Pharyngeal High-resolution Manometry Research Articles

Characterization of pharyngeal contractile integral using pharyngeal manometry in children.

Pharyngeal contractile integral (PhCI) is the product of mean pharyngeal contractile amplitude, length, and duration, and provides a single metric for the vigor of entire pharyngeal contraction. A major limitation in children is lack of characterization of PhCI on high-resolution pharyngeal manometry. We aimed to determine and compare the values of PhCI in children with the abnormal and normal videofluoroscopic study of swallow (VFSS). Children who underwent high-resolution pharyngeal and esophageal manometry (HRPM/HREM), as well as VFSS, were divided into two groups; "normal VFSS" and "abnormal VFSS" groups. PhCI was calculated from the pharyngo-esophageal manometry analysis software (MMS, v9.5, Laborie Medical Technologies), and compared in these two groups. Of 67 children, 9 had abnormal VFSS (mean age 64 ± 50 months; 66.7% males), while 58 had normal VFSS (mean age 123 ± 55 months; 47% males). The mean PhCI in abnormal and normal VFSS groups was 82.00 ± 51.90 and 147.28 ± 53.89 mmHg.s.cm, respectively (p = 0.001). Subjects with abnormal VFSS were significantly younger than those with normal VFSS (p = 0.003). However, after adjusting for the VFSS result, age was no longer related to PhCI (p = 0.364). In subgroup analysis of children presenting with dysphagia, the mean PhCI in abnormal (9 subjects) and normal (36 subjects) VFSS groups was 82.00 ± 51.90 and 141.86 ± 50.39 mmHg.s.cm, respectively (p = 0.003). PhCI was significantly lower in children with abnormal VFSS than in those with normal VFSS. We did not find a significant impact of age on PhCI in our pediatric populations.

Normative High-Resolution Pharyngeal Manometry: Impact of Age, Size of System, and Sex on Primary Metrics and Pressure Stability.

There have been many reports of normative pharyngeal swallowing pressures using high-resolution pharyngeal manometry, but there is a fair amount of between-subject variance in reported pressure parameters. The purpose of this study was to put forward normative pharyngeal high-resolution manometry measures across the lifespan and investigate the effects of age, size of system, and sex. High-resolution pharyngeal manometry was performed on 98 healthy adults (43 males) between the ages 21 and 89. Pressure duration, maxima, integral, and within-individual variability metrics were averaged over 10 swallows of 10-ml thin liquid. Multiple linear and logistic regressions with model fitting were used to examine how pharyngeal pressures relate to age, pharyngeal size, and sex. Age was associated with tongue base maximum pressure, tongue base maximum variability, and upper esophageal sphincter-integrated relaxation pressure (F3,92 = 6.69; p < 0.001; adjusted R2 = 0.15). Pharyngeal area during bolus hold was associated with velopharynx integral (F1,89 = 5.362; p = 0.02; adjusted R2 = 0.05), and there was no significant model relating pharyngeal pressures to C2-C4 length (p < 0.05). Sex differences were best described by tongue base integral and hypopharynx maximum variability (χ2 = 10.27; p = 0.006; pseudo R2 = 0.14). Normative data reveal the distribution of swallow pressure metrics which need to be accounted for when addressing dysphagia patients, the importance of pressure interactions in normal swallow, and address the relative stability of swallow metrics with normal aging.

Investigating Parkinson's disease with dual high resolution pharyngeal manometry with impedance and videofluoroscopy.

