Screening for optimal parameters for modified pharyngeal electrical stimulation for the treatment of dysphagia after stroke in rats.

Pharyngeal electrical stimulation (PES), a novel noninvasive peripheral nerve stimulation technique, can effectively improve neurogenic dysphagia and increase the safety and effectiveness of swallowing in the clinic. However, the lack of animal models for dysphagia has limited the mechanistic research on PES, which affects its wide application. Therefore, determining optimal parameters for PES in rats is needed to enable mechanistic studies. Modified PES (mPES), which has different waves and pulse widths from PES, was used; in previous studies mPES was found to have a neurological mechanism like that of PES. A poststroke dysphagia (PSD) model was established, and rats with dysphagia were grouped into three different intensities (0.1 mA, 0.5 mA, and 1 mA) for the selection of optimal intensity and three different frequencies (1 Hz, 2 Hz, and 5 Hz) for the selection of optimal frequency based on a stimulation duration of 10 min in the clinic. A Videofluroscopic Swallow Screen (VFSS) was used to assess swallowing function in rats before and after mPES treatment. The results showed that the 1 mA group had better swallowing function (p < 0.05) than the model group. Compared with the model group, the 1 Hz and 5 Hz groups had the same improvement in swallowing function (p < 0.05). However, the increase in excitatory signals in the sensorimotor cortex was more pronounced in the 5 Hz group than in the other frequency stimulation groups (p < 0.05). Combining the clinical findings with the above results, we concluded that the optimal stimulation parameter for mPES in rats is "frequency: 5 Hz, current intensity: 1 mA for 10 min/day", which provides a basis for future basic experimental studies of mPES in animals.

The effects of simulated gastroesophageal reflux on infant pig oropharyngeal feeding physiology.

The neural connectivity among the oral cavity, pharynx, and esophagus is a critical component of infant feeding physiology. Central integration of oral and pharyngeal afferents alters motor outputs to structures that power swallowing, but the potential effects of esophageal afferents on preesophageal feeding physiology are unclear. These effects may explain the prevalence of oropharyngeal dysphagia in infants suffering from gastroesophageal reflux (GER), though the mechanism underlying this relationship remains unknown. Here we use the validated infant pig model to assess the impacts of simulated GER on preesophageal feeding parameters. We used high-speed videofluoroscopy and electromyography to record bottle-feeding before and following the infusion of a capsaicin-containing solution into the lower esophagus. Sucking parameters were minimally affected by capsaicin exposure, such that genioglossus activity was unchanged and tongue kinematics were largely unaffected. Aspects of the pharyngeal swallow were altered with simulated GER, including increased thyrohyoid muscle activity, increased excursions of the hyoid and thyroid per swallow, decreased swallow frequency, and increased bolus sizes. These results suggest that esophageal afferents can elicit changes in pharyngeal swallowing. In addition, decreased swallowing frequency may be the mechanism by which esophageal pathologies induce oropharyngeal dysphagia. Although recent work indicates that oral or pharyngeal capsaicin may improve dysphagia symptoms, the decreased performance following esophageal capsaicin exposure highlights the importance of designing sensory interventions based upon neurophysiology and the mechanisms underlying disordered feeding. This mechanistic approach requires comprehensive data collection across the entirety of the feeding process, which can be achieved using models such as the infant pig.NEW & NOTEWORTHY Simulated gastroesophageal reflux (GER) in an infant pig model resulted in significant changes in pharyngeal swallowing, which suggests that esophageal afferents are centrally integrated to alter motor outputs to the pharynx. In addition, decreased swallow frequency and increased bolus sizes may be underlying mechanisms by which esophageal pathologies induce oropharyngeal dysphagia. The infant pig model used here allows for a mechanistic approach, which can facilitate the design of intervention strategies based on neurophysiology.

Oral and Pharyngeal Dysphagia in Adults.

Patients with oral and pharyngeal dysphagia have difficulty forming a cohesive bolus and/or transferring food from the mouth into the pharynx and esophagus to initiate the involuntary swallowing process. This may be accompanied by nasopharyngeal regurgitation, aspiration, and a sensation of residual food remaining in the pharynx. Abnormalities affecting the upper esophageal sphincter, pharynx, larynx, or tongue, in isolation or combination, result in oropharyngeal dysphagia affecting either or both transit and airway protection. These issues can be addressed with a combination of management of the underlying systemic disease, with surgical intervention or with swallow therapy.

