Clinical Tests Related to Air Usage During Phonation

Abstract

The maximum phonation time (MPT), mean airflow rate during maximum sustained phonation (MFRm), mean airflow rate during comfortable phonation (MFRc) and phonation quotient (PQ) were measured in 60 normal speakers and 1,556 patients with various laryngeal diseases and the clinical significance of the four tests was investigated. The results were as follows : (1) Differences in test value between the normal and pathological groups were most marked for MPT and least significant for MFRc. (2) In the cases of vocal fold polyp and recurrent nerve paralysis, significant correlations were found between the four test values and the normalized size of glottic gap during phonation. (3) Effects of treatments for vocal fold polyp and vocal fold paralysis were manifested in the value of the four test. (4) In normal subjects, MPT, MFRm and PQ were highly correlated to one another but the correlation between MFRc and the other three parameters was low. In the cases of vocal fold paralysis, all four parameters were highly correlated to each other. The correlation among the four parameters varied in the other disease groups. (5) The results led us to the conclusion that MPT and MFRc should be included in the routine test battery.