorithm capable of detecting swallowing dynamics in conjunction with respiratory phases. The device and algorithm demonstrate robustness in detecting respiratory patterns and swallowing instances, even in scenarios where users exhibit periodic movements due to disease or daily activities. Furthermore, peak detection using an adaptive threshold automatically adjusts to an individual’s signal strength, facilitating the detection of swallowing signals without the need for individual adjustments. This innovation has significant potential for enhancing patient training and rehabilitation programs aimed at addressing dysphagia and related respiratory issues.

Abstract 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) 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.

Background: Cervical auscultation (CA) involves listening to swallowing and respiratory sounds and/or vibrations to detect oropharyngeal aspiration (OPA). CA has shown promising diagnostic test accuracy when used with the clinical swallowing examination and is gaining popularity in clinical practise. There has not been a review to date analysing the accuracy of CA in paediatric and adult populations with meta‐analyses. Objectives: To determine the accuracy of CA in detecting OPA in paediatric and adult populations, when compared to instrumental assessments. Search Methods: Databases searched included MEDLINE, PubMed, Embase, CINAHL, AustHealth, Cochrane and Web of Science. The search was restricted between 01 October 2012 and 01 October 2022. Selection Criteria: Inclusion criteria included (a) all clinical populations of all ages, (b) who have had an instrumental assessment and (c) CA. All study types were included. Data Collection and Analysis: Studies were reviewed independently by two authors. The methodological quality of the studies was analysed using the QUADAS‐2. Main Results: Ten studies met the inclusion criteria for this review and meta‐analyses. The pooled diagnostic performance of CA in detecting OPA was 0.91 for sensitivity and 0.79 for specificity. The area under the curve summary receiver operating curve (sROC) was estimated to be 0.86, thereby indicating good discrimination of OPA. Most studies scored high for risk of bias in at least one domain in the QUADAS‐2, likely attributed to a lack of high‐quality prospectively designed studies. Conclusions: There are promising diagnostic test accuracies for the use of CA in detection of OPA. Future research could include using CA in specific clinical populations and settings, and identifying standardised criteria for CA. [ABSTRACT FROM AUTHOR]

Abstract Background Swallowing is a complex process that requires the coordination of muscles in the mouth, pharynx, larynx, and esophagus. Dysphagia occurs when a person has difficulty swallowing. In the case of subjects with respiratory diseases, the presence of oropharyngeal dysphagia potentially increases lung disease exacerbations, which can lead to a rapid decline in lung function. This study aimed to analyze the swallowing of patients with idiopathic pulmonary fibrosis (IPF). Methods Patients with IPF were evaluated using the Eating Assessment Tool (EAT-10), tongue pressure, the Timed Water Swallow Test (TWST), and the Test of Mastication and Swallowing Solids (TOMASS). The findings were related to dyspnea severity assessed by the modified Medical Research Counsil (mMRC) score; the nutritional status screened with Mini Nutritional Assessment (MNA) tool; and pulmonary function tests, specifically spirometry and measurement of the diffusing capacity for carbon monoxide (DLCO), the maximal inspiratory pressure (PImax), and the maximal expiratory pressure (PEmax). Results The sample consisted of 34 individuals with IPF. Those who exhibited swallowing modifications scored lower on the MNA than those who did not (9.6 ± 0.76 vs. 11.64 ± 0.41 points; mean difference 1.98 ± 0.81 points; p = 0.02). They also showed poorer lung function when considering the predicted force vital capacity (FVC; 81.5% ± 4.61% vs. 61.87% ± 8.48%; mean difference 19.63% ± 9.02%; p = 0.03). The speed of liquid swallowing was altered in 31of 34 of the evaluated subjects (91.1%). The number of liquid swallows correlated significantly with the forced expiratory volume in 1 s (FEV1)/FVC ratio (r = 0.3; p = 0.02). Solid eating and swallowing assessed with the TOMASS score correlated with lung function. The number of chewing cycles correlated negatively with PImax% predicted (r = -0.4; p = 0.0008) and PEmax% predicted (r = -0.3; p = 0.02). FVC% predicted correlated with increased solid swallowing time (r = -0.3; p = 0.02; power = 0.6). Swallowing solids was also impacted by dyspnea. Conclusion Patients with mild-to-moderate IPF can present feeding adaptations, which can be related to the nutritional status, lung function, and the severity of dyspnea.