Association Between Soft Tissue Measures From Computed Tomography and Upper Airway Collapsibility on Drug-Induced Sleep Endoscopy.

OBJECTIVE: Positive airway pressure (PAP) titration during drug-induced sleep endoscopy (DISE) provides objective measures of upper airway collapsibility. While skeletal measurements relate to collapsibility measures on DISE, the influence of soft tissue dimensions on upper airway collapsibility is not known. We analyzed the relationship of measures of upper airway soft tissue volumes, specifically soft palate, pharyngeal lateral walls, and tongue, with metrics of collapsibility. STUDY DESIGN: Cross-sectional analysis from a prospective cohort. SETTING: Academic medical center. METHODS: Patients seeking PAP alternative therapies for obstructive sleep apnea (OSA) underwent standardized supine computed tomography (CT) acquisition and DISE protocols. The CT analysis primarily focused on soft tissue volumes and, secondarily, on airway and skeletal volumetric measures. DISE with PAP administration (DISE-PAP) enabled the determination of the pressure at which inspiratory airflow first commenced (pharyngeal critical pressure, PcritA) and the pressure at which inspiratory flow limitation was abolished (pharyngeal opening pressure, PhOP). Both unadjusted and adjusted correlation analyses were performed to understand the relationship between upper airway anatomy and either PcritA or PhOP. RESULTS: One hundred thirty-nine subjects completed both CT and DISE-PAP. On average, patients were male (70.5%), white (84.2%), middle-aged (56.6 ± 13.5 years), and overweight (29.6 ± 4.7 kg/m2), with moderate-severe apnea-hypopnea index (29.7 ± 21.3 events/h). Adjusted for age, sex, body mass index, and skeletal volumes, soft palate, and lateral pharyngeal wall volumes were not associated with PhOP or PcritA, but a larger tongue was associated with more positive PhOP (⍴ = 0.20, P = .02), and more positive PcritA (⍴ = 0.16, P = .07). Exploratory analyses revealed smaller minimum cross-sectional retropalatal area and intramandibular volume were also associated with increased collapsibility measures. CONCLUSION: After controlling for clinical factors and skeletal volume, greater tongue volume was associated with more severe collapsibility during DISE. These results, in concert with previous work, suggest that greater tongue volume in a smaller skeletal dimensions contribute to the severity of airway collapsibility, a key driver of OSA pathogenesis.

Adverse pregnancy outcomes and pharyngeal flow limitation during sleep: Nulliparous Pregnancy Outcomes Study Monitoring Mothers-to-be (nuMoM2b).

BACKGROUND: Pharyngeal flow limitation during pregnancy may be a risk factor for adverse pregnancy outcomes but was previously challenging to quantify. Our objective was to determine whether a novel objective measure of flow limitation identifies an increased risk of pre-eclampsia (primary outcome) and other adverse outcomes in a prospective cohort: Nulliparous Pregnancy Outcomes Study Monitoring Mothers-to-be (nuMoM2b). METHODS: Flow limitation severity scores (0%=fully obstructed, 100%=open airway), quantified from breath-by-breath airflow shape, were obtained from home sleep tests during early (6-15 weeks) and mid (22-31 weeks) pregnancy. Multivariable logistic regression quantified associations between flow limitation (median overnight severity, both time-points averaged) and pre-eclampsia, adjusting for maternal age, body mass index (BMI), race, ethnicity, chronic hypertension and flow limitation during wakefulness. Secondary outcomes were hypertensive disorders of pregnancy (HDP), gestational diabetes mellitus (GDM) and infant birthweight. RESULTS: Of 1939 participants with flow limitation data at both time-points (mean±sd age 27.0±5.4 years and BMI 27.7±6.1 kg·m-2), 5.8% developed pre-eclampsia, 12.7% developed HDP and 4.5% developed GDM. Greater flow limitation was associated with increased pre-eclampsia risk: adjusted OR 2.49 (95% CI 1.69-3.69) per 2sd increase in severity. Findings persisted in women without sleep apnoea (apnoea-hypopnoea index <5 events·h-1). Flow limitation was associated with HDP (OR 1.77 (95% CI 1.33-2.38)) and reduced infant birthweight (83.7 (95% CI 31.8-135.6) g), but not GDM. CONCLUSIONS: Greater flow limitation is associated with increased risk of pre-eclampsia, HDP and lower infant birthweight. Flow limitation may provide an early target for mitigating the consequences of sleep disordered breathing during pregnancy.

