Developing and Evaluating a Flexible Wireless Microcoil Array Based Integrated Interface for Epidural Cortical Stimulation

Abstract

Stroke leads to serious long-term disability. Electrical epidural cortical stimulation has made significant improvements in stroke rehabilitation therapy. We developed a preliminary wireless implantable passive interface, which consists of a stimulating surface electrode, receiving coil, and single flexible passive demodulated circuit printed by flexible printed circuit (FPC) technique and output pulse voltage stimulus by inductively coupling an external circuit. The wireless implantable board was implanted in cats’ unilateral epidural space for electrical stimulation of the primary visual cortex (V1) while the evoked responses were recorded on the contralateral V1 using a needle electrode. The wireless implantable board output stable monophasic voltage stimuli. The amplitude of the monophasic voltage output could be adjusted by controlling the voltage of the transmitter circuit within a range of 5–20 V. In acute experiment, cortico-cortical evoked potential (CCEP) response was recorded on the contralateral V1. The amplitude of N2 in CCEP was modulated by adjusting the stimulation intensity of the wireless interface. These results demonstrated that a wireless interface based on a microcoil array can offer a valuable tool for researchers to explore electrical stimulation in research and the dura mater-electrode interface can effectively transmit electrical stimulation.

Novel double anisotropic conductive flexible composite film endued with improved luminescence

“…Type I ACFs are conducting along the thickness direction of the membrane and insulated along the membrane surface. 5 This type of ACF has applications in smart card 6 and electronic fields. 7 On the basis of type I ACFs, type II ACFs are further developed and have different conductance along the two perpendicular directions of their surfaces.…”

Millimeter-sized battery-free epidural cortical stimulators

“…Preclinical work in rodents has shown battery-free cortical stimulation 27–29 but the stimulation amplitudes are too small to stimulate the human brain through the dura. The only large animal, battery-free epidural cortical stimulator the authors are aware of was reported in a feline model, but the translational misalignment of only ∼3 mm makes it difficult to achieve proper alignment in our use cases in the operating room (OR) or at home 30 .…”