Phonatory Function Test in Normal and Pathologic Larynges

Abstract

Aerodynamic test for phonatory function have focused on the interrelations of vocal pitch and intensity levels and air flow rate through the glottis supported by subglottic pressures in laryngeal diseases.
We examined the aerodynamic phonatory test for normal and laryngeal dysfunction, and discussed the clinical evaluation of the parameters such as Maximum phonation time (MPT), mean flow rate (MFR), Vocal velocity index (VVI), subglottal pressure (Psub) and Laryngeal efficiency (acoustic power/subglottic power : Le) sustained vowel /a/ phonation at maximum intensity and several seconds at comfortable pitch and intensity levels.
PS-77 equipment and the P1-201 computer analyzing system developed by Iwata in our clinic were utilized. To obtain the correct parameters, several clinical observation of the phonatory function test were explained precisely.
Although the values of these parameters may not give us the diagnosis, the data showed the degree of dysfunction and provided on objective evolution of larygeal diseases especially to compare with the data between pre and post treatments.