To characterize pharyngeal function in people with Parkinson's Disease using both high resolution impedance manometry (HRIM) and videofluoroscopy (VFSS) and to explore correlations between VFSS and HRIM metrics. All participants received both VFSS and HRIM within 24 h-time window. A standard VFSS protocol (IDDSI 0: 1 mL, 3 mL, 20 mL, and 100 mL) was performed. A solid-state unidirectional catheter (36 pressure sensors) was used to acquire manometric data for triplicate swallows (IDDSI 0: 5 mL, 10 mL, 20 mL), quantitative swallow analysis was completed through Swallowtail™ and SwallowGateway™. Parameters were compared to published norms and statistical tests explored correlational associations (p < 0.05). Twenty-one participants (76% male; mean age 70 years, SD7.16) with mild-moderate severity PD were recruited with 73% reporting Eating Assessment Tool (EAT-10) scores ≥3 indicating swallow impairment. Compared to normal metrics, one third of participants had abnormally elevated hypopharyngeal contractile integral (HPCI), hypopharyngeal peak pressure, upper esophageal sphincter (UES) integrated relaxation pressure (UES IRP), and reduced UES maximum admittance. Five participants showed compromised swallow safety (Penetration-Aspiration Scale score ≥6). One third of participants had abnormal VFSS values for pharyngoesophageal segment (PES) opening duration, maximum PES opening distance, and maximum hyoid displacement measures. Some HRIM metrics had a strong correlation with pharyngeal VFSS measures (r > 0.60, p < 0.05). This study identifies early manometric signs of pharyngeal dysfunction in people with PD. The congruence of the VFSS and HRIM measures confirms the hypothesis of insidious early decline in swallow function in PD despite maintenance of airway safety (i.e., low aspiration rates).

Training for Awake, Office-Based Laryngeal Procedures-The Laryngology Fellow's Perspective.

The aim was to explore recent laryngology graduates' perspectives on their experience, competency, and challenges learning office-based procedures during fellowship training in the United States and Canada. Anonymous 22-item questionnaire survey was distributed electronically to fellowship-trained laryngologists having completed fellowship within past 5 years. Ninety fellowship-trained laryngologists between 2018 and 2022 were surveyed. Response rate was 48.9% (n = 44), 1 declined participation, with 20 different fellowship programs represented. Fellows were frequently provided the opportunity to act as primary surgeon for most procedures, except for laryngeal botulinum toxin injection, diagnostic laryngeal electromyography, trans-nasal esophagoscopy, secondary tracheoesophageal puncture, and high-resolution pharyngeal manometry. A majority reported high (n = 27, 62.8%) or moderate (n = 12, 27.9%) confidence with vocal fold injection augmentation. Various techniques were taught: transoral (74.4%), cricothyroid (74.4%), thyrohyoid (69.8%), transcartilagenous (14.0%), and catheter-needle (25.6%). Numerous statistically significant associations with independent procedure involvement and competence were identified. Laryngeal botulinum toxin injection was a procedure performed with high frequency but low volume of independent fellow involvement, and the procedure with which fellows reported wanting more practice learning. Most common training barriers included patient being awake, patient consenting to trainee performing the procedure, and the technical challenge/complexity of the procedure. Teaching methods/tools largely focused on informal debriefing (97.3%) and case by case troubleshooting (81.1%). Laryngology fellows are well trained with favorable perceived levels of competence for numerous office-based procedures, particularly vocal fold injection augmentation. Procedures for which fellows reported a low level of independent participation trended towards lower perceived competency. 5 Laryngoscope, 134:873-881, 2024.

The Manometric Representation of the Upper Esophageal Sphincter During the Resting State: A Descriptive Study.

The upper esophageal sphincter (UES) is the high-pressure zone marking the transition between the hypopharynx and esophagus. There is limited research surrounding the resting UES using pharyngeal high-resolution manometry (HRM) and existing normative data varies widely. This study describes the manometric representation of the resting UES using a clinically accessible method of measurement. Data were obtained from 87 subjects in a normative database of pharyngeal HRM with simultaneous videofluoroscopy. The resting UES manometric region was identified and ten measurement segments of this region were taken throughout the duration of the study using the Smart Mouse function within the manometry software. Intraclass correlation coefficients (ICC) were used to analyze within-subject reliability across measurements. Linear mixed-effects regression models were used to analyze how subject characteristics and manometric conditions influence resting UES pressure. There was excellent within-subject reliability between resting UES mean pressures (ICC = 0.96). In bivariate analysis, there were significant effects of age, number of sensors contained within the resting UES, and preceding swallow volume on mean resting UES pressure. For every 1 unit increase in age, there was a 0.19 unit decrease in resting UES pressure (p = 0.008). For every 1 unit increase in number of sensors contained within the resting UES, there was a 3.71 unit increase in resting UES pressure (p < 0.001). This study presents normative data for the resting UES, using a comprehensive and clinically accessible protocol that can provide standard comparison for the study of populations with swallowing disorders, particularly UES dysfunction, and provides support for UES-directed interventions.

