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.

Validation of the IDDSI funnel for liquid flow testing.

In 2017, the International Dysphagia Diet Standardisation Initiative (IDDSI) introduced the IDDSI flow test which enables patients, clinicians, caregivers, food service professionals and researchers to classify liquid thickness into five levels based on the volume of liquid remaining in a standard 10 mL slip tip syringe after 10 s of flow under gravity. Within a few months of publishing the IDDSI flow test instructions, several barriers emerged: (1) the preferred model of syringe (BD 303134) was not equally accessible around the world, causing some users to perform flow tests with alternate models of syringe; (2) differences in syringe geometry across models led to variations in IDDSI flow test results; and (3) the need to use a second syringe for sample loading added complexity and cost to end users. To address these barriers, IDDSI designed the IDDSI funnel, a novel device, which combines the geometry of the BD 303134 syringe with a kitchen funnel to facilitate easy loading of liquid samples without need for a second syringe. In this report, we compare the IDDSI flow test results across two devices: syringe BD 303134 and IDDSI funnel. IDDSI level classifications were in complete agreement with the syringe reference test results in 67/73 (92%) of the test fluids and temperature conditions with mean difference of residual liquid across devices of 0.2 (2% full scale). These results demonstrate excellent correspondence between the two devices.

Tongue Pressure Resistance Training for Post-Stroke Dysphagia: A Case Study.

PURPOSE: The purpose of this study was to explore the effect of a lingual resistance training protocol on the swallowing function of an individual presenting with dysphagia and reduced tongue pressures following a supratentorial ischemic stroke. METHODS: A study involving a lingual resistance training protocol with videofluoroscopy to measure outcomes comparing different parameters to ASPEKT normative reference values at three timepoints: baseline (VFSS A), following a 4-week lead-in period to control for spontaneous recovery (VFSS B), and at the 8-week endpoint of treatment (VFSS C). The study was interrupted due to the COVID-19 pandemic after 1 participant enrollment and is presented as single case study. RESULTS: Isometric tongue pressures: Following the 4-week lead-in, a decline in maximum isometric anterior tongue pressure (MAIP) and regular effort saliva swallow pressures (RESS) was noted, however there was no change in maximum posterior isometric tongue pressures (MPIP). Isometric tongue pressures improved post-treatment, with increases in MAIP, MPIP, and to a lesser degree RESS. Swallowing Function: Impairments in swallowing safety continued between the baseline VFSS A (Penetration-Aspiration Scale score [PAS]=8) and lead-in VFSS B (PAS=5). Swallowing safety improved following the intervention, with PAS scores = 1 at the endpoint VFSS C. Pixel-based measures of swallowing efficiency revealed a reduced frequency of post-swallow total pharyngeal reside following the treatment. Improvements were found in two other swallowing parameters, laryngeal vestibule closure integrity and pharyngeal area at maximum pharyngeal constriction, at the endpoint VFSS. CONCLUSION: These pilot data suggest improvements in some swallowing parameters as an outcome of intervention.

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.

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.

Virtual Accessible Bilingual Conference Planning: The Parks Accessibility Conference.

Virtual events have become more popular recently, and while these events have the potential to be inclusive to a broader range of attendees, there is limited information available on how to plan and deliver a virtual, accessible, and bilingual event. The objective of this paper is to share how our team planned and delivered a virtual conference that was fully bilingual and accessible to individuals with disabilities by incorporating closed captions, sign language interpretation, language interpretation (audio), regularly scheduled breaks, and a multi-sensory experience. We describe our approaches to planning the conference, such as including individuals with disabilities in decision-making, selecting virtual conference platforms, captioners, and interpreters, and how we incorporated a multi-sensory experience. The paper also summarizes feedback we received from our attendees using a post-conference evaluation survey and our team's reflections on positive aspects of the conference and opportunities for improvement. We conclude by providing a set of practical recommendations that we feel may be helpful to others planning virtual accessible bilingual conferences in the future.

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.

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.

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.

Profiles of Swallowing Impairment in a Cohort of Patients With Reduced Tongue Strength Within 3 Months of Cerebral Ischemic Stroke.

