Mitsubishi Electric, Okayama University, and Osaka University develop magnetic particle imaging device capable of producing images of human brain

Mitsubishi Electric, Okayama University and Osaka University’s Graduate School of Engineering have developed a magnetic particle imaging device capable of sensitive imaging of magnetic particles in an area equivalent in size to that of the human brain, in a project supported by the Japan Agency for Medical Research and Development (AMED). The device operates at low frequencies of 1 kHz or less, a world-first, allowing the use of a significantly smaller power supply unit. The utilization of this device to image magnetic particles that bind to amyloid-β, the causative agent of Alzheimer’s, will allow the accumulation and distribution of amyloid-β to be quantified. The aim is to allow imaging-based assessments of the likelihood of Alzheimer’s developing prior to the onset of the disease.

In August, a panel of experts from Japan’s Ministry of Health, Labour and Welfare gave a green light for the manufacture and sale of a drug that targets the accumulation of amyloid-β in the brain, a potential factor in the development of Alzheimer’s, thereby inhibiting the progression of the disease. Initiating medication early during a phase of low amyloid-β accumulation in the brain has been shown to help suppress the onset of the disease. This underscores the necessity for technology capable of measuring both the accumulation and distribution of amyloid-β.The magnetic particle imaging device deploys an alternating magnetic field generated by a coil to induce magnetic signals from magnetic particles injected into the body; it then uses these signals to produce a three dimensional image. A higher frequency alternating magnetic field enhances the sensitivity of signal detection.

In compact devices designed for testing on small animals such as mice, which have already been commercialized, frequencies of approximately 25 kHz are used. One of the factors that hitherto hindered the practical application of this system in the treatment of humans was the extremely large size of the power supply unit needed to drive the much larger coil. The three participating organizations successfully developed a magnetic particle imaging device capable of sensitively capturing images of magnetic particles across an area equivalent to the size of the human brain; while operating at low frequencies below 1 kHz, a world-first, significantly reducing the size of the power supply unit required. This accomplishment marks a significant stride toward the realization of imaging tests that can assess the likelihood of the development of Alzheimer’s prior to its onset.