Posted: August 15, 2014
University of Alberta researchers have developed an electrode array supported by a flexible base that can be used for both stimulation and recording of neurons in the brain and spinal cord (central nervous system), and in the peripheral nervous system. The design incorporates a silicon elastomer base with ultra-fine microwires which are coiled within the base to facilitate stretching and compression. The fabrication method allows for patient specific base thickness and curvature, and distinc electrode layouts.
Current arrays all feature a stiff base, which may contribute to the fact that most implanted arrays remain viable for only 1 to 2 years. Mechanical stresses generated at the interface between the array and the tissue in which the array is embedded may, over time, lead to increased encapsulation of the array, therby hindering the transmission of electrical signals. This problem is particularly sever in the spinal cord which undergoes considerable strain in torsion, bending, and twisting.
The present invention:
- reproducibly gives thin array bases with a modulus of elasticity and curvature mathing that of the spinal cord;
- integrates coiled lead wires for stress relief which could increase the long-term chronic implantation applicability of this neuroprosthetic.
Microelectrode arrays are a primary component of implanted neuroprosthetic interfaces used to stimulate the nervous system in order to restore function after neural injury or disease. The compatibility between the present invention and the spinal cord should increase the long-term chronic implantation applicability of the device. This in turn increases the clinical viability of intraspinal implants.