A dysphagia model with denervation of the pharyngeal constrictor muscles in guinea pigs: functional evaluation of swallowing.

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.

Social anxiety disorder in adolescents who stutter: A risk for school refusal.

Background: Stuttering is a childhood-onset fluency disorder. Part of the counseling for middle and high school students with persistent stuttering is related to school refusal. Anxiety disorders are known to contribute to school refusal.

Sustained Effects of Capsaicin Infusion into the Oropharynx on Swallowing in Perfused Rats.

Objectives: To examine the sustained effects of oropharyngeal capsaicin stimulation on the regulation of swallowing, we recorded the swallowing-related nerve activities during continuous infusion of capsaicin solution into the oropharynx.

Methods: In 33 in situ perfused brainstem preparation of rats, we recorded the activities of the vagus, hypoglossal, and phrenic nerves during fictive swallowing. The interburst intervals (IBIs) of the swallowing-related nerves during sequential pharyngeal swallowing (sPSW) elicited by electrical stimulation of the superior laryngeal nerve (SLN) during concurrent capsaicin stimulation of 10, 1, and 0.

Type I Thyroplasty Is Safe in Patients Undergoing Antithrombotic Therapy.

Introduction: Type I thyroplasty is one of the most useful surgeries for unilateral vocal fold paralysis. The study objective was to determine whether type I thyroplasty is safe and perioperative antithrombotic management is acceptable in patients undergoing antithrombotic therapy.

Methods: This is a single-hospital retrospective cohort study.

Effect of pharmacological inhibition of the pontine respiratory group on swallowing interneurons in the dorsal medulla oblongata.

Objectives: To examine the role of neurons of the pontine respiratory group (PRG) overlapping with the Kölliker-Fuse nucleus in the regulation of swallowing, we compared the activity of swallowing motor activities and interneuron discharge in the dorsal swallowing group in the medulla before and after pharmacological inhibition of the PRG.

Methods: In 23 in situ perfused brainstem preparation of rats, we recorded the activities of the vagus (VNA), hypoglossal (HNA), and phrenic nerves (PNA), and swallowing interneurons of the dorsal medulla during fictive swallowing elicited by electrical stimulation of the superior laryngeal nerve or oral water injection. Subsequently, respiratory- and swallow-related motor activities and single unit cell discharge were assessed before and after local microinjection of the GABA-receptor agonist muscimol into the area of PRG ipsilateral to the recording sites of swallowing interneurons.

Firing characteristics of swallowing interneurons in the dorsal medulla during physiologically induced swallowing in perfused brainstem preparation in rats.

Oropharyngeal swallowing is centrally mediated by a swallowing central pattern generator (Sw-CPG) in the medulla oblongata. The activity of the Sw-CPG depends on the sensory inputs determined by physical and chemical bolus properties. Here we investigate the sensory-motor integration during swallowing arising from different sensory sources.

Tracheoesophageal Diversion and Puncture for Preserving Phonation in Intractable Aspiration: A Case Series.

Objective/hypothesis: Tracheoesophageal diversion (TED) can prevent damage to the respiratory system in patients with swallowing disorders and/or repetitive aspiration pneumonia; however, TED may cause the loss of phonation. Our previous study demonstrated that TED with tracheoesophageal puncture (TEP) prevents aspiration while retaining phonation. In this study, we aimed to further evaluate the feeding status and phonation of patients who underwent TED with TEP to verify the reproducibility of this procedure.

Influences of GABAergic Inhibition in the Dorsal Medulla on Contralateral Swallowing Neurons in Rats.

Objectives: We aimed to examine the effect of unilateral inhibition of the medullary dorsal swallowing networks on the activities of swallowing-related cranial motor nerves and swallowing interneurons.

Methods: In 25 juvenile rats, we recorded bilateral vagal nerve activity (VNA) as well as unilateral phrenic and hypoglossal activity (HNA) during fictive swallowing elicited by electrical stimulation of the superior laryngeal nerve during control and following microinjection of the GABA agonist muscimol into the caudal dorsal medulla oblongata in a perfused brainstem preparation. In 20 animals, swallowing interneurons contralateral to the muscimol injection side were simultaneously recorded extracellularly and their firing rates were analyzed during swallowing.

