"My hearing aids don't stay in my ears," he said, in the first rehab session after I fitted his Phonak Paradise P90 about 2 weeks ago in Bromley, Kent.
Hearing aids retention is one of the top 3 reasons why patients stop using their hearing aids, well, based on my own personal experience. The other two common complaints are "unnatural sound of the hearing aids", and "the aids whistling all the time". One in every 4 hearing aids finds its way into the drawer.
Hearing aids in essence are amplifiers. Tiny discrete high-tech amplifiers receive the sound in their microphones and pump the amplified sound into your ear canal. The position and stability of the part that goes in the ear are critical to the sound quality and comfort of the patient, hence to the retention of the aids, and the engagement of the wearer.
I'd be able to discuss this topic better if I split the discussion based on the type of your hearing aids:
BTE and RICs
The behind-the-ear (BTE) and the receiver-in-canal (RIC) type hearing aids often use a little silicon dome that goes in your ear canal and creates a passive seal against the inner wall of your ear canal. The dome usually is positioned about 10-12 mm from the entrance of your ear canal. Your audiologist picks the right dome size based on how wide or narrow your ear canal is. First-time users of hearing aids feel a bit weird in their ears. When I place the dome in their ear canal I usually advise them "This little silicon/plastic dome is now being placed in your ear, so, it should feel different, but it shouldn't feel painful or even uncomfortable."
The right dome - I try my best to make sure that the dome is the right size, not too tight, and not too loose. The feel of the dome in the patient's ear canal is crucial for the retention of the hearing aid and the engagement of the patient. So I spend enough time picking the right shape dome, and also the right dome size. Domes come in different shapes based on the manufacturer of the hearing aids, but usually, there is enough variety of the domes within the offering of each brand.
The shape of your ear canal - Unlike the general belief that the ear canal is like a straight pipe from your pinna straight up to your eardrum, the shape of the ear canal can be very different from person to person. Often the ear canal is upward and as goes inside it turns backwards. The shape of the ear canal is also another factor in the retention of the dome. Again the choice and the size of the dome can mitigate the retention issues to some extent.
The length of the thin tube - The length of the thin tube (in the case of BTEs) and the wire to the receiver (in the case of RIC) could also make the dome come out. Remember that as we speak our facial muscles move and if the wire or the tube connecting the case of the hearing aid (that’s located behind your ear) to the dome is too short it simply pulls out the dome As we speak or we eat food.
What if the dome and the wire are the right ones but still my hearing aids don’t stay in my ears?
If the shape and the size of the dome are right and if the length of the receiver wire is good your audiologist could suggest using the retainer wire (or lock) to hold the domes in Place. The retainer wire is a small piece of plastic wire that is connected to the dome or the receiver and springs inside your concha bowl.
How else I can keep the hearing aids dome in my ears?
Depending on the spectrum and severity of your hearing loss, your hearing care professional may suggest making a pair of canal moulds for you. The canal moulds (see the below picture) are made based on the impressions taken from your ear canal. They are made of acrylic or silicon (for better grip) and encapsulate the receiver. Extended length of the canal mould helps with their retention in your ear canal. Ultimately any other types of earmould such as skeleton, half or full shell could help retention of the dome or receiver in your ears.
ITE/ITC/CIC
The in-the-ear (ITE) or complete-in-canal (CIC) types of hearing aids are made based on the impression that we take from your ear canal. The custom aids usually have a better seal and retention in the ear, simply because the body of the hearing aid has much bigger surface contact with your ear canal. See below Phonak Virto M90 ITC as an example.
But still, there are cases that the patient has a retention problem with his or her ITE, ITC or CIC hearing aids. Here are the options that I might consider:
a. Is the hearing aid deep enough? If not I’ll make a fresh impression and order a new custom hearing aid that is deeper in the ear canal.
b. Silicon coating - Most of the hearing aid suppliers do accept having a silicon coat on the part of the body of the hearing aid that goes in the ear canal. This trick increases the friction factor and there we go.
Hearing aids are tech-wears that the users wear for the good part of their days so in addition to sounding clear and natural, they must be comfortable to the extent that after a few minutes, the wearer should start forgetting that they are in his/her ear canal.
If your hearing aids are not comfortable or keep piping out you should definitely see your audiologist.
