Reference Values for Healthy Swallowing Across the Range From Thin to Extremely Thick Liquids

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.

A Preliminary Study of Vallecular Bolus Aggregation in Healthy Swallowing of Solid Food Boluses

OBJECTIVE

The pharyngeal swallow typically begins within 400 ms following the arrival of a liquid bolus in the pharynx. By contrast, processed food particles aggregate in the valleculae prior to swallow initiation. With solid foods, swallow reaction time (SRT), the interval between bolus passing the ramus of mandible and hyoid burst onset (HYB) can be subdivided into components of vallecular aggregation time (VAT) and the subsequent end of aggregation to hyoid burst interval (EOA-to-HYB). However, expected durations of these timing measures remain unclear. We aimed to study bolus aggregation in healthy swallowing for International Dysphagia Diet Standardisation Initiative Food Levels 5 (minced and moist [MM5]), 6 (soft and bite-sized [SB6]), and 7 (regular [RG7]). Understanding typical patterns and durations of vallecular aggregation with solids in healthy swallowing will inform the identification of impaired swallow timing in patient populations.

DESIGN

Twenty healthy adults (10 males, Mage = 28 years, range: 23-55 years) swallowed two boluses each of MM5, SB6, and RG7 foods in videofluoroscopy. Blinded duplicate ratings determined bolus location at swallow onset, SRT, VAT, and EOA-to-HYB. Texture-based differences were measured using Friedman's tests. Bolus location was at/above the valleculae at swallow onset for 85% of boluses, with no differences by texture. SRT, VAT, and EOA-to-HYB did not vary by texture, with overall median values (interquartile range) of 99 ms (-66 to 743 ms) for SRT, 347 ms (66 to 891 ms) for VAT, and -132 ms (-231 to -83 ms) for EOA-to-HYB.

CONCLUSIONS

These data corroborate prior evidence that it is not unusual for food particles to aggregate in the valleculae prior to swallow initiation in healthy swallowing. However, durations of vallecular aggregation are typically < 1 s in healthy adults.

Effects of Cervical Bracing on Elderly Patients With Dysphagia

PURPOSE

This study aimed to determine if cervical bracing with a PMT collar increases risk of airway invasion and pharyngeal residue in elderly patients with dysphagia. Additionally, it aimed to identify patient preference for cervical bracing during deglutition.

METHOD

Twenty-one patients underwent a videofluoroscopic swallow study. Thin liquid, nectar thick liquid, pudding, and cracker were administered with cervical collar on and off with order of condition randomized. The Penetration-Aspiration Scale (PAS) was used to grade swallows, with McNemar's test of symmetry used to determine whether the categorical PAS score was similar between conditions. Pharyngeal residue was measured following swallows. Patients were asked which condition they preferred, and which was more comfortable with "no difference" being a selection.

RESULTS

No significant difference in PAS categorization score was measured for any consistency (p = .317-.919). Significantly more pyriform sinus residue was measured in the collar off condition (p = .003), albeit amounts were within normative range, with no difference measured in vallecula residue between conditions (p = .939). Forty-five percent of participants preferred to swallow with the collar off, while 55% indicated no preference. Forty-one percent of participants indicated increased comfort with collar off, while 59% indicated no difference in comfort. No participant preferred swallowing or indicated increased comfort with the collar on.

CONCLUSIONS

Presence of a cervical collar in elderly patients with dysphagia did not result in a significant difference in airway invasion or total pharyngeal residue. There was significantly more residue in the pyriform sinuses when cervical bracing was removed. The majority of patients did not indicate a difference in preference or comfort between collar on/off conditions.

Pharyngeal Structure and Dysphagia in Patients with Parkinson's Disease and Related Disorders

Pharyngeal muscle changes occur in patients with Parkinson's disease and related disorders (PRD); however, the association between the structural alterations in the pharynx and the symptoms of dysphagia remains unclear. We assessed structural changes and contractile forces by measuring pharyngeal wall thickness and width. We aimed to define the pharyngeal measurements and determine their value as diagnostic tools for dysphagia. The pharyngeal wall thickness (PWT), pharyngeal width at rest (PWR), and shortest pharyngeal width at swallowing (PWS) were measured using lateral neck roentgenograms and videofluoroscopic swallowing study. We compared the PWR and PWT between the PRD and control groups using an independent t-test. The Kendall correlation test was performed on the radiological data of the pharynx (PWT, PWR and PWS), dysphagia scales (Penetration-Aspiration scale [PAS] and Dysphagia Outcome and Severity Scale [DOSS]), and Hoehn and Yahr scale (HY scale). The PWT was smaller and the PWR greater in the PRD than in the control group (p < 0.05). The dysphagia scales (PAS and DOSS) were correlated with the radiological data (PWT and PWS) and the HY scale (p < 0.05). The HY scale score also correlated with the PWT (p < 0.05). The optimal cutoff points of the PWT and PWR for predicting aspiration were 4.05 and 16.05 mm in the PRD group, respectively. Using the PWT, PWR and PWS, muscle atrophy and contractile strength of the pharynx can be estimated. The combination of the PWT and PWR can be a simple indicator for predicting swallowing disorders at the bedside.

Normal Variations in Upper Esophageal Sphincter Function During Deglutition: A Secondary Analysis of Videofluoroscopic Data

OBJECTIVE

Cricopharyngeal dysfunction is a common potential cause of pharyngoesophageal dysphagia. Contextual factors (i.e., personal demographics and bolus properties) appear to impact upper esophageal sphincter (UES) function but have yet to be assessed collectively in a large-scale study using psychometrically sound swallow task procedures. Using a standardized and validated videofluoroscopic approach, we investigated the collective effects of age, sex, and swallow task on UES opening duration (UESOdur) and UES maximum distension (UESmax) in a large sample of healthy adults.

METHODS

UESOdur and UESmax data were analyzed from existing videofluoroscopic images of 195 healthy adults (21-89 years old) across seven swallow tasks (thin liquid to viscous liquids, puree, and a solid). Generalized estimating equation modeling captured the effects of the aforementioned contextual factors (α = 0.05).

RESULTS

UESOdur significantly increased with age, while UESmax had an inverse relationship. Females had significantly wider UESmax. UESOdur of 5 mL thin liquid was significantly shorter than all other liquid swallow tasks, while solid had an inverse effect. Compared to 5 mL thin liquid, all other swallow tasks resulted in significantly wider UESmax. Mildly and moderately thick liquid significantly increased UESOdur when isolating viscosity. UESmax was significantly wider with mildly and moderately thick liquid and puree than thin liquid. When isolating volume, cup sip thin liquid increased both measures significantly relative to 5 mL.

CONCLUSION

Age, sex, and swallow task can influence the normal timing and extent of UES movement. These collective effects contribute to normal variability in UES function and should be considered for clinical decision-making.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:2306-2315, 2024.

Evaluating Anterior and Posterior Oral Tongue Contributions to Pressure Generation: A Comparison Between Regular and Effortful Saliva Swallows

PURPOSE

This study determined the contributions of the anterior and posterior tongue regions in tongue pressure generation during regular saliva swallows (SSs) and effortful swallows (ESs) completed under two different instructions. The association between tongue pressure and perceived effort to swallow was also examined.

METHOD

Forty healthy adults without swallowing disorders participated in this study, divided into two age groups: 20 younger (Mage = 21.95 years, SD = 4.43) and 20 older (Mage = 70.10 years, SD = 4.30). Simultaneous data acquisition involved submental surface electromyography, tongue manometry, and a visual analog scale across swallowing conditions (SS, ES with tongue emphasis, and ES with pharyngeal squeezing). The main outcome measures were tongue pressure during swallowing and perceived effort to swallow.

RESULTS

Overall tongue pressure during ESs with tongue emphasis and with pharyngeal squeezing was greater than that during SSs (R2 = .78, p < .001). Moreover, tongue pressure during the ES with tongue emphasis was greater than that during the ES with pharyngeal squeezing (t = 25.63, p < .001). The posterior tongue region generated more pressure during SSs (R2 = .64, p < .001) and the ES with tongue emphasis (R2 = .55, p < .001) than the anterior tongue. Finally, a positive correlation was found between perceived effort and tongue pressure during swallowing (r = .75, 95% CI [0.72, 0.77]).

CONCLUSIONS

Tongue pressure generation was affected by the type of instruction used to elicit ESs, and the posterior tongue showed relatively greater pressure contributions than the anterior tongue for ESs with tongue emphasis and SSs. Furthermore, age-related declines in pressure generation during swallowing were not evidenced in this study, underscoring the ability of healthy older individuals to appropriately modulate lingual pressure during ESs. Last, our results showed that the visual analog scale is a simple tool for rating swallowing effort during ESs, supporting its potential clinical use to train ESs.

The Impact of Videofluoroscopic Pulse Rate on Duration and Kinematic Measures in Infants and Adults with Feeding and Swallowing Disorders

This investigation assessed the impact of temporal resolution during a videofluoroscopic evaluation of swallowing (VFSS) on measures of duration and kinematics. Thirty adult and ten infant swallow studies, all acquired at 30 frames and 30 pulses per second, were obtained from a New Mexico hospital. All swallow studies were altered to simulate 15 and 5 pulses per second. Duration measures included pharyngeal response time, duration of upper esophageal sphincter (UES) opening, velopharyngeal closure duration and total swallow duration. Kinematic measures were assessed in adults only and included peak hyoid position and extent of UES opening during the swallow. Analysis of outcome measures was performed and compared across the three temporal resolutions (30, 15, and 5 pulses per second). For data points where normative values are available, we evaluated the impact of temporal resolution on clinical determination (i.e., did a change in pulse rate alter the clinical classification). Kinematic and duration measures were altered with changes in pulse rate and these changes increased as temporal resolution decreased. For outcome measures where normative values are available, accuracy of clinical determination decreased with decreased pulse rate. Temporal resolution impacts duration and kinematic measures. However, the direction of these changes is unpredictable, indicating sensitivity and specificity are both affected. Without a predictable impact, the use of lower pulse rates may alter clinical impressions and treatment recommendations yielding inappropriate treatment goals and treatment duration.

