Hybrid multimodal Deep Brain probe (DBS array) for advanced brain research

Abstract

Clinical trials have recently shown that Deep Brain Stimulation (DBS) can be applied to treat psychiatric disorders (e.g. Parkinson's disease, depression or obsessive compulsive disorders (OCD)). However, the underlying mechanisms of these disorders, as well as the influence of electrical stimulation remain not fully understood. We present a hybrid multimodal deep brain probe made out of a thin-film polyimide electrode and flexible silicone rubber substrate. The engineered combination of two technologies resulted in a device as flexible as commercial DBS probes, but including the benefits from thin-film technology such as higher contact density, high resolution in fabrication and capability of applying various coatings for specific applications. Preliminary studies showed that the concept of a hybrid probe is effective and promising. The prototyped samples were stressed mechanically on the basis of bending tests for implantable medical devices (EN 45502-2-3) in which, no failure was observed even after 150,000 bending cycles and storage in saline solution over 150 days. Usage of ceramic micro-adaptors allowed a stable mechanical decoupling between the wires and the thin-film device. Implementing biosensors into the deep brain probe, i.e. electrochemical sensors to monitor neurotransmitters, can be one of the possibilities provided by the proposed probe. High channel counts as well as feasibility to perform instantaneous monitoring of neurological event is distinguished as a key point towards addressing many unanswered questions, e.g. raveling the underlying neurocircuitry of psychiatric diseases, and hence, paving the way for more efficient treatment approaches.