MRI-Compatible, Transparent PEDOT:PSS Neural Implants for the Alleviation of Neuropathic Pain with Motor Cortex Stimulation

Abstract

Simultaneous monitoring of electrophysiology and magnetic resonance imaging (MRI) could guide the innovative diagnosis and treatment of various neurodegenerative diseases that are previously impossible. However, this technique is difficult because the existing metal-based implantable neural interface for electrophysiology is not free from signal distortions from its intrinsic magnetic susceptibility while performing an MRI of the implanted area of the neural interface. Moreover, brain tissue heating from neural implants generated by the radiofrequency field from MRI poses potential hazards for patients. Previous studies with soft polymer-based electrode arrays provide relatively suitable MRI compatibility but does not guarantee high-resolution electrophysiological signal acquisition and stimulation performance. Here, MRI compatible, optically transparent flexible implantable device capable of electrophysiological multichannel mapping and electrical stimulation is introduced. Using the device, neuropathic pain (NP) relief with a 30-channel electrophysiological mapping of the somatosensory area before and after motor cortex stimulation (MCS) in allodynia rats after noxious stimulation is confirmed. Additionally, artifact-free manganese-enhanced MRI of dramatic relief of pain-related region activity by MCS is demonstrated. Furthermore, artifact-free optogenetics with transgenic mice is also investigated by recording light-evoked potentials. These results suggest a promising neuro-prosthetic for analyzing and modulating spatiotemporal neurodynamic without MRI or optical modality resolution constraints.