Swallowing biomechanics in tracheostomised critically ill patients compared to age- and gender-matched healthy controls

ObjectiveThe mechanistic effects of a tracheostomy on swallowing are unclear. Pharyngeal high-resolution manometry with impedance (P-HRM-I) is a novel swallow assessment tool providing quantifiable metrics. This study aimed to characterise swallowing biomechanics in tracheostomised critically ill (non-neurological) patients. DesignCohort study. SettingAustralian tertiary hospital intensive care unit. ParticipantsTracheostomised adults, planned for decannulation. Main outcome measuresSwallowing assessment using P-HRM-I, compared to healthy age- and gender-matched controls. ResultsIn this tracheostomised cohort (n = 10), the Swallow Risk Index, a global measure of swallow function, was significantly elevated (p < 0.001). At the upper oesophageal sphincter (UOS), hypopharyngeal intrabolus pressure and UOS integrated relaxation pressure were significantly elevated (control 0.65 mmHg [-1.02, 2.33] v tracheostomy 13.7 mmHg [10.4, 16.9], P < 0.001; control −4.28 mmHg [-5.87, 2.69] v tracheostomy 12.2 mmHg [8.83, 15.6], P < 0.001, respectively). Furthermore, UOS opening extent and relaxation time were reduced (control 4.83 mS [4.60, 5.07] v tracheostomy 4.33 mS [3.97, 4.69], P = 0.002; control 0.52 s [0.49, 0.55] v tracheostomy 0.41 s [0.37, 0.45], P < 0.001, respectively). Total pharyngeal contractility (PhCI) measuring pharyngeal pressure generation was significantly elevated (control 199.5 mmHg cm.s [177.4, 221.6] v tracheostomy 326.5 mmHg cm.s [253.3, 399.7]; P = 0.001). ConclusionIn a critically ill tracheostomised cohort, UOS dysfunction was the prevalent biomechanical feature, with elevated pharyngeal pressures. Pharyngeal weakness is not contributing to dysphagia in this cohort. Instead, elevated pharyngeal pressures may represent a compensatory mechanism to overcome the UOS dysfunction. Further studies to extend these findings may inform the development of timely and targeted rehabilitation.

High-Resolution Pharyngeal Manometry: Recent Developments and Future Directions

High-Resolution Pharyngeal Manometry: Recent Developments and Future Directions

Clinical application of pharyngeal high-resolution manometry in Ear, Nose and Throat (ENT) practice

Sanith S. Cheriyan, Mistyka Schar, Charmaine M. Woods, Michal Szczesniak, Charles Cock, Taher I. Omari, Theodore Athanasiadis, Eng H. Ooi

Objective Pharyngeal Phenotyping in Obstructive Sleep Apnea With High-Resolution Manometry.

Drug-induced sleep endoscopy (DISE) is a commonly used diagnostic tool for surgical procedural selection in obstructive sleep apnea (OSA), but it is expensive, subjective, and requires sedation. Here we present an initial investigation of high-resolution pharyngeal manometry (HRM) for upper airway phenotyping in OSA, developing a software system that reliably predicts pharyngeal sites of collapse based solely on manometric recordings. Prospective cross-sectional study. An academic sleep medicine and surgery practice. Forty participants underwent simultaneous HRM and DISE. A machine learning algorithm was constructed to estimate pharyngeal level-specific severity of collapse, as determined by an expert DISE reviewer. The primary outcome metrics for each level were model accuracy and F1-score, which balances model precision against recall. During model training, the average F1-score across all categories was 0.86, with an average weighted accuracy of 0.91. Using a holdout test set of 9 participants, a K-nearest neighbor model trained on 31 participants attained an average F1-score of 0.96 and an average accuracy of 0.97. The F1-score for prediction of complete concentric palatal collapse was 0.86. Our findings suggest that HRM may enable objective and dynamic mapping of the pharynx, opening new pathways toward reliable and reproducible assessment of this complex anatomy in sleep.

