New Chance for the Deaf and Hearing Impaired: LZH Improves Inner Ear Implants

Laser micro-structured surface of the cochlear implant (left: platinum electrode; right: silicon carrier)

A new micro-structuring process for the surface of cochlear implants is being developed at the Laser Zentrum Hannover e.V. (LZH) in cooperation with the ear-nose-throat clinic of the HannoverMedicalSchool (MHH). This structuring process aims at improving the function of these inner ear implants and thereby increase the hearing ability of people who are deaf or hearing impaired.

These implants use electric signals to stimulate the acoustic nerves in the cochlea. This project plans on using laser technology to structure the surface of these implants so that neurons can attach themselves more easily onto the implant, improving the transmission of the electric signals. At the same time, the growth of connective tissue will be reduced, since these cells affect the function of the electrodes negatively.

In order to achieve this goal, the LZH will use the extremely short pulses of a femtosecond (fs) laser to structure the surface of the implants, which consist of silicon and platinum. Using fs-laser technology, the surface can be structured without negatively influencing the conductivity or the biocompatibility of the implant.

The laser "cuts" 5 µm broad channels into the platinum electrode surface, making it easier for neurons to attach themselves onto the implant so that the stimulation of the acoustic nerve can be improved. At the same time, structuring of the surrounding surface can be used to hinder the growth of connective tissue.

First tests with cell growth experiments showed positive results. However, further tests are necessary before the micro-structured implants can actually be used in the human body. The long-term goal is to produce a cochlear implant that will improve hearing for many people.

The project is a cooperative effort between the ENT clinic of the Hannover Medical School, the Technische Universität Braunschweig and the Helmholtz-Centre for Infection Research. The project is supported by the German Research Foundation (DFG).

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Business Development & Communications Department
Communications Group
Michael Botts
Public Relations
Tel.: +49 511 2788-151
Fax: +49 511 2788-100

The Laser Zentrum Hannover e.V. (LZH) carries out research and development in the field of laser technology and is supported by the Ministry of Economic Affairs, Labour and Transport of the State of Lower Saxony (Niedersächsisches Ministerium für Wirtschaft, Arbeit und Verkehr).