Development Of A Programmable Spinal Cord Stimulator With Wireless Communication And Power Transmission

Clinical studies have shown that spinal cord stimulation can promote recovery of walking function in patients with spinal cord injury, but the mechanism of its treatment still lack depth understanding which need for research in animal experiments, so a programmable spinal cord stimulator with wireless communications and wireless charging is designed to provide advanced research tools for animal experiments. Compared with our previous development of the stimulator which is disposable battery-powered, the new one has solved the limitations of battery capacity, and has reduced power consumption of the communication, so it meets the requirements of long-term implantation.The stimulator designed in this thesis consists of two parts, one is in body and anther is outside the body. One is an APP installed on one smartphone as the controller on which users can set stimulating parameters outside the body; another is a wireless energy transmitting means which is used to transmit energy to the spinal cord stimulator(SCS)inside the body. The SCS can receive stimulating parameters the APP transmitted via the Bluetooth low energy(BLE), and outputting a corresponding stimulation pulse. The SCS can output two-way balance pulse which width range is 400 ~ 4000?s(step 400?s), the amplitude range is 10 m V~ 10V(step 10 m V), and the frequency range is 1Hz ~ 200Hz(step 1Hz). Finally, based on the transmitting and receiving coils which has designed based on the principle of magnetically coupled resonance, wireless charging circuit and the battery detection circuit is designed, so that the lithium-ion battery of SCS which capacity is 8m Ah, can gain 2m A charging current from 10 cm diameter inner circle which is 3cm high from the transmitter coil, it means the design has solved the problem of implantable device's energy supply for long-term implantation.In this thesis, firstly, the research and development of the implantable stimulator of at home and abroad is introduced, and the spinal cord stimulation therapy and its application in terms of analgesia and rehabilitation of walking function are presented. Secondly, theoverall design of the SCS, and the hardware and software design of which each module are introduced. Thirdly, the paper give the prototype stimulator which is designed is testing, and having the wireless charging experiment, on the 5cm high space from the transmitter coil, the lithium-ion battery which is 8m Ah capacity is charged fully. Finally, a comparison of power, drive capacity and other parameters between the designed stimulator and the existing stimulator is given, it shown that the designed stimulator has lower communication, higher driver capacity, etc. So the new stimulator meets the requirements of long-term implantation.