PURPOSE: Patients with poststroke dysphagia may experience inefficient bolus clearance or inadequate airway protection. Following a stroke, impairments in lingual pressure generation capacity are thought to contribute to oropharyngeal dysphagia. The goal of our study was to determine whether similar profiles of swallowing impairment would be seen across a cohort of patients with reduced tongue strength within 3 months after cerebral ischemic stroke. METHOD: The sample comprised six adults with reduced tongue strength (i.e., maximum anterior isometric pressure < 40 kPa). Participants underwent a videofluoroscopy according to a standard protocol. Post hoc blinded ratings were completed using the Analysis of Swallowing Physiology: Events, Kinematics and Timing Method and coded as "typical" versus "atypical" (i.e., within vs. outside the healthy interquartile range) in comparison to published reference values. RESULTS: The videofluoroscopies suggested that having reduced tongue strength did not translate into a common profile. Of the six participants, two showed Penetration-Aspiration Scale (PAS) scores of ≥ 3 on thin liquids, associated with incomplete laryngeal vestibule closure (LVC). Another two participants displayed PAS scores of 2 (transient penetration), but these were not associated with incomplete LVC. Pharyngeal residue, above the healthy 75th percentile, was seen for three participants. Five participants presented with atypical reductions in hyoid XY peak position. CONCLUSIONS: In this cohort of adults within 3 months of cerebral ischemic stroke, reductions in tongue strength presented alongside a variety of changes in swallowing physiology. There was no straightforward relationship linking reduced tongue strength to particular patterns of impairment on videofluoroscopy.

Food-Grade Activated Charcoal for Contrast-Enhanced Photoacoustic Imaging of Aspiration: A Phantom Study.

Aspiration pneumonia has the highest attributable mortality of all medical complications post-stroke, or in individuals with progressive neurological diseases. For optimum health outcomes for individuals with dysphagia, a non-invasive and convenient method for objectively detecting aspiration is needed. This study introduces a potential new aspiration screening method based on photoacoustic imaging (PAI), a medical imaging technology that measures the optical contrast of tissue rather than mechanical or elastic properties. In this preliminary study, a tissue-mimicking neck phantom was designed to test the performance of PAI for aspiration screening with a charcoal solution as a contrast agent. A 1064 nm wavelength light source was illuminated on the anterior of the neck phantom to induce the photoacoustic effect. The resulting photoacoustic signal of the charcoal contrast in the mock trachea was detected by a linear transducer array with a 2.25 MHz central ultrasound frequency. The phantom results showed that charcoal solution at 10 mg/ml exhibited strong photoacoustic signals when flowing into the phantom trachea. By overlaying the photoacoustic signals of the charcoal contrast on top of the ultrasound image, we were able to simultaneously visualize the movement of food contrast and a cross-section of tissue structures during mock swallowing. Moreover, we confirmed the ability to detect the flow of charcoal contrast at a small bolus volume of ~ 7 µl through the phantom, suggesting high sensitivity to detect small aspiration events. The study suggests that PAI holds promise to be developed as an aspiration detection tool with charcoal powder as a contrast agent.

Determining the Relationship Between Hyoid Bone Kinematics and Airway Protection in Swallowing.

PURPOSE: Research remains equivocal regarding the links between hyoid movement and penetration-aspiration. The aims of this study were (a) to explore associations between hyoid parameters, laryngeal vestibule closure (LVC) parameters, and penetration-aspiration on thin liquids; and (b) to determine which of these parameters are the strongest predictors of penetration-aspiration. METHOD: This study involved retrospective analysis of an existing videofluoroscopy data set, collected in 305 participants (152 males) with noncongenital/nonsurgical/non-oncological risk for dysphagia. We extracted data for six thin liquid swallows per participant, and obtained measures of hyoid movement (peak position, speed) and LVC (complete/incomplete, timing, duration). Resulting values were coded as typical/atypical relative to healthy reference data. Relationships were explored using chi-square tests and odds ratios (a) for the entire data set and (b) for the subset of data with complete LVC. Hierarchical logistic regression models determined the strongest predictors of penetration-aspiration. RESULTS: Significant associations were found between penetration-aspiration and incomplete LVC, prolonged time-to-most-complete-LVC, short LVC duration, reduced anterior hyoid peak position, and reduced hyoid speed. Hyoid measures were also significantly associated with LVC parameters. In the first regression model, incomplete LVC and prolonged time-to-most-complete-LVC were the only significant predictors of penetration-aspiration. For cases with complete LVC, the only significant predictor was prolonged time-to-most-complete-LVC. CONCLUSIONS: Although reduced anterior hyoid peak position and speed are associated with penetration-aspiration on thin liquids, these measures do not independently account for penetration-aspiration when considered in conjunction with measures of LVC. When identifying mechanisms explaining penetration-aspiration, clinicians should focus on LVC (complete/incomplete) and timeliness of LVC.