A Large Cohort Analysis of Epiglottic Phenotypes and Pharyngeal Residue

OBJECTIVE

To describe the phenotypic characteristics of the epiglottis at rest and their impact on vallecular residue.

METHODS

Videofluoroscopic studies (VFSS) were pooled from 2 Laryngology practices, and Image J was used to measure epiglottic anatomic features at rest. Studies were rated by the MBSImp and presence of vallecular residue following swallow of thin and puree boluses. A conditional inference tree analysis was performed to isolate which epiglottic parameters were risk factors for presence of vallecular reside followed by logistic regression.

RESULTS

The majority of patients had a normal shaped epiglottis, followed by omega shape. The mean angle of the epiglottis from the hyoid was approximately 90°. Only abnormal epiglottic movement was associated with increased risk of residue for thin boluses (OR 35.09, CI 10.93-158.66, P < .001). However, in those with normal epiglottic movement, age >70 years old was associated with increased risk of residue (OR 3.98, CI 1.73-9.23, P = .001). For puree boluses, a normal or omega shaped epiglottis was associated with residue (OR 5.19, CI 2.41-11.51, P < .001), and this relationship was further modulated by increased distance of the epiglottic tip from the posterior pharyngeal wall. No other anatomic features of the resting epiglottis were associated with residue. Comorbidities potentially affecting swallow were infrequent in the cohort and were not associated with residue.

CONCLUSION

Abnormal epiglottic movement is associated with aspiration, and in this study we find that abnormal epiglottic movement increases the risk of vallecular residue and that older age is a risk factor for residue. The resting properties of the epiglottis do not appear to be associated with abnormal epiglottic movement or residue.

Polysaccharide-dextrin thickened fluids for individuals with dysphagia: recent advances in flow behaviors and swallowing assessment methods

The global aging population has brought about a pressing health concern: dysphagia. To effectively address this issue, we must develop specialized diets, such as thickened fluids made with polysaccharide-dextrin (e.g., water, milk, juices, and soups), which are crucial for managing swallowing-related problems like aspiration and choking for people with dysphagia. Understanding the flow behaviors of these thickened fluids is paramount, and it enables us to establish methods for evaluating their suitability for individuals with dysphagia. This review focuses on the shear and extensional flow properties (e.g., viscosity, yield stress, and viscoelasticity) and tribology (e.g., coefficient of friction) of polysaccharide-dextrin-based thickened fluids and highlights how dextrin inclusion influences fluid flow behaviors considering molecular interactions and chain dynamics. The flow behaviors can be integrated into the development of diverse evaluation methods that assess aspects such as flow velocity, risk of aspiration, and remaining fluid volume. In this context, the key in-vivo (e.g., clinical examination and animal model), in-vitro (e.g., the Cambridge Throat), and in-silico (e.g., Hamiltonian moving particles semi-implicit) evaluation methods are summarized. In addition, we explore the potential for establishing realistic assessment methods to evaluate the swallowing performance of thickened fluids, offering promising prospects for the future.

The Effect of Oropharyngeal Resting Tremor on Swallowing Function in a Clinical Cohort of People with Parkinson's Disease

Parkinson's Disease (PD) is a progressive neurodegenerative disease, with hallmark symptomology typically consisting of tremor, bradykinesia, and rigidity. Though the classic "pill-rolling" rest tremor in the hand or upper limb are often the most salient, it can occur throughout the body including the lower limbs, jaw, face, or tongue. There have been investigations into other motor related phenomena potentially affecting swallow function in PwPD previously. However, there have been no investigations of how oropharyngeal resting tremor in structures such as the tongue or larynx explicitly affects swallowing physiology. A retrospective analysis of previously conducted VFSS on 34 patients diagnosed with idiopathic PD (IPD) was performed to examine how individuals that displayed resting tremor during VFSS (Tremor +) and those who did not (Tremor-) differ in swallowing function. Measures of swallowing function including timing intervals of key swallow events, post-swallow residue, and penetration-aspiration scale (PAS) scores were recorded, and key demographic information including time since diagnosis and medication status were extracted from the medical records available. Multivariate models were used to identify differences between tremor groups for timing intervals and post-swallow residue, and chi-squares were computed for differences in PAS score distribution by group and bolus. Sixty-eight percent (23/34) of this sample displayed oropharyngeal resting tremor in at least one structure during VFSS. There were no instances of other tremor types observed in this sample. All participants were taking medication to manage PD symptomology. Significant effects of tremor group were observed for swallow timing intervals related to airway closure (p < 0.001), post-swallow residue (p < 0.05), and swallow safety at the bolus level in the Tremor + group (p < 0.001). These results suggest that PwPD who present with resting tremor in oropharyngeal structures may manifest with different variations in swallowing physiology, including altered timings of swallow events, increased pharyngeal residue, and greater associations of airway invasion with thinner and larger volume boluses. This study highlights the need for substantially more research into how motor fluctuations and phenotypes of PwPD contribute to alterations in swallowing function.

Contribution of Wireless Wi-Fi Intraoral Cameras to the Assessment of Swallowing Safety and Efficiency

BACKGROUND

Clinical evaluation of swallowing provides important clinical information but is limited in detecting penetration, aspiration, and pharyngeal residue in patients with suspected dysphagia. Although this is an old problem, there remains limited access to low-cost methods to evaluate swallowing safety and efficiency.

PURPOSE

The purpose of this technical report is to describe the experience of a single center that recently began using a wireless Wi-Fi intraoral camera for transoral endoscopic procedures as an adjunct to clinical swallowing evaluation. We describe the theoretical structure of this new clinical evaluation proposal. We present descriptive findings on its diagnostic performance in relation to videofluoroscopic swallowing study as the gold standard in a cohort of seven patients with dysphagia following head and neck cancer. We provide quantitative data on intra- and interrater reliability. Furthermore, this report discusses how this technology can be applied in the clinical practice of professionals who treat patients with dysphagia and provides directions for future research.

CONCLUSIONS

This preliminary retrospective study suggests that intraoral cameras can reveal the accumulated oropharyngeal secretions and postswallow pharyngolaryngeal residue in patients with suspected dysphagia. Future large-scale studies focusing on validating and exploring this contemporary low-cost technology as part of a clinical swallowing evaluation are warranted.

The effect of liquid consistency on penetration-aspiration: a Bayesian analysis of two large datasets

Introduction

Thickened liquids are commonly recommended to reduce the risk of penetration-aspiration. However, questions persist regarding the impact of bolus consistency on swallowing safety. The common practice of summarizing Penetration-Aspiration Scale (PAS) scores based on worst scores is a bias in prior analyses. The aim of this study was to examine the impact of liquid consistency on PAS scores using a Bayesian multilevel ordinal regression model approach, considering all scores across repeated bolus trials. A second aim was to determine whether PAS scores differed across thickener type within consistency.

Methods

We analyzed two prior datasets (D1; D2). D1 involved 678 adults with suspected dysphagia (289 female; mean age 69 years, range 20-100). D2 involved 177 adults (94 female; mean age 54 years, range 21-85), of whom 106 were nominally healthy and 71 had suspected dysphagia. All participants underwent videofluoroscopy involving ≥3 boluses of 20% w/v thin liquid barium and of xanthan-gum thickened barium in mildly, moderately and extremely thick consistencies. D2 participants also swallowed trials of slightly thick liquid barium, and starch-thickened stimuli for each thickened consistency. Duplicate blinded rating yielded PAS scores per bolus, with discrepancies resolved by consensus. PAS ratings for a total of 8,185 and 3,407 boluses were available from D1 and D2, respectively. Bayesian models examined PAS patterns across consistencies. We defined meaningful differences as non-overlapping 95% credible intervals (CIs).

Results

Across D1 and D2, penetration occurred on 10.87% of trials compared to sensate (0.68%) and silent aspiration (1.54%), with higher rates of penetration (13.47%) and aspiration (3.07%) on thin liquids. For D1, the probability of a PAS score > 2 was higher for thin liquids with weighted PAS scores of 1.57 (CI: 1.48, 1.66) versus mildly (1.26; CI: 1.2, 1.33), moderately (1.1; CI: 1.07, 1.13), and extremely thick liquids (1.04; CI: 1.02, 1.08). D2 results were similar. Weighted PAS scores did not meaningfully differ between thin and slightly thick liquids, or between starch and xanthan gum thickened liquids.

Discussion

These results confirm that the probability of penetration-aspiration is greatest on thin liquids compared to thick liquids, with significant reductions in PAS severity emerging with mildly thick liquids.