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.

Differences in velopharyngeal pressures during speech sound production in patients with unilateral cleft lip and palate (UCLP) and healthy individuals.

Background: During articulation the velopharynx needs to be opened and closed rapidly and a tight closure is needed. Based on the hypothesis that patients with cleft lip and palate (CLP) produce lower pressures in the velopharynx than healthy individuals, this study compared pressure profiles of the velopharyngeal closure during articulation of different sounds between healthy participants and patients with surgically closed unilateral CLP (UCLP) using high resolution manometry (HRM). Materials and methods: Ten healthy adult volunteers (group 1: 20-25.5 years) and ten patients with a non-syndromic surgically reconstructed UCLP (group 2: 19.1-26.9 years) were included in this study. Pressure profiles during the articulation of four sounds (/i:/, /s/, /ʃ/ and /n/) were measured by HRM. Maximum, minimum and average pressures, time intervals as well as detection of a previously described 3-phase-model were compared. Results: Both groups presented with similar pressure curves for each phoneme with regards to the phases described and pressure peaks, but differed in total pressures. An exception was noted for the sound /i:/, where a 3-phase-model could not be seen for most patients with UCLP. Differences in velopharynx pressures of 50% and more were found between the two groups. Maximum and average pressures in the production of the alveolar fricative reached statistical significance. Conclusions: It can be concluded that velopharyngeal pressures of patients with UCLP are not sufficient to eliminate nasal resonance or turbulence during articulation, especially for more complex sounds. These results support a general understanding of hypernasality during speech implying a (relative) velopharyngeal insufficiency.

Polysomnographic airflow shapes and site of collapse during drug-induced sleep endoscopy.

BACKGROUND: Differences in the pharyngeal site of collapse influence efficacy of non-continuous positive airway pressure therapies for obstructive sleep apnoea (OSA). Notably, complete concentric collapse at the level of the palate (CCCp) during drug-induced sleep endoscopy (DISE) is associated with reduced efficacy of hypoglossal nerve stimulation, but CCCp is currently not recognisable using polysomnography. Here we develop a means to estimate DISE-based site of collapse using overnight polysomnography. METHODS: 182 OSA patients provided DISE and polysomnography data. Six polysomnographic flow shape characteristics (mean during hypopnoeas) were identified as candidate predictors of CCCp (primary outcome variable, n=44/182), including inspiratory skewness and inspiratory scoopiness. Multivariable logistic regression combined the six characteristics to predict clear presence (n=22) versus absence (n=128) of CCCp (partial collapse and concurrent tongue base collapse excluded). Odds ratios for actual CCCp between predicted subgroups were quantified after cross-validation. Secondary analyses examined complete lateral wall, tongue base or epiglottis collapse. External validation was performed on a separate dataset (ntotal=466). RESULTS: CCCp was characterised by greater scoopiness (ß=1.5±0.6 per 2sd, multivariable estimate±se) and skewness (ß=11.4±2.4) compared with non-CCCp. The odds ratio for CCCp in predicted positive versus negative subgroups was 5.0 (95% CI 1.9-13.1). The same characteristics provided significant cross-validated prediction of lateral wall (OR 6.3, 95% CI 2.4-16.5), tongue base (OR 3.2, 95% CI 1.4-7.3) and epiglottis (OR 4.4, 95% CI 1.5-12.4) collapse. CCCp and lateral wall collapse shared similar characteristics (skewed, scoopy), diametrically opposed to tongue base and epiglottis collapse characteristics. External validation confirmed model prediction. CONCLUSIONS: The current study provides a means to recognise patients with likely CCCp or other DISE-based site of collapse categories using routine polysomnography. Since site of collapse influences therapeutic responses, polysomnographic airflow shape analysis could facilitate precision site-specific OSA interventions.