Determining the Impact of Thickened Liquids on Swallowing in Patients Undergoing Irradiation for Oropharynx Cancer.

The current standard for the treatment of oropharynx cancers is radiation therapy. However, patients are frequently left with dysphagia characterized by penetration-aspiration (impaired safety) and residue (impaired efficiency). Although thickened liquids are commonly used to manage dysphagia, we lack evidence to guide the modification of liquids for clinical benefit in the head and neck cancer population. The objective of this study was to assess the impact of slightly and mildly thick liquids on penetration-aspiration and residue in 12 patients with oropharyngeal cancer who displayed penetration-aspiration on thin liquid within 3 to 6 months after completion of radiotherapy. Significantly fewer instances of penetration-aspiration were seen with slightly and mildly thick liquids as compared with thin (P < .05). No differences were found across stimuli in the frequency of residue. Patients with oropharyngeal cancers who present with post-radiation therapy dysphagia involving penetration-aspiration on thin liquids may benefit from slightly and mildly thick liquids without risk of worse residue.

Variations in Hyoid Kinematics Across Liquid Consistencies in Healthy Swallowing.

Purpose Judgments regarding hyoid movement are frequently included in evaluations of swallowing. However, the literature lacks reference values for measures of hyoid kinematics in healthy swallowing. This study explores hyoid movement across the continuum from thin to extremely thick liquids. Method Participants were 39 healthy adults under the age of 60 years (19 men) who underwent videofluoroscopy involving three sips each of 20% w/v thin barium and six sips each of slightly, mildly, moderately, and extremely thick barium. Half of the thickened stimuli were prepared using xanthan gum; and half, with a starch-based thickener. Sip volume was derived from pre- and post-sip cup weights. Hyoid position was tracked frame-by-frame relative to the anterior-inferior corner of C4. Measures of peak hyoid position (along the XY axis) were normalized to a C2-C4 scalar, and measures of time-to-peak position, speed, and time-to-peak speed were derived. As a first step, Spearman's correlations confirmed the influence of sip volume on these hyoid measures. Linear mixed-effects models then explored the effects of stimulus, sip volume, and task repetition on the dependent variables. Results The data set comprised 975 swallows with available hyoid tracking data. Sip volume was correlated with peak hyoid XY position (rs = .15, p < .01), time-to-peak position (rs = -.15, p < .05), and speed (rs = .13, p < .01). No significant differences in hyoid kinematics were found across stimuli. Conclusion Measures of hyoid movement in healthy swallowing remain stable across the range from thin to extremely thick liquids with no systematic alterations in hyoid position or kinematics.

Quantitative Videofluoroscopic Analysis of Swallowing Physiology and Function in Individuals With Chronic Obstructive Pulmonary Disease.

Purpose Dysphagia is a serious extra pulmonary manifestation of chronic obstructive pulmonary disease (COPD). However, the nature of abnormalities in swallowing physiology in COPD has yet to be clearly established. We explored the frequency of swallowing measures outside the healthy reference range in adults with COPD. Method Participants were 28 adults aged 41-79 years (18 men, 20 women) with stable COPD. Disease severity was classified as GOLD (Global Initiative For Chronic Obstructive Lung Disease) Stages 1 (4%), 2 (25%), 3 (53%), and 4 (18%). Participants underwent a videofluoroscopy and swallowed 20% w/v thin barium in, followed by 20% w/v mildly, moderately, and extremely thick barium prepared with a xanthan gum thickener. Blinded duplicate ratings of swallowing safety, efficiency, kinematics, and timing were performed according to the ASPEKT method (Analysis of Swallowing Physiology: Events, Kinematics and Timing). Comparison data for healthy adults aged < 60 years were extracted from an existing data set. Chi-square and Fisher's exact tests compared the frequencies of measures falling < 1 SD/ > 1 SD from mean reference values (or < the first or > the third quartile for skewed parameters). Results Participants with COPD did not display greater frequencies of penetration-aspiration, but they were significantly more likely (p < .05) to display incomplete laryngeal vestibule closure (LVC), longer time-to-LVC, and shorter LVC duration. They also displayed significantly higher frequencies of short upper esophageal sphincter opening, reduced pharyngeal constriction, and pharyngeal residue. Conclusion This analysis reveals differences in swallowing physiology in patients with stable COPD characterized by impaired safety related to the mechanism, timing, and duration of LVC and by impaired swallowing efficiency with increased pharyngeal residue related to poor pharyngeal constriction.