Impact of Varying Transcutaneous Electrical Stimulation Pulse Frequency on Swallow Timing Measures in Healthy Adults

The impaired swallow timing subsequent to dysphagia or aging can potentially endanger swallowing safety and efficiency. Preliminary evidence has suggested that transcutaneous electrical stimulation (TES) may have the potential to affect swallow timing. However, limited knowledge exists regarding which TES parameters can optimize swallow timing. Pulse frequency is one of the primary TES parameters that can affect the quality of muscle contraction. Yet, no clear information exists regarding how changing pulse frequency impacts the timing of swallowing events. This study aimed to investigate the varying effects of submental TES pulse frequency on swallowing events during and post-15-min TES administration. Twenty-six healthy individuals between the ages of 20 and 54 participated in this study and were assigned to high pulse frequency (HPF) (80 Hz) or low pulse frequency (LPF) (30 Hz) groups. Videofluoroscopic swallowing study (VFSS) was used to record swallowing. Three trials of 10 mL pureed mixed with barium sulfate were presented under three different conditions, including pre-TES, during TES, and post-TES, in which measures were taken following 15 min of TES delivery. The swallow timing events that were measured in each condition were time to maximum hyoid elevation, time to maximum laryngeal elevation, laryngeal vestibule closure reaction time (LVCrt), laryngeal vestibule closure duration (LVCd), time to maximum pharyngeal constriction, and pharyngoesophageal segment (PES) opening duration. No significant pulse frequency effect was found on any swallow timing measures during or after 15 min of TES. Both protocols decreased the duration of some swallowing events during TES including time to maximum hyoid elevation [p < 0.017, ηp2 = 0.185], LVCrt [p < 0.032, ηp2 = 0.158], and time to maximum pharyngeal constriction [p < 0.034, ηp2 = 0.155]. None of the significant TES effects were continued when TES ceased after 15 min. Overall, both protocols have comparable immediate effects on shortening the duration of some swallowing events during TES. Future clinical trials should examine whether these physiologic timing changes can lead to safer and more efficient swallows in patients with dysphagia.

The Effectiveness of Slightly Thick Liquids for Improving Swallowing in Bottle-Fed Children With Aerodigestive Concerns

Purpose

Strategies for facilitating safe and functional bottle feeding in children with dysphagia include selecting nipples that reduce flow rate, pacing, altered positioning, and thickening liquid consistencies. We aimed to determine the impact of slightly thick liquids on swallowing through retrospective review of a convenience sample of clinical videofluoroscopic swallowing studies (VFSS) from 60 bottle-fed children (21 boys and 39 girls, mean age of 9.9 months) referred due to suspected aspiration.

Method

Eligible VFSS exams were those in which the child swallowed both thin and slightly thick barium (40% w/v Varibar barium) using the same nipple. VFSS sequences (i.e., uninterrupted portions of the VFSS recording) were randomly assigned in duplicate for rating by trained raters; discrepancies were resolved by consensus. Parameters measured included number of swallows/sequence, sucks/swallow, swallow and sequence duration, number and timing of penetration or aspiration events, laryngeal vestibule closure integrity, and pharyngeal residue. Chi-square tests, linear mixed-model analyses of variance, and Wilcoxon signed-ranks tests identified consistency effects.

Results

There were no aspiration events in these recordings. Slightly thick liquids resulted in significantly fewer penetration events (p < .05), increased sucks/swallow, fewer swallows/sequence, and longer swallow and sequence durations. The number of children with ≥ 1 sequence showing pyriform sinus residue was significantly higher with slightly thick liquids.

Conclusions

Slightly thick liquids can be effective in reducing penetration in bottle-fed children with dysphagia. However, slightly thick liquids may also lead to a safety-efficiency trade-off, with increased risk of pyriform sinus residue. Thickening for children with dysphagia should be considered only when other approaches are not effective. Overthickening should be avoided to limit negative impact on swallowing efficiency.

Prediction of Pharyngeal 3D Volume Using 2D Lateral Area Measurements During Swallowing

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

Impacts of Deep Brain Stimulation of the Globus Pallidus Internus on Swallowing: A Retrospective, Cross-Sectional Study

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

Quantifying Oropharyngeal Swallowing Impairment in Response to Bolus Viscosity

PURPOSE

The purpose of this study was to test the feasibility for quantifying changes in oropharyngeal swallowing impairment in response to alteration in bolus viscosity using a reliable and valid method of observational measurement-the Modified Barium Swallow Impairment Profile (MBSImP).

METHOD

This retrospective analysis included a heterogeneous cohort of 119 patients with suspected dysphagia that underwent a videofluoroscopic swallowing study as part of clinical care. Using consensus scoring, two expert clinicians assigned MBSImP scores to components related to oropharyngeal swallowing function between two bolus viscosities (thin liquid and pudding): epiglottic movement, laryngeal elevation, anterior hyoid excursion, tongue base retraction, pharyngeal stripping wave, and pharyngoesophageal segment opening (PESO). Comparisons between the two bolus viscosities were investigated for each component.

RESULTS

Higher (worse) scores were observed in the thin-liquid trial compared with the pudding trial for the following MBSImP components: anterior hyoid excursion (p = .03), epiglottic movement (p < .001), pharyngeal stripping wave (p < .001), and PESO (p = .002). Lower (better) scores were observed in the liquid trial compared with the pudding trial for one component-tongue base retraction (Component 15) only (p < .001).

CONCLUSION

These findings provide further evidence for positive influences of viscosity on the swallow mechanism, including influences of sensory feedback on the sensorimotor swallow program.

Impact of Quantitative Videofluoroscopic Swallowing Measures on Clinical Interpretation and Recommendations by Speech-Language Pathologists

Quantitative measures are available for adult videofluoroscopic swallow study (VFSS) analysis but are yet to be seen routinely in clinical practice. This study explores agreement between traditional observational analysis and quantitative analysis, and the impact of analytical approaches on subsequent diagnosis and recommendations. One hundred adults referred for VFSSs with swallowing concerns were administered a standardised VFSS protocol. All VFSSs were analysed using three approaches: (1) a traditional observational analysis typically used by treating speech-language pathologists (SLPs), (2) quantitative analysis by two independent raters, and (3) binary subjective analysis by 11 independent raters. Three metrics were focussed on; pharyngeal constriction (PC), hyoid displacement (Hmax) and pharyngoesophageal segment opening (PESmax). All raters were blinded to others' ratings. Treating SLPs using traditional observational analysis were provided with no instructions. Quantitative analysis used published Leonard and Kendall digital displacement measures. Binary subjective analysis involved rating each VFSS as normal versus impaired for the three metrics above. Treating SLPs using traditional observational analysis and quantitative analysis raters independently provided diagnostics and treatment plans. PC, Hmax and PESmax achieved fair agreement (Kappa = 0.33-0.36) between binary subjective analysis compared to substantial agreement (ICC = 0.77-0.94) for quantitative analysis. Reports of impairment were significantly lower in the traditional observational and binary subjective analyses compared with studies rated using the quantitative analysis (p < 0.05). Consequently, this resulted in significantly less rehabilitation recommendations when traditional observational analysis was used in comparison to the quantitative analysis. Quantitative measures to analyse VFSSs can be used in clinical practice producing increased inter-rater agreement and supporting more targeted rehabilitation recommendations than using a traditional observational VFSS analysis alone.

Quantitative Analysis of Temporal Parameters Correlated with Aspiration and Lesion Location in Stroke Patients

The purpose of this study was to identify differences in temporal parameters correlating to the presence of aspiration and the severity of penetration-aspiration scale (PAS) in patients with dysphagia after stroke. We also investigated whether there was a significant difference in temporal parameters based on the location of the stroke lesion. A total of 91 patient videofluoroscopic swallowing study (VFSS) videos of stroke patients with dysphagia were retrospectively analyzed. Various temporal parameters including oral phase duration, pharyngeal delay time, pharyngeal response time, pharyngeal transit time, laryngeal vestibule closure reaction time, laryngeal vestibule closure duration, upper esophageal sphincter opening duration and upper esophageal sphincter reaction time were measured. Subjects were grouped by the presence of aspiration, PAS score, and location of the stroke lesion. Pharyngeal response time, laryngeal vestibule closure duration, and upper esophageal sphincter opening duration were significantly prolonged in the aspiration group. These three factors showed positive correlation with PAS. In terms of stroke lesion, oral phase duration was significantly prolonged in the supratentorial lesion group, while upper esophageal sphincter opening duration was significantly prolonged in the infratentorial lesion group. We have demonstrated that quantitative temporal analysis of VFSS can be a clinically valuable tool identifying dysphagia pattern associated with stroke lesion or aspiration risk.

Videofluoroscopic measures of swallowing in people with stable COPD compared to healthy aging

PURPOSE

Swallowing impairment is a serious extra-pulmonary manifestation of Chronic Obstructive Pulmonary Disease (COPD). Previous studies suggest that individuals with stable COPD show atypical values for several videofluoroscopy measures of swallowing, compared to healthy adults under age 60. However, it is unclear to what degree these changes are attributable to healthy aging. In this study, we aimed to clarify how swallowing in people with stable COPD differs from age-matched healthy controls.

METHODS

We performed a retrospective analysis of videofluoroscopy data from two previously-collected datasets: a) a sample of 28 adults with stable COPD (18 male); b) a sample of 76 healthy adults, from which 28 adults were selected, matched for sex and age to participants in the COPD cohort. In both prior studies, participants swallowed 20% w/v liquid barium prepared in different consistencies (thin; mildly, moderately, and extremely thick). Blinded duplicate ratings were performed according to a standard procedure, yielding measures of laryngeal vestibule closure (LVC) integrity and timing, swallow timing, upper esophageal sphincter (UES) opening, pharyngeal constriction and pharyngeal residue. Mann-Whitney U tests and odds ratios were performed to determine significant group differences (p<.05).

RESULTS

Across the consistencies tested, participants with COPD showed significantly shorter durations of LVC, earlier onsets and shorter durations of UES opening, and reduced pharyngeal constriction. No significant differences were seen in other measures.