Relationship between Swallowing Pressure and Saliva Residue on Endoscopic Evaluation in Pharyngeal Dysphagia.

OBJECTIVE: In pharyngeal dysphagia, poor pharyngeal contraction and upper esophageal sphincter (UES) dysfunction result in post-swallow saliva residue (SR). This study aimed to clarify the relationship between swallowing pressure and SR in the valleculae and piriform sinuses on flexible endoscopic evaluation of swallowing (FEES). METHODS: Pharyngeal dysphagia patients with Wallenberg syndrome were included. Amounts of post-swallow SR in the valleculae and piriform sinuses were classified into four grades using SR scores based on FEES. The Hyodo score was also calculated to evaluate swallowing function. High-resolution manometric data in the nasopharyngeal, oropharyngeal, hypopharyngeal, oro-hypopharyngeal, and UES zones on swallowing were obtained for comparison with SR and Hyodo scores. RESULTS: Of the 31 recruited, data from 26 patients who successfully underwent FEES and manometry were analyzed. Vallecular SR scores were strongly negatively correlated with a maximum pressure of the oropharynx (r = -0.52, p = 0.006), distal contractile integrals (DCI) of the oropharynx (r = -0.52, p = 0.007), and DCI of the oro-hypopharynx (r = -0.55, p = 0.004). Hyodo scores for parameters 1 and 4 (corresponding to salivary pooling and pharyngeal clearance, respectively) were strongly negatively correlated with a maximum hypopharyngeal pressure (r = -0.57, p = 0.002) and strongly positively correlated with peristaltic velocity (r = 0.53, p = 0.007), respectively. SR scores and Hyodo scores related to SR were not correlated with pressure data of the UES. CONCLUSION: Manometric analysis of our SR scoring method using FEES revealed that a higher amount of SR in the valleculae, but not in the piriform sinuses, is associated with weaker pharyngeal pressure in pharyngeal dysphagia, especially at the oropharyngeal level. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:3519-3526, 2024.

Swallowing improvement surgeries.

PURPOSE: To discuss the different swallowing improvement surgeries that address one or more dysfunctional pharyngolaryngeal structures causing dysphagia. These surgeries reduce the risk of aspiration without sacrificing vocal function. METHODS: We searched the PubMed database and used Google Scholar search engine to find studies discussing the different swallowing improvement surgeries. A manual search of references in selected articles and reviews was done as well. No chronologic limitation was set for the studies; however, only articles written in English and Japanese were considered. Due to the nature of this article, no particular inclusion or exclusion criteria were set when searching for studies to be used as references; however, all relevant studies were reviewed and agreed upon by the authors for inclusion in this review article. RESULTS/DISCUSSION: Surgeries to improve swallowing function can be categorized into those that reinforce nasopharyngeal closure or pharyngeal contraction, improve laryngeal elevation or pharyngoesophageal segment opening, and those that improve vocal fold closure to protect the airway during swallowing. They are an effective alternative treatment that may significantly improve these patients' quality of life. Swallowing rehabilitation with the altered pharyngolaryngeal structures is required post-operatively to significantly improve patients' dysphagia. CONCLUSIONS: Surgeries to improve swallowing function address specific dysfunctional sites involved in the swallowing mechanism. Choosing the most appropriate surgery for each patient requires knowledge of the pathophysiology for their dysphagia and detailed pre-operative work-up.

Validation of the DIGEST-FEES as a Global Outcome Measure for Pharyngeal Dysphagia in Parkinson's Disease.

