Pure-tone audiometry. Hearing Systems. Photo: Joachim Rode.

Hearing aids fit for the future

Electrotechnology Sound Medicine and medico technology Hearing aids
New DTU research is paving the way for matching hearing aids more closely to user needs. The aim is for more people to be happy with their hearing aids—and actually use them.

Today, hearing aids are fitted based on a single test where you wear a set of headphones and raise your hands when you hear a beep in either one ear or the other. After that, setting up the hearing aid for optimum functionality depends on audiologist’s experience. Often, this is a lengthy process involving the user trying out the hearing aids at home and then consulting with the audiologist for adjustments. This often requires several appointments—and, sadly, often ends up with the user giving up and not using the hearing aids.

A DTU research team is seeking to base the initial set-up of hearing aids on a more accurate profile of the person’s hearing. Accordingly, their starting point is two scientific studies carried out in recent years involving 130 people with hearing loss undergoing extensive testing. Each of the studies included a comprehensive battery of tests taking between two and four hours to complete per participant, and which therefore produced a detailed picture of the reason for the different types of hearing loss, and how they are experienced.

"The better we understand patients and their hearing loss and the more insight we have into the way hearing aids reproduce sound, the easier it will be to make the right match."
Raul Sanchez Lopez

Four profiles from machine learning
“We’ve reviewed all the data from these earlier studies. We did this using machine learning methods, which helped us to define two different key parameters in relation to categorising hearing loss. We used those as a basis for defining of a total of four different audiological profiles, to cover everyone with hearing loss,” explains Raul Sanchez Lopez, a researcher at DTU Electrical Engineering.

 Each of the four profiles has a matching recommendation of the optimum setting for this category. For example, the priority for someone in one profile group may be only to be able to hear sounds from the person he or she is looking at—while people in another profile group want to be able to hear amplified sounds coming from the side and behind them too. These two settings are very different for hearing aids.

“We hope to be able to use two or three simple tests taking roughly half an hour to define the correct profile for the person with hearing loss. Against this background, the audiologist will then be able to set up the hearing aids so they operate as well as possible from the outset—and, we hope, be used instead of ending up in a drawer because they don’t do the job the user needs them to do,” says Raul Sanchez Lopez.

He hopes the new test and the four audiological profiles will be up and running in hearing-aid clinics within the next 5–10 years.

Best match by connecting to the hearing aid
Preparing the four audiological profiles is part of a major project, Better Hearing Rehabilitation (BEAR), with the participation of Aalborg University, the University of Southern Denmark, the University hospitals and the three Danish hearing aid companies Oticon, Widex and GN Hearing.

BEAR has received EUR 3,9 million (DKK 29 million) from Innovation Fund Denmark and is scheduled for completion in 2021.