Effects of the GABA(B) agonist baclofen on volitional swallowing in normal subjects.

The GABA(B) receptor agonist baclofen is known to suppress the rate of spontaneous swallowing but not pharyngeal muscle contraction. The extent to which baclofen may alter volitional swallowing is not currently known. We investigated the effects of baclofen in healthy subjects, hypothesizing that baclofen exposure would alter volume-regulation and/or piecemeal deglutition behaviors during volitional swallowing attempts. Pharyngeal high-resolution manometry impedance (P-HRM-I) protocol was used to assess swallowing function of 22 healthy adult volunteers (median 29 years) who were investigated on two occasions, receiving 40 mg baclofen (oral) 1 h before study, or placebo (randomized). Standard swallow function variables recommended by the pharyngeal HRM Working Group were derived for 5ml, 10ml, and 20 ml volumes of thin and extremely thick liquid challenges. Multiple swallow behaviors, comprising two swallows <5s apart, were characterized. The spontaneous swallow rate was also determined. Baclofen exposure had no overall significant effect on swallow variables. Upper esophageal sphincter pressure was weaker during exposure to baclofen, during both the pre-deglutitive and post-deglutitive phases of the swallow (p < 0.05 during thick liquid swallows). Piecemeal swallows, where the bolus is separated in two potions, were significantly more common during 20 ml boluses (p=0.002). Baclofen decreased the frequency of piecemeal deglutition overall. Baclofen has limited to no effect on volitional swallowing measures, however, does reduce the likelihood of initiation of piecemeal deglutition to large volume challenges.

Using high resolution manometry impedance to diagnose upper esophageal sphincter and pharyngeal motor disorders.

Oro-pharyngeal pathophysiology, including upper esophageal sphincter (UES) and pharyngeal disorders, can be assessed by pharyngeal high-resolution manometry impedance (P-HRM-I). We aimed to establish methodology to diagnose disorders utilizing P-HRM-I, hypothesizing that the objective measures could be used to diagnose disordered deglutition evidenced by greater aspiration scores. Patients (n=509, 18-91 years) were compared to controls (n=120, 20-94 years). Variables measuring UES relaxation, UES opening extent, intrabolus pressure, and pharyngeal contractile strength were derived for 10ml liquid swallows. Three associated pharyngeal pressurization patterns, which may be indicative of obstructed flow, were characterized: pan-pressurization (Type 1), distal compartmentalized pressurization (Type 2), and transient pressurization (Type 3). Deglutitive aspiration was determined from video fluoroscopy. UES relaxation pressure was best able to differentiate patients from controls (T 6.528, p < 0.0001). Patients with abnormal relaxation pressure (>8 mmHg) more frequently exhibited pharyngeal pressurization patterns and had adjunct evidence of reduced luminal distensibility (high intrabolus pressure and/or reduced UES opening). Utilizing this information, a diagnostic scheme was devised identifying 138 patients with UES disorder. A further 96 patients without evidence of UES disorder had abnormally weak pharyngeal pressures, confirming propulsive disorder. Amongst a sub-sample of 320 patients undergoing video fluoroscopy, those with pharyngeal pressurizations and adjunct evidence of reduced UES relaxation and/or distensibility had higher aspiration scores (Chi-square 60.169, p < 0.0001). P-HRM-I can provide evidence for UES disorder based on pharyngeal pressurization patterns and abnormal findings for UES relaxation pressure, UES opening, and intrabolus pressure. Measuring pharyngeal contractility requires further optimization.

Pharyngeal tongue base augmentation for dysphagia therapy: A prospective case series in patients post head and neck cancer treatment.

