Hyolaryngeal Movement During Normal and Effortful Swallows Determined During Ultrasonography

Hyolaryngeal Kinematics in Primary Muscle Tension Dysphonia Determined by Ultrasound

OBJECTIVES

The purpose of this study was to determine hyolaryngeal kinematics during voicing in people with primary muscle tension dysphonia (pMTD) compared with healthy speakers, and to investigate the relationships between hyolaryngeal displacement and self-perceived vocal function.

METHODS

Twenty-six participants, 13 with pMTD and 13 healthy speakers, were assessed using sonography during sustained vowel phonation and rest. Displacement of the hyoid bone and thyroid cartilage was measured from still frames extracted from ultrasound video recordings, with measures normalized to reflect change from rest during voicing for each participant. Vocal function was determined for all participants through self-perceived speaking effort and the Voice Handicap Index-10.

RESULTS

Normalized displacement of the hyoid bone and thyroid cartilage was significantly greater during voicing for participants with pMTD than for the healthy speakers. Weak-to-moderate, nonsignificant relationships between hyoid displacement and vocal function measures were evidenced, whereas moderate-to-strong, significant relationships were found for thyroid displacement and vocal function measures.

CONCLUSIONS

Displacement of the hyoid and elevation of the larynx during phonation appear to be prominent features of pMTD that differentiate the disorder from healthy phonatory kinematics. Ultrasound imaging provides a sensitive, reliable, noninvasive, and feasible method for objectively determining hyolaryngeal kinematics and may be useful for differential diagnosis and determination of treatment outcomes in pMTD.

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.

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.