Measurement of phonation threshold power in normal and disordered voice production

Phonation threshold pressure (PTP) and phonation threshold flow (PTF) are useful aerodynamic parameters, but each is sensitive to different disorders. A single comprehensive aerodynamic parameter sensitive to a variety of disorders might be beneficial in quantitative voice assessment. We performed the first study of phonation threshold power (PTW) in human subjects.

PTP and PTF were measured in 100 normal subjects, 19 subjects with vocal fold immobility, and 94 subjects with a benign mass lesion. PTW was calculated from these two parameters. In 41 subjects with a polyp, measurements were obtained before and after excision. Receiver operating characteristic (ROC) analysis was used to determine the ability of the three parameters to distinguish between controls and disordered groups.

The PTW (p < 0.001), PTP (p < 0.001), and PTF (p < 0.001) were different among the three groups. All parameters decreased after polyp excision. PTW had the highest area under the ROC curve for all analyses.

PTW is sensitive to the presence of mass lesions and vocal fold mobility disorders. Additionally, changes in PTW can be observed after excision of mass lesions. PTW could be a useful parameter to describe the aerodynamic inputs to voice production.