Society of swallowing and dysphagia of Japan: Position statement on dysphagia management during the COVID-19 outbreak.

On April 14, the Society of Swallowing and Dysphagia of Japan (SSDJ) proposed its position statement on dysphagia treatment considering the ongoing spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The main routes of transmission of SARS-CoV-2 are physical contact with infected persons and exposure to respiratory droplets. In cases of infection, the nasal cavity and nasopharynx have the highest viral load in the body.

Intracellular activity of pharyngeal motoneurons during breathing, swallowing, and coughing.

We recorded membrane potentialp changes in 45 pharyngeal motoneurons (PMs) including 33 expiratory modulated and 12 nonrespiratory neurons during breathing, swallowing, and coughing in decerebrate paralyzed cats. Four types of membrane potential changes were observed during swallowing: ) depolarization during swallowing ( = 27), ) depolarization preceded by a brief (≤ 0.1 s) hyperpolarization ( = 4), ) longer term (> 0.

Awareness of stuttering in Japanese children aged 3-7 years.

Background: Boey et al. (2009) devised a questionnaire for measuring children's awareness of stuttering and showed that even very young children were often aware of their stuttering. There has been no replication of studies using Boey et al.

Tracheoesophageal diversion improves oral uptake of food: a retrospective study.

Purpose: Tracheoesophageal diversion (TED) is an effective therapeutic procedure for intractable aspiration. In this study, we performed TED in cases of intractable aspiration and/or repetitive pneumonia, investigated the main route of nutritional uptake after the procedure, and evaluated the swallowing method using videofluoroscopy. We also evaluated the validity of TED for treating intractable aspiration.

Laryngeal afferent modulation of swallowing interneurons in the dorsal medulla in perfused rats.

Objectives: The purpose of this study was to investigate the influence of laryngeal afferent inputs on brainstem circuits that mediate and transmit swallowing activity to the orofacial musculature.

Methods: Experiments were performed on 19 arterially perfused juvenile rats. The activities of swallowing interneurons in relation to their respective motor outputs in the hypoglossal and vagus nerves were assessed during fictive swallowing with or without concurrent laryngeal sensory stimulation at intensities of 20, 40, and 60 μA.

Sarcopenia and dysphagia: Position paper by four professional organizations.

This report was written by the Japanese Society of Dysphagia Rehabilitation, the Japanese Association of Rehabilitation Nutrition, the Japanese Association on Sarcopenia and Frailty, and the Society of Swallowing and Dysphagia of Japan to consolidate the currently available evidence on the topics of sarcopenia and dysphagia. Histologically, the swallowing muscles are of different embryological origin from somatic muscles, and receive constant input stimulation from the respiratory center. Although the swallowing muscles are striated, their characteristics are different from those of skeletal muscles.

Activity of swallowing-related neurons in the medulla in the perfused brainstem preparation in rats.

Objectives/hypothesis: We aimed to investigate and validate the cellular activity patterns and the potential topographical organization of neurons of the medullary swallowing pattern generator (Sw-CPG). We used the perfused brainstem preparation as an innovative experimental model that allows for stable neuronal recording in the brainstem.

Study Design: Animal model.

Supportive effect of interferential current stimulation on susceptibility of swallowing in guinea pigs.

Sensory-motor control of the pharyngeal swallow requires sensory afferent inputs from the pharynx and larynx evoked by introducing bolus into the pharynx. Patients with reduced sensitivity of the pharynx and larynx are likely to have a swallowing impairment, such as pre-swallow aspiration due to delayed swallow triggering. Interferential current stimulation applied to the neck is thought to improve the swallowing function of dysphagic patients, although the mechanism underlying the facilitatory effect of such stimulation remains unknown.

A case of multiple system atrophy-parkinsonian type with stuttering- and palilalia-like dysfluencies and putaminal atrophy.

