Establishment of a method evaluating inappropriateness of loud voice phonation in the development of vocal nodules

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K11382
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Otorhinolaryngology
• Research Institution: Osaka University
• Principal Investigator: Ogawa Makoto 大阪大学, 医学系研究科, 招へい教授 (80403179)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 大声発声 / 音圧レベル / 喉頭抵抗 / 呼気努力 / 加速度計 / 電気声門図 / マノメトリー

Outline of Final Research Achievements

The aims of the present study were to establish methodology for estimating the appropriateness of loud voice phonation. By using a neck-surface accelerometer we succeeded in simultaneously and continuously evaluating the amount of acoustic output during a gradual increase while phoning a vowel (vowel crescendo task). In addition, the degrees of vocal fold contact and expiratory effort were estimated using electroglottography and esophagogastric manometry. The results revealed the existence of individual differences in the dependence of the increase of vocal intensity on the laryngeal resistance and expiratory effort. such as an abrupt increase in sound pressure level due to excessive vocal fold contact or an insufficient increase in the intra-gastric pressure.

Free Research Field

喉頭科学、音声言語医学

Academic Significance and Societal Importance of the Research Achievements

声帯ポリープ・声帯結節・喉詰め発声などの音声障害の最大リスク因子は習慣的な大声発声であるが、大声発声を呼気努力依存ではなく、喉頭抵抗依存性に行う者が音声障害を発症しやすいと仮定される。本研究では、健常人に母音を発声しながら声を大きくしていくクレシェンド課題を行わせ、その間の音響出力・声帯内転・呼気努力の程度を同時かつ連続的に記録する方法を確立し、健常人の約半数が大声発声時に過剰な声帯内転により音圧レベルの急激な増大を生じることが明らかとなった。将来このような症例に正しい大声発声法を指導することで将来の音声障害発症の予防、、声の衛生に関する知識の啓蒙、および医療費の減少に繋がる可能性がある。