Abstract Monitoring of ingestive activities is critically important for managing the health and wellness of individuals with various health conditions, including the elderly, diabetics, and individuals seeking better weight control. Monitoring swallowing events can be an ideal surrogate for developing streamlined methods for effective monitoring and quantification of eating or drinking events. Swallowing is an essential process for maintaining life. This seemingly simple process is the result of coordinated actions of several muscles and nerves in a complex fashion. In this study, we introduce automated methods for the detection and quantification of various eating and drinking activities. Wireless surface electromyography (sEMG) was used to detect chewing and swallowing from sEMG signals obtained from the sternocleidomastoid muscle, in addition to signals obtained from a wrist-mounted IMU sensor. A total of 4675 swallows were collected from 55 participants in the study. Multiple methods were employed to estimate bolus volumes in the case of fluid intake, including regression and classification models. Among the tested models, neural networks-based regression achieved an R 2 of 0.88 and a root mean squared error of 0.2 (minimum bolus volume was 10 ml). Convolutional neural networks-based classification (when considering each bolus volume as a separate class) achieved an accuracy of over 99% using random cross-validation and around 66% using cross-subject validation. Multiple classification methods were also used for solid bolus type detection, including SVM and decision trees (DT), which achieved an accuracy above 99% with random validation and above 94% in cross-subject validation. Finally, regression models with both random and cross-subject validation were used for estimating the solid bolus volume with an R 2 value that approached 1 and root mean squared error values as low as 0.00037 (minimum solid bolus weight was 3 gm). These reported results lay the foundation for a cost-effective and non-invasive method for monitoring swallowing activities which can be extremely beneficial in managing various chronic health conditions, such as diabetes and obesity.

Background Objective Methods Results Conclusions Oral food processing is an important part of daily food intake. A major part of this process is mastication, which prepares a bolus of food for swallowing by mechanically crushing and grinding ingested food between the teeth using rhythmic movements. Masticatory dysfunction is common in the elderly and in some neurological disorders and can have serious negative health consequences.This study investigated the effect of restricted mastication, achieved by experimentally reducing the duration of mastication, on masticatory patterns and subsequent swallowing function.Thirty healthy men (25 ± 3 years old) were instructed to chew gum jelly with a free mastication duration (G100), a half and a quarter duration of G100. Masseter and digastric electromyographic (EMG) activity was recorded to assess mastication and swallowing activity, respectively. In addition, the acceleration of the thyroid cartilage ridge was measured with an accelerometer. The root mean square (RMS) of muscle EMG activity in the masseter and digastric muscles, the number of masseter EMG bursts, time to peak and total duration of each masseter EMG burst, swallowing duration and laryngeal elevation latency were analysed.Restricting masticatory duration reduced the number of mastication cycles (p < .001), prolonged the time to peak (p < .001) and total duration of masseter EMG bursts (p < .001) and resulted in an overall increased RMS score of masseter muscle activity (p = .017). Furthermore, restricted masticatory duration led to a decrease in both swallowing duration (p = .001) and laryngeal elevation latency (p = .012), with a significant increase in the RMS score of digastric muscle activity (p < .001).Under the experimental conditions of restricted mastication, several adaptation features were observed, including changes in masticatory cycle characteristics and swallowing duration. Thus, although the overall masticatory efficiency was reduced, these adaptations allowed healthy individuals to still swallow safely. [ABSTRACT FROM AUTHOR]

