GLOSSARY OF TERMS

If you have a child with microtia & aural atresia here is an explanation of some terms that you may come across:

Audiogram - a graphical representation of how well a person can hear. The results a hearing test in a picture.

Audiologist - A Health care professional who is trained to evaluate hearing loss and related disorders. An audiologist uses a variety of tests and procedures to assess hearing and balance function and to fit and dispense hearing aids and other assistive devices for hearing.

Auditory Brainstem Response Test (ABR) - is an auditory evoked potential that originates from the auditory nerve. It is often used with babies/young children. Electrodes are placed on the head (similar to electrodes placed around the heart when an electrocardiogram is run), and brain wave activity in response to sound is recorded.

Aural - relating to the ear.

Auricular - relating to the ear.

BAHA - Bone anchored hearing aid. This is typically used for patients with atresia. This device combines a sound processor with a small titanium fixture implanted behind the ear. The system allows sound to be conducted through the bone rather than via the middle ear - a process known as direct bone conduction. Surgery is minor, and many patients report a wide range of advantages over other hearing devices. Baha is used to aid people with chronic ear infections, congenital hearing loss and single sided deafness.

Behind-the-ear hearing aid - These are the most popular style of hearing aids for children because they provide the greatest amount of flexibility in fitting. This type of hearing aid sits on top of the child's ear. Amplified sound is routed to the ear through tubing and an ear-piece called an 'ear-mould'. These hearing aids can provide the amplification necessary for even a profound hearing loss, can be attached to other special listening devices such as FM systems, and can have excellent flexibility in how they are programmed. Behind-the-ear hearing aids and ear-moulds now come in a variety of bright colours and designs.

In-the-ear hearing aid - This type of hearing aid fits completely in the ear and outer ear canal. This is a very popular style for adult hearing aid users but there are drawbacks for children using them. They cannot be used with FM systems and usually cannot be used with other listening devices. Also, young children's ears are continually growing which results in the need for frequent re-casing and re-shelling of the hearing aids. While this is being done, the child is usually left without amplification for a few days. This size of hearing aid is not powerful enough to provide adequate amplification for severe or profound hearing loss. For severe or profound hearing loss, a behind-the-ear hearing aid is required.

Bilateral - on two sides.

Canalplasty - surgical alteration of the bony ear canal.

Cholosteatoma - a benign skin sack formation/growth in the ear. Left untreated they can cause a lot of problems due to enlargement and erosion and damage of normal structures.

Cochlea - the snail shaped structure in the inner ear. This is the part of the inner ear that enables you to hear. It contains the hearing nerve receptor cells. These receptor cells are called "hair cells" named for the small projections on their surface that receive sound vibrations.

Cochlear implant - a device surgically implanted into the cochlea to bypass the sensory organ to activate the hearing nerve directly. It is designed for individuals with severe-profound sensorineural hearing loss who do not get any adequate benefit from hearing aid amplification. A unit consists of a directional microphone, cable and transmitter which fit behind the ear. To be considered a candidate for a cochlear implant a child must be over 18 12 months of age and have a severe-profound sensorineural hearing loss in both ears.

Conductive Hearing Loss - a reduction in sound level resulting from a blockage or abnormality of the outer ear or middle ear. It is a hearing loss because the sound cannot get through.

Congenital - Present from birth.

Cosmetic Surgery - this is surgery performed to reshape normal structures of the body.

CROS (Contra lateral Routing of Signal) - a hearing aid system designed for people with unilateral hearing loss (or for hearing losses which are much more severe in one ear than the other). A microphone is placed on the poorer ear and the signal is routed to a hearing aid on the better ear.

Deaf - is the term used to describe a hearing loss greater than 90dB.

Decibel (dB) - a unit for measuring the loudness of sound. Soft sounds are usually at 0-35 dB, moderate sounds at 35dB to 70dB and loud sounds at 70dB to 110dB. The higher the number the louder the sound.

ENT - Ears, Nose & Throat

FM System - a classroom tool for deaf or hard of hearing children. The teacher wears a microphone and this sound is then transmitted into the hearing aid.

Frequency - the unit of measurement related to the pitch of sound. For example high frequency sounds are sounds that have a high pitch such as an alarm and low frequency sounds are sounds that have a very low pitch.

Hard of Hearing - the term used to describe those who have mild to severe hearing loss.

Localization - the ability to determine where a sound is coming from. Middle Ear - the part of the ear that includes the ear drum and the three tiny bones of the middle ear.

Mild Hearing Loss - a person who hears sounds at between 20 to 40db.

Mixed Hearing Loss - a combination of both conductive and sensorineural hearing loss.

Moderate Hearing Loss - a person who hears sounds at between 40 to 60db.

Normal Hearing - a person who hears sounds, across a range of frequencies, at 0 to 20 db is considered to have normal hearing.

Ossicles - the three tiny bones in the middle ear, (malleus, incus and stapes).

Otolaryngologist- Physician/surgeon who specializes in diseases of the ears, nose, throat, and head and neck.

Otologist - a surgeon who specialises in treatment of ear problems.

Outer Ear - the external portion of the ear consisting of the pinna and ear canal.

Pinna - the external ear shape that sits on the side of your head. Profound Hearing Loss - a person who hears sounds at 80db or more.

Reconstructive Surgery - this is surgery performed on abnormal structures of the body caused by birth defects, trauma, injury or disease.

Sensorineural Hearing Loss - a loss caused by damage to the inner ear (cochlear hair cells) and/or the hearing nerve. In some situations, making sound louder (such as with a hearing aid) corrects the problem. In others, even with adequately loud sound, distortion of the sound due to the nerve damage can make it less useful Not only is sound not loud enough to detect, when it is made loud enough there is significant distortion which will effect a child's ability to understand speech. Sensorineural hearing losses cannot be corrected medically or surgically.

Severe Hearing Loss - a person who hears sounds at between 60 to 80db.

Sound Field System - a classroom tool for hard of hearing children which allows students to hear equally well wherever they are seated in the room. The teacher wears a microphone and the sound is transmitted to speakers around the classroom or directly to a device the child wears (either a "walkman type" headset or directly to a hearing aid). It is an amplification system which provides the spread of sound around the room.

Speech Frequencies - the speech frequencies within 500-4000Hz, the region most important for hearing and understanding of speech.

Stenosis - Narrowing of the ear canal.

Unilateral - on one side only.