Hearing

Hearing Loss Your Genes and Hearing Loss Hearing Aids

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Associates Of Otolaryngology cares about your hearing. We are building the most comprehensive website to help answer your questions and provide 24 hour hearing information. You’ll be able to visit us soon at www.harvardparkhearing.com
Until our new website is live here is some information that will hopefully answer your hearing questions.

TAKE OUR HEARING QUIZ:

SIGNS OF HEARING LOSS:

[. ] Do you feel that people mumble or speak too softly?

[. ] Do you hear better with one ear than the other?

[. ] Do friends and family tell you that they have to repeat things for you?

[. ] Do you sometimes feel that you can hear people, but have trouble understanding them?

[. ] Do you avoid certain situations because it is too difficult to hear?

[. ] Do you have trouble understanding women or children?

[. ] Do you have difficulty following conversations in the car?

[. ] Do you have trouble understanding people on the telephone?

If you answered "yes" to two or more of these questions you should have your hearing tested

Hearing Loss

I Don't Hear Well. What Should I Do? What Should I Expect?

Because some hearing problems can be medically corrected, first visit a physician who can refer you to an otolaryngologist (an ear, nose, and throat specialist ). If you have ear pain, drainage, excess earwax, hearing loss in only one ear, sudden or rapidly progressive hearing loss, or dizziness, it is especially important that you see an otolaryngologist. Then, get a hearing assessment from an audiologist (a nonphysician health care professional). A screening test from a hearing aid dealer may not be adequate. Many otolaryngologists have an audiologist associate in their office who will assess your ability to hear pure tone sounds and to understand words. The results of these tests will show the degree of hearing loss and whether it is conductive or sensorineural and may give other medical information about your ears and your health.

*Conductive Hearing Loss

A hearing loss is conductive when there is a problem with the ear canal, the eardrum and/or the three bones connected to the eardrum. Common reasons for this type of hearing loss are a plug of excess wax in the ear canal or fluid behind the eardrum. Medical treatment or surgery may be available for these and more complex forms of conductive hearing loss.

*Sensorinural Hearing Loss

A hearing loss is sensorineural when it results from damage to the inner ear (cochlea) or auditory nerve, often as a result of the aging process and/or noise exposure. Sounds may be unclear and/or too soft. Sensitivity to loud sounds may occur. Medical or surgical intervention cannot correct most sensorineural hearing losses. However, hearing aids may help you reclaim some sounds that you are missing as a result of nerve deafness.

Your Genes and Hearing Loss

One of the most common birth defects is hearing loss or deafness (congenital), which can affect as many as three of every 1,000 babies born. Inherited genetic defects play an important role in congenital hearing loss, contributing to about 60 percent of deafness occurring in infants. Although exact data is not available, it is likely that genetics plays an important role in hearing loss in the elderly. Inherited genetic defects are just one factor that can lead to hearing loss and deafness, both of which may occur at any stage of a person’s lifespan. Other factors may include: medical problems, environmental exposure, trauma, and medications.

The most common and useful distinction in hearing impairment is syndromic versus non-syndromic.

Non-syndromic hearing impairment accounts for the vast majority of inherited hearing loss, approximately 70 percent. Autosomal- recessive inheritance is responsible for about 80 percent of cases of non-syndromic hearing impairment, while autosomal-dominant genes cause 20 percent, less than two percent of cases are caused by X-linked and mitochondrial genetic malfunctions.

Syndromic means that the hearing impairment is associated with other clinical abnormalities. Among hereditary hearing impairments, 15 to 30 percent are syndromic. Over 400 syndromes are known to include hearing impairment and can be classified as: syndromes due to cyotgenetic or chromosomal anomalies, syndromes transmitted in classical monogenic or Mendelian inheritance, or syndromes due to multi-factorial influences, and finally, syndromes due to a combination of genetic and environmental factors.

Variable expression of different aspects of syndromes is common. Some aspects may be expressed in a range from mild to severe or different combinations of associated symptoms may be expressed in different individuals carrying the same mutation within a single pedigree. An example of variable expressivity is seen in families transmitting autosomal dominant Waardenburg syndrome. Within the same family, some affected members may have dystopia canthorum (an unusually wide nasal bridge due to sideways displacement of the inner angles of the eyes), white forelock, heterochromia irides (two different-colored irises or two colors in the same iris), and hearing loss, while others with the same mutation may only have dystopia canthorum.

How Do Genes Work?

Genes are a road map for the synthesis of proteins, which are the building blocks for everything in the body: hair, eyes, ears, heart, lung, etc. Every child inherits half of its genes from one parent and half from the other parent. If the inherited genes are defective, a health disorder such as hearing loss or deafness can result. Hearing disorders are inherited in one of four ways:

Autosomal Dominant Inheritance: For autosomal dominant disorders, the transmission of a rare allele of a gene by a single heterozygous parent is sufficient to generate an affected child. A heterozygous parent has two types of the same gene (in this case, one mutated and the other normal) and can produce two types of gametes (reproductive cells). One gamete will carry the mutant form of the gene of interest, and the other the normal form. Each of these gametes then has an equal chance of being used to form the offspring. Thus the chance that the offspring of a parent with an autosomal dominant gene will develop the disorder is 50 percent. Autosomal dominant traits usually affect males and females equally.