Background Aim Methods & Procedures Outcomes & Results Main Contribution Conclusions & Implications WHAT THIS PAPER ADDS What is already known on the subject What this study adds to the existing knowledge What are the potential or actual clinical implications of this work? Based on stakeholder conversations, speech and language therapists have anecdotally observed cases of dysphagia with suspected laryngeal hypersensitivity. These presentations have been coined as ‘muscle tension dysphagia’ often with concurrent laryngeal sensitivity symptoms. However, the role of laryngeal hypersensitivity in dysphagia is not fully understood. Knowledge user engagement highlights a lack of clarity around diagnosis and investigative approaches, limited clinical guidance and inconsistent practice, which leads to inequity in service delivery and care.To identify and present the published literature regarding the definitions and clinical identification tools used during the management of laryngeal hypersensitivity related dysphagia.A scoping review was conducted following Joanna Briggs Institute methodology and EQUATOR PRISMA‐ScR guidance. Patient and stakeholder engagement was embedded at each review stage. The protocol was registered with the Open Science Framework: DOI 10.17605/OSF.IO/CUXYN. A multidatabase search strategy identified literature published between 2012 and 2022. A narrative description was used to report the study findings.The search identified 2590 citations. The full paper screening was completed on 88 studies, with 17 studies included in data extraction. There was a wide range of terminology and assessment approaches which varied across different clinical settings. The most cited term was ‘muscle tension dysphagia’. The most common assessments tools were videofluoroscopy, fibreoptic endoscopic evaluation of swallowing and videostroboscopy, predominantly used in speech and language therapy and/or Ear, Nose and Throat settings. Gastroesophageal and respiratory investigations were less frequently cited.This review details the current evidence related to the terminology and assessment tools cited in laryngeal hypersensitivity related dysphagia to improve clinician knowledge and understanding. Patient and stakeholder involvement indicated that future research needs to: optimize consensus of terminology, and improve consistent identification methods, service provision and treatment approaches.This review highlights the lack of consistent terminology across the literature. A wide range of assessment tools report nonspecific positive clinical features and a lack of significant instrumental assessment findings. Patients and stakeholders identify the research priorities should improve clinician awareness, knowledge, guidance and evidence to support patient care. Swallowing difficulties can occur in adults for a number of different reasons, such as neurological, respiratory or physiological conditions. Swallowing difficulties with no evidence of biomechanical or structural impairment on instrumental assessment and of unknown cause (termed idiopathic functional dysphagia or medically unexplained dysphagia) is a poorly understood phenomenon. More recently, concurrent oropharyngeal dysphagia and laryngeal hypersensitivity and/or muscle tension have been posited as a potential underlying mechanism. This scoping review contributes to our expanding knowledge of the role of laryngeal hypersensitivity in dysphagia by providing an overview of the current evidence related to the terminology and assessment tools reported in the literature. Embedded patient and stakeholder involvement further deepens real‐world insights into the increased referrals for these individuals with increasing uncertainty in how to best assess, manage and support patients. Patients equally have reported that reduced professional awareness and inequalities in service delivery pathways result in poor patient experience and quality of life, and healthcare economic burden. This scoping review draws our attention to an area of practice which has received little attention in both clinical practice and academic research. First, the study raises awareness of this population and the impact for services, speech and language therapists and clinicians; and second, highlights evidence–practice gaps with seldom consistency in the use of terminology and assessment approaches. The study provides priority research themes to expand our knowledge and understanding, as guided by the literature and patient and stakeholder input. [ABSTRACT FROM AUTHOR]

Texture modified consistencies (TMC) is a common compensatory strategy in dysphagia management. Lack of consensus regarding TMC terminology places a person at risk of poor oral intake, malnutrition, dehydration, and aspiration. To investigate: (a) Swedish Speech-Language Pathologists (SLPs) dysphagia management with TMC, including terminology, inter-professional collaboration, and knowledge of standard TMC guides; and (b) the current TMC terminology/guides used within university hospitals, in Sweden. Part One surveyed SLPs from 19/21 regions. Recruitment occurred via regional SLP/department managers, the national SLP association and email lists. Non-parametric statistics were employed. Part Two explored TMC guides within the seven university hospitals. The initial survey identified 78 Swedish TMC terms. Overlap of both TMC terms and descriptions occurred. Different terms to describe same/similar textures were used by 70% of the SLPs. Knowledge of established guides was high (>90%), though TMC was often (60%) based on locally developed documents. Collaboration with other professions was reported by 97% of SLPs, however almost half perceived collaboration to be inadequate, citing difficulties with transfer of TMC recommendations. Variance in TMC terms/guides within/across the university hospitals occurred. Variable TMC terminology is used in Sweden, impacting optimal dysphagia management. Future research should focus upon implementation of standardised TMC terminology. [ABSTRACT FROM AUTHOR]