CONCLUSION

These results point to features of swallowing in people with stable COPD that differ from changes seen with healthy aging, and which represent risks for potential aspiration.

Application of deep learning technology for temporal analysis of videofluoroscopic swallowing studies

Temporal parameters during swallowing are analyzed for objective and quantitative evaluation of videofluoroscopic swallowing studies (VFSS). Manual analysis by clinicians is time-consuming, complicated and prone to human error during interpretation; therefore, automated analysis using deep learning has been attempted. We aimed to develop a model for the automatic measurement of various temporal parameters of swallowing using deep learning. Overall, 547 VFSS video clips were included. Seven temporal parameters were manually measured by two physiatrists as ground-truth data: oral phase duration, pharyngeal delay time, pharyngeal response time, pharyngeal transit time, laryngeal vestibule closure reaction time, laryngeal vestibule closure duration, and upper esophageal sphincter opening duration. ResNet3D was selected as the base model for the deep learning of temporal parameters. The performances of ResNet3D variants were compared with those of the VGG and I3D models used previously. The average accuracy of the proposed ResNet3D variants was from 0.901 to 0.981. The F1 scores and average precision were 0.794 to 0.941 and 0.714 to 0.899, respectively. Compared to the VGG and I3D models, our model achieved the best results in terms of accuracy, F1 score, and average precision values. Through the clinical application of this automatic model, temporal analysis of VFSS will be easier and more accurate.

Profiling Number of Swallows per Bolus and Residue in Individuals With Amyotrophic Lateral Sclerosis

PURPOSE

Swallowing efficiency impairments are the most prevalent and earliest manifestation of dysphagia in people with amyotrophic lateral sclerosis (pALS). We aimed to profile number of swallows elicited in pALS across thin liquid, moderately thick liquid, extremely thick liquid, and crackers compared to expected healthy reference data and to determine relationships between degree of pharyngeal residue, number of elicited swallows, and swallowing safety.

METHOD

pALS underwent standardized videofluoroscopic swallowing studies of 10 bolus trials. Trained raters performed duplicate, independent, and blinded ratings to derive Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) efficiency and safety grades and Analysis of Swallowing Physiology: Events, Kinematics, and Timing (ASPEKT) percent total pharyngeal residue. Number of swallows per bolus was quantified (1 = typical, 2 = atypically high, 3 = extremely high). Kruskal-Wallis, Pearson chi-square, and odds ratio analyses were performed at bolus and participant levels.

KEY RESULTS

At the bolus level (N = 2,523), number of swallows per bolus was observed to be, in rank order, as follows: atypically high (49.1%), extremely high (28.5%), and typical (22.4%). Mean number of swallows significantly differed by International Dysphagia Diet Standardisation Initiative level (p < .0001), with a higher number of swallows elicited in pALS for moderately thick versus thin liquids, extremely thick liquids, and crackers, p < .0001. Number of swallows per bolus increased with increasing DIGEST efficiency grades (p < .0001). Positive correlations were observed between ASPEKT percent residue and number of swallows for thin (r = .24) and moderately thick (r = .16) liquids, p < .05. DIGEST efficiency and safety grades were not significantly associated (p > .05).

CONCLUSION AND INFERENCES

pALS demonstrated a higher number of swallows per bolus compared to healthy reference data that may represent a compensation for reductions in swallowing efficiency to clear pharyngeal residue.

Reference Values for Videofluoroscopic Measures of Swallowing: An Update

PURPOSE

It is essential that clinicians have evidence-based benchmarks to support accurate diagnosis and clinical decision making. Recent studies report poor reliability for diagnostic judgments and identifying mechanisms of impairment from videofluoroscopy (VFSS). Establishing VFSS reference values for healthy swallowing would help resolve such discrepancies. Steele et al. (2019) released preliminary reference data for quantitative VFSS measures in healthy adults aged < 60 years. Here, we extend that work to provide reference percentiles for VFSS measures across a larger age span.

METHOD

Data for 16 VFSS parameters were collected from 78 healthy adults aged 21-82 years (39 male). Participants swallowed three comfortable sips each of thin, slightly, mildly, moderately, and extremely thick barium (20% w/v). VFSS recordings were analyzed in duplicate by trained raters, blind to participant and task, using the Analysis of Swallowing Physiology: Events, Kinematics and Timing (ASPEKT) Method. Reference percentiles (p2.5, 5, 25, 50, 75, 95, and 97.5) were determined as per Clinical and Laboratory Standards Institute EP28-A3c guidelines.

RESULTS

We present VFSS reference percentile tables, by consistency, for (a) timing parameters (swallow reaction time; the hyoid burst-to-upper esophageal sphincter (UES)-opening interval; UES opening duration; time-to-laryngeal vestibule closure (LVC); and LVC duration) and (b) anatomically scaled pixel-based measures of maximum UES diameter, pharyngeal area at maximum pharyngeal constriction and rest, residue (vallecular, pyriform, other pharyngeal locations, total), and hyoid kinematics (X, Y, XY coordinates of peak position; speed). Clinical decision limits are proposed to demarcate atypical values of potential clinical concern.

CONCLUSION

These updated reference percentiles and proposed clinical decision limits are intended to support interpretation and reliability for VFSS assessment data.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24043041.

Exploring the Efficacy of the Effortful Swallow Maneuver for Improving Swallowing in People With Parkinson Disease-A Pilot Study

Objectives

To determine the immediate (compensatory) and longer term (rehabilitative) effect of the effortful swallow (ES) maneuver on physiological swallowing parameters in Parkinson disease.

Design

Virtual intervention protocol via Microsoft Teams with pre- and post-videofluoroscopic swallowing studies.

Setting

Outpatient hospital setting, with intervention performed virtually.

Participants

Eight participants (median age 74 years [63-82])with Parkinson disease (years post onset 3-20) with a Hoehn and Yahr scale score between 2 and 4 (N=8).

Interventions

ES maneuver, initiated using a maximum effort isometric tongue-to-palate press, with biofeedback provided using the Iowa Oral Performance Instrument. The protocol included 30 minute sessions twice daily, 5 days/week for 4 weeks.

Main Outcome Measures

Penetration-Aspiration Scale scores, time-to-laryngeal-vestibule-closure, total pharyngeal residue, and pharyngeal area at maximum constriction as seen on lateral view videofluoroscopy.

Results

No consistent, systematic trends were identified in the direction of improvement or deterioration across Penetration-Aspiration Scale scores, time-to-laryngeal-vestibule-closure, pharyngeal area at maximum constriction, or total pharyngeal residue.

Conclusions

Heterogeneous response to the ES as both a compensatory and rehabilitative technique. Positive response on the compensatory probe was predictive of positive response after rehabilitation.

Normative Reference Values for FEES and VASES: Preliminary Data From 39 Nondysphagic, Community-Dwelling Adults

PURPOSE

The aim of this study was to establish preliminary reference values for the Visual Analysis of Swallowing Efficiency and Safety (VASES)-a standardized rating methodology used to evaluate swallowing safety and efficiency for flexible endoscopic evaluation of swallowing (FEES).

METHOD

FEES were completed in nondysphagic, community-dwelling adults using a standardized protocol of 15 swallowing trials that varied by bolus size, consistency, contrast agent, and swallowing instructions. FEES were blindly analyzed using VASES. Primary outcome measures included bolus location at swallow onset, Penetration-Aspiration Scale (PAS) scores, and percentage-based residue ratings for six anatomic landmarks. Secondary outcome measures included sip size, bite size, and number of swallows.

RESULTS

Thirty-nine healthy adults completed the study, yielding an analysis of 584 swallows. Swallows were initiated with the bolus in the pharynx for 41.8% of trials. PAS 1 was the most common score, accounting for 75.3% of trials, followed by PAS 3, which accounted for 18.8% of trials. When residue was present (> 0%), the amount was relatively small across all anatomic landmarks, with median residue ratings of 2.0% (oropharynx), 1.5% (hypopharynx), 3.0% (epiglottis), 3.0% (laryngeal vestibule), and 3.5% (vocal folds). Five events of aspiration were observed, which were characterized by subglottic residue ratings of 1%, 3%, 10%, 24%, and 90%. The average sip size of self-selected volume cup sips of water was 19.8 ml, and the average bite size of a 3.0-g saltine cracker was 1.33 g. Moreover, 78% of the trials in this study protocol (except 90-ml trials) were completed in a single swallow.

DISCUSSION

The results from this study provide preliminary norms for VASES that could be used as a reference when assessing functional swallowing outcomes during FEES. While this is an important first step in establishing norms for FEES and VASES, clinicians and researchers should be mindful that the normative reference values from this study are from a relatively small study sample (N = 39), with most people below the age of 60 years (n = 30). Future research should expand on these norms by including a greater number of people across the age continuum and with greater racial, ethnic, and gender diversity.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.23504325.

Characterizing Swallowing Impairment in a Post-Lung Transplant Population

BACKGROUND

Lung transplant recipients carry significant pre- and post-lung transplant dysphagia risk factors related to altered respiratory-swallow coordination as well as acute injury and decompensation resulting in the acute post-lung transplant recovery period. However, we are only beginning to understand the potential physiological contributors to altered swallowing in this population.

METHOD

A retrospective, cross-sectional, cohort study of post-lung transplant patients was performed. All participants received a modified barium swallow study (MBSS) as part of standard care during their acute hospitalization using the Modified Barium Swallow Impairment Profile (MBSImP) protocol and scoring metric. A combination of MBSImP scores, Penetration-Aspiration Scale (PAS) scores, Functional Oral Intake Scale (FOIS) scores, International Dysphagia Diet Standardization Initiative (IDDSI) scale levels, and the time from lung transplant to MBSS was collected, as well as measures of swallowing impairment and swallowing-related outcomes. Differences in swallowing physiology and swallowing-related outcomes between participants with typical versus atypical PAS were explored.

