Magnetic particle imaging method based on non-ideal field free point

A magnetic particle imaging method based on a non-ideal Field Free Point (FFP), comprising the following steps:

• S1, setting external magnetic field conditions of a non-ideal FFP and an ideal FFP, and obtaining a magnetization vector M of Superparamagnetic Iron Oxide Nanoparticles (SPIOs) and a Point Spread Function (PSF) in combination with a Langevin function;
• S2, obtaining a signal feature on basis of a voltage signal of a detection coil of a Magnetic Particle Imaging (MPI) instrument with the non-ideal FFP and the ideal FFP magnetic field conditions;
• S3, performing integral transformation on the voltage signal collected by the detection coil of the MPI instrument on basis of the signal feature obtained in S2, to obtain a voltage signal of an equivalent ideal FFP;
• S4, averaging a moving speed of an FFP of the MPI instrument on basis of the signal feature obtained in S2, to obtain a moving speed of the equivalent ideal FFP;
• S5, obtaining an equivalent Three-Dimensional (3D) concentration reconstruction image on basis of the voltage signal of the equivalent ideal FFP obtained in S3 and a moving speed of the equivalent ideal FFP obtained in S4.