Flexible Endoscopic Evaluation of Swallowing (FEES) is one of two diagnostic gold standards for pharyngeal dysphagia in Parkinson's disease (PD), however, validated global outcome measures at the patient level are widely lacking. The Dynamic Imaging Grade of Swallowing Toxicity for Flexible Endoscopic Evaluation of Swallowing (DIGEST-FEES) represents such an outcome measure but has been validated primarily for head and neck cancer collectives. The objective of this study was, therefore, to investigate the validity of the DIGEST-FEES in patients with PD. Content validity was evaluated with a modified Delphi expert survey. Subsequently, 66 FEES videos in PD patients were scored with the DIGEST-FEES. Criterion validity was determined using Spearman's correlation coefficient between the DIGEST-FEES and the Penetration-Aspiration Scale (PAS), the Yale-Residue-Rating-Scale, the Functional-Oral-Intake-Scale (FOIS), and the swallowing-related Unified-Parkinson-Disease-Rating-Scale (UPDRS) items. Inter-rater reliability was determined using 10 randomly selected FEES-videos examined by a second rater. As a result, the overall DIGEST-FEES-rating exhibited significant correlations with the Yale-Valleculae-Residue-Scale (r = 0.84; p < 0.001), the Yale-Pyriform-Sinus-Residue-Scale (r = 0.70; p < 0.001), the FOIS (r = - 0.55, p < 0.001), and the UPDRS-Swallowing-Item-Score (r = 0.42, p < 0.001). Further, the DIGEST-FEES-safety subscore correlated with the PAS (r = 0.63, p < 0.001). Inter-rater reliability was high for the overall DIGEST-FEES rating (quadratic weighted kappa of 0.82). Therefore, DIGEST-FEES is a valid and reliable score to evaluate overall pharyngeal dysphagia severity in PD. Nevertheless, the modified Delphi survey identified domains where DIGEST-FEES may need to be specifically adapted to PD or neurological collectives in the future.

Pharyngeal Cavity Electrical Stimulation-Assisted Swallowing for Post-stroke Dysphagia: A Systematic Review and Meta-analysis of Randomized Controlled Studies.

Stroke is the leading cause of death and disability among adults. The incidence of stroke per 100, 000 patient-years was 2875. As many as 37% to 78% of patients with acute strokes suffer dysphagia. Dysphagia can easily lead to inhalation pneumonia, dehydration, malnutrition, and other serious complications, affecting the quality of life of stroke patients and increasing their mortality. Effective prevention and treatment of post-stroke dysphagia are of great significance to improving the prognosis and quality of life of patients. Some studies have shown that Pharyngeal cavity electrical stimulation-assisted swallowing (PCES-assisted swallowing) has a positive effect on patients with post-stroke dysphagia. This study will evaluate the effects of PCES-assisted swallowing on post-stroke dysphagia, including swallowing function, withdrawal rate of nasal feeding tubes, duration of hospitalization, and so on. Randomized controlled trials (RCTs) of PCES-assisted swallowing in the treatment of post-stroke dysphagia were searched in eight databases, including Cochrane Library, Embase, PubMed, Web of Science, Chinese Biomedical Literature Database, VIP Information Resource System, CNKI, and Wanfang Medical Science. The retrieval time was from the database establishment to June 2022. Rayyan was used to screen the retrieved literature risk of bias for included studies and was calculated using ROB2.0. The RevMan 5.3 software was used for the meta-analysis with the standard mean difference (SMD) and 95% confidence interval (CI). The model type was a random effect model, The risk ratio (RR) was used as the effect size for the two categorical variables. The swallowing function scores, withdrawal rate of nasal feeding tubes, and Length of stay (LOS) of the intervention and control groups were extracted, and the results of the meta-analysis were presented using a forest plot. Six studies from 2010 to 2018 with a total of 341 people were included in the meta-analysis. All studies reported quantitative outcome measures for the severity of dysphagia, and some reported the withdrawal rate of nasal feeding tubes, LOS, and penetration-aspiration-scale (PAS). The overall swallowing function of the PCES group was better than that of the control group (SMD = - 0.20, 95%CI - 0.38 to - 0.03, P = 0.02). In terms of the severity of dysphagia, there was a statistically significant difference in the Dysphagia Severity Rating scale (DSRS) between the Pharyngeal cavity electrical stimulation (PCES) group and the control group (SMD = - 0.24, 95%CI - 0.48 to 0, P = 0.05). The PCES group nasal feeding withdrawal rate of nasal feeding tubes was higher than the control group (RR = 2.88, 95% CI 1.15 to 7.26, P = 0.02). There was no significant difference in the LOS between the PCES group and the control group (SMD = - 0.19, 95%CI - 0.44 to 0.07, P = 0.15). This systematic review and meta-analysis provide reasonably reliable evidence that PCES-assisted swallowing can improve nasogastric feeding swallowing function and the withdrawal rate of nasal feeding tubes in patients with post-stroke dysphagia. However, the evidence for reducing oral feeding, aspiration, and length of hospitalization stay is lacking, and further studies are needed.

