Vocal Fold Dissipated Power in Females with Hyperfunctional Voice Disorders

Area of Science:

• Vocal fold biomechanics
• Voice disorder diagnostics
• Ambulatory physiological monitoring

Background:

• Phonotrauma, caused by excessive vocal fold stress, is linked to voice disorders.
• Accurate, noninvasive estimation of vocal fold dissipated power is crucial for understanding phonotrauma during daily activities.
• Current methods for estimating subglottal pressure are not practical for ambulatory monitoring.

Purpose of the Study:

• To determine if laboratory-based vocal fold dissipated power estimates can differentiate individuals with phonotraumatic vocal hyperfunction (PVH).
• To evaluate two alternative methods for estimating subglottal pressure for ambulatory monitoring.
• To provide evidence-based recommendations for ambulatory monitoring of vocal fold dissipated power.

Main Methods:

• Four groups of adult females (PVH, nonphonotraumatic vocal hyperfunction, two control groups) were studied.
• Participants produced /pae/ syllables while wearing a pneumotachograph mask and neck-surface accelerometer.
• Acoustic signals and intraoral pressure (IOP) were recorded; subglottal pressure was estimated from IOP and accelerometer data.

Main Results:

• Individuals with PVH showed significantly higher vocal fold dissipated power when using intraoral pressure estimates (P=0.001, D=1.31).
• No significant difference in dissipated power was found between individuals with nonphonotraumatic vocal hyperfunction and controls.
• An accelerometer-based estimation of subglottal pressure maintained significant discriminative power for PVH (P=0.001, D=1.38).

Conclusions:

• Increased vocal fold dissipated power is a sensitive and specific indicator for PVH within hyperfunctional voice disorders.
• Accelerometer-based estimation of energy dissipation shows potential for clinical use in ambulatory monitoring.
• This method could enable objective assessment of vocal load during daily life activities.