Wireless Intracranial Pressure Monitoring System based on Multi-layer Printed Coil

This work proposes a wireless intracranial pressure (ICP) monitoring system based on a multi-layer printed coil (MLPC) inductive link. The system is composed of an implantable ICP sensor, a portable controller and a data management terminal. The ICP sensor in our previous work were powered by off-board coil, making the power supply the primary obstacle to implant miniaturization. This paper introduces an MLPC structure, and the corresponding model along with an inductive link based on it. The results show that an MLPC of the same size can provide $3 x$ quality factor of a printed spiral coil. PCB-integrated coil design reduces the size of the ICP sensor by 75% compared with previous work. The proposed ICP monitoring system achieves a 17 mm operating distance and a measurement resolution of $0.3 \mathbf{~ m m H g}$. Keywords-Intracranial pressure monitoring, multi-layer printed coil, wireless power transfer, implantable device