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.

Effortful Swallow Maneuver and Modifications on Swallow Dynamics in Healthy Adults

INTRODUCTION

Effortful swallow (ES) is a widely used technique in dysphagia management, believed to strengthen oropharyngeal muscles and enhance swallowing safety and efficiency. Although its impact on the oral phase of swallowing is well documented, its effects on pharyngeal swallowing physiology remain inconsistent. This study aimed to elucidate the effects of ES on swallowing kinematics and timing, addressing existing inconsistencies in the literature.

METHODS

This study involved 22 healthy adults using archived videofluoroscopic swallowing studies. Participants performed three swallow trials of 10 mL puree under regular conditions and with the ES maneuver. The outcome measures comprised swallow timing and kinematic measures. Swallow timing parameters included time to maximum hyoid and laryngeal excursion, laryngeal vestibule closure (LVC) reaction and duration, pharyngeal constriction duration, pharyngoesophageal segment (PES) opening duration, and swallow duration. Swallow kinematic parameters encompassed hyoid and laryngeal excursions, pharyngeal constriction ratio, and maximum PES width. All variables were analyzed via videofluoroscopy. Paired t tests were used to examine the effect of ES on each outcome measure, with a significance threshold set at p < 0.004.

RESULTS

The ES maneuver significantly increased the duration of LVC, pharyngeal constriction, PES opening, and overall swallow duration. It also improved the pharyngeal constriction ratio. However, there were no significant changes in hyoid and laryngeal excursions. Submental muscle activity showed a notable increase during ES.

CONCLUSION

The study demonstrates that ES can effectively modify certain temporal and kinematic aspects of swallowing, particularly by prolonging key phases and enhancing pharyngeal constriction. These findings suggest the potential utility of ES in dysphagia rehabilitation, especially in cases that require prolonged pharyngeal constriction, LVC, and PES opening. However, the limited impact on hyoid and laryngeal excursions along with LVC reaction time indicates that ES may not address all aspects of dysphagia. The findings highlight the need for tailored therapeutic approaches in dysphagia management, considering individual physiological impairment profiles.

Effects of Varying Transcutaneous Electrical Stimulation Pulse Duration on Swallowing Kinematics in Healthy Adults

Prior research in swallowing physiology has suggested that using submental transcutaneous electrical stimulation (TES) with short pulse duration (PD) (300 μs) may enhance the impact on deep extrinsic tongue muscles, thereby pulling the tongue down during swallowing. However, it was unclear whether that same TES protocol could have a differential impact on hyolaryngeal kinematics and timing. This study aimed to compare the effect of submental TES with varying PDs on anterior and superior hyolaryngeal kinematics and timing both at rest and during swallowing in healthy adults. Twenty-four healthy adults between the ages of 22 and 77 participated in this study. Anterior and superior hyolaryngeal excursion magnitude and duration measures were collected using videofluoroscopic swallowing study. Each subject swallowed three 10 ml pudding trials under three conditions: no TES, TES with short PD (300 μs), and TES with long PD (700 μs). TES was delivered using two-channel surface electrodes in the submental area. In both short and long PD conditions, TES amplitude was gradually increased until participants reached their maximum tolerance level. Videofluoroscopic data were analyzed using VideoPad Video Editor and Image J programs. One-way repeated measure ANOVAs were conducted to identify within-subject effect of TES condition. For hyoid movement, TES with short PD selectively placed the hyoid bone on a more anterior position at rest and reduced anterior hyoid excursion during swallowing compared with the no TES condition. Regarding laryngeal movement, both TES protocols resulted in the larynx taking on a more anterior position at rest and reduced anterior laryngeal excursions during swallowing when compared with the no TES condition. Varying PDs had no significant effect on the superior hyoid and laryngeal movements at rest and during swallowing. Both TES protocols induced shorter hyoid elevation duration during swallowing Findings suggest that though both TES protocols demonstrated a comparable impact on reducing anterior laryngeal excursions, the TES protocol with short PD had an enhanced effect on reducing anterior hyoid excursion during swallowing. This reduced range of motion may result from stimulating the deep submental muscles, which primarily place the hyoid and larynx into a more forward position before swallowing onset. Overall, the TES protocol with short PD may have an increased benefit in facilitating swallowing in patients with dysphagia.

