Swallow Event Sequencing: Comparing Healthy Older and Younger Adults

Participant Characteristics for Dysphagia Research: A Proposed Checklist

PURPOSE

Participant characteristics are underreported; however, they impact swallowing impairments and subsequent access to assessment and intervention. Standards for rigorous and transparent reporting of dysphagia research are required. The Framework for RigOr aNd Transparency In REseaRch on Swallowing (FRONTIERS) offers a critical appraisal tool for dysphagia research. This article outlines questions for participant characteristics in dysphagia research as part of the larger FRONTIERS tool.

METHOD

An exploratory literature review was conducted to determine how participant characteristics, eligibility criteria, and definitions of health and dysphagia are reported in the literature. Findings were cross-referenced with other relevant critical appraisal tools. A list of questions was generated and refined iteratively with the entire FRONTIERS collaborative until consensus was met.

RESULTS

The participant characteristics portion of the FRONTIERS tool includes eight questions and 16 possible subquestions. Examples for how the tool might be used, as well as rationales for inclusion of all questions, are included.

CONCLUSIONS

Including detailed characteristics of research participants may support understanding of how best to serve marginalized and underrepresented populations more effectively. Critical appraisal tools, such as FRONTIERS, may help to improve the rigor and transparency in dysphagia research, ultimately improving patient care.

Using Sequence Analyses to Quantitatively Measure Oropharyngeal Swallowing Temporality in Point-of-Care Ultrasound Examinations: A Pilot Study

(1) Background: Swallowing is a complex process that comprises well-timed control of oropharyngeal and laryngeal structures to achieve airway protection and swallowing efficiency. To understand its temporality, previous research adopted adherence measures and revealed obligatory pairs in healthy swallows and the effect of aging and bolus type on the variability of event timing and order. This study aimed to (i) propose a systemic conceptualization of swallowing physiology, (ii) apply sequence analyses, a set of information-theoretic and bioinformatic methods, to quantify and characterize swallowing temporality, and (iii) investigate the effect of aging and dysphagia on the quantified variables using sequence analyses measures. (2) Method: Forty-three participants (17 young adults, 15 older adults, and 11 dysphagic adults) underwent B-mode ultrasound swallowing examinations at the mid-sagittal plane of the submental region. The onset, maximum, and offset states of hyoid bone displacement, geniohyoid muscle contraction, and tongue base retraction were identified and sorted to form sequences which were analyzed using an inventory of sequence analytic techniques; namely, overlap coefficients, Shannon entropy, and longest common subsequence algorithms. (3) Results: The concurrency of movement sequence was found to be significantly impacted by aging and dysphagia. Swallowing sequence variability was also found to be reduced with age and the presence of dysphagia (H(2) = 52.253, p < 0.001, η2 = 0.260). Four obligatory sequences were identified, and high adherence was also indicated in two previously reported pairs. These results provided preliminary support for the validity of sequence analyses for quantifying swallowing sequence temporality. (4) Conclusions: A systemic conceptualization of human deglutition permits a multi-level quantitative analysis of swallowing physiology. Sequence analyses are a set of promising quantitative measurement techniques for point-of-care ultrasound (POCUS) swallowing examinations and outcome measures for swallowing rehabilitation and evaluation of associated physiological conditions, such as sarcopenia. Findings in the current study revealed physiological differences among healthy young, healthy older, and dysphagic adults. They also helped lay the groundwork for future AI-assisted dysphagia assessment and outcome measures using POCUSs. Arguably, the proposed conceptualization and analyses are also modality-independent measures that can potentially be generalized for other instrumental swallowing assessment modalities.

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.

Temporal measures of oropharyngeal swallowing events identified using ultrasound imaging in healthy young adults