The effect of pharyngeal structures on the severity of obstructive sleep apnea.

BACKGROUND/OBJECTIVE: Obstructive sleep apnea (OSA) is characterized by complete or partial cessation of breathing during sleep. The tongue is suggested as a possible anatomical site causing airway obstruction. However, the role of other pharyngeal structures in the development of OSA remains unclear. We designed a study using both the apnea-hypopnea index (AHI) and the oxygen saturation measurements to assess the severity of OSA. We aimed to identify critical anatomical structures of the upper airway that correlate with the severity of OSA and to evaluate the utility of magnetic resonance imaging (MRI) markers to detect possible OSA in patients without overt symptoms. MATERIALS AND METHODS: The study included participants referred to the neurology outpatient clinic from the check-up unit. Participants were grouped as controls, mild, moderate, or severe OSA according to the AHI. A cranial MRI with a field of view (FOV) encompassing the upper airway structures was obtained from all participants. The areas of the tongue and the uvula were measured on the sagittal images by drawing the boundaries of the tissues manually. The posterior air space (PAS) area was evaluated from regions of interest in five parallel planes. RESULTS: Of 105 participants, 30 were controls, 27 had mild, 25 had moderate, and 23 had severe OSA. The moderate and severe OSA groups did not differ in oxygen saturation levels during sleep. Therefore, patients with moderate and severe OSA were combined into one group (moderate/severe OSA). The area of the tongue was significantly larger in the moderate/severe OSA group compared to the control group. Both the tongue and the uvula areas showed a significant positive correlation with the AHI. CONCLUSION: Our findings suggest that the tongue and uvula have prominent roles in the severity of OSAS. It may be useful to measure these structures with MRI to screen for at-risk individuals without overt OSA symptoms.

Alterations in Swallowing Six Weeks After Primary Anterior Cervical Discectomy and Fusion (ACDF).

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.

Practical multidisciplinary framework for the assessment and management of patients with unexplained chronic aerodigestive symptoms.

OBJECTIVE: Patients experiencing unexplained chronic throat symptoms (UCTS) are frequently referred to gastroenterology and otolaryngology outpatient departments for investigation. Often despite extensive investigations, an identifiable structural abnormality to account for the symptoms is not found. The objective of this article is to provide a concise appraisal of the evidence-base for current approaches to the assessment and management of UCTS, their clinical outcomes, and related healthcare utilisation. DESIGN: This multidisciplinary review critically examines the current understanding of aetiological theories and pathophysiological drivers in UCTS and summarises the evidence base underpinning various diagnostic and management approaches. RESULTS: The evidence gathered from the review suggests that single-specialty approaches to UCTS inadequately capture the substantial heterogeneity and pervasive overlaps among clinical features and biopsychosocial factors and suggests a more unified approach is needed. CONCLUSION: Drawing on contemporary insights from the gastrointestinal literature for disorders of gut-brain interaction, this article proposes a refreshed interdisciplinary approach characterised by a positive diagnosis framework and patient-centred therapeutic model. The overarching aim of this approach is to improve patient outcomes and foster collaborative research efforts.

Actualización sobre el síndrome de Eagle y sus complicaciones neurocardiológicas: casos clínicos / An update on Eagle´s syndrome and its neuro-cardiological complications: clinical cases

El síndrome de Eagle o síndrome estilohioideo o sín-drome de la arteria carótida es un trastorno que se origina por la mineralización y elongación del pro-ceso estiloides. Factores traumáticos agudos y cró-nicos, así como otras teorías, han sido propuestos para explicar la etiología y patogenia de esta altera-ción. El conjunto de síntomas puede incluir: dolor fa-ríngeo, odinofagia, disfagia, cefalea, con irradiación a oreja y zona cervical. Si bien existen varias clasifi-caciones, de manera universal se acepta que existen principalmente dos formas de presentación de esta patología: el tipo I o clásico, generalmente asociado a un trauma faríngeo y acompañado de dolor en la zona faríngea y cervical, y el tipo II o carotídeo, que sue-le presentar molestia cervical, cefalea y alteración de la presión arterial, con riesgo de daño de la ac-tividad cardíaca. La identificación de este síndrome suele ser confusa dada la similitud de los síntomas con otras afecciones. El diagnóstico debe realizarse en base a los síntomas y a los estudios por imágenes específicos. El tratamiento puede ser conservador y actuar simplemente sobre los síntomas, o bien, qui-rúrgico. El objetivo del presente trabajo es realizar una revisión actualizada de la literatura sobre el sín-drome de Eagle y presentar tres casos clínicos con distintas manifestaciones (AU)

