Softer, thinner and more compliant cochlear implants

Although cochlea implant (CI) technology has provided hearing and a better life for hundreds of thousands, it can be improved. The complex fine structure of the cochlea and especially its long, winding and narrow scala tympani (ST), with its fragile basilar membrane and thin soft tissue (10 – 100 µm), demands more delicate CI electrode arrays. Our vision is that softer, thinner and more compliant CI electrode arrays, made by our microfluidic stretchable printed circuit board technology, will reduce trauma and improve remaining hearing at the same time as they provide a better electrical stimulation of the cochlear nerve. The purpose with this research project is to study different means of manufacturing and implanting such electrode arrays, and evaluating them in vivo Guinea pig models.

The components will be made at the Division of Microsystem Technology and implantation and medical evaluation will be made at the Otorhinolaryngology and Head and Neck Surgery group, both at Uppsala University. The design and evaluation of the CI electrode array will be made together. There are three specific aims for the project, with focus on the soft, thin and compliant silicone based electrode array; the heterogeneous integration of thin Pt electrodes with hydrogels; and means for inner ear surgical handling of these very soft and compliant implants.

By fulfilling these aims, there should be conclusive results and a good understanding of the merits of the novel CI electrode arrays for clinical implementation.


The Swedish Research Council


2018 –2022

Partner organizations

  • Dept Materials Science and Engineering, Uppsala University
  • Dept Surgical Sciences, Uppsala University

Project leader

Klas Hjort, Microsystems Technology, Uppsala University

Project members

  • Hao Li, Otorhinolaryngology and Head and Neck Surgery, Uppsala University
  • Helge Rask-Andersen, Otorhinolaryngology and Head and Neck Surgery, Uppsala University

The first soft, thin and compliant array of three electrodes to be tested in vivo.
Last modified: 2022-03-04