Patent ID: 11914011
Assignee: BEIJING UNIVERSITY OF AERONAUTICS AND ASTRONAUTICS
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 8:
9. A handheld MPI method based on FFL rotation, implemented through the handheld MPI system based on FFL rotation according to claim 1, and comprising:
S10: inputting the direct current to the runway-shaped coil of the gradient module to generate the gradient field on a surface of the handheld MPI system; and generating, by combining the strip-shaped permanent magnet of the gradient module, the gradient field with the FFL in a vicinity of a surface of the excitation coil and the reception coil of the excitation module;
S20: inputting a high-frequency sinusoidal current to the excitation module to generate a high-frequency excitation field in a field of view of the handheld MPI system; and exciting magnetic particles in the FFL to generate a magnetization response voltage signal;
S30: filtering and amplifying, by the control and signal processing module, an induced particle signal, and performing fast Fourier transform on a time-domain signal to obtain a spectral sequence of the induced signal;
S40: operating the rotation module to simultaneously rotate the gradient system and the cooling system by a set angle, such that the FFL and the gradient field are rotated around the z-axis as a rotation center; and repeating steps S10 to S30 until the rotation module rotates in reverse back to an initial position after a 180° rotation scan; and
S50: performing, by the image reconstruction module, centralized processing for all spectral sequences generated after 180° rotation scans of the rotation module to construct a system measurement matrix; and calculating, based on frequency-domain signals at different rotation angles, a spatial concentration distribution of the magnetic particles, thereby achieving reconstruction of the two-dimensional image of the magnetic particles.