Exploration of swallowing function and food properties affecting pharyngeal residues -Evaluation of pharyngeal residues by retronasal aroma-

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K24115
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0907:Oral science and related fields
• Research Institution: Niigata University
• Principal Investigator: Okawa Jumpei 新潟大学, 医歯学系, 助教 (10846041)
• Project Period (FY): 2019-08-30 – 2022-03-31
• Keywords: 咽頭残留 / 嚥下機能 / レトロネーザル / ニオイセンサ

Outline of Final Research Achievements

Residual food in the pharynx (pharyngeal residue) causes aspiration pneumonia, however no method has been established to assess its residual amount. The aroma released from food during eating is transported to the nasal cavity via the pharynx. We hypothesized that the amount of the pharyngeal residue can be evaluated by measuring the aroma intensity from the nostrils.
Essence was dispensed into the pharynx of healthy adults and the aroma intensity using an odor sensor from the nostril. As a result, the aroma intensity increased as the amount of the essence in the pharynx increased. In addition, by calculating the approximate curve to estimate the aroma intensity, the amount of the pharyngeal residue could be predicted in a short time. Furthermore, the thickened water used for dysphagia patients releases the aroma stably. It is suggested that the amount of the pharyngeal residual can be evaluated in the dysphagia patient.

Free Research Field

歯科補綴学

Academic Significance and Societal Importance of the Research Achievements

超高齢社会を迎えた日本では、肺炎は死因の第３位を占め、その多くは誤嚥性肺炎である。しかし、誤嚥の原因となる食品の咽頭への残留を簡便かつ定量的に評価する方法は確立されておらず、多くは嚥下造影や嚥下内視鏡による定性的な評価にとどまっている。そこで、食品から放出された香りが咽頭から鼻腔へと流れる経路（レトロネーザル）に着目し、香りの強さを測定することで咽頭残留の量を測定する研究を行っている。本研究から、咽頭残留の簡便かつ定量的な評価が可能となれば、食品物性や嚥下機能と関連付けた咽頭残留の評価が可能となり、嚥下障害の病態解明やリハビリテーションに貢献できるものと考えている。