Comparing phonation threshold flow and pressure by abducting excised larynges

Area of Science:

• Aerodynamics
• Laryngology
• Speech Science

Background:

• Phonation threshold pressure (PTP) is a key metric for vocal fold function.
• A new aerodynamic parameter, phonation threshold flow (PTF), has been proposed.
• Understanding the sensitivity of these parameters to glottal configuration is crucial for diagnosing vocal fold pathologies.

Purpose of the Study:

• To investigate phonation threshold flow (PTF) as a measurable parameter sensitive to physiological changes.
• To compare the sensitivity of PTF and phonation threshold pressure (PTP) to variations in glottal width.
• To evaluate PTF as a potential indicator for vocal fold diseases.

Main Methods:

• Ten canine larynges were used in an ex vivo bench setup.
• Simulated glottal abduction levels ranged from 0.0 to 4.0 mm using metal shims.
• Subglottal pressure and airflow at phonation onset were recorded as airflow was increased.

Main Results:

• Phonation threshold flow (PTF) showed significant differences across varying posterior glottal widths (1.0-4.0 mm).
• PTF demonstrated a linear increase with increasing posterior glottal width.
• Phonation threshold pressure (PTP) showed no significant change with glottal width variations (P = .941).

Conclusions:

• Phonation threshold flow (PTF) is more sensitive to changes in posterior glottal width than phonation threshold pressure (PTP).
• PTF may serve as a more effective diagnostic indicator for vocal fold diseases linked to abduction.
• This study highlights the potential clinical utility of PTF in laryngology.