sEMG-based automatic characterization of swallowed materials.

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 R2 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 R2 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.

Screening of aspiration pneumonia using the modified Mallampati classification tool in older adults.

Pneumonia is a major cause of morbidity and mortality in older adults. In the aging society, screening methods for predicting aspiration pneumonia are crucial for its prevention. Changes in the oropharyngeal morphology and hyoid bone position may increase the risk of aspiration pneumonia. This multicenter study aimed to investigate a simple and effective screening method for predicting dysphagia and aspiration pneumonia. Overall, 191 older adults (aged 65 years or older) were randomly sampled using the simple random sampling technique. Oropharyngeal morphology was assessed using the modified Mallampati classification, which reflects the size of the tongue in the oropharyngeal cavity. The hyoid position was measured as the distance between the menton and laryngeal prominence to evaluate aging-related changes in the muscles of the laryngopharynx. Dysphagia was assessed using the repetitive saliva swallowing test (RSST), which measures the number of swallowing movements in 30 seconds; dysphasia is defined as less than 3 swallowing movements in 30 seconds. The aspiration signs were assessed based on history of choking or coughing reflex during eating or drinking and medical history of pneumonia. The study findings revealed that the modified Mallampati classification was significantly correlated with a medical history of pneumonia. A higher incidence of pneumonia was evident in the lower Mallampati classification, which shows the smaller size of the tongue base in the oropharyngeal cavity. The results of this study suggest that the modified Mallampati classification may be a possible screening method to predict the occurrence of pneumonia.

Novel Approach Combining Shallow Learning and Ensemble Learning for the Automated Detection of Swallowing Sounds in a Clinical Database.

Cervical auscultation is a simple, noninvasive method for diagnosing dysphagia, although the reliability of the method largely depends on the subjectivity and experience of the evaluator. Recently developed methods for the automatic detection of swallowing sounds facilitate a rough automatic diagnosis of dysphagia, although a reliable method of detection specialized in the peculiar feature patterns of swallowing sounds in actual clinical conditions has not been established. We investigated a novel approach for automatically detecting swallowing sounds by a method wherein basic statistics and dynamic features were extracted based on acoustic features: Mel Frequency Cepstral Coefficients and Mel Frequency Magnitude Coefficients, and an ensemble learning model combining Support Vector Machine and Multi-Layer Perceptron were applied. The evaluation of the effectiveness of the proposed method, based on a swallowing-sounds database synchronized to a video fluorographic swallowing study compiled from 74 advanced-age patients with dysphagia, demonstrated an outstanding performance. It achieved an F1-micro average of approximately 0.92 and an accuracy of 95.20%. The method, proven effective in the current clinical recording database, suggests a significant advancement in the objectivity of cervical auscultation. However, validating its efficacy in other databases is crucial for confirming its broad applicability and potential impact.

Effects of effortful swallowing against kinesiology taping resistance on the swallowing function in patients with poststroke dysphagia: A randomized controlled trial.

BACKGROUND: A dysphagia rehabilitation method using kinesiology taping (KT) was recently introduced, and its potential for clinical efficacy was demonstrated by evaluating muscle activity and thickness. However, its effect on the swallowing function in patients with dysphagia remains unclear. This study aimed to investigate the effects of effortful swallowing against KT resistance on the swallowing function in patients with post stroke dysphagia. METHODS: Thirty patients with poststroke dysphagia were recruited and randomly assigned to the experimental and placebo groups. In the experimental group, the KT was attached to the front of the neck (the hyoid bone between the sternum) with a tension of approximately 70% to 80%, and effortful swallowing was performed against the KT tension. In contrast, the placebo group performed effortful swallowing with KT applied at the same location without tension. The intervention was performed 30 times/day, 5 days/week for 6 weeks. The videofluoroscopic dysphagia scale (VDS) and penetration-aspiration scale (PAS) based on a videofluoroscopic swallowing study were used to analyze oropharyngeal swallowing function. RESULTS: The experimental group showed statistically significant improvements in the oral and pharyngeal phases of the VDS (P = .029 and .007, respectively) and PAS (P = .034) compared with the placebo group. Effect sizes were observed for the oral (0.3) and pharyngeal phases (0.5) of the VDS and PAS (1.1). CONCLUSION: This study demonstrated that effortful swallowing against resistance to KT is an effective therapeutic exercise for improving the swallowing function in patients with poststroke dysphagia.