Both developmental and acquired stuttering are related to the function of the basal ganglia-thalamocortical loop, which includes the putamen. Here, we present a case of stuttering- and palilalia-like dysfluencies that manifested as an early symptom of multiple system atrophy-parkinsonian type (MSA-P) and bilateral atrophy of the putamen. The patient was a 72-year-old man with no history of developmental stuttering who presented with a stutter for consultation with our otorhinolaryngology department.

Videoendoscopy worsens swallowing function: a videofluoroscopic study. A randomized controlled trial.

Aspiration pneumonia is a cause of mortality in the elderly. Evaluating swallowing function is important. Videofluoroscopy and flexible endoscopic evaluation of swallowing are comparable; however, observing all swallowing dynamics is impossible using the latter approach.

Abnormal auditory synchronization in stuttering: A magnetoencephalographic study.

In a previous magnetoencephalographic study, we showed both functional and structural reorganization of the right auditory cortex and impaired left auditory cortex function in people who stutter (PWS). In the present work, we reevaluated the same dataset to further investigate how the right and left auditory cortices interact to compensate for stuttering. We evaluated bilateral N100m latencies as well as indices of local and inter-hemispheric phase synchronization of the auditory cortices.

Long-term outcomes of type I thyroplasty with silicone implantation: Assessment of excised laryngeal tissue from a patient with secondary hypopharyngeal carcinoma.

Here we describe the long-term outcomes of type I thyroplasty (TP-I) with silicone block implantation through histopathological assessments in a male patient who underwent pharyngolaryngectomy for secondary hypopharyngeal carcinoma 7 years after silicone implantation. A 66-year-old man presented with esophageal carcinoma and underwent subtotal esophagotomy. Subsequently, his left vocal fold exhibited fixation in a paramedian position, and he underwent TP-I with silicone block implantation 2 years after the primary esophageal surgery.

Tracheobronchomegaly associated with laryngo-tracheal amyloidosis: First case report.

Tracheobronchomegaly (TBM) is a rare enlargement of the tracheal cartilage, also known as Mounier-Kuhn syndrome (MKS). Here, we describe an unusual case of acquired TBM in an adult, caused by amyloid regeneration and associated tracheal weakening, rather than by MKS. CT scan and fiberscopic examination of a 55-year-old woman suffering from severe dyspnea revealed TBM and subglottic stenosis, which was caused by deposition of amyloid tissue.

Spontaneous improvement of laryngeal sarcoidosis resistant to systemic corticosteroid administration.

We report herein a case of laryngeal sarcoidosis that was refractory to systemic corticosteroids, but that improved spontaneously. A 49-year-old woman complained of dysphagia and hoarseness with accompanying edematous swellings of both arytenoid regions. She was referred to our hospital after systemic corticosteroid therapy failed to achieve any improvement.

Role of the retrotrapezoid nucleus/parafacial respiratory group in coughing and swallowing in guinea pigs.

The retrotrapezoid/parafacial respiratory group (RTN/pFRG) located ventral to the facial nucleus plays a key role in regulating breathing, especially enhanced expiratory activity during hypercapnic conditions. To clarify the roles of the RTN/pFRG region in evoking coughing, during which reflexive enhanced expiration is produced, and in swallowing, during which the expiratory activity is consistently halted, we recorded extracellular activity from RTN/pFRG neurons during these fictive behaviors in decerebrate, paralyzed, and artificially ventilated guinea pigs. The activity of the majority of recorded respiratory neurons was changed in synchrony with coughing and swallowing.

Activity of respiratory neurons in the rostral medulla during vocalization, swallowing, and coughing in guinea pigs.

To examine the relationship between the neuronal networks underlying respiration and non-respiratory behaviors such as vocalization and airway defensive reflexes, we compared the activity of respiratory neurons in the ventrolateral medulla during breathing with that during non-respiratory behaviors including vocalization, swallowing, and coughing in guinea pigs. During fictive vocalization the activity of augmenting expiratory neurons ceased, whereas the other types of expiratory neurons did not show a consistent tendency of increasing or decreasing activity. All inspiratory neurons discharged in synchrony with the phrenic nerve activity.