RESULTS

Forty-two participants met our prespecified inclusion criteria. We identified atypical laryngeal penetration and/or aspiration in 52.4% of our post-lung transplant cohort. Silent aspiration occurred in 75% of those patients who aspirated. Comparing typical versus atypical PAS scores, we found statistically significant associations with laryngeal elevation (Component 8), p < .0001; anterior hyoid excursion (Component 9), p = .0046; epiglottic movement (Component 10), p = .0031; laryngeal vestibule closure (Component 11), p < .0001; pharyngeal stripping (Component 12), p = .0058; pharyngeal total scores, p = .0001; FOIS scores, p = .00264; and IDDSI liquid levels, p = .0009.

CONCLUSIONS

Swallowing impairment resulting in abnormal bolus invasion is prevalent in post-lung transplant patients. Airway invasion in this cohort was related to pharyngeal swallow impairment and resulted in modified oral intake. Our findings help expand upon prior literature, which only reported the incidence of aspiration and pathological laryngeal penetration. Our results suggest that the potential for aerodigestive system impairment and negative sequela should not be underestimated in the post-lung transplant population.

Functional Lingual Pressure Thresholds for Swallowing Safety and Efficiency Impairments in Amyotrophic Lateral Sclerosis

Although reductions in lingual strength are reported in individuals with amyotrophic lateral sclerosis (ALS) that are associated with dysphagia; determination of a functional lingual pressure threshold (FLPT) has not yet been established. The present study therefore sought to identify an FLPT for impaired swallowing safety and efficiency in individuals with ALS.Thirty individuals with ALS completed a standardized videofluoroscopic swallowing examination and maximum anterior isometric lingual pressure testing using the Iowa Oral Performance Instrument. Duplicate, blinded ratings of the validated Penetration-Aspiration Scale (PAS) scores and Analysis of Swallowing Physiology: Events, Kinematics and Timing (ASPEKT) were performed. Binary classifications of safety (unsafe: PAS: ≥ 3) and efficiency (inefficient: ≥ 3% worst total pharyngeal residue) were derived. Descriptives and receiver operating characteristic curve analyses (AUC, sensitivity, specificity) were performed.Unsafe and inefficient swallowing were instrumentally confirmed in 57% and 70% of ALS patients, respectively. Across the entire cohort, the mean maximum lingual physiologic capacity was 32.1 kilopascals ('kPa'; SD: 18.1 kPa). The identified FLPT for radiographically confirmed unsafe swallowing was 43 kPa (sensitivity: 94%, specificity: 62%, AUC 0.82, p = 0.003). FLPT for inefficient swallowing was 46 kPa (sensitivity: 86%, specificity: 56%, AUC = 0.77, p = 0.02).These data provide preliminary FLPT data in a small cohort of individuals with ALS that need to be further investigated in larger cohorts to inform clinical screening practices.

Maximum lingual pressure impacts both swallowing safety and efficiency in individuals with amyotrophic lateral sclerosis

BACKGROUND

Although reduced lingual strength is a confirmed early manifestation of amyotrophic lateral sclerosis (ALS), its functional impact on swallowing remains unclear. We therefore sought to examine relationships between maximum anterior isometric lingual pressure (MAIP) with swallowing safety, swallowing efficiency, and swallowing timing metrics in a large cohort of individuals with ALS.

METHODS

Ninety-seven participants with ALS completed a standardized videofluoroscopic swallowing examination (VF) and lingual pressure testing (Iowa Oral Performance Instrument). Duplicate and blinded ratings of the Penetration-Aspiration Scale (PAS) and Analysis of Swallowing Physiology: Events, Kinematics and Timing (ASPEKT) percent efficiency (%C2-C42 ) and timing (laryngeal vestibule closure (LVC) duration: amount of time (milliseconds, msec) between LVC onset and laryngeal vestibule opening; time-to-LVC: hyoid burst to onset of LVC (msec); and swallow reaction time: interval between bolus passing ramus of mandible and onset of LVC (msec)) were performed across bolus trials. Swallowing safety (safe PAS: 1, 2, 4; unsafe PAS: 3, 5, 6, 7, and 8) and efficiency (inefficient: ≥3% worst total residue) were derived. Statistical analyses including descriptives, binary logistic regressions, and Spearman's rho correlations were performed (α = 0.05).

KEY RESULTS

Mean MAIP was 36.3 kPa (SD: 18.7). Mean MAIP was higher in those with safe swallowing as compared to those who penetrated (mean difference: 12 kPa) or aspirated (mean difference: 18 kPa). Individuals with efficient swallowing demonstrated higher MAIP than those with inefficient swallowing (mean difference: 11 kPa). Binary logistic regression analyses revealed increasing MAIP was significantly associated with a 1.06 (95% CI: 1.03-1.09) and 1.04 (95% CI: 1.01-1.06) greater odds of safe and efficient swallowing, respectively. No relationships were observed between MAIP and swallow reaction time across all bolus trials. Longer time-to-LVC (5 ml thin liquid: rs  = -0.35, p = 0.002; cup sip thin liquid: rs  = -0.26, p = 0.02; moderately thick liquid: rs  = -0.28, p = 0.01) and prolonged LVC duration (cup sip thin liquid, rs  = -0.34, p = 0.003) were associated with lower MAIP.

CONCLUSIONS AND INFERENCES

Reduced lingual strength was confirmed in this group of 97 individuals with ALS that was associated with a diminished ability to effectively transport boluses and aide in laryngeal vestibule closure to prevent entry of material into the airway.

Swallowing Problems in Spinal Muscular Atrophy Types 2 and 3: A Clinical, Videofluoroscopic and Ultrasound Study

Background: Spinal muscular atrophy (SMA) is a hereditary motor neuron disorder, characterized by the degeneration of motor neurons and progressive muscle weakness. There is a large variability of disease severity, reflected by the classification of SMA types 1–4. Objective: The aim of this cross-sectional study was to determine the nature of swallowing problems and underlying mechanisms in patients with SMA types 2 and 3, and the relationship between swallowing and mastication problems. Methods: We enrolled patients (aged 13–67 years) with self-reported swallowing and/or mastication problems. We used a questionnaire, the functional oral intake scale, clinical tests (dysphagia limit, and timed test swallowing, the test of mastication and swallowing solids), a videofluoroscopic swallowing study (VFSS), and muscle ultrasound of the bulbar muscles (i.e. digastric, geniohyoid and tongue muscles). Results: Non-ambulant patients (n = 24) had a reduced dysphagia limit (median 13 ml (3–45), and a swallowing rate at the limit of normal (median 10 ml/sec (range 4–25 ml). VFSS revealed piecemeal deglutition and hypo-pharyngeal residue. We found pharyngo-oral regurgitation in fourteen patients (58%), i.e. they transported the residue from the hypopharynx back into the oral cavity and re-swallowed it. Six patients (25%) demonstrated impaired swallowing safety (i.e. PAS >3). Muscle ultrasound revealed an abnormal muscle structure of the submental and tongue muscles. Ambulant patients (n = 3), had a normal dysphagia limit and swallowing rate, but VFSS showed hypo-pharyngeal residue, and muscle ultrasound demonstrated an abnormal echogenicity of the tongue. Swallowing problems were associated with mastication problems (p = 0.001).

Using Reference Values to Identify Profiles of Swallowing Impairment in a Case Series of Individuals With Traumatic Spinal Cord Injury

PURPOSE

In this article, we illustrate use of a systematic approach to rating videofluoroscopic swallowing studies (VFSS), the Analysis of Swallowing Physiology: Events, Kinematics and Timing (ASPEKT) method. The method is applied to a clinical case series of individuals with a history of traumatic spinal cord injury (tSCI) requiring surgical intervention using a posterior approach. Previous studies suggest that swallowing is highly variable in this population given heterogeneity in mechanisms, location and extent of injury, and in surgical management approaches.

METHOD

The case series involved 6 individuals who were at least 1 month postsurgery for management of tSCI. Participants completed a VFSS using a standardized bolus protocol. Each VFSS was blindly rated in duplicate using the ASPEKT method and compared with published reference values.

RESULTS

The analysis revealed considerable heterogeneity across this clinical sample. Penetration-aspiration scale scores of 3 or higher were not observed in this cohort. Of note, patterns of impairment did emerge, suggesting there are some commonalities across profiles in this population, including the presence of residue associated with poor pharyngeal constriction, reduced upper esophageal opening diameter, and short upper esophageal sphincter opening duration.

CONCLUSIONS

Although the participants in this clinical sample shared a history of tSCI requiring surgical intervention using a posterior approach, there was great heterogeneity in swallowing profile. Using a systematic method to identify atypical swallowing parameters can guide clinical decision making for determining rehabilitative targets and measuring swallowing outcomes.

The Influence of Sex, Age, and Repeated Measurement on Pixel-Based Measures of Pharyngeal Area at Rest

PURPOSE

Videofluoroscopic (VFSS) measurements of pharyngeal swallow mechanics can differentiate age- and disease-related changes in swallowing. Pharyngeal area at rest (PhAR) may differ in people with dysphagia, although its impact is not clear. Before the role of PhAR in dysphagia can be explored, it is important to establish whether PhAR remains stable across repeated measures in healthy adults, and varies as a function of sex or age. We hypothesized that healthy adults would show stable PhAR across repeated measures, but that larger PhAR would be seen in men versus women and in older versus younger adults.