Oropharyngeal swallowing hydrodynamics of thin and mildly thick liquids in an anatomically accurate throat-epiglottis model.

Understanding the mechanisms underlying dysphagia is crucial in devising effective, etiology-centered interventions. However, current clinical assessment and treatment of dysphagia are still more symptom-focused due to our limited understanding of the sophisticated symptom-etiology associations causing swallowing disorders. This study aimed to elucidate the mechanisms giving rise to penetration flows into the laryngeal vestibule that results in aspirations with varying symptoms. Methods: Anatomically accurate, transparent throat models were prepared with a 45° down flapped epiglottis to simulate the instant of laryngeal closure during swallowing. Fluid bolus dynamics were visualized with fluorescent dye from lateral, rear, front, and endoscopic directions to capture key hydrodynamic features leading to aspiration. Three influencing factors, fluid consistency, liquid dispensing site, and dispensing speed, were systemically evaluated on their roles in liquid aspirations. Results: Three aspiration mechanisms were identified, with liquid bolus entering the airway through (a) the interarytenoid notch (notch overflow), (b) cuneiform tubercle recesses (recess overflow), and (c) off-edge flow underneath the epiglottis (off-edge capillary flow). Of the three factors considered, liquid viscosity has the most significant impact on aspiration rate, followed by the liquid dispensing site and the dispensing speed. Water had one order of magnitude higher aspiration risks than 1% w/v methyl cellulose solution, a mildly thick liquid. Anterior dispensing had higher chances for aspiration than posterior oropharyngeal dispensing for both liquids and dispensing speeds considered. The effects of dispending speed varied. A lower speed increased aspiration for anterior-dispensed liquids due to increased off-edge capillary flows, while it significantly reduced aspiration for posterior-dispensed liquids due to reduced notch overflows. Visualizing swallowing hydrodynamics from multiple orientations facilitates detailed site-specific inspections of aspiration mechanisms.

In-depth analysis of pre- and postoperative functional outcome parameters in patients receiving laryngotracheal surgery.

OBJECTIVES: Surgical treatment for airway stenosis necessitates personalized techniques based on the stenosis location and length, leading to favourable surgical outcomes. However, there is limited literature on functional outcomes following laryngotracheal surgery with an adequate number of patients. METHODS: We conducted a retrospective analysis of patients who underwent laryngotracheal surgery at the Department of Thoracic Surgery, Medical University of Vienna, from January 2017 to June 2021. The study included standardized functional assessments before and after surgery, encompassing spirometry, voice measurements, swallowing evaluation and subjective patient perception. RESULTS: The study comprised 45 patients with an average age of 51.9 ± 15.9 years, of whom 89% were female, with idiopathic being the most common aetiology (67%). Procedures included standard cricotracheal resection in 11%, cricotracheal resection with dorsal mucosal flap in 49%, cricotracheal resection with dorsal mucosal flap and lateral cricoplasty in 24% and single-stage laryngotracheal reconstruction in 16%. There were no in-hospital mortalities or restenosis cases during the mean follow-up period of 20.8 ± 13.2 months. Swallowing function remained intact in all patients. Voice evaluations showed a decrease in fundamental vocal pitch [203 (81-290) Hz vs 150 (73-364) Hz, P < 0.001] and dynamic voice range (23.5 ± 5.8 semitones vs 17.8 ± 6.7 semitones, P < 0.001). However, no differences in voice volume were observed (60.0 ± 4.1 dB vs 60.2 ± 4.8 dB, P = 0.788). The overall predicted voice profile changed from R0B0H0 to R1B0H1. CONCLUSIONS: Laryngotracheal surgery proves effective in fully restoring breathing capacity while preserving vocal function. Even in cases of high-grade and complex airway stenosis necessitating laryngotracheal reconstruction, favourable functional outcomes can be achieved.

