Completely-in-Canal (CIC) is a style of hearing instrument custom-made to sit entirely within the ear canal. This design makes the CIC one of the most discreet hearing aids available, appealing to people who may feel self-conscious about wearing a device. The physical design requires all necessary components to be miniaturized and housed in a small custom shell.
Physical Characteristics and Deep Canal Placement
CIC hearing aids are individually manufactured from a physical impression of the ear canal to ensure a precise, comfortable fit. The custom-molded shell extends deep into the ear canal, past the tragus (the small cartilage flap at the entrance of the ear). This deep placement allows the hearing aid to be virtually invisible.
All functional elements—the microphone, amplifier, microchip (signal processor), battery, and receiver (loudspeaker)—are packed into this tiny housing. The microphone is positioned at the opening of the device, just inside the ear canal entrance. This positioning takes advantage of the ear’s natural acoustics, a phenomenon known as the pinna effect.
The pinna effect refers to the natural way the outer ear collects and funnels sound waves toward the ear canal opening. Utilizing this process can improve the user’s ability to localize sounds. The receiver is placed close to the eardrum, allowing the amplified sound to interact more directly with the inner ear structures. The small size means the device uses a size 10 battery, which must be changed regularly.
Distinct Advantages and Practical Limitations
The primary benefit of the CIC style is its exceptional discretion, as the device is nearly unnoticeable when worn. This design also allows comfortable use with accessories like glasses, hats, or headphones, since no part rests behind the ear. Furthermore, the deep placement shields the microphone from open air, significantly reducing wind noise.
The miniaturization necessary for the CIC design introduces trade-offs in performance and maintenance. Limited space means these aids use small batteries that require more frequent replacement than larger styles. The small housing also restricts advanced features like directional microphones, which help focus on speech in noisy environments.
Maintenance is challenging because the device sits deep within the ear canal, making it highly susceptible to moisture and earwax buildup. Users must be diligent with daily cleaning to ensure the microphone and receiver ports remain clear. The small size can also make handling and battery changes difficult for individuals with dexterity or vision issues.
Determining Candidacy and the Fitting Process
Not every person with hearing loss is a suitable candidate for a CIC hearing aid; suitability depends on the degree of hearing loss and the physical anatomy of the ear. This style is recommended for individuals with mild to moderate hearing loss because the small components cannot provide the necessary amplification for profound cases. The ear canal must also be wide enough to accommodate the device shell and deep enough to conceal it entirely.
Acquiring a CIC device begins with a comprehensive hearing evaluation by an audiologist. If suitable, the fitting requires taking a physical impression, or mold, of the ear canal. This mold is sent to the manufacturer to custom-build the shell housing for the internal components. This tailored approach ensures the device fits perfectly, maximizing comfort and acoustic performance.