METHOD

We collected VFSS data from 87 healthy adults (44 men, M age = 46 years, range: 21-82). Trained raters identified the swallow rest frame after the initial swallow of each bolus and measured unobliterated pharyngeal area on these frames, in %(C2-4)2 units. Repeated-measures analyses of variance with a factor of sex, a covariate of age, and a repeated factor of task repetition were performed across the first 12 available measures per participant (N = 1,044 swallows).

RESULTS

There were no significant variations in PhAR across repeated measures. A significant Sex × Age interaction was seen (p = .04): Males had significantly larger PhAR than females (p = .001), but females showed larger PhAR with advancing age (R = .47).

CONCLUSIONS

These data confirm stability in PhAR across repeated measurements in healthy individuals. However, significant sex and age differences should be taken into consideration in future studies exploring the role of PhAR in people with dysphagia.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.22043543.

Quantifying Pharyngeal Residue Across the Adult Life Span: Normative Values by Age, Gender, and Swallow Task

PURPOSE

We quantified pharyngeal residue using pixel-based methods in a normative data set, while examining influences of age, gender, and swallow task.

METHOD

One hundred ninety-five healthy participants underwent a videofluoroscopic swallow study following the Modified Barium Swallow Impairment Profile (MBSImP) protocol. ImageJ was used to compute Normalized Residue Ratio Scale and the Analysis of Swallowing Physiology: Events, Kinematics and Timing (ASPEKT) pharyngeal residue measures. Reliability was established. Descriptive statistics were performed for all residue measures. Inferential statistics were performed using ASPEKT total scores (i.e., %C2-42). Logistic regression models explored predictors of residue versus no residue. Generalized linear mixed models explored predictors of nonzero residue. Spearman rho explored relationships between ASPEKT total residue scores and MBSImP Component 16 (Pharyngeal Residue) scores.

RESULTS

Majority of swallows (1,165/1,528; 76.2%) had residue scores of zero. Residue presence (%C2-42 > 0) was influenced by age (more in older [F = 9.908, p = .002]), gender (more in males [F = 18.70, p < .001]), viscosity (more in pudding, nectar, and honey [F = 25.30, p < .001]), and volume (more for cup sip [F = 37.430, p < .001]). When residue was present (363/1,528 = 23.8%), amounts were low (M = 1% of C2-42, SD = 2.4), and only increasing age was associated with increased residue (F = 9.008, p = .007) when controlling for gender and swallow task. Increasing residue was incremental (0.01% of C2-42 per year). As ASPEKT total residue values increased, MBSImP Component 16 scores also increased.

CONCLUSIONS

Pharyngeal residue amounts were very low in healthy adults. Residue presence can be influenced by age, gender, and swallow task. However, when present, the amount of pharyngeal residue was only associated with increasing age.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21957221.

Temporal Sequence of Laryngeal Vestibule Closure and Reopening is Associated With Airway Protection

BACKGROUND

Upper esophageal sphincter opening (UESO), and laryngeal vestibule closure (LVC) are two essential kinematic events whose timings are crucial for adequate bolus clearance and airway protection during swallowing. Their temporal characteristics can be quantified through time-consuming analysis of videofluoroscopic swallow studies (VFSS).

OBJECTIVES

We sought to establish a model to predict the odds of penetration or aspiration during swallowing based on 15 temporal factors of UES and laryngeal vestibule kinematics.

METHODS

Manual temporal measurements and ratings of penetration and aspiration were conducted on a videofluoroscopic dataset of 408 swallows from 99 patients. A generalized estimating equation model was deployed to analyze association between individual factors and the risk of penetration or aspiration.

RESULTS

The results indicated that the latencies of laryngeal vestibular events and the time lapse between UESO onset and LVC were highly related to penetration or aspiration. The predictive model incorporating patient demographics and bolus presentation showed that delayed LVC by 0.1 s or delayed LVO by 1% of the swallow duration (average 0.018 s) was associated with a 17.19% and 2.68% increase in odds of airway invasion, respectively.

CONCLUSION

This predictive model provides insight into kinematic factors that underscore the interaction between the intricate timing of laryngeal kinematics and airway protection. Recent investigation in automatic noninvasive or videofluoroscopic detection of laryngeal kinematics would provide clinicians access to objective measurements not commonly quantified in VFSS. Consequently, the temporal and sequential understanding of these kinematics may interpret such measurements to an estimation of the risk of aspiration or penetration which would give rise to rapid computer-assisted dysphagia diagnosis.

LEVEL OF EVIDENCE

2 Laryngoscope, 133:521-527, 2023.

Swallowing analysis in hemi-tongue reconstruction using motor-innervated free flaps: A cine-magnetic resonance imaging study

BACKGROUND

This study aimed to explore the outcomes of motor-innervated free flaps in hemi-tongue reconstruction by assessing the tongue mobility through midsagittal images from cine-magnetic resonance imaging.

METHODS

In this retrospective study, 47 patients who underwent tongue reconstruction following hemi-glossectomy and 10 control subjects without any surgical history were included. Patients were classified into two groups: the motor and no-motor innervation group. Various spatial parameters related to tongue mobility that were acquired from midsagittal sections were compared during consecutive swallowing phases.

RESULTS

Overall, the motor group showed improved functional swallowing scale compared with the no-motor group. In case of tongue base resection, the motor group showed improved mobility of the tongue base during pharyngeal phase, whereas the no-motor group showed increased laryngeal elevation for compensatory movement.

CONCLUSION

The tongue reconstruction with motor-innervated free flaps may facilitate swallowing capacity in patients with a hemi-tongue defect combined with tongue base resection.

Pixel-Based Swallow Measurements: Correcting Nonsquare Pixels

PURPOSE

This research note illustrates the effects of video data with nonsquare pixels on the pixel-based measures obtained from videofluoroscopic swallow studies (VFSS).

METHOD

Six pixel-based distance and area measures were obtained from two different videoflouroscopic study units; both yielding videos with nonsquare pixels with different pixel aspect ratios (PARs). The swallowing measures were obtained from the original VFSS videos and from the videos after their pixels were squared.

RESULTS

The results demonstrated significant multivariate effects both in video type (original vs. squared) and in the interaction between video type and sample (two video recordings of different patients, different PARs, and opposing tilt angles of the external reference). A wide range of variabilities was observed on the pixel-based measures between original and squared videos with the percent deviation ranging from 0.1% to 9.1% with the maximum effect size of 7.43.

CONCLUSIONS

This research note demonstrates the effect of disregarding PAR to distance and area pixel-based parameters. In addition, we present a multilevel roadmap to prevent possible measurement errors that could occur. At the planning stage, the PAR of video source should be identified, and, at the analyses stage, video data should be prescaled prior to analysis with PAR-unaware software. No methodology in prior absolute or relative pixel-based studies reports adjustment to the PAR prior to measurements nor identify the PAR as a possible source of variation within the literature. Addressing PAR will improve the precision and stability of pixel-based VFSS findings and improve comparability within and across clinical and research settings.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21957134.

Differences in pharyngeal swallow event timing: Healthy aging, Parkinson disease, and amyotrophic lateral sclerosis

Objective

The pharyngeal phase of swallowing involves a coordinated sequence of events. Event durations may be prolonged in people with Parkinson disease (PwPD), and amyotrophic lateral sclerosis (PwALS); however, the cumulative effect of these changes is unexplored. We compared event latencies relative to hyoid burst (HYB) (time zero) to understand differences in deglutatory event timing. We hypothesized PwPD and PwALS would display similarly prolonged cumulative pharyngeal phase durations compared to healthy controls, with greater prolongations with increasing bolus viscosity.

Method

We retrospectively evaluated videofluoroscopic data of healthy adults (n = 78), PwPD (n = 17), and PwALS (n = 20). Participants swallowed 15 boluses of 20% (w/v) barium across five liquid consistencies. Paired raters evaluated nine deglutitive events using the ASPEKT method. Latencies were plotted by consistency relative to HYB and compared across cohorts using Mann-Whitney U tests (p ≤ .05). Cohen's d was calculated for all statistically significant results to determine effect size.

Results

In PwPD, significantly prolonged latencies were observed on thin liquid boluses compared to healthy controls. Latencies to all post-HYB events were significantly prolonged except for maximum upper esophageal sphincter distension. In PwALS, significantly prolonged latencies for events preceding and following HYB were noted on all consistencies compared to healthy controls and PwPD.

Conclusion

In PwPD, event latencies for multiple components of the swallowing sequence were prolonged culminating in overall prolongation of the pharyngeal phase on thin liquid. A similar pattern, but with significantly greater prolongation, was seen in the PwALS, and extended to swallows of all liquid consistencies.

Videofluoroscopy Practice in India: A Survey of Speech-Language Pathologists

Owing to differences in clinical approaches toward videofluoroscopic swallowing studies (VFSS), professional and governing bodies in some countries have implemented guidelines for performing VFSS. However, in India, the establishment of such practice guidelines is in initial stages of acceptance and there are no uniform guidelines. The aim of the current study was to investigate and describe the clinical practice patterns related to VFSS assessments among Speech-Language Pathologists (SLPs) in India. An electronic survey consisting of 34 questions categorized into four main sections (demographic details and education; current practice; instrumental and technical considerations; protocol and assessment methods) was sent to SLPs registered with the Indian Speech and Hearing Association (ISHA) through email and social media from August 2020 to January 2021. A total of 129 eligible responses were received. More than 50% of the participants used a standard assessment and analysis protocol. Barium and water-soluble contrasts were mostly used, and 97% of participants did not know what percent weight to volume (w/v) or volume to volume (v/v) contrast to fluid were used. Considerable amount of variability was observed in the responses of our participants, which was consistent with international surveys of VFSS practice patterns. Lack of adequate radiation safety measures was also observed. Our findings suggest a need to increase awareness and training among Indian SLPs in technical and procedural aspects of VFSS, and more sensitization toward radiation safety. ISHA should consider forming a committee to develop and adopt uniform nationwide practices in VFSS. Future studies exclusively investigating barriers and facilitators to VFSS practice in the Indian scenario are necessary.