A comparison of swallowing related quality of life in patients undergoing transoral endoscopic versus open thyroid surgery.

INTRODUCTION: It is important for the endoscopic thyroid surgeon to understand the pros and cons of trans-oral endoscopic thyroidectomy-vestibular approach (TOETVA) vis-à-vis, open conventional thyroidectomy (OTx) so he/she can help patients in making informed choices regarding the type of procedure to opt for. Swallowing related quality of life (SWAL-QoL) has not been compared between the two approaches. Using a rigorous qualitative methodology and validated reliable tool, this study set out to compare the swallowing related quality of life in patients undergoing TOETVA versus OTx. METHODS: Prospective study at 3 time points in patients planned for hemithyroidectomy (Preoperative, 1 week and 12 weeks). Data were collected on patients at a tertiary teaching institute in India. Participants ranged from age 18-60 years with a diagnosis of benign euthyroid nodule undergoing hemithyroidectomy. Exclusion criteria were-(1) pre-existing vocal cord abnormalities, (2) undergoing surgery for recurrent nodules, and (3) any neuro-muscular disease affecting swallowing ability. Main outcome measure was comparison of swallowing related quality of life domain scores between patients undergoing hemithyroidectomy via either endoscopic trans-oral or open approach. RESULTS: Of the 82 included patients, 40 underwent TOETVA and 42 OTx. Both the groups were comparable in terms of demographic and clinicopathological profile. The mean preoperative SWAL-QOL scores were comparable in all domains. Mean SWAL-QoL scores for all domains on postoperative day 7 were significantly better in TOETVA group with domains burden, eating desire, mental health and communication having medium effect sizes. Physical symptom domain was better in the OTx group but had a small effect size. The difference in SWAL-QoL domains between the two groups persisted for 3 months also. CONCLUSION: Swallowing related quality of life after trans-oral endoscopic thyroidectomy compared to conventional open surgery has not been reported in the literature. Our findings suggest that trans-oral endoscopic thyroidectomy results in significant superior swallowing related quality of life in the majority of domains.

Scaling of buccal mass growth and muscle activation determine the duration of feeding behaviours in the marine mollusc Aplysia californica.

The mechanical forces experienced during movement and the time constants of muscle activation are important determinants of the durations of behaviours, which may both be affected by size-dependent scaling. The mechanics of slow movements in small animals are dominated by elastic forces and are thus quasistatic (i.e. always near mechanical equilibrium). Muscular forces producing movement and elastic forces resisting movement should scale identically (proportional to mass2/3), leaving the scaling of the time constant of muscle activation to play a critical role in determining behavioural duration. We tested this hypothesis by measuring the duration of feeding behaviours in the marine mollusc Aplysia californica whose body sizes spanned three orders of magnitude. The duration of muscle activation was determined by measuring the time it took for muscles to produce maximum force as A. californica attempted to feed on tethered inedible seaweed, which provided an in vivo approximation of an isometric contraction. The timing of muscle activation scaled with mass0.3. The total duration of biting behaviours scaled identically, with mass0.3, indicating a lack of additional mechanical effects. The duration of swallowing behaviour, however, exhibited a shallower scaling of mass0.17. We suggest that this was due to the allometric growth of the anterior retractor muscle during development, as measured by micro-computed tomography (micro-CT) scans of buccal masses. Consequently, larger A. californica did not need to activate their muscles as fully to produce equivalent forces. These results indicate that muscle activation may be an important determinant of the scaling of behavioural durations in quasistatic systems.

