By Brooke Struyk
Edited by Nataliya Brantly
Abstract:
Hearing loss affects a large portion of the global population, yet the prices for hearings aids continue to increase. With quality devices costing an upwards of $2000 per pair, and lasting between three to seven years depending on the model, access to these technologies has become more unreachable [1]. Over-the-counter hearing aids cost $100 and more, depending on the manufacturer. However, people with mild to severe hearing loss would not be able to use such devices [2]. Open-source hearing aids could be an effective alternative to current FDA-approved hearing aids. Open-source hearing aids not only offer a more affordable alternative but also allow patients to customize and create their own unique devices. This may include adjustable sound profiles, specific molding to the ear, aesthetic modifications, etc. This blog post aims to discuss open-source hearing aids, their pros and cons, and how they can be used in the future for the advancement of technology in medicine. With the new technological advancements and developments in Artificial Intelligence (AI), the idea of patients being involved with creating their own devices may lead to a better and more inexpensive direction for the healthcare field.
Keywords: open-source technologies, user-friendly design, customization, do-it-yourself (DIY), hearing aids.
Introduction
Hearing loss is a significant issue in the US and globally. Today, about 20% of the global population or 1.4 billion people live with hearing loss [3]. Of those 5% or 435 million people require rehabilitation to help with their hearing loss. In the United States 1 in 8 people ages 12 and older have hearing loss in both ears, and as of 2022, 1 in 25 Americans are reported to use hearing aids [4]. The average price of hearing aid in the US costs $2500 per device [5]. Depending on the person’s health insurance, the cost coverage might include only a portion of each hearing aid. Health insurance may also cover balance tests or hearing visits. Medicare specifically does not cover anything regarding hearing aids. In six US states, it is mandatory for adults to have health insurance coverage for hearing aids; however, in the other 44 US states, one must rely on their insurance coverage or pay out of pocket to cover their hearing aid [5]. Hearing aids are regulated by the FDA and require a prescription from a medical care provider, a hearing exam, and a fitting by an audiologist [6].
People with mild to severe hearing loss rely on the proper examination, fitting and access to the hearing aids. People with mild to moderate hearing loss may also require hearing aids. In this case over the counter (OTC) hearing aids would be a suitable and a more affordable option. OTC hearing aids are subject to the FDA regulation but do not require additional examination or fittings, which cuts down on the extra cost of doctor’s appointments and travel. They usually come pre-programmed or have basic self-adjustment options that are based on self-assessment results[7]. Although there are limitations on how customizable the device can become and if it is a sustainable long-term option, it is a recommended affordable option for people with mild hearing loss. Unfortunately, people with severe hearing loss cannot use these OTC devices.
About 8% of the US population did not have health insurance coverage in 2024 [8]. This means that there are many people with hearing loss that need access to medical devices but might not be able to afford them. Thus, it is important to consider open-source hearing aids as a viable and needed solution. Open-source software is code that is open to everyone and can be accessed, modified and used by anyone. The hearing aid community started working on open-source hearing aid software in response to the recent increase in hearing aid and insurance prices. The next few sections explain how hearing aids work, what open-source hearing aids are, real life applications of the open-source hearing aids, existing gaps within the space, and what the future holds for open-source hearing aids and other expensive devices that may be able to create such alternative solution.
How do hearing aids work?
In their simplest form hearing aids amplify sound. A computer chip in the device converts the sound picked up from the device’s microphones into code that is analyzed and then converted back to sound waves and delivered to the person’s ears [9]. The code is specifically set for the level of hearing loss and the level of sound in the environment. Hearing aids are also battery powered and in more advanced devices, the hearing aid is rechargeable. Hearing aids work best for people with sensorineural hearing loss [10]. This hearing loss is caused by damage to the inner ear or auditory nerve. Such damage might be caused by aging, disease, infection, loud noises, or certain medications. The device itself can be molded to the ear based on user’s preference and can usually last up to 6-7 years before the user might require a new device [4]. It is important to note hearing aids are used for people with low, moderate and extensive hearing loss. People with more extreme or complete hearing loss may require other technologies, such as a cochlear implant.
What are open-source hearing aids?
Open-source hearing aids provide a cheaper and more individualized way to create and code hearing aids. The objective of the open-source hearing aid websites is to create very clear and structured guidelines to follow. The coding section includes many libraries that can be downloaded. The libraries provide ready-to-use code a person can take to input into their device without extra steps or fixes. Each device can be further personalized based on to user’s preferences. It should be noted that understanding how GitHub works and having basic coding skills may be best to help navigate the platform. On the other hand, the hardware guidelines are included online with instructions regarding what to buy with embedded links and how exactly to use and put together each component.
