Fully implantable hearing aid one step closer

We are now one step closer to a fully implantable hearing aid, say scientists at Karl Landsteiner University of Health Science, Austria. Researchers performed the first-ever successful test on the implantable hearing aid, i.e., one that operates inside the human body.

The technology uses completely contact-free fiber-optic technology. The technology senses minuscule ossicle movements, i.e., tiny movements of a bone in the middle ear. It then uses those movements to stimulate the acoustic nerves.

According to the Austrian-Serbian team, the tests produced important findings on how to use the technology on human beings.

Hearing aids should help people hear. However, nobody should be able to see them. This is precisely what the fully surgical implantable heading device offers, i.e., discrete hearing.

Fully-implantable hearing aid
According to Elsevier.com: “To create an implantable hearing aid, the team devised a non-contact fiber-optic interferometric sensor, to serve as a microphone implanted inside the middle-ear.”

Hearing aid has microphones

The hearing aid has microphones which receive sounds. They then use a sophisticated process to transform the sounds into impulses for the acoustic nerves.

It is vital that a hearing aid works error-free inside the human body for several years. Unfortunately, it is only possible today to a very limited extent. Hence, there is currently a race to find new solutions.

Fiber-optic measuring technology – the solution

The Serbian-Austrian scientists believe that the use of fiber-optic measuring technology might be the solution. The technology in this hearing aid picks up vibrations from the ossicles.

The scientists wrote about their tests and research in the journal Biosens Bioelectron (citation below).

The quest for a fully-implantable hearing aid

Research team member, Prof. Georg Mathias Sprinzl, said:

“”Even state-of-the-art hearing aids often require parts outside the ear. This has many disadvantages for people who wear hearing aids: they can be stigmatised if the device is visible, parts of the ear often become inflamed and the wearer’s own voice can sound distorted.”

“Fully implantable hearing aids can overcome these problems – but the technology still needs to be fine-tuned. And that’s what we are working on.”

Prof. Sprinzl is head of the Ear, Nose and Throat Department at St Pölten University Hospital, Krems, Austria.

Further research required

In principle, this new hearing aid could operate inside the ear. It is also durable, i.e., it can operate for long periods.

The team says that measurements so far have showed that the system can distinguish between important sounds and background noise. They also said that they still need to improve this technology.

Although the test was successful, the scientists need to work on redesigning and miniaturizing the entire system. They also need to decrease the overall power consumption of the hearing aid, they added.


In-vitro and in-vivo measurement of the animal’s middle ear acoustical response by partially implantable fiber-optic sensing system,’ Djinović Z, Pavelka R, Tomić M, Sprinzl G, Plenk H, Losert U, Bergmeister H, Plasenzotti R, Biosens Bioelectron, 2018 April 30. DOI: doi: 10.1016/j.bios.2017.12.015.