Incidence and characterization of aerophagia in dogs using videofluoroscopic swallow studies.

BACKGROUND: Aerophagia (ingestion of air), is a functional aerodigestive disorder in people. Criteria for diagnosis of aerophagia in dogs are >1/3 of bolus volume containing air or ingested air resulting in gastric distention (>1/3 of end gastric volume). Aerophagia is highlighted during eating and drinking. Videofluoroscopic swallow studies (VFSS) document aerophagia in dogs, but the incidence, clinical signs (CS), and associated disorders are unknown. OBJECTIVES: Identify the incidence of aerophagia, compare CS between dogs with and without aerophagia, and identify associated and predisposing disorders using VFSS. ANIMALS: A total of 120 client-owned dogs. METHODS: Sequential VFSS and associated medical records from dogs presenting to veterinary teaching hospitals at Auburn University and the University of Missouri were retrospectively reviewed. Statistical comparisons were made using Mann-Whitney and chi-squared tests, odds ratios (OR), and multiple logistic regression (P < .05). RESULTS: The incidence (95% confidence interval [CI]) of aerophagia was 40% (31.7-48.9). Dogs with mixed CS (gastrointestinal [GI] and respiratory; P < .001, 58.3%) were more likely to have aerophagia than dogs with exclusively respiratory CS (25%). Aerophagia was significantly more common in brachycephalic dogs (P = .01; 45.8% vs 13.8%), dogs with nonbrachycephalic upper airway obstruction (P < .001; 33.3% vs 4.1%), pathologic penetration and aspiration (P-A) scores (P = .04; 41.6% vs 23.6%), and gagging (P < .001; 25% vs 11.7%). Mixed CS (P = .01), brachycephaly (P < .001), and upper airway obstruction (P < .001) were independent predictors of aerophagia. CONCLUSIONS AND CLINICAL IMPORTANCE: Aerophagia was common, particularly in dogs with mixed CS. Brachycephalic dogs and dogs with upper airway obstruction are predisposed. Aspiration risk was high, emphasizing overlapping upper aerodigestive pathways.

Neurophysiological characterization of oropharyngeal dysphagia in older patients.

OBJECTIVE: To characterize swallowing biomechanics and neurophysiology in older patients with oropharyngeal dysphagia (OD). METHODS: Observational study in 12 young healthy volunteers (HV), 9 older HV (OHV) and 12 older patients with OD with no previous diseases causing OD (OOD). Swallowing biomechanics were measured by videofluoroscopy, neurophysiology with pharyngeal sensory (pSEP) and motor evoked-potentials (pMEP) to intrapharyngeal electrical and transcranial magnetic stimulation (TMS), respectively, and salivary neuropeptides with enzyme-linked immunosorbent assay (ELISA). RESULTS: 83.3% of OOD patients had unsafe swallows (Penetration-Aspiration scale = 4.3 ± 2.1; p < 0.0001) with delayed time to laryngeal vestibule closure (362.5 ± 73.3 ms; p < 0.0001) compared to both HV groups. OOD patients had: (a) higher pharyngeal sensory threshold (p = 0.009) and delayed pSEP P1 and N2 latencies (p < 0.05 vs HV) to electrical stimulus; and (b) higher pharyngeal motor thresholds to TMS in both hemispheres (p < 0.05) and delayed pMEPs latencies (right, p < 0.0001 HV vs OHV/OOD; left, p < 0.0001 HV vs OHV/OOD). CONCLUSIONS: OOD patients have unsafe swallow and delayed swallowing biomechanics, pharyngeal hypoesthesia with disrupted conduction of pharyngeal sensory inputs, and reduced excitability and delayed cortical motor response. SIGNIFICANCE: These findings suggest new elements in the pathophysiology of aging-associated OD and herald new and more specific neurorehabilitation treatments for these patients.