Mechanisms of Impaired Swallowing on Thin Liquids Following Radiation Treatment for Oropharyngeal Cancer.

Purpose Dysphagia is one of the most debilitating chronic symptoms experienced by patients who undergo radiation treatment for head and neck cancer. Despite the high prevalence of dysphagia in patients with head and neck cancer, we lack understanding of the specific changes in swallowing physiology that arise in the short-term following radiation therapy and how these changes impact the key functions of swallowing safety and efficiency. This study sought to identify pathophysiological mechanisms underlying impairments in swallowing safety and efficiency on thin liquids following (chemo)radiation for oropharyngeal cancer. Method Videofluoroscopic swallowing studies were completed in 12 male patients within 6 months following completion of (chemo)radiation and in 12 healthy male controls. To compare swallowing function and physiology between groups, we analyzed three discrete sips of 20% w/v thin liquid barium per participant. The videofluoroscopic swallowing study recordings were rated for swallowing safety, efficiency, timing parameters, and pixel-based measures of structural area or movement. Results The oropharyngeal cancer cohort displayed significantly higher frequencies of penetration-aspiration, incomplete laryngeal vestibule closure, prolonged time-to-laryngeal vestibule closure, and poor pharyngeal constriction. Incomplete or delayed laryngeal vestibule closure was associated with airway invasion, while poor pharyngeal constriction was associated with pharyngeal residue. Conclusions This study highlights the primary mechanisms behind impaired safety and efficiency of the swallow in patients following (chemo)radiation for oropharyngeal cancer.

The Risk of Penetration-Aspiration Related to Residue in the Pharynx.

Purpose Reference data from healthy adults under the age of 60 years suggest that the 75th and 95th percentiles for pharyngeal residue on swallows of thin liquids are 1% and 3%(C2-4)2, respectively. We explored how pharyngeal residue below versus above these values prior to a swallow predicts penetration-aspiration. Method The study involved retrospective analysis of a previous research data set from 305 adults at risk for dysphagia. Participants swallowed six thin boluses and three each of mildly, moderately, and extremely thick barium in videofluoroscopy. Raters measured preswallow residue in %(C2-4)2 units and Penetration-Aspiration Scale (PAS) scores for each swallow. Swallows were classified as (a) "clean baseline" (with no preswallow residue), (b) "clearing" swallows of residue with no new material added, or (c) swallows of "additional material" plus preswallow residue. Frequencies of PAS scores of ≥ 3 were compared across swallow type by consistency according to residue severity (i.e., ≤ vs. > 1%(C2-4)2 and ≤ vs. > 3%(C2-4)2. Results The data set comprised 2,541 clean baseline, 209 clearing, and 1,722 swallows of additional material. On clean baseline swallows, frequencies of PAS scores of ≥ 3 were 5% for thin and mildly thick liquids and 1% for moderately/extremely thick liquids. Compared to clean baseline swallows, the odds of penetration-aspiration on thin liquids increased 4.60-fold above the 1% threshold and 4.20-fold above the 3% threshold (mildly thick: 2.11-fold > 1%(C2-4)2, 2.26-fold > 3%(C2-4)2). PAS scores of ≥ 3 did not occur with clearing swallows of moderately/extremely thick liquids. Lower frequencies of above-threshold preswallow residue were seen for swallows of additional material than for clearing swallows. Compared to clean baseline swallows, the odds of PAS scores of ≥ 3 on swallows of additional material increased ≥ 1.86-fold above the 1% threshold and ≥ 2.15-fold above the 3% threshold, depending on consistency. Conclusion The data suggest that a pharyngeal residue threshold of 1%(C2-4)2 is a meaningful cut-point for delineating increased risk of penetration-aspiration on a subsequent swallow.

Measurement of Pharyngeal Residue From Lateral View Videofluoroscopic Images.

