Flexible and Expandable RF Coil System with Soft Actuators for Deep Organ Imaging in MRI

This study presents a flexible and expandable RF coil system for magnetic resonance imaging (MRI) of deep organs, such as pituitary glands. To adjust the size of the coil, a 3D folding structure made of PDMS and soft actuators are utilized. Also, the deployable RF coil system featuring both flexibility and high conductivity is implemented using an RF coil composed of conductive polymers. A combination of stereolithography, 3D printing, and PDMS casting techniques was used to efficiently fabricate complex structures, and a system is implemented that allows coil control by soft actuators. Additionally, a remote tuning circuit was used to adjust the operating frequency of the RF coil. It is confirmed that although the operating frequency changes as the shape of the RF coil changes according to the folding structure, the operating frequency can be maintained constant by remote circuit adjustment. This technology allows for the insertion of RF coils for MRI by reducing their diameter during the process of placing them as close as possible to deep-seated organs. This presents the potential to effectively acquire MRI images of various body parts while maintaining patient comfort and improving image quality.