The Effect of Swallowing Cues in Healthy Individuals: An Exploratory Study

The goal of this study was to determine whether providing verbal and visual cues about swallowing changes the timing of swallowing events, and whether this information interacts with bolus volume. 20 healthy adults swallowed 5 ml and 15 ml liquid barium mixed with orange juice under videofluoroscopy during 2 conditions: one condition absent swallowing-specific cues and one condition with verbal and visual input about the swallowing process. Outcome measures included the timing of 10 swallowing events and the number of swallows per bolus. As expected, volume had a significant effect on all outcome measures (p < 0.05). Three timing events differed by cueing condition: 1. swallowing reaction time was earlier for control (- 9.45 ms vs. - 2.01 ms, p = 0.033); 2. the time between initial hyoid movement and maximum hyoid elevation was longer for control (152.85 ms vs. 143.79 ms; p = 0.015); and 3. the onset of upper esophageal sphincter opening occurred later after bolus entry into the pharynx for the swallowing cues condition (111.9 ms vs. 103.31 ms; p = 0.017); however, effect sizes were small (< 0.2). There was a significant interaction between cue condition and bolus volume on swallowing frequency, such that the mean number of swallows of 15 ml boluses was slightly higher during the control condition than during the swallowing cues condition. There were no significant interactions on measures of timing, suggesting distinct mechanisms for the effect of bolus volume and cues on swallowing kinematics. Further research is needed to investigate the effects of different cue modalities and focus (internal vs. external) on swallowing physiology.

Dysphagia Presentation, Airway Invasion, and Gender Differences in a Clinically Based Sample of People with Parkinson's Disease

Dysphagia in People with Parkinson's Disease (PWPD) is expected to occur in most individuals. The manifestation of dysphagia and its salient swallow dysfunction characteristics leading to decreased airway safety are not well understood. The aim of this study was to quantify dysphagia presentation and severity, examine contributors to airway invasion, and explore gender differences in dysphagia manifestation in PWPD. 60 PWPD in clinical, healthcare settings underwent a Videofluoroscopic Swallow Study (VFSS) after referral for complaints of dysphagia. VFSS records and videos were analyzed to obtain dysphagia diagnosis, Videofluoroscopic Dysphagia Scale (VDS) scores, laryngeal vestibule kinematic timings, and Penetration-Aspiration Scale scores. Frequencies of VDS component and PAS scores were examined. MANOVA and logistic regression analyses were used to identify predictors of penetration and aspiration. Pharyngeal stage dysphagia was prevalent throughout PWPD and presented more frequently than oral stage dysphagia. Pharyngeal residue was a significant predictor for aspiration events. Laryngeal vestibule closure reaction time (LVCrt) and duration time (LVCd) were significant predictors of airway invasion, as were bolus consistency and volume. LVCrt, LVCd, and pharyngeal stage VDS scores were significantly altered in men compared to women in PWPD. A broad clinical sample of PWPD displayed atypical frequencies of airway invasion and frequent atypical scores of oral and pharyngeal stage physiologies. Thicker and smaller bolus consistencies significantly reduced the odds of airway invasion. Men and women presented with significantly different swallow physiology including prolonged LVCrt, LVCd, and more frequent atypical scores of pharyngeal residue and laryngeal elevation.Journal instruction requires a country for affiliations; however, these are missing in affiliation [1, 2]. Please verify if the provided country are correct and amend if necessary.Yes, USA is correct as the provided country.

Dysphagia after cardiac surgery: Prevalence, risk factors, and associated outcomes

OBJECTIVES

The study objectives were to determine the prevalence of swallowing impairment in adults after cardiac surgery and examine associated risk factors and health-related outcomes.

METHODS

A prospective single-center study was conducted in postoperative adult cardiac surgery patients with no history of dysphagia. A standardized fiberoptic endoscopic evaluation of swallowing was performed within 72 hours of extubation. Blinded raters completed validated outcomes of swallowing safety and efficiency. Demographic, surgical, and postoperative health-related outcomes were collected. Univariate and multivariable regression analyses were performed with odds ratios (OR) and 95% confidence intervals (CIs).

RESULTS

In 182 patients examined, imaging confirmed inefficient swallowing (residue) in 52% of patients and unsafe swallowing in 94% (65% penetrators, 29% aspirators). Silent aspiration was observed in 53% of aspirators, and 32% did not clear aspirate material. Independent risk factors for aspiration included New York Heart Association III and IV (OR, 2.9; CI, 1.2-7.0); reoperation (OR, 2.0; CI, 0.7-5.5); transesophageal echocardiogram images greater than 110 (OR, 2.6; CI, 1.1-6.3); intubation greater than 27 hours (OR, 2.1; CI, 0.8-5.3); and endotracheal tube size 8.0 or greater (OR, 3.1; CI, 1.1-8.6). Patients with 3 or 4 identified risk factors had a 16.4 (CI, 3.2-148.4) and 22.4 (CI, 3.7-244.7) increased odds of aspiration, respectively. Compared with nonaspirators, aspirators waited an additional 85 hours to resume oral intake, incurred $49,372 increased costs, and experienced a 43% longer hospital stay (P < .05). Aspiration was associated with pneumonia (OR, 2.6; CI, 1.1-6.5), reintubation (OR, 5.7; CI, 2.1-14.0), and death (OR, 2.8; CI, 1.2-9.0).

CONCLUSIONS

Tracheal aspiration was prevalent, covert, and associated with increased morbidity and mortality.

Profiles of Dysarthria and Dysphagia in Individuals With Amyotrophic Lateral Sclerosis

PURPOSE

While dysarthria and dysphagia are known bulbar manifestations of amyotrophic lateral sclerosis (ALS), the relative prevalence of speech and swallowing impairments and whether these bulbar symptoms emerge at the same time point or progress at similar rates is not yet clear. We, therefore, sought to determine the relative prevalence of speech and swallowing impairments in a cohort of individuals with ALS and to determine the impact of disease duration, severity, and onset type on bulbar impairments.

METHOD

Eighty-eight individuals with a confirmed diagnosis of ALS completed the ALS Functional Rating Scale-Revised (ALSFRS-R), underwent videofluoroscopy (VF), and completed the Sentence Intelligibility Test (SIT) during a single visit. Demographic variables including disease duration and onset type were also obtained from participants. Duplicate, independent, and blinded ratings were completed using the Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scale and SIT to index dysphagia (DIGEST ≥ 1) and dysarthria (< 96% intelligible and/or < 150 words per minute) status. Descriptive statistics, Pearson chi-squared tests, independent-samples t tests, and odds ratios were performed.

RESULTS

Dysphagia and dysarthria were instrumentally confirmed in 68% and 78% of individuals with ALS, respectively. Dysarthria and dysphagia were associated (p = .01), and bulbar impairment profile distributions in rank order included (a) dysphagia - dysarthria (59%, n = 52), (b) no dysphagia - dysarthria (19%, n = 17), (c) no dysphagia - no dysarthria (13%, n = 11), and (d) dysphagia - no dysarthria (9%, n = 8). Participants with dysphagia or dysarthria demonstrated 4.2 higher odds of exhibiting a bulbar impairment in the other domain than participants with normal speech and swallowing (95% CI [1.5, 12.2]). There were no differences in ALSFRS-R total scores or disease duration across bulbar impairment profiles (p > .05). ALSFRS-R bulbar subscale scores were significantly lower in individuals with dysphagia versus no dysphagia (8.4 vs. 10.4, p < .0001) and dysarthria versus no dysarthria (8.5 vs. 10.9, p < .0001). Dysphagia and onset type (p = .003) and dysarthria and onset type were associated (p < .0001).

CONCLUSIONS

Over half of the individuals with ALS in this study demonstrated both dysphagia and dysarthria. Of those with only one bulbar impairment, speech was twice as likely to be the first bulbar symptom to degrade. Future studies are needed to confirm these findings and determine the longitudinal progression of bulbar impairments in this patient population.

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 < 65 mmHg (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) < 55 mmHg·cm·s [OR 2.30; 95% CI (1.07-4.96); p = 0.034]. Pyriform sinus residue was independently predicted by HypoPeakP < 65 mmHg [OR 7.32; 95% CI (1.93-27.7); p = 0.003], UES integrated relaxation pressure (UES-IRP) > 3 mmHg [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.

The Feasibility of Home-Based Treatment Using Vibratory Stimulation in Chronic Severe Dysphagia

PURPOSE

Previously, externally placed vibratory laryngeal stimulation increased rates of swallowing in persons with and without dysphagia. This study examined the feasibility of using a vibratory device on the skin over the thyroid cartilage for home-based swallowing rehabilitation in long-standing dysphagia.

METHOD

Only participants with long-standing dysphagia (> 6 months) following cerebrovascular accident or head/neck cancer who had not previously benefited from dysphagia therapy participated. The device had two modes used daily for 90 days. In automatic mode, participants wore the device when awake, which vibrated for 4-8 s every 5 min to trigger a volitional swallow. In manual mode, participants practiced by activating vibration while swallowing rapidly. Study-related adverse events, such as pneumonia, and device-recorded adherence were tracked. Swallowing function on a modified barium swallow study was assessed at baseline and after 3 months of device use. Outcome measures included the Dysphagia Outcome and Severity Scale (DOSS), Penetration-Aspiration Scale (PAS), and swallowing timing measures. Participants' perceptions of the vibratory device and training were obtained.