Swallowing is a complex process that involves precise coordination among oral and pharyngeal structures, which is essential to smooth transition of bolus and adequate airway protection. Tongue base retraction and hyolaryngeal excursion are two significant swallowing movements, and their related events can be examined using ultrasound imaging, which is physically and radioactively non-invasive. The present study aimed to 1) establish the temporal sequences and timing of swallowing events identified using ultrasound imaging, and 2) investigate the variability of the above temporal sequences and 3) investigate the effect of bolus type on the variability of temporal sequences in non-dysphagic individuals. Forty-one non-dysphagic young adults of both genders (19 males and 22 females) participated in the study. Ultrasound images were acquired mid-saggitally at their submental region during swallowing of boluses with different volume (i.e. 5mL or 10mL) and consistencies (i.e. IDDSI Levels 0 and 4). Timing and sequence of six events 1) displacement onset (TBOn), 2) maximum displacement (TBMax) and 3) displacement offset of tongue base retraction (TBOff); and, 4) displacement onset (HBOn), 5) maximum displacement (HBMax) and 6) displacement offset of the hyoid bone excursion (HBOff) were extracted from the ultrasound images. Out of the 161 swallows, 85.7% follow a general sequence of HBOn < TBOn < HBMax < TBMax < HBOff < TBOff. Percentage adherence to six anticipated paired-event sequences was studied. Results suggested the presence of individual variability as adherence ranged from 75.8% to 98.1% in four of the anticipated sequences, leaving only two sequences (HBOn < TBMax and TBMax < HBOff) obligatory (i.e. 100% adherence). For non-obligatory sequences, it was found that bolus type may have an effect on the level of adherence. Findings of the present study lay the groundwork for future studies on swallowing using ultrasound imaging and also the clinical application of ultrasonography.

Recovery pattern analysis of swallowing function in patients undergoing total glossectomy and hemiglossectomy

OBJECTIVES

To investigate the recovery process of swallowing function and ascertain swallowing pattern in patients undergoing total glossectomy (TG).

MATERIALS AND METHODS

A cohort study was conducted in consecutive patients with tongue squamous cell carcinoma who received TG/hemiglossectomy (HG) from May 2017 to December 2019. Exposure factors included tongue resection range (HG and TG) and postoperative radiotherapy (PRT and non-PRT). The swallowing functions were evaluated by M.D. Anderson dysphagia inventory (MDADI), water swallow test (WST), and tongue pressure (TP) at pretreatment, 1, 4, 7, 12, 18 and 24 months postoperatively. Videofluoroscopy swallowing study (VFSS) was applied to analyze swallowing pattern of TG patients.

RESULTS

A total of 67 patients were enrolled, of which 17 underwent TG and 50 underwent HG. Both MDADI and TP of the TG and PRT group were lower than those of the HG and non-PRT group. TG patients had no evident improvement in MDADI and TP after surgery. There was a higher risk of swallowing unsafety with abnormal WST outcome in TG (P < 0.001, OR = 106.52) than that in HG. VFSS analysis identified prolonged oral and pharyngeal transit time, disorganized swallowing sequence, abnormal hyoid bone movement, and frequent invalid swallows in patients with TG. A shortened OTT (<5066.50 ms) and a larger pharyngeal constriction ratio (PCR > 0.31) were associated with increased risks of penetration and aspiration.

CONCLUSION

Postoperative swallowing pattern is a characteristic of severely impaired safety and efficacy in patients with TG. Impaired OTT and PCR are variables that should be examined when determining the need for rehabilitation treatment.

Latent changes in the pharyngeal stage of swallowing in non-aspirating older adults

PURPOSE

The characteristic changes in the swallowing mechanism with aging are collectively termed presbyphagia. Although several studies have investigated presbyphagia in older adults, few have assessed oldest-old adults. We aimed to characterize the latent changes of swallowing function in oldest-old adults and to consider risk ages for presbyphagia.

METHODS

We analyzed the records of 85 individuals (44 males and 41 females, aged 25-101 years) who underwent videofluoroscopic swallowing studies. The included participants had penetration and aspiration scores of ≤ 2 and no history of aspiration, pneumonia, or diseases that affect swallowing. They were divided into four age groups: 25-64 years (non-older), 65-74 years (young-old), 75-84 years (middle-old), and ≥ 85 years (oldest-old). We analyzed and compared the pharyngeal delay time (PDT), duration of tongue base and posterior pharyngeal wall contact, duration and dimension of upper esophageal sphincter opening (UES-O), and maximal hyoid bone displacement between the age groups.

RESULTS

Among the older groups, the oldest-old showed significantly longer PDT than younger-old adults, and the UES-O tended to be wider in the former. However, no other remarkable differences were found between the oldest-old and other old groups. Statistical comparisons between the < 75 and ≥ 75-year age groups revealed significant age-related changes in the PDT and duration and dimension of UES-O.

CONCLUSION

On videofluoroscopic evaluation, physiological changes with aging affected few parameters of swallowing in our cohort. These findings indicate that in non-aspirating oldest-old adults, any deterioration may be adjusted for by compensatory changes to maintain swallowing function.