Relationship between endoscopic gastroesophageal valve grading and mean nocturnal baseline impedance and postreflux swallow-induced peristaltic wave index in patients with gastroesophageal reflux disease.

This study aimed to investigate the relationship between endoscopic gastroesophageal valve grading and mean nocturnal baseline impedance (MNBI) and postreflux swallow-induced peristaltic wave index (PSPWI) in patients with gastroesophageal reflux disease (GERD). A total of 120 patients diagnosed with GERD disease were included in the study. According to the classification of endoscopic gastroesophageal valves, the patients were divided into 5 groups, group 1 as baseline group, and Group 2-4 as Hill grade I-IV. Basic information about the patients was collected, including age and gender. The mean nocturnal baseline impedance and creep wave index induced by swallowing after rumination were measured by high resolution creep measurement technique. Through statistical analysis, the relationship between valve classification and observation index was discussed. In terms of MNBI, impedance values gradually decreased with increasing valve classification. The average impedance of the Grade 1 group was 23.5 mm Hg/cm2, while the average impedance of the Grade 5 group was 15.2 mm Hg/cm2. This reduction showed a significant decreasing trend (P < .001). In addition, in terms of the peristaltic wave index caused by swallowing after regurgitation, the peristaltic wave index gradually increased with the increase of valve classification. The mean index in the Grade 1 group was 1.8 beats/min, while the mean index in the Grade 5 group was 3.6 beats/min. This increase showed a significant positive relationship (P < .001). Endoscopic gastroesophageal valve grading was significantly correlated with MNBI and PSPWI in patients with GERD. These observations can serve as useful tools for assessing the severity of GERD and monitoring disease progression.

Extrinsic Laryngeal Muscle Activity With Different Diameters and Water Depths in a Semi-Occluded Vocal Tract Exercise.

PURPOSE: Surface electromyography (sEMG) has been used to evaluate extrinsic laryngeal muscle activity during swallowing and phonation. In the current study, sEMG amplitudes were measured from the infrahyoid and suprahyoid muscles during phonation through a tube submerged in water. METHOD: The sEMG amplitude values measured from the extrinsic laryngeal muscles and the electroglottographic contact quotient (CQ) were obtained simultaneously from 62 healthy participants (31 men, 31 women) during phonation through a tube at six different depths (2, 4, 7, 10, 15, and 20 cm) while using two tubes with different diameters (1 and 0.5 cm). RESULTS: With increasing depth, the sEMG amplitude for the suprahyoid muscles increased in men and women. However, sEMG amplitudes for the infrahyoid muscles increased significantly only in men. Tube diameter had a significant effect on the suprahyoid sEMG amplitudes only for men, with higher sEMG amplitudes when phonating with a 1.0-cm tube. CQ values increased with submerged depth for both men and women. Tube diameter affected results such than CQ values were higher for men when using the wider tube and for women with the narrower tube. CONCLUSIONS: Vocal fold vibratory patterns changed with the depth of tube submersion in water for both men and women, but the patterns of muscle activation differed between the sexes. This suggests that men and women use different strategies when confronted with increased intraoral pressure during semi-occluded vocal tract exercises. In this study, sEMG provided insight into the mechanism for differences between vocally normal individuals and could help detect compensatory muscle activation during tube phonation in water for people with voice disorders.

Chronic intermittent hypoxia reveals role of the Postinspiratory Complex in the mediation of normal swallow production.