Introduction/Aims: Evaluations of pulmonary, cough, and swallow function are frequently performed to assess disease progression in amyotrophic lateral sclerosis (ALS), yet the relationship between these functions remains unknown. We therefore aimed to determine relationships between these measures in individuals with ALS. Methods: One hundred individuals with ALS underwent standardized tests: forced vital capacity (FVC), maximum expiratory/inspiratory pressure (MEP, MIP), voluntary cough peak expiratory flow (PEF), and videofluoroscopic swallow evaluation (VF). Duplicate raters completed independent, blinded ratings using the Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scale. Descriptives, Spearman's Rho correlations, Kruskal–Wallis analyses, and Pearson's chi‐squared tests were completed. Results: Mean and standard deviation across pulmonary and cough measures were FVC: 74.2% predicted (± 22.6), MEP: 91.6 cmH2O (± 46.4), MIP cmH2O: 61.1 (± 28.9), voluntary PEF: 352.7 L/min (± 141.6). DIGEST grades included: 0 (normal swallowing): 31%, 1 (mild dysphagia): 48%, 2 (moderate dysphagia): 10%, 3 (severe dysphagia): 10%, and 4 (life‐threatening dysphagia): 1%. Positive correlations were observed: MEP‐MIP: r =.76, MIP‐PEF: r =.68, MEP‐PEF: r =.61, MIP‐FVC: r =.60, PEF‐FVC: r =.49, and MEP‐FVC: r =.46, p <.0001. MEP (p =.009) and PEF (p =.04) differed across DIGEST safety grades. Post hoc analyses revealed significant between group differences in MEP and PEF across DIGEST safety grades 0 versus 1 and grades 0 versus 3, (p <.05). Discussion: In this cohort of individuals with ALS, pulmonary function, and voluntary cough were associated. Expiratory metrics (MEP, PEF) were diminished in individuals with unsafe swallowing, increasing their risk for effectively defending the airway. [ABSTRACT FROM AUTHOR]

Velopharyngeal insufficiency (VPI) is a form of velopharyngeal dysfunction caused by abnormal or insufficient anatomy. This process is known to be associated with dysphagia and dysphonia but surgical interventions for these complex patients have not been well studied. The current study characterized a small cohort of adult patients with acquired VPI, dysphonia, and dysphagia, as well as associated surgical interventions. A retrospective descriptive case series of 22 (N = 22) adult patients over a 6-year period with acquired VPI and varying degrees of dysphagia and dysphonia was described from a multi-disciplinary voice and swallowing clinic. Perceptual assessment, nasopharyngoscopy, fluoroscopic swallowing assessment, and patient reported outcomes were reviewed to characterize the cohort. VPI etiologies included: stroke (n = 4), head and neck cancer (n = 5), brainstem lesions (n = 5), trauma (n = 5), and other/unknown (n = 3). All 22 patients underwent nasopharyngoscopy and were categorized as having unilateral (n = 13), central (n = 4), or no (n = 5) velopharyngeal deficits. Seventeen patients (77.2%) underwent modified barium swallow studies, revealing that soft palate elevation scored least impaired among patients with no VPI, and most impaired among patients with unilateral VPI deficits. All 22 patients underwent some form of surgical intervention for VPI, with 14 (63.6%) of those patients requiring additional surgical revision. This series is one of the first to the authors' knowledge to characterize a cohort of individuals with VPI, dysphagia, and dysphonia and associated surgical interventions. [ABSTRACT FROM AUTHOR]

Introduction: Swallowing impairment is a crucial issue that can lead to aspiration, pneumonia, and malnutrition. Animal models are useful to reveal pathophysiology and to facilitate development of new treatments for dysphagia caused by many diseases. The present study aimed to develop a new dysphagia model with reduced pharyngeal constriction during pharyngeal swallowing. Methods: We analyzed the dynamics of pharyngeal swallowing over time with the pharyngeal branches of the vagus nerve (Ph-X) bilaterally or unilaterally transected, using videofluoroscopic assessment of swallowing in guinea pigs. We also evaluated the detailed anatomy of the pharyngeal constrictor muscles after the denervation. Results: Videofluoroscopic examination of swallowing showed a significant increase in the pharyngeal area during swallowing after bilateral and unilateral sectioning of the Ph-X. The videofluoroscopy also showed significantly higher pharyngeal transit duration for bilateral and unilateral section groups. The thyropharyngeal muscle on the sectioned side was significantly thinner than that on the intact side. In contrast, the thickness of the cricopharyngeal muscles on the sectioned and intact sides were not significantly different. The mean thickness of the bilateral thyropharyngeal muscles showed a linear correlation to the pharyngeal area and pharyngeal transit duration. Discussion: Data obtained in this study suggest that denervation of the Ph-X could influence the strength of pharyngeal contraction during pharyngeal swallowing in relation to thickness of the pharyngeal constrictor muscles, resulting in a decrease in bolus speed. This experimental model may provide essential information (1) for the development of treatments for pharyngeal dysphagia and (2) on the mechanisms related to the recovery process, reinnervation, and nerve regeneration following injury and swallowing impairment possibly caused by medullary stroke, neuromuscular disease, or surgical damage from head and neck cancer. [ABSTRACT FROM AUTHOR]

