Methods and systems for measuring tissue impedance and monitoring PVD treatment using neuro-implants with improved wireless powering are disclosed. In some embodiments, an implanted device including a wireless energy receiver, a demodulation circuit, and electrodes may be configured to received modulated energy from an energy transmitter. The implanted device may convert the energy to an electrical voltage to be applied to tissue to adjust the tissue's impedance. The tissue impedance may be measured with a computing system by receiving and processing an energy signal emitted/produced in response to the electrical voltage applied by the implanted device. In some embodiments, improved microwave powering schemes may be utilized to power the implanted device. In some embodiments, improved ultrasound powering schemes may be utilized to power the implanted device. For example, energy transfer efficiency from different transmitters may be evaluated to select for energy transmission the transmitter that yields optimal energy transfer efficiency.