Dysphagia post head and neck cancer (HNC) multimodality treatment is attributed to reduced pharyngeal strength. We hypothesized that pharyngeal tongue base augmentation for dysphagia (PAD therapy) would increase pharyngeal pressures during swallowing thereby improving swallow symptoms. Adults with moderate-severe dysphagia post-HNC treatment had PAD therapy using a temporary filler (hyaluronic acid [HA]), with follow-up long-lasting lipofilling. Swallowing preprocedure and postprocedure was assessed with the Sydney Swallow Questionnaire (SSQ), High-Resolution Pharyngeal Manometry (HRPM), and Videofluoroscopic Swallowing Study (VFSS). Statistical comparison utilized paired tests. Six participants (all male; median age 64 years [IQR 56, 71]) underwent PAD therapy at a median of 47 [IQR 8, 95] months post-treatment. SSQ scores reduced from baseline (mean 1069 [95%CI 703, 1434]) to post-HA (mean 579 [76, 1081], p > 0.05), and post-lipofilling (491 [95%CI 913, 789], p=0.003, n=4). Individual participants demonstrated reduced Swallow Risk Index, Bolus Presence Time, and increased Upper Esophageal Sphincter opening, but mesopharyngeal contractile pressures were unchanged. VFSS measures of aspiration, residue, and severity were unchanged. Novel PAD therapy is safe and improves dysphagia symptoms. Biomechanical swallowing changes are suggestive of more efficacious bolus propulsion with conservative filler volume, but this was unable to resolve residue or aspiration measures.

Dysphagia in Parkinson's disease: Pharyngeal manometry and fiberoptic endoscopic evaluation

ObjectiveDysphagia is a common symptom in Parkinson's disease (PD) and it represents a negative prognostic factor because of its complications. This study is to evaluate pharyngeal dysphagia for boluses of various consistencies with Fiberoptic Endoscopic Evaluation of Swallowing (FEES) and Pharyngeal High-Resolution Manometry (PHRM) in a group of PD patients, making a comparison between the information provided by the two exams. MethodsGroup of 20 patients affected by PD was selected and initially subjected to a qualitative evaluation of the swallowing performing FEES. Subsequently, they were evaluated by PHRM to identify quantitative measures associated with pressures expressed by pharyngeal organs during swallowing. Values obtained in the study group were compared with those recorded in a group of 20 healthy subjects. ResultsStudy showed that Pmax (the maximum pressure elicited by the single pharyngeal muscle structures involved in swallowing) was significantly lower than the control group (p<0.05) for all the boluses and consistency tested, in particular for the Tongue base and the Cricopharyngeal muscle. Pmean pre-swallowing pressure (represents the mean value of a contraction in which basal and maximal pressure where normally calculated) was significantly higher compared to normal subjects for the Tongue base and the Cricopharyngeal muscle (p<0.05). Mean intra-swallowing pressure was higher for the Velopharynx and the Cricopharyngeal muscle, but lower for the tongue base. Pmax and Pmean at PHRM were altered independently to the degree of dysphagia detected at FEES, and they did not correlate either with the location of the residue or with the type of bolus. Images displayed at the FEES, found the corresponding biomechanical explanations in the PHRM, which also allowed us to quantify the extent of the dysfunction, through the calculation of the pressures generated in the various structures studied. ConclusionPHRM is particularly useful in the early detection of dysphagia, when FEES may still show no evidence of abnormal swallowing.

