Development of Advanced Medical Systems

Visualization of Cancer

Cancer (malignant tumors), one of the three major diseases, can be effectively controlled through early detection and treatment, thereby reducing cancer-related mortality. Consequently, there is significant interest in the development of magnetic particle imaging, a technique that uses magnetic nanoparticles to easily visualize the location of tumors. With the goal of applying magnetic particle imaging to the human body, our laboratory is conducting research aimed at advancing both the hardware—specifically magnetic sensors and their associated circuitry—and the software—including numerical analysis techniques such as inverse problem solutions.


MPI scanner developed by our laboratory (hardware development)


Cancer location estimation results obtained using the MPI scanner developed by our laboratory (software development) [1]


To perform magnetic imaging of magnetic nanoparticles, it is necessary to understand their magnetic properties. Therefore, in addition to developing devices to measure these magnetic properties, we are also conducting basic research, such as analyzing the behavior of these properties through numerical simulations.



Estimation of the magnetic moment distribution of Resovist using the SVD method and fitting results based on a mixed log-normal distribution [2]


M-H curve obtained using the magnetic measurement system developed in our laboratory (Resovist, 20 kHz) [3]


参考文献

[1] T. Sasayama, S. Taue, T. Yoshida, "Magnetic particle imaging using a multi-axis optically pumped magnetometer and multiple flux transformers," Sensing and Bio-sensing Research, vol. 51, Art. no. 100936, 2026. DOI:10.1016/j.sbsr.2025.100936 (Open access)

[2] T. Sasayama, T. Yoshida, M. M. Saari, and K. Enpuku, "Comparison of volume distribution of magnetic nanoparticles obtained from M-H curve with a mixture of log-normal distributions," J. Appl. Phys., vol. 117, Art. no. 17D155, 2015.DOI: 10.1063/1.4919268

[3] T. Sasayama, T. Yoshida, K. Tanabe, N. Tsujimura, and K. Enpuku, "Hysteresis Loss of Fractionated Magnetic Nanoparticles for Hyperthermia Application," IEEE Trans. Magn., vol. 51, no. 11, Art. no. 5101504, 2015. DOI: 10.1109/TMAG.2015.2438080


Last Update: April 24, 2026