Dynamic Linear Gradient Array for Traveling Wave Magnetic Particle Imaging

Magnetic particle imaging (MPI) is a young imaging modality using the nonlinear magnetization properties of superparamagnetic iron-oxide nanoparticles to acquire them. It is a highly sensitive and fast method allowing both a quantitative and a qualitative analysis of the measured signal. Since its first publication in 2005, several different scanner types have been presented. Most of them work with permanent magnets and therefore have a small field of view. In 2014, an alternative scanner concept, the traveling wave MPI (TWMPI), was presented, which allows scanning an entire mouse-sized volume at once. In this paper, a detailed description of the main field generator, the dynamic linear gradient array (dLGA), used for TWMPI is given. This paper guides the reader to the first dLGA prototype, deriving relations between the length of the dLGA and the diameter of the segment coils.