Quantitative Mapping of Electromagnetic Properties of Biological Tissues Using MRI

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K20424
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0302:Electrical and electronic engineering and related fields
• Research Institution: The University of Tokyo
• Principal Investigator: FUSHIMI Motofumi 東京大学, 大学院工学系研究科(工学部), 特任助教 (50907938)
• Project Period (FY): 2021-08-30 – 2023-03-31
• Keywords: MRI / 導電率 / 誘電率 / 逆問題 / 定量画像化 / 磁化率

Outline of Final Research Achievements

This study aims at mapping the distribution of electrical properties (conductivity and permittivity) and magnetic properties (susceptibility) of biological tissues based on MRI measurements, which are useful for diagnosing lesion sites and evaluating biological heating. Throughout the research period, we worked on sequence optimization and winding design of the receiving coils using inverse problem analysis techniques. We created a prototype coil based on the designed winding shape and connected it to an MRI device to perform phantom imaging. By developing measurement techniques that complement the mathematical methods that have been developed, we were able to improve the practicality of the entire modality.

Free Research Field

医用画像

Academic Significance and Societal Importance of the Research Achievements

生体組織の導電率・誘電率や磁化率は病変の有無や進行度を反映するバイオマーカーの役割を果たし、その分布情報を画像化することでがんや神経変性疾患といった病変の特定や早期診断に役立つ。これまでにMRI磁場データから電磁気特性を再構成する数理手法開発に取り組んできた。しかしながら、臨床応用に向けた実用性向上のためには、MRI計測部分での撮像時間短縮やSN比の向上が必要不可欠である。本研究では、MRIの撮像シーケンス開発および受信コイルの最適化を行うことで上記の目的を達成し、これまでの画像再構成から新たに計測までが一体となった、包括的な「電磁気特性画像化モダリティの開発」を進めることができた。