Hearing Care Associates
A Division of Fritsch Otology

TYPES AND CAUSES OF HEARING LOSS

Conductive Hearing Loss
A conductive hearing loss is caused by a problem with the outer ear canal and/or the structures of the middle ear. Sound is unable to effectively reach the inner ear. Some of the causes of conductive hearing loss are: a buildup of wax (cerumen) in the ear canal, a lack of ear canal formation (atresia), a hole (perforation) in the eardrum, fluid in the middle ear space, a growth in the middle ear space, or a problem with one of the three middle ear bones. Most conductive hearing losses can be medically or surgically treated and may not necessarily be permanent. If, for some reason, the hearing loss cannot be corrected, hearing instruments most often provide significant hearing benefit.
Sensorineural Hearing Loss
The majority of hearing problems result from damage to the inner ear or the auditory nerve. The inner ear contains tiny hair cells that convert sound vibrations into electrical signals that are received by the auditory nerve. These tiny hair cells can bend or even break due to: exposure to very loud noises or prolonged exposure to loud, continuous noise levels, genetic disposition, virus infections of the inner ear, certain medical treatments such as chemotherapy and radiation, head injury, and with age. People with sensorineural hearing loss often experience difficulty with the clarity and understanding of speech particularly in the presence of background noise. Certain high pitch sounds such as birdsongs and childrens’ voices disappear. This type of hearing loss is permanent and is greatly helped with the use of hearing instruments. More than 90% of all hearing aid users have sensorineural hearing loss.
Mixed Hearing Loss
This type of hearing loss is caused by a combination of problems stemming from both the middle ear and the nerve of hearing in the inner ear. For example, an individual can have both a noise-induced hearing loss as well as a perforated eardrum (tympanic membrane). This combination of a sensorineural and a conductive component is a mixed hearing loss.

THE SOLUTION – Hearing Aids

Behind-the-Ear

Behind-the-Ear

* Hearing aid is housed in a case that fits behind the ear
* Custom ear mold is worn in the ear to direct sound into ear and hold aid in place
* Suitable for almost all types of hearing loss (mild to severe)
Receiver-in-the-Canal

Receiver-in-the-Canal

* The housing behind the ear in smaller due to the receiver being placed directly into the ear canal with soft dome.
* Leaves the ear open reducing the “plugged-up” feeling
* Suitable for mild to moderately severe losses

Full Shell in-the-Ear

Full Shell in-the-Ear

* Custom made to fit directly into the bowl of the ear
* Inserting of aid easy for almost all levels of dexterity
* Suitable for mild to severe losses
Completely-in-the-Canal

Completely-in-the-Canal

* Custom mode to fit deeply within the ear canal
* Least visible style of hearing aid
* Reduces wind noise due to placement deep within ear canal
* Suitable for mild to moderate losses
In-the-Canal

In-the-Canal

* Custom made to fit directly into the ear canal
* low visibility
* Smallest size available that allows for directional technology
* Suitable for mild to moderately severe losses
Cros Bicros Hearing Aids

Cros Bicros Hearing Aids

* Suitable for individuals with normal hearing or aidable hearing in one ear, and very little or no usable hearing in the other ear
* Hearing aid is worn on the better ear and an additional microphone is worn in the unaidable side

Other Hearing Systems

Cochlear Implant
Persons with a significant level of hearing loss or who have never heard before may benefit from an electronic device called a cochlear implant. It consists of two major components; the sound processor and the receiver-stimulator. Sound waves are passed through the sound processor microphone. These sound waves are converted into detailed digital information which is transferred to the implant just under the skin and with a wire electrode into the inner ear. Electrical signals are sent to the inner ear to the fibers of the nerve of hearing in the cochlea and then to the brain where they are interpreted as sound.
Implantable Bone Conduction Device

Whereas traditional hearing aids send the amplified sound waves through the middle ear to the inner ear; bone conduction hearing devices send the sound vibrations directly to the inner ear through the skull bone. An implant is surgically placed into the bone behind the ear. Once the surgical site heals and the bone bonds with the implant, a sound processor is attached externally via an abutment or magnet. This device is recommended for a select group of users.