Use of Pharyngeal High-Resolution Manometry to Evaluate Dysphagia in Adults with Motor Neurone Disease: A Scoping Review

There has been a recent shift towards proactive dysphagia intervention in motor neurone disease (MND) to maintain physiological reserve. Pharyngeal high-resolution manometry (PHRM) can quantify swallowing pathophysiology to inform and evaluate proactive dysphagia intervention. This study aims to explore the current use of PHRM as a dysphagia evaluation in adults with MND. A scoping review based on the Joanna Briggs Framework was completed. Four electronic databases (PubMed, EMBASE, CINAHL and Web of Science core) were searched (inception to March 2021) by two independent researchers. Data were analysed according to (i) PHRM protocol and analysis methods and the feasibility of same, (ii) swallow biomechanics data and (iii) dysphagia intervention effects as measured by PHRM. Six studies with 78 people with MND (PwMND) were included. There was considerable variation in PHRM protocol and analysis methods. Five studies reported a 100% completion rate and three studies reported no adverse events. Swallow biomechanics data were reported across all studies. The effects of sensory stimulation, increased bolus consistency, effortful swallow and cricopharyngeal myotomy were evaluated using PHRM with 20 PwMND across four studies with varying effects. Literature on the use of PHRM in PwMND is limited. Variability in PHRM methods restricts comparison of metrics. PHRM appears to be a feasible tool for PwMND. PHRM can provide novel swallow physiology data in PwMND and quantify discrete effects of compensatory and surgical dysphagia interventions not detectable by videofluoroscopy or FEES. Further research on the effects of proactive dysphagia intervention as measured by PHRM is required.

Accuracy of High-Resolution Pharyngeal Manometry Metrics for Predicting Aspiration and Residue in Oropharyngeal Dysphagia Patients with Poor Pharyngeal Contractility.

Several physiological metrics can be derived from pharyngeal high-resolution impedance manometry (HRPM), but their clinical relevance has not been well established. We investigated the diagnostic performance of these metrics in relation to videofluoroscopic (VFS) assessment of aspiration and residue in patients with oropharyngeal dysphagia. We analyzed 263 swallows from 72 adult patients (22-91 years) with diverse medical conditions. Metrics of contractility, upper esophageal sphincter (UES) opening and relaxation, flow timing, intrabolus distension pressure, and a global Swallow Risk Index (SRI) were derived from pressure-impedance recordings using pressure-flow analysis. VFS data were independently scored for airway invasion and pharyngeal residue using the Penetration-Aspiration Scale and the Normalized Residue Ratio Scale, respectively. We performed multivariate logistic regression analyses to determine the relationship of HRPM metrics with radiological outcomes and receiver-operating characteristic (ROC) analysis to evaluate their diagnostic accuracy. We identified aspiration in 25% and pharyngeal residue in 84% of the swallows. Aspiration was independently associated with hypopharyngeal peak pressure < 65mmHg (HypoPeakP) [adjusted odds ratio (OR) 5.27; 95% Confidence Interval (CI) (0.99-28.1); p = 0.051], SRI > 15 [OR 4.37; 95% CI (1.87-10.2); p < 0.001] and proximal esophageal contractile integral (PCI) < 55mmHg·cm·s [OR 2.30; 95% CI (1.07-4.96); p = 0.034]. Pyriform sinus residue was independently predicted by HypoPeakP < 65mmHg [OR 7.32; 95% CI (1.93-27.7); p = 0.003], UES integrated relaxation pressure (UES-IRP) > 3mmHg [OR 2.96; 95% CI (1.49-5.88); p = 0.002], and SRI > 15 [OR 2.17; 95% CI (1.04-4.51); p = 0.039]. Area under ROC curve (AUC) values for individual HRPM metrics ranged from 0.59 to 0.74. Optimal cut-off values were identified. This study demonstrates the diagnostic value of certain proposed and adjunct HRPM metrics for identifying signs of unsafe and inefficient bolus transport in patients with oropharyngeal dysphagia.

Dysphagia in the elderly: A multidisciplinary approach

The process of eating and swallowing is a complex physiologic process requiring volitional as well as reflexive activities and involving multiple structural and functional elements. Dysphagia is a geriatric syndrome resulting in multiple negative health consequences. Dysphagia can have profound adverse influences, including malnutrition, dehydration, aspiration pneumonia, and depression poor quality of life in the elderly. With the aging of the population across the globe, health-care providers are encountering older patients with dysphagia either due to oropharyngeal or esophageal disease. Barium swallow remains a low-cost initial alternative for luminal and esophageal motility assessment. A variety of emerging modalities can help detect anatomical and functional deficits. These include fiberoptic endoscopic evaluation of swallowing, videofluoroscopic swallow study, high-resolution pharyngeal manometry, and esophagogastroduodenoscopy. This review provides a comprehensive review of diagnostic modalities and addresses several issues regarding the collaborative management of elderly persons with dysphagia, including a brief discussion on how swallowing mechanisms are affected by the aging process.

