Ask the Audiologist

Completely in the Canal Hearing Aids

The past several years have seen a major milestone in the development of ever smaller hearing aids. These new hearing aids fit completely in the ear canal (see photos), providing a closer coupling to the eardrum and near invisibility to the casual observer. Potential benefits of these new CIC aids include a reduction of the occlusion effect, absence of wind noise, and the ability to use the telephone normally.

Sometimes there is confusion between the term "Canal Aids" and CIC aids. Canal aids are quite a bit larger than CIC aids and sometimes have problems with working their way out of the ear. Canal aids are the style you frequently see in mail order hearing aids, since they just are pushed into the ear canal opening.

Who can use them?
These new hearing aids are ideally suited for mild to moderate hearing losses, including individuals with fairly severe high frequency sensorineural losses. These aids are not suitable for all types of hearing loss and a thorough evaluation by an audiologist is advised before a CIC aid is purchased. Factors to be considered in addition to degree of hearing loss include the size of the ear canal, the aid's cost, and the patient's ability to handle small objects.

Who makes them?
CIC aids have been on the market for several years. One of the first CIC aids was the Philips XP Peritympanic deep canal CIC aid and later the Starkey Tympanette. (Neither of these are still available, but Starkey now has several CIC models, and most other major manufacturers have CIC aids available in various price ranges.)

Different brands of CIC aids have different circuits and case designs, and several brands even have remote controls for adjusting volume and programs (for music, for noisy rooms, for conversation, etc). Some brands, have digital signal processing CIC aids that automatically adjust all the parameters for you without any switches or remote controls. Not all ears or hearing losses are the same, thus some CIC aids will be more suitable than others in fitting a particular hearing loss.

Models of Digital Signal Processing CIC hearing aids are available from Widex, Siemens, Sonic Innovations, Starkey, Oticon, Bernafon, Rexton, and others.

What are the advantages?
Since CIC aids extend down into the bony portion of the ear canal, the occlusion effect may be reduced or eliminated. (The occlusion effect is the unnatural, hollow sound and/or plugged up sensation that some hearing aid users report.) Because of the proximity to the ear drum, less power is needed, reducing the likelihood of feedback. Since the outer portion of the typical CIC aid is well down in the ear canal, it is much less visible, and it is practically immune to the wind noises that bother conventional aid wearers. The outer ear is not blocked by any portion of the CIC aid, maintaining the ear's natural directivity for sounds. Finally, telephones can be used normally, without any special techniques.

Some important issues:
CIC hearing aids require more precision to fit than conventional aids. They fit deep down in the ear canal, making the impression taking process more exacting. It is important that the ear canal be examined for conditions that would make fitting these aids unwise. Because of the exact fit required to make these aids function properly, the patient can expect to return to the audiologist for several visits before the fitting process is complete. The audiologists, in addition to their comprehensive university training in audiology, attend special classes provided by the manufacturers to become qualified to fit the various brands of CICs. Like all hearing aids, CICs come with a 30 day adjustment period in most states, so users can test them in a variety of situations.

One of our CIC users, who has worn several styles and brands of hearing aids, said, "I'm so pleased, I wouldn't let you pry my new [CIC aids] out of my ear."