Purpose The field lacks consensus about preferred metrics for capturing pharyngeal residue on videofluoroscopy. We explored four different methods, namely, the visuoperceptual Eisenhuber scale and three pixel-based methods: (a) residue area divided by vallecular or pyriform sinus spatial housing ("%-Full"), (b) the Normalized Residue Ratio Scale, and (c) residue area divided by a cervical spine scalar (%(C2-4)2). Method This study involved retrospective analysis of an existing data set of videofluoroscopies performed in 305 adults referred on the basis of suspected dysphagia, who swallowed 15 boluses each (six thin and three each of mildly, moderately, and extremely thick 20% w/v barium). The rest frame at the end of the initial swallow of each bolus was identified. Duplicate measures of pharyngeal residue were made independently by trained raters; interrater reliability was calculated prior to discrepancy resolution. Frequency distributions and descriptive statistics were calculated for all measures. Kendall's τb tests explored associations between Eisenhuber scale scores and pixel-based measures, that is, %-Full and %(C2-4)2. Cross-tabulations compared Eisenhuber scale scores to 25% increments of the %-Full measure. Spearman rank correlations evaluated relationships between the %-Full and %(C2-4)2 measures. Results Complete data were available for 3,545 boluses: 37% displayed pharyngeal residue (thin, 36%; mildly thick, 41%; moderately thick, 35%; extremely thick, 34%). Eisenhuber scale scores showed modest positive associations with pixel-based measures but inaccurately estimated residue severity when compared to %-Full measures with errors in 20.6% of vallecular ratings and 14.2% of pyriform sinus ratings. Strong correlations (p < .001) were seen between the %-Full and %(C2-4)2 measures, but the %-Full measures showed inflation when spatial housing area was small. Conclusions Generally good correspondence was seen across different methods of measuring pharyngeal residue. Pixel-based measurement using an anatomical reference scalar, for example, (C2-4)2 is recommended for valid, reliable, and precise measurement.

A Cross-Sectional, Quantitative Videofluoroscopic Analysis of Swallowing Physiology and Function in Individuals With Amyotrophic Lateral Sclerosis.

Purpose To date, research characterizing swallowing changes in individuals with amyotrophic lateral sclerosis (ALS) has primarily relied on subjective descriptions. Thus, the degree to which swallowing physiology is altered in ALS, and relationships between such alterations and swallow safety and/or efficiency are not well characterized. This study provides a quantitative representation of swallow physiology, safety, and efficiency in a sample of individuals with ALS, to estimate the degree of difference in comparison to published healthy reference data and identify parameters that pose risk to swallow safety and efficiency. Secondary analyses explored the therapeutic effect of thickened liquids on swallowing safety and efficiency. Method Nineteen adults with a diagnosis of probable-definite ALS (El-Escorial Criteria-Revised) underwent a videofluoroscopic swallowing study, involving up to 15 sips of barium liquid (20% w/v), ranging in thickness from thin to extremely thick. Blinded frame-by-frame videofluoroscopy analysis yielded the following measures: Penetration-Aspiration Scale, number of swallows per bolus, amount of pharyngeal residue, degree of laryngeal vestibule closure (LVC), time-to-LVC, duration of LVC (LVCdur), pharyngeal area at maximum constriction, diameter of upper esophageal sphincter opening, and duration of UES opening (UESOdur). Measures of swallow physiology obtained from thin liquid trials were compared against published healthy reference data using unpaired t tests, chi-squared tests, and Cohen's d effect sizes (adjusted p < .008). Preliminary relationships between parameters of swallowing physiology, safety, and efficiency were explored using nonparametric Cochrane's Q, Friedman's test, and generalized estimating equations (p < .05). Results Compared to healthy reference data, this sample of individuals with ALS displayed a higher proportion of swallows with partial or incomplete LVC (24% vs. < 1%), increased time-to-LVC (d = 1.09), reduced UESwidth (d = 0.59), enlarged pharyngeal area at maximum constriction, prolonged LVCdur (d = 0.64), and prolonged UESOdur (d = 1.34). Unsafe swallowing (i.e., PAS ≥ 3) occurred more frequently when LVC was partial/incomplete or time-to-LVC was prolonged. Pharyngeal residue was associated with larger pharyngeal areas at maximum constriction. Unsafe swallowing occurred less frequently with extremely thick liquids, compared to thin liquids. No significant differences in pharyngeal residue were observed based on liquid thickness. Conclusions Quantitative videofluoroscopic measurements revealed moderate-to-large differences in swallow physiology between this sample of individuals with ALS and healthy reference data. Increased time-to-LVC, noncomplete LVC, and enlarged pharyngeal area at maximum constriction were associated with impaired swallow safety or efficiency. Thickened liquids may mitigate the risk of acute episodes of aspiration in individuals with ALS. Further work is needed to corroborate these preliminary findings and explore how swallowing profiles evolve throughout disease progression.