Pharyngeal Pressure Variability During Volitional Swallowing Maneuvers.

Within-individual pharyngeal swallowing pressure variability differs among pharyngeal regions in healthy individuals and increases with age. It remains unknown if pharyngeal pressure variability is impacted by volitional swallowing tasks. We hypothesized that pressure variability would increase during volitional swallowing maneuvers and differ among pharyngeal regions depending on the type of swallowing task being performed. Pharyngeal high-resolution manometry was used to record swallowing pressure data from 156 healthy participants during liquid (5 cc) or saliva swallows, and during volitional swallowing tasks including effortful swallow, Mendelsohn maneuver, Masako maneuver, or during postural adjustments. The coefficient of variation was used to determine pressure variability of velopharynx, tongue base, hypopharynx, and upper esophageal sphincter regions. Repeated-measures analysis of variance was used on log-transformed data to examine effects of pharyngeal region and swallowing tasks on swallow-to-swallow variability. There was a significant main effect of task with greater pressure variability for the effortful swallow (p = .002), Mendelsohn maneuver (p < .001), Masako maneuver (p = .002), and the head turn (p = .006) compared with normal effort swallowing. There was also a significant main effect of region (p < .01). In general, swallowing pressure variability was lower for the tongue base and upper esophageal sphincter regions than the hypopharynx. There was no significant interaction of task and region (effortful, p = .182; Mendelsohn, p = .365; Masako, p = .885; chin tuck, p = .840; head turn, p = .059; and inverted, p = .773). Pharyngeal swallowing pressure variability increases in healthy individuals during volitional swallowing tasks. Less stable swallow patterns may result when tasks are less automatic and greater in complexity. These findings may have relevance to swallowing motor control integrity in healthy aging and individuals with neurogenic dysphagia.

Pharyngo-Esophageal Modulatory Swallow Responses to Bolus Volume and Viscosity Across Time.

Objectives/HypothesisModulation of the pharyngeal swallow to bolus volume and viscosity is important for safe swallowing and is commonly studied using high‐resolution pharyngeal manometry (HRPM). Use of unidirectional pressure sensor technology may, however, introduce variability in swallow measures and a fixed bolus administration protocol may induce time and order effects. We aimed to overcome these limitations and to investigate the effect of time by repeating randomized measurements using circumferential pressure sensor technology.Study DesignSub‐set analysis of data from the placebo arm of a randomized, repeated measures trial.MethodsHRPM with impedance was recorded using a solid‐state catheter with 36 circumferential pressure sensors and 18 impedance segments straddling from hypopharynx to stomach. Testing included triplicates of 5, 10, and 20 ml thin liquid and 10 ml thick liquid boluses, the order of the thin liquid boluses was randomized. The swallow challenges were repeated approximately 10 minutes after finishing the baseline measurement.ResultsWe included 19 healthy adults (10/9 male/female; age 24.5 ± 4.1 year). Intrabolus pressure, all upper esophageal sphincter (UES) opening and relaxation metrics, and flow timing metrics increased with larger volumes. A thicker viscosity decreased UES relaxation time, UES basal pressure, and flow timing metrics, whereas UES opening extent increased. Pre‐swallow UES basal pressure and post‐swallow UES contractile integral decreased over time.ConclusionUsing circumferential pressure sensor technology, the effects of volume and viscosity were largely consistent with previous reports. UES contractile pressures reduced over time. The growing body of literature offers a benchmark for recognizing aberrant pharyngo‐esophageal motor responses.Level of Evidence3 Laryngoscope, 132:1817–1824, 2022

Swallowing biomechanics before and following multi-level upper airway surgery for obstructive sleep apnea.

