開放性鼻声の客観的判定 経鼻腔音圧，経口腔音圧と聴覚判定について

Abstract

Objective measurement of nasality is important for clinical estimation of speech competence in patients with repaired cleft palate. Since nasality is caused by intermixing of phonic energies in the nasal and oral channels, it is considered to as a best direct method for estimating the nasality objectively to separate the sound energy from the mouth and that from the nose by a shield plate and measure them individually. The grade of nasality (hyper nasality, slight hyper-nasality and no nasality) could be measured reliably by comparing voice judgments with oral and nasal sound pressure levels by this shield plate method.The vowels /a/, /e/and /o/, which all require a low tongue position, showed a good correlation between the rank-ordered listner's judgment on the nasality and the value of “oral sound pressure n-onus nasal sound pressure”. The vowels /i/and /u/, which require a high tongue position, could not be classified distinctly but was useful to determine the presence of nasality.Because of its simplicity, this method is believed to be a potentially valuable clinical tool.