Effects of Effortful Swallowing Exercise with Progressive Anterior Tongue Press Using Iowa Oral Performance Instrument (IOPI) on the Strength of Swallowing-Related Muscles in the Elderly: A Preliminary Study

The purpose of this study was to confirm the effect of effortful swallowing (ES) exercise programs applied to increase the swallowing-related muscle strength in the elderly. In this study, 20 healthy elderly people (76.65 ± 5.87 years; 10 women and 10 men) participated and exercised for 7 weeks. The experimental group performed ES exercise combined with external resistance using Iowa Oral Performance Instrument (IOPI), and the control group performed pure ES without external resistance. The exercises were performed for 20 min a day, 2 days a week for 7 weeks in both groups. ES was repeated 60 times in weeks 1 and 2, 80 times in week 3 and 4, and 120 times in weeks 5-7. In the experimental group, the isometric and swallowing tongue pressures at week 8 were significantly improved compared to baseline. At week 8, the anterior and swallowing tongue pressures and anterior tongue endurance were significantly higher than those of the control group. In the control group, no significant change in tongue pressure-related variables was observed after 7 weeks of exercise. ES exercise combined with IOPI resistance for 7 weeks tended to increase the suprahyoid muscle activation level without statistical significance. For clinical application of this exercise protocol, further studies including more elderly people and patients with dysphagia are required.

Aspects of the assessment and management of pharyngoesophageal dysphagia

Swallowing complaints are common and may have significant consequences for nutrition and pulmonary health. Etiology varies and different aspects of the deglutitive system may be affected. A thorough assessment from the oral cavity to the stomach will provide physiologic information that enables specific targeted management plans to be devised. Although the swallow trajectory bridges anatomic areas, there has previously been a tendency to compartmentalize assessment and treatment by arbitrary anatomic boundaries. It is now clear that this approach fails to appreciate the complexity of swallow mechanics and that systems (oral, pharyngeal, esophageal, and pulmonary) are intertwined and codependent. Swallowing specialists from different backgrounds and with complementary skill sets form a multidisciplinary team that can provide insight and address multiple areas of management. With the advent of new tools for instrumental evaluation, such as manometry, targeted rehabilitative strategies can be informed by physiology, increased in precision and breadth, and assessed quantitatively. Surgical approaches have evolved toward endoscopic techniques, and food technology is expanding options in dietary management. The multidisciplinary team is core to managing this varied and often neglected patient population. This review is for clinicians treating swallowing disorders and will explore the selected aspects of the assessment and management of pharyngoesophageal swallowing disorders.

Effectiveness of Different Application Parameters of Neuromuscular Electrical Stimulation for the Treatment of Dysphagia after a Stroke: A Systematic Review

Background: Dysphagia causes severe complications among people with a stroke. Physiotherapy allows the cure of this pathology, and among the tools it offers is neuromuscular electrical stimulation. However, this is a technique that has not been protocolized. Therefore, it was considered necessary to carry out a systematic review on the efficacy of the various parameters of application of the neuromuscular electrical stimulation in dysphagia generated after a stroke. Methods: A systematic search for publications was conducted in March 2020 in the Pubmed, Cinahl, Medline, Web of Science and Scopus databases, using as search terms: Electric stimulation therapy, Deglutition disorders and Stroke. Results: 21 articles were obtained in which the application of neuromuscular electrical stimulation was applied in isolation (n = 7) or in combination with other techniques such as strengthening exercises and manual therapy techniques (n = 14), with this second modality of treatment having greater benefits for patients. Conclusion: The greatest efficacy of this technique is reached when applied at 60-80 Hz, 700 μs of pulse duration, at the motor intensity threshold and in sessions of 20–30 min.

Systematic Effortful Swallowing Exercise Without External Resistance Does Not Increase Swallowing-Related Muscle Strength in the Elderly

Effortful swallow (ES) is a maneuver intended to increase pressure on a bolus by swallowing and pushing with sufficient force to facilitate clearance. Although ES is mainly known for its immediate effects, the long-term effects of applying ES as an exercise program remain unclear. This study investigated the effects of a 7-week systematic ES exercise regime on swallowing-related muscle strength in individuals aged 65 years and over. In total, 30 healthy older adults participated in this study (16 women and 14 men, aged 67-90 years). The subjects participated in the exercise program for 20 min a day, twice a week, for 7 weeks. To gradually increase exercise intensity, the number of exercises per session was increased from the initial 60 repetitions (weeks 1-2) to 120 repetitions (weeks 5-7). To measure the effect of the strengthening exercise program, the activation level of suprahyoid muscles was measured using surface electromyography, and a tongue pressure measurement system was used to measure variables related to tongue strength (isometric tongue pressure, swallowing tongue pressure, and tongue endurance). Although the effect of ES exercise on muscle strength through gradual adjustment of exercise frequency was not confirmed, ES remains valuable as an exercise for strengthening the muscles involved in swallowing. Future studies are warranted to determine the effects of ES exercise after adjusting for other variables of exercise intensity.

