An implantable remedy is being developed by researchers from Harvard Medical School and École Polytechnique Fédérale de Lausanne (EPFL), Switzerland, to improve sound perception for patients with damage to the inner ear or auditory nerve.
Unlike available auditory brainstem implants, the new neuroprosthetic device is sufficiently elastic to conform to the curvature of the auditory brainstem, supporting the transmission of electrical signals required to restore some sense of hearing. The device is intended to treat deafness in patients who are not candidates for cochlear implants.
The elasticity of platinum electrode arrays housed in silicone is realized with the traditional Japanese paper-cutting technique called kirigami. After Y-shaped patterns are etched into metallized plastic components, methods usually associated with integrated circuit microfabrication are used to machine the metal at the micron scale, forming a compliant and conductive electrode implant. The kirigami method has also been applied by University of Michigan researchers in the development of an electronic sensor patch to measure the range of motion of hard-to-assess regions of the body.
The conformable electrode implant has been successfully tested on mice, and a version scaled for human use and in a form compatible with current surgical techniques has been produced.