Quantification of static and dynamic supraglottic activity

Area of Science:

• Laryngology
• Speech-Language Pathology
• Voice Science

Background:

• Current methods for assessing supraglottic compression in voice disorders rely on subjective rating scales.
• Objective quantification of supraglottic activity is needed for better differentiation between voice-disordered groups.

Purpose of the Study:

• To develop and validate a method for quantifying static supraglottic activity.
• To quantify the extent of false vocal fold (FVF) motion during dynamic supraglottic activity.
• To investigate differences in supraglottic compression between individuals with and without voice disorders.

Main Methods:

• Transnasal fiberoptic laryngeal examinations were conducted during various speech tasks.
• Single-frame images captured minimum and maximum supraglottic compression.
• Measurements included anterior-to-posterior (A-P) distance, vocal fold length, and area to derive compression metrics.
• Inter-rater reliability was established for both subjective ratings and objective measures.

Main Results:

• Significant differences in normalized static supraglottic compression correlated with rating scale categories.
• Significant differences in normalized dynamic supraglottic compression reflected changes between minimum and maximum compression ratings.
• Voice-disordered groups showed significantly greater static A-P compression compared to controls (p < .03).
• Normalized dynamic FVF compression ratios did not differ significantly between groups.

Conclusions:

• Static supraglottic activity quantification may serve as a diagnostic tool for voice disorders.
• Dynamic supraglottic activity, specifically FVF motion, functions as an articulatory mechanism rather than a sign of disordered laryngeal function.