Autosomal Recessive Inheritance: An autosomal recessive trait is characterized by having parents who are heterozygous carriers for mutant forms of the gene in question but are not affected by the disorder. The problem gene that would cause the disorder is suppressed by the normal gene. These heterozygous parents (A/a) can each generate two types of gametes, one carrying the mutant copy of the gene (a) and the other having a normal copy of the gene (A). There are four possible combinations from each of the parents, A/a, A/A, a/A, and a/a. Only the offspring that inherits both mutant copies (a/a) will exhibit the trait. Overall, offspring of these two parents will face a 25 percent chance of inheriting the disorder.

X-linked Inheritance: A male offspring has an X chromosome and a Y chromosome, while a female has two copies of the X chromosome only. Each female inherits an X chromosome from her mother and her father. On the other hand, each male inherits an X chromosome from his mother and a Y chromosome from his father. In general, only one of the two X chromosomes carried by a female is active in any one cell while the other is rendered inactive. This is why when a female inherits a defective gene on one X chromosome, the normal gene on the other X chromosome can usually compensate. As males only have one copy of the X chromosome, any defective gene is more likely to manifest into a disorder.

Mitochondrial Inheritance: Mitochondrias, small powerhouses within each cell, also contain their own DNA. Interestingly, the sperm does not have any mitochondria, and consequently, only the mitochondria in the egg from the mother can be passed from one generation to the next. This leads to an interesting inheritance pattern where only affected mothers (and not affected fathers as their sperms do not have mitochondria) can pass on a disease from one generation to the next. Sensitivity to aminoglycoside antibiotics can be inherited through a defect in mitochondrial DNA and is the most common cause of deafness in China!

In the last decade, advances in molecular biology and genetics have contributed substantially to the understanding of development, function, and pathology of the inner ear. Researchers have identified several of the various genes responsible for hereditary deafness or hearing loss, most notably the GJB2 gene mutation. As one of the most common genetic causes of hearing loss, GJB2-related hearing loss is considered a recessive genetic disorder because the mutations only cause deafness in individuals who inherit two copies of the mutated gene, one from each parent. A person with one mutated copy and one normal copy is a carrier but is not deaf. Screening tests for the GJB2 gene are available for at risk individuals to help them determine their risk of having a child with hearing problems.

Hearing Aids

Because federal regulation prohibits any hearing aid sale unless the buyer has first received a medical evaluation from a physician, you will need to see your physician before you purchase a hearing aid(s). However, the regulation says that if you are more than 18 years old and are aware of the recommendation to receive a medical exam, you may sign a waiver to forego the exam.

An otolaryngologist, audiologist, or an independent dispenser can dispense aids. Hearing aids should be custom fitted to your ear and hearing needs. Hearing aids purchased by mail-order typically cannot be custom fitted.

Cost Of Hearing Aids

Hearing aids vary in price according to style, electronic features, and local market conditions. Price can range from many hundreds of dollars to more than $2,500 for a programable, digitalized hearing aid. Purchase price should not be the only consideration in buying a hearing aid. Product reliability can save repair costs and the frustration of a malfunctioning hearing aid.

Styles Of Hearing Aids

There are several styles of hearing aids:

* Behind-the-ear (BTE) hearing aids are placed over the ear and connected with tubing to custom-fitted earpieces.
* In-the-ear (ITE) hearing aids fill the entire bowl of the ear and part of the ear canal.
* Smaller versions of ITEs are called half-shell and in-the-canal (ITC).
* The least visible aids are completely-in-the-canal (CIC).

Hearing aid options, which are appropriate for your particular hearing loss and listening needs, the size, and shape of your ear and ear canal, and the dexterity of your hands will all be considered in deciding what type of hearing aid is the best for you. Many hearing aids have special telecoil "T" switches to aid in use of the telephone and certain public sound systems. Discuss your need for a T-coil switch while you are considering hearing aid options.

Will I Need A Hearing Aid For Each Ear?

Usually, if you have hearing loss in both ears, using two hearing aids is best. Listening in a noisy environment is difficult with amplification in one ear only, and it is more difficult to distinguish where sounds are coming from. If, however, the quality of hearing in one ear is very different from the other, one hearing aid may be better than two.

What Other Questions Should I Ask?

* Ask about charges for the hearing evaluation, dispensing fee(s), and future servicing and repair.
* Inquire about the trial period policy and what fees are refundable if you return the hearing aid(s) during the trial period.
* Ask about the warranty coverage for your hearing aids and the consumers' protection program for hearing aid purchasers in your state.

What Will Happen At My Hearing Aid Fitting?

* The hearing aids will be fitted for your ears.
* Then, while wearing your hearing aids, you will be tested for word understanding in quiet and in noise and for improvement in hearing tones.
* Next, you will receive instruction about the care of your hearing aids, the batteries used to power them, a suggested wearing schedule, general expectations, and helpful communication strategies.
* You will also practice properly inserting and removing the hearing aids and batteries.

How Should I Begin Wearing The Aids?

* Start using your hearing aids in quiet surroundings, gradually building up to noisier environments.
* Note where and when that you find the hearing aids beneficial.
* Be patient and allow yourself to get used to the aids and the "new" sounds they allow you to hear.
* Keep a diary to help you remember your experiences.
* Report any concerns on a follow-up appointment.

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