Eagle's syndrome or styloid syndrome or stylo-carotid artery syndrome is a disease caused by mineralization and elongation of the styloid process. Acute and chronic traumatic factors, along with other hypothesis, have been proposed to explain the aetiology and pathogenesis of this condition. Symptoms can include: pharynx pain, odynophagia, dysphagia, headache, with radiating pain to the ear and neck. Despite there are several classifications, it is universally accepted that this pathology can present in two forms: the type I or classic, generally associated to tonsillar trauma and characterized by pharyngeal and neck pain, and the type II or carotid artery type, which frequently presents with neck pain, headache, blood pressure variation, with risk of damage to cardiac function. Identifying of Eagle's syndrome is often confusing because some symptoms are shared with other pathologies. Diagnosis must be made on the basis of symptoms and imaging studies. Treatment can be conservative, acting only on symptoms, or surgical. The aim of this paper is to provide an updated review of the literature on Eagle syndrome and to present three clinical cases with different manifestations (AU)

Management of pharyngeal collapse in patients affected by moderate obstructive sleep apnoea syndrome.

Objective: This study reports our experience in a selected cohort of patients affected by mild-moderate OSAS, without tonsillar obstruction, and treated with pharyngoplasty. Methods: In a case-control retrospective study, we compared modified expansion sphincter pharyngoplasty (MESP) to modified barbed reposition pharyngoplasty (MBRP) in adult patients with oropharyngeal transversal collapse with a BMI ≤ 30 kg/m2, and mild-moderate obstructive sleep apnoea syndrome (OSAS). A clinical evaluation, including collection of anthropometric data and sleep endoscopy, was performed. Six months after surgery, symptoms recording, clinical evaluation and polysomnography (PSG) were repeated. Results: We enrolled 20 patients: 10 treated with MESP and 10 treated with MBRP. Mean apnoea-hypoapnoea index (AHI) was 22.8 (± 5.63). We observed in both groups a significant reduction of AHI and oropharyngeal obstruction (p = 0.01), with a success rate, according with Sher's criteria, of 90% for MESP and 80% for MBRP, respectively. Post-surgical pain and snoring reduction were significantly lower with MBRP. Conclusions: We recorded similar success rates for both techniques. MBRP may be considered better than MESP due to less surgical time, no potential mucosal damage, absence of knots, and faster recovery with less pain.

Ventilatory Drive Withdrawal Rather Than Reduced Genioglossus Compensation as a Mechanism of Obstructive Sleep Apnea in REM Sleep.

Rationale: REM sleep is associated with reduced ventilation and greater obstructive sleep apnea (OSA) severity than non-REM (nREM) sleep for reasons that have not been fully elucidated. Objectives: Here, we use direct physiological measurements to determine whether the pharyngeal compromise in REM sleep OSA is most consistent with 1) withdrawal of neural ventilatory drive or 2) deficits in pharyngeal pathophysiology per se (i.e., increased collapsibility and decreased muscle responsiveness). Methods: Sixty-three participants with OSA completed sleep studies with gold standard measurements of ventilatory "drive" (calibrated intraesophageal diaphragm EMG), ventilation (oronasal "ventilation"), and genioglossus EMG activity. Drive withdrawal was assessed by examining these measurements at nadir drive (first decile of drive within a stage). Pharyngeal physiology was assessed by examining collapsibility (lowered ventilation at eupneic drive) and responsiveness (ventilation-drive slope). Mixed-model analysis compared REM sleep with nREM sleep; sensitivity analysis examined phasic REM sleep. Measurements and Main Results: REM sleep (⩾10 min) was obtained in 25 patients. Compared with drive in nREM sleep, drive in REM sleep dipped to markedly lower nadir values (first decile, estimate [95% confidence interval], -21.8% [-31.2% to -12.4%] of eupnea; P < 0.0001), with an accompanying reduction in ventilation (-25.8% [-31.8% to -19.8%] of eupnea; P < 0.0001). However, there was no effect of REM sleep on collapsibility (ventilation at eupneic drive), baseline genioglossus EMG activity, or responsiveness. REM sleep was associated with increased OSA severity (+10.1 [1.8 to 19.8] events/h), but this association was not present after adjusting for nadir drive (+4.3 [-4.2 to 14.6] events/h). Drive withdrawal was exacerbated in phasic REM sleep. Conclusions: In patients with OSA, the pharyngeal compromise characteristic of REM sleep appears to be predominantly explained by ventilatory drive withdrawal rather than by preferential decrements in muscle activity or responsiveness. Preventing drive withdrawal may be the leading target for REM sleep OSA.

