3-Poles Magnetic Coupler for Inductive Link of Transcutaneous Implantable Device in MR Imaging

Abstract

The number of patients who are implanted electronic medical devices has been rapidly increasing in recent years. However, for the patients of implanted electronic medical devices, scanning in the MRI bore has dangerous matter since the implantable electronic medical devices containing internal magnet would produce inevitable risk factors, such as, strong pulling force and torque generation, by strong base magnetic field. In this paper, an improved fixation magnet method which is applicable implantable medical device for MRI scanning of patient is proposed. This method can reduce risk factors during MRI scanning process by canceling the generated magnetic force of each permanent magnet in transcutaneous signal and power transmission coil of the implantable device. To effectively cancel out the generated magnetic force between implanted magnet and base magnetic field of MRI, the 3-poles magnet method is introduced. Using the proposed 3-poles magnet, in-vitro tests were performed in the 1.5 T MRI. As the result, risk factors were markedly diminished. So, if patients using implantable electronic medical devices including 3-poles magnet undergo a MRI scan, the possibility of magnet protrusion from implanted device can be avoided.