A Retrospective Analysis of Swallowing Function and Physiology in Patients Living with Dementia

Dysphagia is commonly diagnosed in patients living with dementia, but we lack understanding of changes in swallowing physiology and the resulting relationship to impairments of safety and efficiency. The purpose of this study was to describe the pathophysiology of dysphagia in a retrospective sample of patients living with dementia. Videofluoroscopy data from 106 adults (mean age: 84) diagnosed with dementia were scored by blinded raters. Raters analyzed 412 thin liquid swallows for safety [Penetration-Aspiration Scale (PAS)], efficiency [% of (C2-C4)²], timing [Pharyngeal Transit Time (PTT), Swallow Reaction Time (SRT), Laryngeal Vestibule Closure Reaction Time (LVCrt), Upper Esophageal Sphincter Opening Duration (UESO)], and kinematics (pharyngeal constriction). Impairment thresholds from existing literature were used to characterize swallowing. Chi-square tests and Pearson's correlations were used to determine associations between swallowing physiology and function. Compared to published norms, we identified significant differences in PTT, SRT, LVCrt, UESO, and degree of maximum pharyngeal constriction. Unsafe swallowing (PAS > 2) was seen in 17% of swallows. Clinically significant residue (i.e., % of (C2-C4)² > 0.54 vallecular; > 0.34 pyriforms) was seen in most patients. Chi-square tests revealed significant associations between LVCrt and unsafe swallowing. There was a weak positive association between post-swallow residue in the pyriforms and poor pharyngeal constriction. Detailed analysis of swallowing physiology in this sample provides insight into the pathophysiological mechanisms associated with dysphagia in patients living with dementia. Further work is needed to explore additional bolus consistencies and to identify how physiology changes based on type and severity of dementia diagnosis.

Diagnosis and treatments for oropharyngeal dysphagia: effects of capsaicin evaluated by newly developed ultrasonographic method

Oropharyngeal dysphagia (OD) is a common symptom in the older people, and may cause fatal complications such as aspiration pneumonia. However, there is no established treatment for OD. The relationship between the transient receptor potential vanilloid 1 (TRPV1) and substance P released by activated TRPV1 was recently demonstrated. Further, there are several reports showing that capsaicin, a specific agonist of TRPV1, can improve OD. Currently, the evaluation of swallowing is mainly performed by videofluoroscopic examination. However, there are no reports on the clinical application of ultrasonography using tissue Doppler imaging. In this review, we describe the pathophysiology and treatments for OD, introduce our novel US method to evaluate cervical esophageal motility, and then outline our clinical study examining the effects of capsaicin, a specific TRPV1 agonist, in older patients with OD.

How Important Is Randomization of Swallows During Kinematic Analyses of Swallow Function?

Purpose In dysphagia research involving kinematic analyses on individual swallow parameters, randomization is used to ensure judges are not influenced by judgments made for other parameters within the same swallow or by judgments made for other swallows from the same participant. Yet, the necessity of randomizing swallows to avoid bias during kinematic analyses is largely assumed and untested. This study investigated whether randomization of the order of swallows presented to judges impacts analyses of temporal kinematic events from videofluoroscopic swallow studies. Method One hundred twenty-seven swallows were analyzed from 18 healthy adults who underwent standardized videofluoroscopic swallow studies. Swallows were first analyzed by two trained raters sequentially, analyzing all kinematic events within each swallow, and then a second time in random order, measuring one kinematic event at a time. Intrarater reliability measurements were calculated between random and sequential swallow judgments for all kinematic events using intraclass correlation coefficient and percent exact agreement within a three-frame tolerance. Results Intraclass correlation coefficients (1.00) and percent exact agreement (89%) were excellent for all kinematic events between analyses methods, indicating there were no significant differences in measurements performed in random or sequential order. Conclusions This study provides preliminary evidence that randomization may be unnecessary during temporal swallow kinematic data analyses for research, which may lead to more efficient analyses and dissemination of findings, and alignment of findings with clinical interpretations. Replication of this design with swallows from people with dysphagia would strengthen the generalizability of the results.

Validity and reliability of a French version of M.D. Anderson Dysphagia Inventory

OBJECTIVE

To assess the internal consistency, reliability, and clinical validity of a French version of the M.D. Anderson Dysphagia Inventory (Fr-MDADI).