Impaired Proximal Esophageal Contractility Predicts Pharyngeal Reflux in Patients With Laryngopharyngeal Reflux Symptoms.

OBJECTIVES: The pathophysiology of laryngopharyngeal reflux (LPR) remains incompletely understood. Proximal esophageal motor dysfunction may impair bolus clearance, increasing the risk of pharyngeal refluxate exposure. We aimed to evaluate the association of proximal esophageal contractility with objective reflux metrics. METHODS: We evaluated adults with LPR symptoms undergoing high-resolution manometry (HRM) and combined hypopharyngeal-esophageal multichannel intraluminal impedance-pH testing at a tertiary center between March 2018 and August 2019. Routine parameters per Chicago classification were obtained on HRM. Proximal esophageal contractility was evaluated using proximal contractile integral (PCI), which quantifies contractile pressure >20 mm Hg for the region spanning the distal margin of the upper esophageal sphincter and transition zone. Univariate (Kendall correlation and Student t test) and multivariable (general linear regression and logistic regression) analyses were performed. RESULTS: We enrolled 138 patients (66.7% women, mean age 57.1 years) in this study. Lower PCI was associated with an elevated risk of increased pharyngeal reflux (adjusted odds ratio 0.83 per 100 mm Hg-s-cm change in PCI, 95% confidence interval: 0.69-0.98), with a trend toward increased bolus exposure time and total reflux events, after multivariable adjustment. The relationship between PCI and pharyngeal reflux was strongest among participants without a primary motility disorder on HRM (adjusted odds ratio 0.63, 95% confidence interval: 0.42-0.85, P interaction = 0.04). Among continuously expressed reflux parameters, lower PCI was significantly associated with more distal acid reflux events (ß = -0.0094, P = 0.03) and total reflux events (ß = -0.0172, P = 0.05), after adjusting for confounders. DISCUSSION: Reduced proximal esophageal contractility as assessed by decreased PCI on HRM independently predicted increased pharyngeal reflux in patients with LPR symptoms, particularly among those without a coexisting motility disorder.

A preoperative predictive study of advantages of airway changes after maxillomandibular advancement surgery using computational fluid dynamics analysis.

The purpose of this study was to develop a simulation approach for predicting maxillomandibular advancement-induced airway changes using computational fluid dynamics. Eight patients with jaw deformities who underwent maxillomandibular advancement and genioglossus advancement surgery were included in this study. Computed tomography scans and rhinomanometric readings were performed both preoperatively and postoperatively. Computational fluid dynamics models were created, and airflow simulations were performed using computational fluid dynamics software; the preferable number of computational mesh points was at least 10 million cells. The results for the right and left nares, including simulation and postoperative measurements, were qualitatively consistent, and surgery reduced airflow pressure loss. Geometry prediction simulation results were qualitatively consistent with the postoperative stereolithography data and postoperative simulation results. Simulations were performed with either the right or left naris blocked, and the predicted values were similar to those found clinically. In addition, geometry prediction simulation results were qualitatively consistent with the postoperative stereolithography data and postoperative simulation results. These findings suggest that geometry prediction simulation facilitates the preoperative prediction of the postoperative structural outcome.