Obstructive sleep apnea (OSA) is a prevalent sleep-related breathing disorder that results in multiple bouts of intermittent hypoxia. OSA has many neurological and systemic comorbidities, including dysphagia, or disordered swallow, and discoordination with breathing. However, the mechanism in which chronic intermittent hypoxia (CIH) causes dysphagia is unknown. Recently, we showed the postinspiratory complex (PiCo) acts as an interface between the swallow pattern generator (SPG) and the inspiratory rhythm generator, the preBötzinger complex, to regulate proper swallow-breathing coordination (Huff et al., 2023). PiCo is characterized by interneurons co-expressing transporters for glutamate (Vglut2) and acetylcholine (ChAT). Here we show that optogenetic stimulation of ChATcre:Ai32, Vglut2cre:Ai32, and ChATcre:Vglut2FlpO:ChR2 mice exposed to CIH does not alter swallow-breathing coordination, but unexpectedly disrupts swallow behavior via triggering variable swallow motor patterns. This suggests that glutamatergic-cholinergic neurons in PiCo are not only critical for the regulation of swallow-breathing coordination, but also play an important role in the modulation of swallow motor patterning. Our study also suggests that swallow disruption, as seen in OSA, involves central nervous mechanisms interfering with swallow motor patterning and laryngeal activation. These findings are crucial for understanding the mechanisms underlying dysphagia, both in OSA and other breathing and neurological disorders.

A randomized controlled study investigating the efficacy of electro-acupuncture and exercise-based swallowing rehabilitation for post-stroke dysphagia: Impacts on brainstem auditory evoked potentials and cerebral blood flow.

BACKGROUND: Swallowing rehabilitation behavioral therapy and traditional Chinese acupuncture therapy are widely used in the treatment of post-stroke dysphagia (PSD). This study investigated the therapeutic effect of electro-acupuncture combined with exercise-based swallowing rehabilitation on PSD and its effect on brainstem auditory evoked potential (BAEP) and cerebral blood flow. METHODS: The 120 PSD patients were divided into 2 groups (n = 60 each) by simple random grouping method, that is, an experimental and control group, receiving routine swallowing training, or additional intervention with electro-acupuncture at a frequency of 5 times/week. Data in swallowing function, BAEP, and cerebrovascular color Doppler ultrasound parameters were collected before treatment, as well as after treatment. An intergroup comparison was conducted using an independent sample t-test, and an intra-group comparison was conducted among different time points using a paired t-test. The data were analyzed using the SPSS Statistics 22.0 software; P < .05 was considered statistically significant. RESULTS: The therapeutic effects were significantly better in the experimental group compared with the control group (P < .05). The standard swallowing function assessment scores were significantly lower in both groups after treatment (P < .05), and the score in the observation group was lower than in the control group (P < .05). The peak latency of BAEP waves III and IV, and the inter-peak latency between peaks III to V and I to V in the 2 groups changed significantly (P < .05). The peak systolic velocity (PSV), end-diastolic velocity (EDV), and mean velocity (MV) were significantly increased in both groups after treatment (P < .05). The pulsatility index decreased significantly in both groups (P < .05), and the PSV, EDV, and MV were higher in the experimental group than in the control group (P < .05). CONCLUSION: Electro-acupuncture, combined with swallowing training in the treatment of Post-stroke Dysphagia, effectively improved cerebral microcirculation and conduction velocity, enhanced the motor function of swallowing muscles, and promoted the recovery of swallowing function.

Saliva Production and Esophageal Motility Influence Esophageal Acid Clearance Related to Post-reflux Swallow-Induced Peristaltic Wave.