Background: Swallowing is a complex process that requires the coordination of muscles in the mouth, pharynx, larynx, and esophagus. Dysphagia occurs when a person has difficulty swallowing. In the case of subjects with respiratory diseases, the presence of oropharyngeal dysphagia potentially increases lung disease exacerbations, which can lead to a rapid decline in lung function. This study aimed to analyze the swallowing of patients with idiopathic pulmonary fibrosis (IPF). Methods: Patients with IPF were evaluated using the Eating Assessment Tool (EAT-10), tongue pressure, the Timed Water Swallow Test (TWST), and the Test of Mastication and Swallowing Solids (TOMASS). The findings were related to dyspnea severity assessed by the modified Medical Research Counsil (mMRC) score; the nutritional status screened with Mini Nutritional Assessment (MNA) tool; and pulmonary function tests, specifically spirometry and measurement of the diffusing capacity for carbon monoxide (DLCO), the maximal inspiratory pressure (PImax), and the maximal expiratory pressure (PEmax). Results: The sample consisted of 34 individuals with IPF. Those who exhibited swallowing modifications scored lower on the MNA than those who did not (9.6 ± 0.76 vs. 11.64 ± 0.41 points; mean difference 1.98 ± 0.81 points; p = 0.02). They also showed poorer lung function when considering the predicted force vital capacity (FVC; 81.5% ± 4.61% vs. 61.87% ± 8.48%; mean difference 19.63% ± 9.02%; p = 0.03). The speed of liquid swallowing was altered in 31of 34 of the evaluated subjects (91.1%). The number of liquid swallows correlated significantly with the forced expiratory volume in 1 s (FEV1)/FVC ratio (r = 0.3; p = 0.02). Solid eating and swallowing assessed with the TOMASS score correlated with lung function. The number of chewing cycles correlated negatively with PImax% predicted (r = -0.4; p = 0.0008) and PEmax% predicted (r = -0.3; p = 0.02). FVC% predicted correlated with increased solid swallowing time (r = -0.3; p = 0.02; power = 0.6). Swallowing solids was also impacted by dyspnea. Conclusion: Patients with mild-to-moderate IPF can present feeding adaptations, which can be related to the nutritional status, lung function, and the severity of dyspnea. [ABSTRACT FROM AUTHOR]

Cough is a powerful, protective expulsive behavior that assists in maintaining respiratory health by clearing foreign material, pathogens, and mucus from the airways. Therefore, cough is critical to survival in both health and disease. Importantly, cough protects the airways and lungs from both antegrade (e.g., food, liquid, saliva) and retrograde (e.g., bile, gastric acid) aspirate contents. Aspiration is often the result of impaired swallowing (dysphagia), which allows oral and/or gastric contents to enter the lung, especially in individuals who also have cough dysfunction (dystussia). Cough hyposensitivity, downregulation, or desensitization- collectively referred to as hypotussia- is common in individuals with dysphagia, and increases the likelihood that aspirated material will reach the lung. The consequence of hypotussia with reduced airway clearance can include respiratory tract infection, chronic inflammation, and long-term damage to the lung parenchyma. Despite the clear implications for health, the problem of managing hypotussia in individuals with dysphagia is frequently overlooked. Here, we provide an overview of the current interventions and treatment approaches for hypotussic cough. We synthesize the available literature to summarize research findings that advance our understanding of these interventions, as well as current gaps in knowledge. Further, we highlight pragmatic resources to increase awareness of hypotussic cough interventions and provide support for the clinical implementation of evidence-based treatments. In culmination, we discuss potential innovations and future directions for hypotussic cough research. [ABSTRACT FROM AUTHOR]