Chunlei Liu

Digital and Programmable Magnetic Resonance Imaging (MRI) RF System

MRI is an essential tool for medical diagnosis, and it is ubiquitous in modern medicine. MRI machines use radiofrequency (RF) coils to excite and receive imaging signals. Since the inception of MRI, these RF coils are made of analog resonant circuits in which circuit components are carefully chosen to produce signals at a precisely defined and fixed frequency that is unique to each chemical element of interest. The resonant coil, while providing high signal-to-noise ratio, is laborious, difficult and expensive to manufacture. As a dramatic departure from the conventional approach, the team has invented a new type of RF coil powered by DC currents that can be digitally programmed on the fly to image any chemical element at any frequency. It does not rely on resonant circuits nor high-power RF amplifiers. It can be manufactured with standard printed circuit board assembly. With this technology, the team aims to transform the RF system of MRI from the analog to the digital age. This will not only improve existing MRI capabilities with better efficiency but also accelerate broad adoption of new emerging imaging techniques.