METHODS

Patients addressed in the Swallowing Clinics of CHU Saint-Pierre Hospital (Brussels) and EpiCURA hospital (Ath, Belgium) for dysphagia completed Fr-MDADI, eating assessment tool-10 (EAT-10), dysphagia handicap index (DHI), and benefited from fiberoptic endoscopic evaluation of swallowing (FEES) and videofluoroscopy. Seventy-two asymptomatic individuals composed the control group. The reliability of Fr-MDADI was assessed through a test-retest procedure. The validity was assessed by comparing Fr-MDADI with EAT-10 scores. Normative value of Fr-MDADI was calculated through the receiver operating characteristic (ROC) curve.

RESULTS

Forty-two patients and 77 healthy individuals completed the evaluations (33 males). The main etiology of dysphagia was head and neck cancers. The internal consistency was high regarding the Cronbach's alpha (0.864). The test-retest reliability was high for Fr-MDADI total scores (r_s = 0.849). The Fr-MDADI emotional, functional and physical subscores, and the total score exhibited high positive correlations with EAT-10 (r_s = 0.770) and DHI (r_s = 0.811), exhibiting high external validity. Patients had significant higher item and total score of Fr-MDADI compared with healthy individuals (control group), which indicated an adequate internal validity. About normative data, a Fr-MDADI > 13 was considered to be reflective of abnormalities. The 'swallowing-induced cough' item of the Fr-MDADI was significantly associated with the occurrence of aspirations regarding objective examinations (FEES or videofluoroscopy; p = 0.001).

CONCLUSION

The Fr-MDADI is a reliable and valid self-administered tool in the evaluation of the dysphagia of French-speaking patients.

Hyoid-complex elevation and stimulation technique restores swallowing function in patients with lateral medullary syndrome: Two case reports

BACKGROUND

A swallowing disorder may occur following a brainstem stroke, especially one that occurs in the swallowing centers. Lateral medullary syndrome (referred to as LMS), a rare condition in which a vascular event occurs in the territory of the posterior inferior cerebellar artery or the vertebral artery, has been reported to lead to more severe and longer lasting dysphagia.

CASE SUMMARY

We report two patients with dysphagia due to LMS and propose a novel technique named hyoid-complex elevation and stimulation technique (known as HEST). The two patients had no other functional incapacity back into life, but nasogastric feeding was the only possible way for nutrition because of severe aspirations. Swallowing function was evaluated by functional oral intake scale, modified water swallow test, surface electromyographic signal associated with video fluorography swallowing study to assess the situation of aspiration, pharyngeal residue, pharyngeal peristalsis, upper esophageal opening and the ability of deglutition. Both patients were treated with the HEST method for dysphagia and recovered quickly.

CONCLUSION

HEST is effective for shortening the in-hospital time and improving the quality of life for patients with dysphagia who suffer from LMS and likely other strokes.

A Systematic Review of Physiological Changes in Swallowing in the Oldest Old

Age-related swallowing changes are well-researched in deglutology, usually distinguishing those over 60 years as older aged. World-wide, older adults are healthier and forecast to live longer: many over 85 years. It is necessary for clinicians to understand healthy swallowing changes in this 'oldest old' in order to appropriately manage swallowing complaints in older patients. This systematic review collated and critically appraised studies investigating swallowing changes in adults over 85 years using instrumental assessment. Criteria for inclusion were healthy subjects over 85 years. Exclusion criteria included studies focused on anatomy and oral processing. Studies published until December 2018 were retrieved from BIOSIS, CINAHL, Embase, Medline, and Scopus, totaling 2125 articles. During data screening, 64% of studies investigating age-related swallowing changes were excluded, as the oldest old were not recruited. After PRISMA screening, 44 articles met criteria. These were further reviewed for data extraction, bias and quality. Main quantitative age-related changes in swallowing included increases in delay in swallow onset, bolus transit times, duration of UES opening, pressure above the UES and UES relaxation pressure, and reduction in pressure at the UES. Few studies detected increased residue or airway compromise in the form of aspiration. Results were not easily comparable due to differences in age ranges, methods for deeming participants 'healthy', measures used to define swallowing physiology, and swallowing tasks. Age-related swallowing changes are identified that do not compromise safety. The oldest old are underrepresented in normative deglutition research. It is essential future studies plan accordingly to recruit those over 85 years.

