Evaluation of oral pathology that can cause sudden death - by Autopsy imaging

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K09872
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 57080:Social dentistry-related
• Research Institution: Hokkaido University
• Principal Investigator: minowa kazuyuki 北海道大学, 歯学研究院, 教授 (30209845)
• Co-Investigator(Kenkyū-buntansha): 兵頭 秀樹 北海道大学, 医学研究院, 准教授 (30306154)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 突然死 / autopsy imaging / 口腔体積 / 口腔air space

Outline of Final Research Achievements

This study sought to clarify the relationship between oral air space volume and obstructive sleep apnea syndrome (OSAS) onset, which is influenced by multiple factors, such as jawbone, dentition morphology, and oral soft-tissue volume. (1)50 subjects from deceased cases were divided into two groups: OSAS (25 subjects) and controls (25 subjects). (2) 33 subjects from clinical cases were divided into two groups: OSAS (9 subjects) and controls (24 subjects). In all cases, the CT images of the facial region were obtained, and four parameters of oral area volume were analyzed in deceased and clinical cases, and comparisons and analyses were performed between OSAS and control cases. In deceased cases, oral soft-tissue volume (OSV), oral air-space volume (OAV), and the ratio of OAV to OSV (%air) showed a significant correlation. In clinical cases, OAV and %air showed a significant correlation. Furthermore, the evaluation including the pharyngeal area were similar to this results.

Free Research Field

歯科放射線学

Academic Significance and Societal Importance of the Research Achievements

閉塞性睡眠時無呼吸症候群（OSAS）は、睡眠中に繰り返し起こる呼吸停止を特徴とする睡眠障害で、循環器疾患等の重篤な合併症を引き起こし、突然死の原因となる疾患として知られている。死後・臨床例ともに、口腔体積に対する口腔air space体積の比(%air)、口腔咽頭腔体積に対する口腔咽頭領域のair space volumeの比(%air’)の値が小さければ、OSAS発症のリスクが高く、OSASによる突然死の可能性が高いことが示された。咽頭領域を含めた検証でも、口腔領域のみの計測と同様の結果となった。突然死を惹起しやすい口腔形態がCTで評価でき、突然死の原因の一つを早期に評価可能となった。