Quantitative visualization of organ fibrosis using the acoustically stimulated electromagnetic method

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K22956
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 90:Biomedical engineering and related fields
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Kenji Ikushima 東京農工大学, 工学(系)研究科(研究院), 教授 (20334302)
• Project Period (FY): 2019-06-28 – 2021-03-31
• Keywords: 臓器線維化 / コラーゲン / 超音波 / 圧電性 / 音響誘起電磁法

Outline of Final Research Achievements

The acoustically stimulated electromagnetic method (ASEM method) is a novel measurement technique for detecting electric polarization (piezoelectric polarization) induced by ultrasonic waves (ultrasound pressure). This polarization is derived from the piezoelectricity of fibrous tissue such as collagen having uniaxial symmetry. Therefore, it is expected that excess collagen accumulation associated with chronic diseases of organs will be detected and imaged. In this study, we performed visualization verification of fibrosis using a rat model of chronic myocardial infarction and renal failure. As a result, (1) since polarization was hardly observed in a healthy heart, a fibrotic distribution was obtained with a clear contrast in the myocardial infarction model. (2) Regarding the kidney, since polarization was also observed in healthy kidneys, a clear significant difference was obtained when evaluated as the polarization occurrence area ratio.

Free Research Field

医工学

Academic Significance and Societal Importance of the Research Achievements

臓器の線維化は、心臓、腎臓、肝臓および肺など、慢性疾患において普遍的に認められる組織変性である。通常、患者から組織の一部を摘出して分析する生体検査（生検）が行われている。生検は患者への負担が大きいため、非侵襲検査が強く求められている。本研究により、超音波を用いた新手法（音響誘起電磁法）を用いて心臓や腎臓等のコラーゲン蓄積を直接画像化できることが実証された。音響誘起電磁法による線維化診断の実現は、患者の負担を軽減し、予後予測が頻繁に検査できる診断技術として新たな価値をもたらすことが期待される。