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

Purpose Thickened liquids are frequently used as an intervention for dysphagia, but gaps persist in our understanding of variations in swallowing behavior based on incremental thickening of liquids. The goal of this study was to establish reference values for measures of bolus flow and swallowing physiology in healthy adults across the continuum from thin to extremely thick liquids. Method A sex-balanced sample of 38 healthy adults underwent videofluoroscopy and swallowed 20% weight-to-volume concentration barium prepared in thin and slightly, mildly, moderately, and extremely thick consistencies using a xanthan gum thickener. Participants took comfortable sips and swallowed without a cue; sip volume was measured based on presip and postsip cup weights. A standard operating procedure (the ASPEKT method: Analysis of Swallowing Physiology: Events, Kinematics and Timing) was used to analyze videofluoroscopy recordings. Results The results clarify that, for thin liquid sips (10-14 ml), a single swallow without clearing swallows is typical and is characterized by complete laryngeal vestibule closure, complete pharyngeal constriction, and minimal postswallow residue. Aspiration was not seen, and penetration was extremely rare. Bolus position at swallow onset was variable, extending as low as the pyriform sinuses in 37% of cases. With thicker liquids, no changes in event sequencing, laryngeal vestibule closure, pharyngeal constriction, or postswallow residue were seen. The odds of penetration were significantly reduced. A longer timing interval until onset of the hyoid burst movement was seen, with an associated higher bolus position at swallow onset. Other timing measures remained unaffected by changes in bolus consistency. Conclusion The results include new reference data for swallowing in healthy adults across the range from thin to extremely thick liquids.

Validity and reliability of the French version of Eating Assessment Tool (EAT-10)

OBJECTIVE

To develop a French version of the Eating Assessment Tool (Fr EAT-10) and to assess its internal consistency, reliability and clinical validity.

METHODS

Fifty-six patients referred in the Swallowing Clinics of CHU Saint-Pierre Hospital (Brussels) and EpiCURA hospital (Ath, Belgium) for dysphagia were enrolled and completed fiberoptic endoscopic evaluation of swallowing and videofluoroscopy. Seventy-three asymptomatic subjects were included in the study. To assess reliability, Fr-EAT-10 was completed twice within a 7-day period. Validity was assessed by comparing Fr-EAT-10 scores with the scores of dysphagia handicap index (DHI) in all individuals. Normative value of EAT-10 was calculated and the receiver operating characteristic (ROC) curve was used to determine the best Fr-EAT-10 threshold associated with aspiration.

RESULTS

Fifty-two patients completed the study. Cronbach's alpha was 0.95 indicating a high internal consistency. Test-retest reliability was high in the entire cohort (r_s = 0.921). The correlation between Fr-EAT-10 total scores and DHI was high (r_s = 0.827) indicating a high external validity. Patients had a significant higher score of Fr-EAT-10 than the controls (p < 0.001) exhibiting a high internal validity. The analysis of normative data reported that a score of Fr-EAT-10 > 3 should be considered as abnormal. The correlation between Fr-EAT-10 and the occurrence of aspiration is significant (r_s = 0.327, p < 0.05). According to the ROC curve; aspirations need to be highly suspected for patients with Fr-EAT-10 ≥ 17.

CONCLUSION

The Fr-EAT-10 developed in this study is a reliable and valid self-administered tool in the evaluation of dysphagia in French-speaking patients.

Disruption of the Obligatory Swallowing Sequence in Patients with Wallenberg Syndrome

Although the sequence of events involved in swallowing varies among healthy adults, healthy adults demonstrate some consistent patterns, including opening of the upper esophageal sphincter (UES) prior to maximum laryngeal elevation (LE). Previous animal studies suggested that swallowing is regulated by a neuronal network in the medulla, and lateral medullary infarction, or Wallenberg syndrome, frequently causes dysphagia. This retrospective, observational, multicenter study aimed to determine if the sequence of swallowing events was disturbed in patients with Wallenberg syndrome compared with previously published reference data for healthy adults. The study subjects included 35 patients with Wallenberg syndrome admitted to three hospitals in Japan from 1/4/2009 to 31/3/2017. Sixteen timing events, including maximum LE and UES opening, and the intervals between events were measured. If the sequence of events was the same as in healthy adults, the interval value was positive, and if the sequence of events was opposite to that in healthy adults, the value was negative. The median interval from UES opening to maximum LE was - 0.02 s (range - 0.80 to 0.89, 95% CI - 0.14 to 0.10). About half of the Wallenberg cases showed negative values indicating that the sequence was reversed. These results suggest that lateral medullary infarction impairs the sequence of swallowing events.

Dysphagia in Frail Patients Is Not Frailty Dysphagia

Society revolves around food, both as a physical necessity and a social nicety; thus, eating and drinking (and, hence, swallowing safely) have become a cornerstone of social life. [...].