BioBolt: Biomedical wireless sensor is minimally invasive as an alternative to craniotomy

While attending the MEMS Executive Congress in Scottsdale, AZ I met Dr. Andy Oliver, PhD. Andy is the Industrial liaison and principal staff scientist at the University of Michigan Center for Wireless Integrated MicroSensing & Systems or WIMS² as they call it.

The mission of the Center for Wireless Integrated MicroSensing and Systems (WIMS²) at the University of Michigan is to advance the design, fabrication, and breadth of the applications for sensor-driven microsensors and systems through research, education, and interactions with industry.

These technologies include: micro and nanoscale fabrication, micro-machined RF filters and resonators, packaging, power harvesting, low-power circuitry, and wireless interfaces with applications in biomedical devices, chemical and environmental sensors, and infrastructure monitoring. The applications' focus and interdisciplinary nature distinguishes WIMS² from other university research efforts. The relevance of this research is shown by the 12 start-up companies and 60 patents the Center has generated over the past 11 years. 

The following is courtesy of WIMS² regarding the biomedical device research done earlier this year.

In this work by Sun-Il Chang, Khaled AlAshmouny, and Euisik Yoon, BioBolt: a distributed minimally-invasive neural interface for wireless epidural recording has been designed and developed. The main purpose of this work is to optimize the trade-off between the quality of neural information and the invasiveness of the neural interface systems. In order to achieve this goal, the proposed system has introduced several innovations as follows: 

The signals epidurallay recorded from the surface of dura mater are transmitted through the skin (ISCOM) to the external station. To secure the long-term reliability for chronic monitoring, the whole system will be subcutaneously implanted inside the cranium to eliminate any possible infections from external environments. Furthermore, in contrast with other implantable ECoG systems where the operation of the craniotomy is required, the handiness of the bolt-shaped system concept can differentiate the proposed system from other existing systems by providing the simple and safe operation protocol of implantation and explantation.

Extreme low-power analog front-end including a low-noise preamplifier and analog-to-digital converter has been proposed to ensure a robust interface, because the neural potentials are vulnerable to external interference such as drift/offset from the cell-electrode interface and power line noise. With collaboration with Washington University, St. Louis, we successfully performed the in-vivo experiment with Monkey without the power-line interference. The epidural electrode has been placed on the surface of dura mater of the monkey and the neural activities from sixteen channels were recorded simultaneously as shown in Figure 1.

Figure 1: Sixteen channels simultaneously recorded showing neural activity in a monkey with the epidural electrode placed on the surface of dura mater

(Click on image to enlarge)