Hyolaryngeal Movement During Normal and Effortful Swallows Determined During Ultrasonography

Area of Science:

• Swallowing biomechanics
• Deglutition physiology
• Geriatric oropharyngeal function

Background:

• The effortful swallow is a technique used to increase hyolaryngeal excursion.
• Understanding variations in effortful swallow techniques is crucial for optimizing swallowing function.
• Investigating age-related differences in swallowing physiology is important for managing dysphagia.

Purpose of the Study:

• To compare the effects of two effortful swallow instructions (tongue emphasis vs. pharyngeal squeezing) on hyoid displacement and hyoid-larynx approximation.
• To examine the relationship between tongue pressure and hyolaryngeal movement during normal and effortful swallowing.
• To assess age-related differences in hyolaryngeal movement during different swallowing tasks.

Main Methods:

• Forty healthy adults (20 younger, 20 older) performed normal and effortful swallows (tongue emphasis, pharyngeal squeezing).
• Hyolaryngeal movement was measured using ultrasonography.
• Tongue pressure was recorded with the Iowa Oral Performance Instrument; submental surface electromyography tracked swallows.

Main Results:

• Both effortful swallow types increased hyolaryngeal movement compared to normal swallows.
• Effortful swallow with tongue emphasis produced greater hyolaryngeal movement than pharyngeal squeezing.
• Tongue pressure positively correlated with hyolaryngeal movement in normal and tongue-emphasis effortful swallows.
• Age differences were observed only in hyoid-larynx approximation during the tongue-emphasis effortful swallow (younger > older).

Conclusions:

• Effortful swallow instructions differentially affect hyolaryngeal movement, suggesting tailored clinical application.
• Normal aging does not appear to impair the ability to perform the effortful swallow or its impact on hyolaryngeal movement.
• The tongue's role in generating pressure is critical for hyolaryngeal movement during swallowing.