BACKGROUND: The post-reflux swallow-induced peristaltic wave (PSPW) brings salivary bicarbonate to neutralize residual distal esophageal mucosal acidification. AIMS: To determine if reduced saliva production and esophageal body hypomotility would compromise PSPW-induced pH recovery in the distal esophagus. METHODS: In this multicenter retrospective cross-sectional study, patients with confirmed Sjogren's syndrome and scleroderma/mixed connective tissue disease (MCTD) who underwent high resolution manometry (HRM) and ambulatory pH-impedance monitoring off antisecretory therapy were retrospectively identified. Patients without these disorders undergoing HRM and pH-impedance monitoring for GERD symptoms were identified from the same time-period. Acid exposure time, numbers of reflux episodes and PSPW, pH recovery with PSPW, and HRM metrics were extracted. Univariate comparisons and multivariable analysis were performed to determine predictors of pH recovery with PSPW. RESULTS: Among Sjogren's syndrome (n = 34), scleroderma/MCTD (n = 14), and comparison patients with reflux symptoms (n = 96), the scleroderma/MCTD group had significantly higher AET, higher prevalence of hypomotility, lower detected reflux episodes, and very low numbers of PSPW (p ≤ 0.004 compared to other groups). There was no difference in pH-impedance metrics between Sjogren's syndrome, and comparison patients (p ≥ 0.481). Proportions with complete pH recovery with PSPW was lower in Sjogren's patients compared to comparison reflux patients (p = 0.009), predominantly in subsets with hypomotility (p < 0.001). On multivariable analysis, diagnosis of Sjogren's syndrome, scleroderma/MCTD or neither (p = 0.014) and esophageal hypomotility (p = 0.024) independently predicted lack of complete pH recovery with PSPW, while higher total reflux episodes trended (p = 0.051). CONCLUSIONS: Saliva production and motor function are both important in PSPW related pH recovery.

Do proprioceptive neuromuscular facilitation techniques improve respiratory parameters and swallowing in people with multiple sclerosis: A randomized-controlled study.

AIM: This study aims to investigate the effects of Proprioceptive Neuromuscular Facilitation (PNF) techniques on respiratory parameters, swallowing, functional capacity, fatigue, and quality of life in people with Multiple Sclerosis (PwMS). METHOD: Thirty-four PwMS were included and randomized into the PNF Group (mean age: 43.23±10.55/years) or Control Group (mean age:38.47±8.18/years). In the PNF group, head-neck, upper extremity, trunk, and breathing techniques were applied three days/eight weeks. The control group continued home-based breathing exercises. Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), FEV1/FVC, peak expiratory flow (PEF), forced expiratory flow 25-75 % (%FEF 25-75), peak cough flow (PCF), maximal inspiratory (MIP) and expiratory pressures (MEP) were and two minutes walking test (2MWT) were measured. Dysphagia in Multiple Sclerosis (DYMUS), Eating Assessment Tool (EAT-10), Fatigue Severity Scale (FSS) and Multiple Sclerosis Quality of Life (MusiQoL) were questioned. RESULTS: After treatment, MIP, MEP,%FEV1/FVCpred,%PEFpred,%FEF 25-75pred, PCF, DYMUS, EAT-10, FSS, and MUSIQoL were improved in the PNF group while MIP, MEP, PCF, DYMUS, EAT-10, MUSIQoL, and 2 MWT were improved in the control group (p < 0.05 for all). In the between-group analysis of the mean differences, the%FEV1pred was significantly different in favor of the PNF Group (p = 0.011), and MIP was significantly different in favor of the Control Group (p = 0.013). DISCUSSION: The PNF techniques can improve respiratory muscle strength, respiratory functions, cough efficiency, swallowing functions, and quality of life in mild to moderate PwMS. However, these improvements were not superior except for%FEV1pred compared to home-based breathing exercises.

Swallowing kinematics and submental muscles activation during a newly designed maneuver called Mouth Open Swallowing Maneuver: A comparative study.