RESULTS

The intent to treat analysis showed seven of 11 participants completed the study, all with severe chronic dysphagia. Of those seven participants completing the study, two developed respiratory complications (possibly due to pneumonia) that cleared after antibiotic intervention. For prescribed practice trials, adherence was 80% or greater in four of seven participants (57%) whereas prescribed automatic stimulations were met in only two of seven participants (29%). Three participants (43%) had a modest benefit on DOSS. The time to vestibule closure after the bolus passed the ramus was reduced in five participants (71%) on the modified barium swallow study.

CONCLUSION

Overall, the results have indicated that intensive home-based practice with stimulation may provide limited functional benefits in severe chronic dysphagia.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21498591.

Effects of Food and Liquid Properties on Swallowing Physiology and Function in Adults

Foods and liquids have properties that are often modified as part of clinical dysphagia management to promote safe and efficient swallowing. However, recent studies have questioned whether this practice is supported by the evidence. To address this, a scoping review was conducted to answer the question: "Can properties of food and liquids modify swallowing physiology and function in adults?" Online search in six databases yielded a set of 4235 non-duplicate articles. Using COVIDENCE software, two independent reviewers screened the articles by title and abstract, and 229 full-text articles were selected for full-text review. One-hundred eleven studies met the inclusion criteria for qualitative synthesis and assessment of risk of bias. Three randomized controlled trials and 108 non-randomized studies were analyzed. Large amounts of variability in instrumental assessment, properties of food and liquids, and swallowing measures were found across studies. Sour, sweet, and salty taste, odor, carbonation, capsaicin, viscosity, hardness, adhesiveness, and cohesiveness were reported to modify the oral and pharyngeal phase of swallowing in both healthy participants and patients with dysphagia. Main swallow measures modified by properties of food and liquids were penetration/aspiration, oral transit time, lingual pressures, submental muscle contraction, oral and pharyngeal residue, hyoid and laryngeal movement, pharyngeal and upper esophageal sphincter pressures, and total swallow duration. The evidence pooled in this review supports the clinical practice of food texture and liquid consistency modification in the management of dysphagia with the caveat that all clinical endeavors must be undertaken with a clear rationale and patient-specific evidence that modifying food or liquid benefits swallow safety and efficiency while maintaining quality of life.

Automated pharyngeal phase detection and bolus localization in videofluoroscopic swallowing study: Killing two birds with one stone?

BACKGROUND AND OBJECTIVE

The videofluoroscopic swallowing study (VFSS) is a gold-standard imaging technique for assessing swallowing, but analysis and rating of VFSS recordings is time consuming and requires specialized training and expertise. Researchers have recently demonstrated that it is possible to automatically detect the pharyngeal phase of swallowing and to localize the bolus in VFSS recordings via computer vision approaches, fostering the development of novel techniques for automatic VFSS analysis. However, training of algorithms to perform these tasks requires large amounts of annotated data that are seldom available. In this paper, we demonstrate that the challenges of pharyngeal phase detection and bolus localization can be solved together using a single approach.

METHODS

We propose a deep-learning framework that jointly tackles pharyngeal phase detection and bolus localization in a weakly-supervised manner, requiring only the initial and final frames of the pharyngeal phase as ground truth annotations for the training. Our approach stems from the observation that bolus presence in the pharynx is the most prominent visual feature upon which to infer whether individual VFSS frames belong to the pharyngeal phase. We conducted extensive experiments with multiple convolutional neural networks (CNNs) on a dataset of 1245 bolus-level clips from 59 healthy subjects.

RESULTS

We demonstrated that the pharyngeal phase can be detected with an F1-score higher than 0.9. Moreover, by processing the class activation maps of the CNNs, we were able to localize the bolus with promising results, obtaining correlations with ground truth trajectories higher than 0.9, without any manual annotations of bolus location used for training purposes.

CONCLUSIONS

Once validated on a larger sample of participants with swallowing disorders, our framework will pave the way for the development of intelligent tools for VFSS analysis to support clinicians in swallowing assessment.

Which Videofluoroscopy Parameters Are Susceptible to the Influence of Differences in Barium Product and Concentration?

PURPOSE

Prior studies suggest there may be differences in videofluoroscopic measures of swallowing across different barium concentrations. Whether different barium products of identical concentration result in similar swallowing physiology remains unknown. This is important, as barium intended for videofluoroscopy (i.e., Bracco Varibar) is not available globally. Our aim was to identify differences in healthy swallowing across five different barium stimuli.

METHOD

Twenty healthy adults (10 women), aged 22-54 years, underwent videofluoroscopy including comfortable sips of thin liquid barium: two sips of 20% weight-to-volume (w/v) barium prepared with E-Z-HD powder, and two sips each of 20%w/v and 40%w/v barium prepared with Liquid Polibar Plus and E-Z-Paque powder. Recordings were analyzed according to the Analysis of Swallowing Physiology: Events, Kinematics and Timing Method. Measures of timing, kinematics and residue were obtained. Chi-square, Friedman's, and Wilcoxon signed-ranks test were used to identify differences across stimuli.

RESULTS

Significant differences were seen across barium stimuli for upper esophageal sphincter (UES) opening duration, UES diameter, pharyngeal area at maximum constriction, and residue. In all cases, smaller values were seen with the 20%w/v E-Z-HD stimulus; however, this stimulus had questionable opacity for visualization. Patterns of residue severity were not explained by barium concentration.

CONCLUSIONS

This study confirms that some measures of swallowing are influenced by barium product and/or concentration. Measures are not necessarily similar across different barium products at the same concentration. This study illustrates the importance of using standard and appropriate stimuli in videofluoroscopy, and for clinicians to report not only the product but also the concentration of stimuli used.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.20669712.

Swallow Safety and Laryngeal Kinematics: A Comparison of Dysphagia Between Parkinson's Disease and Cerebrovascular Accident

BACKGROUND

Cerebrovascular accident (CVA) and Parkinson's disease (PD) are well established etiologies of dysphagia. However, differing physiological mechanisms underlying dysphagia may exist between these two causes. There have been limited investigations specifically comparing dysphagia between these two groups. Comparing dysphagia presentation in two different populations may improve clinical expectations, guide treatment approaches, and inform future research.

OBJECTIVE

This study examined the differences in presentation of dysphagia between PD and CVA. Dysphagia presentation, swallow safety, and laryngeal kinematics were compared between two clinical cohorts. What factors best predicted airway invasion in each group were explored.

METHODS

110 swallow studies of individuals with PD and CVA who were referred for swallowing evaluation were obtained. Each video was analyzed for quantitative dysphagia presentation using the Videofluoroscopic Dysphagia Scale (VDS), swallow safety using the Penetration-Aspiration scale, and kinematic timings of the laryngeal vestibule (time-to-laryngeal vestibule closure [LVC] and closure duration [LVCd]).

RESULTS

Frequencies of penetration or aspiration were similar between groups. The PD group displayed significantly greater pharyngeal stage swallow impairment than CVA, with more frequent reduced laryngeal elevation and increased vallecular residue. The CVA group displayed significantly greater oral stage impairment, with prolonged oral transit times. Time-to-LVC was significantly prolonged and was the strongest predictor of airway invasion in the PD group, but not for CVA.

CONCLUSION

Similar airway invasion rates for PD and CVA indicate the importance of screening for dysphagia in PD. Laryngeal kinematics as significant contributors to airway invasion in PD but not for CVA highlight the need for further research into these mechanisms and for targeted treatment approaches to dysphagia.

Comparison of Validated Videofluoroscopic Outcomes of Pharyngeal Residue: Concordance Between a Perceptual, Ordinal, and Bolus-Based Rating Scale and a Normalized Pixel-Based Quantitative Outcome

PURPOSE

This study compared the concordance between two validated videofluoroscopic pharyngeal residue outcome scales used in clinical and research settings: the Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) and the Analysis of Swallowing Physiology: Events, Kinematics and Timing (ASPEKT) percent residue metric.

METHOD

Two trained raters completed independent and blinded videofluoroscopic ratings of both DIGEST efficiency and ASPEKT percent pharyngeal residue outcomes for bolus trials of 5 cc Varibar thin liquid (n = 223), thin liquid comfortable cup sips (n = 223), and 5 cc Varibar thin honey (n = 223). Spearman's rho and Kruskal-Wallis analyses were performed for each bolus type.

RESULTS

Significant associations between DIGEST and ASPEKT pharyngeal residue outcomes were noted for 5 cc thin (r = .54, p < .001), cup sip thin (r = .41, p < .001), and 5 cc thin honey (r = .60, p < .001) bolus trials. ASPEKT percent residue increased across worsening DIGEST efficiency ordinal scale levels, with a main effect for each bolus type. Post hoc analysis revealed significant differences in the ASPEKT percent residue values between each DIGEST pairwise comparison for the thin cup sip bolus trial and for each pairwise comparison except between the moderate-to-severe (less than half vs. majority) ordinal levels for the 5 cc thin and 5 cc honey bolus trials, p < .05.

CONCLUSIONS

Perceptual, ordinal (DIGEST) and quantitative, pixel-based (ASPEKT) videofluoroscopic pharyngeal residue outcomes were associated in this data set of 669 bolus trials. Future research is warranted to confirm these results.