Design and optimization of wireless powered brain photodynamic therapy

Photodynamic therapy (PDT) is a safe treatment technology to treat malignant brain tumor, using laser to irradiate diseased tissue in the brain to treat malignant brain tumor. This paper designs the implanted miniature spiral receiving device (MSRD) operating at 796 kHz that receives transmitting coil (TX) energy through the resonant coupling power transmission (RCPT) to charge the Micro-LED (ML). The current voltage gain K
_u
, current gain K
_i
and output power P
₂
can be expressed function of the coupling coefficient, the quality factor and the resonant frequency. The optimized system is utilized a ferrite magnetic shielding physical model. Electromagnetic field simulation through the finite-element method (FEM) is done to obtain the magnetic field intensity distribution of energy transfer process and efficiency change, respectively. In addition, the influence of electromagnetic environment on human brain is analyzed by simulation. Both simulation results demonstrate that the proposed strategy can improve the output power by 1.28 times and transfer efficiency by 1.12 times compared with the pre-optimized system, which is verified by the experimental results.