A comparison of neuromuscular electrical stimulation and traditional therapy, versus traditional therapy in patients with longstanding dysphagia

PURPOSE OF REVIEW

Dysphagia in adults arises from a range of causes including acquired neurological disorders and some cancers. Previous research has suggested that treatment using neuromuscular electrical stimulation (NMES) when used in conjunction with conventional therapy is effective. This review describes the recent literature and a small prospective case series carried out in the United Kingdom. This study contributed to support National Institute of Clinical Excellence (NICE) guidance for clinicians who wish to include NMES in a rehabilitation programme for dysphagic patients, specifically with reference to safety and the impact on swallowing function of this intervention.

RECENT FINDINGS

In 2014, the UK NICE issued guidelines enabling UK therapists to trial the use of NMES, but the guidelines also sought additional evidence on the impact on swallowing function of NMES and the incidence of side effects. This small prospective case series investigated both of these aspects with a group of patients with dysphagia of neurological origin who had not achieved adequate swallowing function with traditional therapy alone. This study recruited 10 adult patients with dysphagia of neurological origin. All had previously received traditional swallowing therapy for at least 6 months but only achieved a Functional Oral Intake Scale of 4 or less (a scale for amounts and types of oral intake). The total study period was 10 weeks for each subject comprising 5 weeks of traditional therapy delivered three times a week followed by 5 weeks of NMES concurrent with traditional therapy (NMES + traditional therapy) delivered three times a week using the VitalStim stimulator (VitalStim Therapy, UK). In addition, the Quality of Life in Swallowing and Eating Assessment Tool 10 (quality of life scales) were determined to allow comparison between studies. Nine subjects achieved an improvement in swallowing function after NMES + traditional therapy was measured using the Functional Oral Intake Scale, giving a statistically significant improvement (P < 0.001) when NMES + traditional therapy was compared with traditional therapy. In addition, there was a low incidence of adverse effects with only minor adverse events occurring in 1.3% of electrode pair placements.

SUMMARY

The current preliminary study suggests that NMES + traditional therapy has a good safety record and may improve oral intake and patient reported swallowing outcomes for subjects with long-standing dysphagia of neurological cause, which has not responded to traditional therapy. Provided care is taken with skin preparation and electrode placement the risk of adverse effects from the treatment was minimal. Significantly, in 30% of the subjects, an improvement in voice quality was found.

Alterations to Swallowing Physiology as the Result of Effortful Swallowing in Healthy Seniors

A significant proportion of healthy seniors report difficulty swallowing, thought to result from age-related decline in muscle bulk/function. Effortful Swallowing (ES) is used both as a compensatory maneuver to improve pharyngeal propulsion/clearance and has been proposed as an exercise to improve pharyngeal strength. This study sought to quantify the immediate kinematic, temporal, and functional changes during an ES maneuver to quantify its exercise potential to combat age-related changes in swallowing. Videofluoroscopy data were collected from 44 healthy seniors (21 male) over 65 years old (mean = 76.9, SD = 7.1). Each participant swallowed six 5 ml boluses of Varibar nectar-thick liquids: three with regular effort and three using ES. Individual swallows (n = 260) were measured on pharyngeal constriction, pharyngeal shortening, laryngeal closure duration, hyoid movement duration, UES opening duration, stage transition duration, pharyngeal transit time, pharyngeal response duration, Normalized Residue Ratio Scale (NRRS), and the Penetration-Aspiration Scale (PAS). Non-parametric Wilcoxon Rank Sum for repeated measures tested the effect of ES on each outcome. Exact p-values were calculated based on permutation methods, individual p values < 0.008 was deemed to be significant. The ES maneuver significantly prolonged all temporal variables. While we found no significant differences for pharyngeal constriction, significantly less (i.e., worse) pharyngeal shortening was observed in ES condition compared with regular effort swallows. Further, significantly worse pyriform sinus residue (NRRSv) was observed in the ES condition. No differences between ES and regular effort swallows were noted for pharyngeal constriction, NRRSv or PAS. We speculate that these negative manifestations of worse kinematics (less pharyngeal shortening) and function (increase in NRRSp) may be the result of forced volitional manipulation of swallowing in the ES condition in an otherwise normal elderly swallow.