Magnetic resonance compatibility of multichannel silicon microelectrode systems for neural recording and stimulation in the central nervous system

Magnetic Resonance (MR) compatibility of biomedical implants and devices represents a challenge for designers and potential risks for users. This work addresses this problem and presents the first MR compatible multichannel silicon chronic microelectrode system, used for recording and electrical stimulation in the Central Nervous System of animal subjects. A standard chronic assembly was tested on a 2 Tesla magnet to detect areas of concern and modified to minimize or eliminate susceptibility artifacts, tissue damage, and electrode displacement, maintaining good image quality and safety to the animals. Multiple commercial connectors were tested for MR compatibility and several options for reference electrodes were also tested to minimize image artifacts. The required circuitry to interconnect the MR compatible microelectrode with standard data acquisition systems was also designed and fabricated. The final design is fully MR compatible and has been tested on guinea pigs.