A method of nerve electrical stimulation by magnetic induction

The implantable electrical stimulator is usually not suitable for long term use because of its large size and short battery life, besides the magnetic stimulation can not provide deep nerve stimulation. Therefore, this paper developed a method of the electrical stimulation by using the magnetic induction. We implanted a small inductive coil which was connected with nerve electrodes. When the stimulation was applied, a coaxial coil containing a pulsed current was placed outside. So the electrical field evoking the nerve was formed because of the generation of inductive electromotive force in the inductive coil. Finite element analysis was used to analyze the electric field in the nerve and fiber model was used to predict the generation of action potential. This innovative method was applied on the sciatic nerves of rats. EMG was successfully recorded after the electrical stimulation by the magnetic induction. The results demonstrated that this new method was effective to stimulate the deep nerve.