Flexible Photovoltaic Neurostimulator for Analgesia

Chronic neuropathic pain remains a significant clinical challenge, often requiring prolonged opioid use and exposing patients to associated complications. Current nerve electrical stimulation (ES) techniques show promise for analgesia but are constrained by their invasive nature and the potential risk of iatrogenic nerve injury. In this study, a novel approach is introduced to managing chronic pain through the development of a fully implantable, wireless, and self-adaptive photovoltaic neurostimulator (PVNS). This innovative device combines flexible, self-rolling cuff electrodes with biocompatible flexible Cu(In,Ga)Se₂ (CIGS) thin-film photovoltaics, enabling near-infrared (NIR) light-triggered nerve ES. In vivo neuralgia models demonstrate significant analgesic effects, while mechanistic studies reveal the involvement of inflammatory pathway regulation and modulation of transient receptor potential vanilloid type 1 (TRPV1). The PVNS eliminates the difficulty for tethered stimulation and reduces the risk of peripheral nerve injury, offering a groundbreaking and minimally invasive solution for the treatment of chronic neuropathic pain.