One such open-source hearing aid platform is the Open Master Hearing Aid (openMHA). openMHA was founded in Germany and has since been accredited by the NIH as a resource to be used if looking for an open-source software platform [11]. The coding languages used for openMHA are MatLab and Linux. This means that everything that can be downloaded from openMHA libraries, including the instructions, are all only geared towards specific software. When looking at the pricing model for both MatLab and Linux platforms, Linux is free and may be the “better” option. The openMHA also has a forum where people who are creating these devices can use and write comments or questions. On GitHub people also respond to coding questions and issues that come up to help with the building of the device as well.
Another open-source website is Tympan. Tympan sells hardware for their devices and provides a forum for their open-source code to be accessed. Something that differentiates openMHA and Tympan is that Tympan uses C and C++ for their coding site which is typically used for imbedding systems. This means that the libraries used on Tympan cannot be used with openMHA due to the different platforms used. Tympan also sells kits that are used for the coding they design. In the kits there is a 3D case with a Tympan Audio Board, a modified Teensy (a USB based microcontroller), a USB Cable, and a rechargeable Li-ion battery [12]. The entire process is very easy once one downloads the initial software. The Tympan Rev F kit is $329.99, the smaller earpieces are $475, and the Tympan AIC Shield is $99 [11].
GitHub is another source that can be used for open-source code. There are many different forums within GitHub that have engineers online who can help people in real time if there is an issue or if they have a question about the coding or the recommended hardware. Tympan’s website has links to GitHub. One can find all the necessary information about setting up their kits on GitHub where they can also ask specific questions and troubleshoot their device. GitHub is also a great place to find other coding projects and ideas for such devices.
Real life application
The Tympan site has a community project page where people who have made devices can post their creations. One such post was from a woman who made her device look like cat ears [13]. This way she covered the hardware of the device while also using the headband as a bone conduction speaker. Such speakers transfer sounds into vibrations. When the bands are placed next to the ears, the sound will be transferred to the place in her ear that is healthy, the cochlea, and skips over the place that is injured, the ossicles [13]. The case study proves that open-source hearing aids do work and can be personalized for people who may not be able to access or use hearing aid devices on the market. It also highlights the importance of such websites like Tympan and demonstrates that people do need open-source devices and are willing to put in the time to code and create them.
Georgia Tech researchers are working on a way to send ultra-low-cost hearing aid devices gear towards older adults in low-income areas [14]. Older adults with hearing loss tend to see a faster cognitive decline and this device hopefully provides an affordable option to the elderly early on. Researchers are working to meet the World Health Organization’s target for mild to moderate hearing loss with a device worn similarly to the one picture in Figure 1 below [14]. Although this research is targeting mild to moderate hearing loss, this research is a great way to further understand the concept of open-source hearing aids. This research also highlights the idea that such devices can be used for people of any age, and furthering the idea that since society has technology, access to it is very important.
Figure 1: Example of a person wearing an alternative hearing device [15]
Existing gaps
Open-source hearing aids are still not widely used due to a number of gaps: cost, size, and knowledge. The price of the hardware that is sold by businesses like Tympan and openMHA is somewhat still costly. The cost of the open-source hearing aids when compared to the FDA-approved hearing aids is still lower, however, it is not free and can be prohibitively expensive for many. Such open-source devices cannot truly be free because there is the initial cost of the hardware. The second issue is that the hardware is rather big and bulky. Visually, depending on one’s hearing aid, the commercial devices can be very small, hardly seen and rather discreet. The open-source devices are visually not very appealing and include more weight the user must carry around. Visual examples of open-source devices and their components are illustrated in Figure 1 above and Figure 2 below.
Figure 2: Example of the Tympan device system [16]
The lack of visual appeal and the extra weight might be a barrier and might prevent someone from trying to make their own device they might require due to lack of access to commercial options. Additionally, there is also little to no press coverage about such open-source devices as an effective option for the patient. The public might not know that one can create their own device to help with their hearing needs. Not many people have posted and shared information about the device they have created. This lack of publicity and low level of engagement may be a deterrent for many who have the need for such device but might not know where to go to access information and get support.
Another gap that may need to be investigated for open-source hearing aid devices is the idea behind the post-market cybersecurity issues. Due to the code being open source one may question if the device would be easier to hack into than a regular commercial hearing aid. A hacker has the potential of turning the device all the way up and permanently ruining user’s ear drums. This can be true with both devices and is important to look at in further research. The FDA does not regulate and surveil post-market performace of any medical device in regard to cybersecurity threats. Although one’s medical device being hacked into may seem like a very distant and obscure idea, it is a real issue and something that may need to be tested and researched further, especially for devices that use open-source code. As more people use open-source devices and start to advocate for them, more individuals take them seriously put put a spotlight on such much-needed individualized medical devices.