The effect of contemporary multi-level upper airway surgery for obstructive sleep apnea on swallowing is unclear. This study assessed the biomechanical swallowing function in participants with obstructive sleep apnea pre- and post-modified uvulopalatopharyngoplasty and coblation channeling of the tongue. In this prospective, longitudinal study, adults diagnosed with moderate-severe obstructive sleep apnea who underwent modified uvulopalatopharyngoplasty and coblation channeling of the tongue surgery had swallowing biomechanics assessed using high-resolution pharyngeal manometry and analyzed with swallowgateway.com. Symptomatic swallowing difficulty was evaluated using the Sydney Swallow Questionnaire (≥ 234). General linear mixed-model analysis was conducted to evaluate the difference pre- and post-modified uvulopalatopharyngoplasty and coblation channeling of the tongue. Data are presented as mean [95% confidence intervals]. High-resolution pharyngeal manometry assessments were conducted in 10 participants (7 men; median age 50 [interquartile range 36-65]) preoperatively and repeated postoperatively at 9 months [interquartile range 6-13]. Self-reported dysphagia was unchanged following surgery (Sydney Swallow Questionnaire =149 [53, 447] to 168 [54, 247]; P = .093). High-resolution pharyngeal manometry outcomes indicated reduced mesopharyngeal pressures (148 [135, 161] to 124 [112, 137] mm Hg s cm; P = .011), reduced hypopharyngeal pressures (113 [101, 125] to 93 [84, 102] mm Hg s cm; P = 0.011), and reduced upper esophageal sphincter relaxation pressure (5 [4, 6] to 2 [1,3] mm Hg; P = 0.001) but no change to velopharyngeal pressures (135 [123, 147] to 137 [117, 157] mm Hg s cm; P = .850) postsurgery. Modified uvulopalatopharyngoplasty may have less implications on the swallow mechanism than previously suspected. In contrast, the reduction in mesopharyngeal contractile pressures associated with coblation channeling of the tongue, although within normal limits, may affect bolus propulsion. Biomechanical alterations were insufficient to worsen self-reported swallowing function. Schar MS, Omari TI, Woods CW, etal. Swallowing biomechanics before and following multi-level upper airway surgery for obstructive sleep apnea. J Clin Sleep Med. 2022;18(4):1167-1176.

The Natural Swallow: Factors Affecting Subject Choice of Bolus Volume and Pharyngeal Swallow Parameters in a Self-selected Swallow.

Predetermined volumes are used extensively throughout clinical assessment of swallowing physiology, but bolus volumes selected by an individual in their natural swallow can vary greatly from those used in structured assessment. This study aims to identify factors influencing self-selected volume and how the mechanics of self-selected volume swallows differ from predetermined volume swallows. We used pharyngeal high-resolution manometry (HRM) with simultaneous videofluoroscopy to measure swallowing pressures in the velopharynx, hypopharynx, and upper esophageal sphincter (UES). Data were collected from 95 healthy adults during thin liquid swallows of 10mL and a self-selected comfortable volume. An intraclass correlation coefficient (ICC) was calculated to analyze within-subject self-selected volume reliability. Linear mixed effects regression models were used to examine the association of subject characteristics with self-selected swallow volume and of self-selected volumes on pharyngeal swallowing pressures and timing events. Mean self-selected volume was 16.66 ± 7.70mL. Increased age (p = 0.002), male sex (p = 0.021), and increased pharyngeal hold area (p = 0.007) were significantly associated with increase in self-selected bolus volume. There was good reliability between subjects' individual swallow volumes (ICC = 0.80). Velopharyngeal maximum pressure and pressure integral, tongue base duration and maximum pressure, UES pre- and post-swallow maximum pressure, and overall pharyngeal contractile integral decreased significantly with self-selected boluses. Understanding a patient's natural swallow volume, and how their natural swallow functions, will be important for designing clinical evaluations that place stress on the patient's natural swallowing mechanics in order to assess for areas of dysfunction.