The aim of this study was to design a new maneuver called the Mouth Open Swallowing Maneuver (MOSM), and to compare swallowing kinematics and submental muscles activation (SMA) between MOSM and two current approaches used in dysphagia rehabilitation. Fifty healthy volunteers were asked to perform three repetitions of dry swallowing (DS) (control task), the MOSM, the Mendelsohn Maneuver (MM), and the Tongue-Hold Maneuver (THM) during videofluoroscopic swallowing study accompanied with simultaneous SMA recording. Swallowing kinematics were measured by frame-by-frame analysis on hyolaryngeal movement using ImageJ. Swallowing with maximum hyolaryngeal movement and SMA during these tasks was used for comparative analysis. Vertical movement of the hyoid during the MOSM was significantly greater than those observed during the DS and the THM (p<0.001, p<0.001). Horizontal movement of the hyoid during DS and the THM was significantly greater than that observed during the MM (p = 0.001, p = 0.001). Vertical movement of the larynx during the MOSM was significantly greater than those observed during DS, MM, and THM (p<0.001). There was no significant difference between tasks in horizontal movement of the larynx (p = 0.785). SMA during the THM was significantly greater than that observed during MOSM (p = 0.002). No significant difference was found between other tasks in terms of SMA (p>0.05). The MOSM as a newly designed maneuver was significantly superior to other maneuvers in increasing vertical hyolaryngeal movement. The THM has as much effect on hyolaryngeal movement as the MM. In this study, the MOSM was shown to be effective in increasing hyolaryngeal movement. ClinicalTrials.gov Protocol Registration and Results System (PRS); the clinical trial registration number (NCT05579041).

Effect of high-frequency repetitive transcranial magnetic stimulation on swallowing function and pneumonia in poststroke dysphagia in rats.

BACKGROUND: Post-stroke dysphagia (PSD) is a common symptom of stroke. Clinical complications of PSD include malnutrition and pneumonia. Clinical studies have shown that high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) can improve the swallowing function in stroke patients. However, few studies have elucidated the underlying molecular mechanisms. METHODS: A PSD rat model was established using transient middle cerebral artery occlusion (tMCAO). Rats were randomly divided into sham-operated groups, PSD groups, PSD + sham-rTMS groups, PSD + 5 Hz-rTMS groups, PSD + 10 Hz-rTMS groups and PSD + 20 Hz-rTMS groups. Rats were weighed and videofluoroscopic swallowing studies were conducted. Pulmonary inflammation, levels of substance P (SP) and calcitonin gene-related peptide (CGRP) in the serum, lung, and nucleus tractus solitarius (NTS), brain-derived neurotrophic factor (BDNF) and 5-hydroxytryptamine (5HT) in NTS were evaluated. RESULTS: Rats in the PSD group experienced weight loss, reduced bolus area and pharyngeal bolus speed, and increased pharyngeal transit time (PTT) and inter-swallow interval (ISI) on day 7 and day 14 after operation. Moreover, PSD rats showed pulmonary inflammation, reduced levels of SP in the lung and serum, increased levels of CGRP in the lung and NTS, reduced levels of BDNF and 5HT in the NTS. There was no significant difference between the PSD group and the PSD + sham-rTMS group in the results of weight and VFSS. Comparing with the PSD group, there significant increases in the bolus area, decreases in PTT of rats following 5 Hz rTMS intervention. HF-rTMS at 10 Hz significantly increased the weight, bolus area, pharyngeal bolus speed and decreased the PTT and ISI of rats. There were also significant increases in the bolus area (p < 0.01) and pharyngeal bolus speed, decreases in PTT and ISI of rats following 20 Hz rTMS intervention. Furthermore, compared with the PSD + 5 Hz-rTMS group, there were significant increases in the bolus area and pharyngeal bolus speed, decreases in ISI in the swallowing function of rats in the PSD + 10 Hz-rTMS group. Besides, compared with the PSD + 5 Hz-rTMS group, there were significant decreases in ISI in the swallowing function of rats in the PSD + 20 Hz-rTMS group. HF-rTMS at 10 Hz alleviated pulmonary inflammation, increased the levels of SP in the lung, serum, and NTS, CGRP in the serum and NTS, 5HT in the NTS of PSD rats. CONCLUSION: Compared with 5 Hz and 20 Hz rTMS, 10 Hz rTMS more effectively improved the swallowing function of rats with PSD. HF-rTMS at 10 Hz improved the swallowing function and alleviated pneumonia in PSD rats. The mechanism may be related to increased levels of SP in the lung, serum and NTS, levels of CGRP in the serum and NTS, 5HT in the NTS after HF-rTMS treatment.