Researcher and senior implant audiologist Dr Cathy Sucher explains what GPs need to know about cochlear implants.
We know that hearing loss affects one in six West Australians, increasing to one in four for people over 65 years of age. The impact of hearing loss is far-reaching, with a significant effect on relationships, mental health and physical wellbeing.
And yet, many people with hearing loss remain untreated despite showing symptoms.
Many GPs regularly encounter hearing loss in their daily practice, and they play a vital role in ensuring timely referral to treatment.
Hearing aids help many people, but a cochlear implant may give better clarity and volume needed to understand speech as hearing loss progresses.
Cochlear implants are life-changing devices that can help people hear sounds they no longer hear with hearing aids.
What is a cochlear implant?
The implant is a sophisticated electronic medical device that bypasses damaged sensory hair cells within the cochlea (inner ear) to directly stimulate auditory nerves. It consists of two parts:
- The external processor collects the sound, converting it into a radio frequency signal that is sent through the skin to the internal part of the implant.
- The internal implant consists of the receiver-stimulator and electrode. The electrode is inserted into the cochlea and provides electrical stimulation to the auditory nerve which, in turn, takes the sound to the brain.
When is it an option?
If your patient wears hearing aids and is still struggling in specific listening situations ask them if they:
- find it hard to hear on the phone
- often ask people to repeat themselves
- find it difficult to follow a group conversation and avoid social situations
- struggle to understand what is being said if people are not facing them
If they answer yes to one or more of these questions, then a cochlear implant might be life-changing for them.
Hearing aid vs cochlear implant
Hearing aids and cochlear implants both improve hearing for people diagnosed with sensorineural hearing loss when there is damage to the hair cells in the inner ear.
A cochlear implant is surgically implanted by an ENT surgeon, programmed by an audiologist. Hearing aids are fitted by an audiologist and can be removed, whereas with cochlear implants, only the external processor can
be removed, not the implant.
Hearing aids amplify sounds while cochlear implants stimulate the auditory nerve to provide sound sensation.
Cochlear implants use electrical signals, whereas hearing aids use acoustic signals.
Improved outcomes
We have seen significant improvement in hearing outcomes for people who have transitioned from bilateral hearing aids to using a hearing aid and a cochlear implant in opposite ears.
These include a better understanding of speech, hearing in background noise, ability to hear on the phone, improved appreciation of music and ability to understand television and radio.
Research has shown that at 3-12 months post-implantation, 82% of recipients score above 90% on tests of sentence understanding, which is a significant improvement.
Only 10% of people who could benefit from a cochlear implant have one.
Research has highlighted a range of barriers to cochlear implantation, including a lack of knowledge about cochlear implants and uncertainty surrounding referral pathways, surgery and outcomes.
We know that GPs can help their patients overcome these barriers through confident referral of potential candidates. Additionally, concerns about the cost of the device is often a barrier, but there are funding options available for people who fit the candidacy criteria.
When to refer
Gone are the days when candidates for cochlear implants were limited to people with bilateral severe hearing loss.
The criteria have expanded to include patients with asymmetrical hearing losses and single-sided deafness. These implant recipients are achieving improved localisation of sound, better hearing in noise and reduced listening fatigue post-implantation.
There is now no upper age limit for candidacy. Many of recipients are in their 70s, 80s and even older. At this age, people enjoy communication and interaction, watching television, and this is when they require optimal hearing. Research shows that it is never too late to treat hearing loss to slow down dementia and reduce mental health issues, anxiety and loneliness.
GPs should also be on the lookout for patients wearing hearing aids but still experiencing difficulties, especially in challenging environments such as background noise or phone conversations. These patients may benefit from a cochlear implant and should be referred to an implant audiologist.
Referring for a cochlear implant can be done by sending a referral to an implant clinic or an ENT surgeon.
ED: Dr Sucher is a researcher and audiologist at the Ear Science Implant Clinic. The author acknowledges the contribution of senior implant audiologist Ronel Chester-Browne in the writing of this column.