Conclusion
Hearing aids are an essential technology that can help make individuals lives easier. Such devices are an investment in healthcare and one’s quality of life. However, when one cannot afford to access such technology commercially, there must be an alternative option available. Over-the-counter hearing aids are available as an affordable option for patients with mild hearing loss, but there is no such option on the market targeting patients with severe hearing loss at an affordable price. Open-source hearing aids should be promoted, discussed and advocated for more broadly as an available option so more people that need them might consider them as a viable solution. Medical journeys and lived experiences are not linear and not every commercial medical device is going to help everyone the exact same way. Open-source technologies and DIY medical devices are an alternative option that adds flexibility, customization and can be a better fit for individual’s lifestyle and health needs. Currently, 20 US states require insurance to cover a portion of children’s hearing aid cost. Six of those states are required to also cover a portion of hearing aid costs for adults. This raises the need for additional laws and regulations that improve the affordability and accessibility of hearing aids for both children and adults. For adults who suffer from hearing loss, additional regulatory safeguards should be put in place to close the gaps and address the issue with greater access to hearing aids. Support for innovation, especially one that promoted greater access at lower cost, should be embraced even if the source of it comes from alternative sources.
Works Cited:
[1] T. Tomiyoshi, “Doctor pioneers pacemaker procedure in kids,” UCDavis Health, 2022. [Online]. Available: https://www.dicardiology.com/content/doctor-pioneers-pacemaker-procedure-kids.
[2] A. I. Adam Rowden, Danielle Dresden, Suzy Davenport, “Hearing Aid Cost and Pricing: Prescription and OTC Options,” Medical News Today, 2023. [Online]. Available: https://www.medicalnewstoday.com/articles/cost-of-hearing-aids.
[3] “Deafness and hearing loss.” https://www.who.int/health-topics/hearing-loss#tab=tab_1.
[4] “Quick Statistics About Hearing, Balance, & Dizziness.” National Institute on Deafness and Other Communication Disorders. https://www.nidcd.nih.gov/health/statistics/quick-statistics-hearing.
[5] A. Abram Bailey, “Paying for Hearing Aids with Health Insurance,” 2024. [Online]. Available: https://www.hearingtracker.com/hearing-aid-insurance-coverage.
[6] A. I. Adam Rowden, Danielle Dresden, Suzy Davenport. “Hearing Aid Cost and Pricing: Prescription and OTC Options.” Medical News Today. https://www.medicalnewstoday.com/articles/cost-of-hearing-aids (accessed.
[7] A. D. Angela Lalla. “OTC Hearing Aids vs Professionally Fitted Hearing Aids.” Audiologic Solutions. https://www.audiologicsolutions.net/blog/otc-hearing-aids-vs-fitted-hearing-aids.
[8] “The State of Health Insurance Coverage in the U.S.” https://www.commonwealthfund.org/publications/surveys/2024/nov/state-health-insurance-coverage-us-2024-biennial-survey.
[9] M. C. Staff, “Hearing aids: How to choose the right one,” Mayo Clinic. [Online]. Available: https://www.mayoclinic.org/diseases-conditions/hearing-loss/in-depth/hearing-aids/art-20044116.
[10] “Hearing Aids,” Cleveland Clinic. [Online]. Available: https://my.clevelandclinic.org/health/treatments/24756-hearing-aids.
[11] H. Kayser, “Open community platform for hearing aid algorithm research: open Master Hearing Aid (openMHA),” National Library of Medicine, 2022. [Online]. Available: https://pubmed.ncbi.nlm.nih.gov/35465173/.
[12] Tympan. “Getting Started with Tympan Rev D.” GitHub. https://github.com/Tympan/Docs/wiki/Getting-Started-with-Tympan-Rev-D (accessed.
[13] “Transforming cat ears to a hearing aid.” Tympan. https://shop.tympan.org/pages/tympan-nya.
[14] G. I. o. Technology, “Ultra-Low-Cost Hearing Aid – $1 Worth of Open Source Parts – Could Address Age-Related Hearing Loss Worldwide,” SciTechDaily, 2020. [Online]. Available: https://scitechdaily.com/ultra-low-cost-hearing-aid-1-worth-of-open-source-parts-could-address-age-related-hearing-loss-worldwide/.
[15] IEEE, “A user wearing the OSP wearable platform. The two hardwarecomponents shown are the behind-the-ear receiver-in-canal (BTE-RIC)transducers and the Processing and Communication Device (PCD, ed, 2019).
[16] A. P. o. M. o. Acoustics, “The Auditory Research Platform (ARP) 3.1. The ARP earpieceseach feature an outer-ear microphone, a high-attenuation ear tip, and an in-earspeaker while the ARP software framework is hosted on an external personalcomputer (PC).”, ed, 2021.