Tag: Hearing impairment

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Ailmemts & Remedies

Deafness and Hearing Problems

Definition:
Deafness is a condition wherein the ability to detect certain frequencies of sound is completely or partially impaired. When applied to humans, the term hearing impaired is rejected by the Deaf Culture movement, where the terms deaf and hard-of-hearing are preferred.

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Hearing sensitivity is indicated by the quietest sound that an animal can detect, called the hearing threshold. In the case of humans and some animals, this threshold can be accurately measured by a behavioral audiogram. A record is made of the quietest sound that consistently prompts a response from the listener. The test is carried out for sounds of different frequencies. There are also electro-physiological tests that can be performed without requiring a behavioral response.

Normal hearing thresholds within any given species are not the same for all frequencies. If different frequencies of sound are played at the same amplitude, some will be perceived as loud, and others quiet or even completely inaudible. Generally, if the gain or amplitude is increased, a sound is more likely to be perceived. Ordinarily, when animals use sound to communicate, hearing in that type of animal is most sensitive for the frequencies produced by calls, or in the case of humans, speech. All levels of the auditory system contribute to this sensitivity toward certain frequencies, from the outer ear’s physical characteristics to the nerves and tracts that convey the nerve impulses of the auditory portion of the brain.

A hearing loss exists when an animal has diminished sensitivity to the sounds normally heard by its species. In humans, the term hearing impairment is usually reserved for people who have relative insensitivity to sound in the speech frequencies. The severity of a hearing loss is categorized according to the increase in volume that must be made above the usual level before the listener can detect it. In profound deafness, even the loudest sounds that can be produced by an audiometer (an instrument used to measure hearing) may not be detected.

Another aspect to hearing involves the perceived clarity of a sound rather than its amplitude. In humans, that aspect is usually measured by tests of speech perception. These tests measure one’s ability to understand speech, not to merely detect sound. There are very rare types of hearing impairments which affect speech understanding alone.

Causes:
The following are some of the major causes of hearing loss:-

*Age:-
Presbycusis, the progressive loss of ability to hear high frequencies with increasing age, begins in early adulthood, but does not usually interfere with ability to understand conversation until much later. Although genetically variable it is a normal concomitant of aging and is distinct from hearing losses caused by noise exposure, toxins or disease agents.

*Long-term exposure to environmental noise:-
Populations of people living near airports or freeways are exposed to levels of noise typically in the 65 to 75 dB(A) range. If lifestyles include significant outdoor or open window conditions, these exposures over time can degrade hearing. The U.S. EPA and various states have set noise standards to protect people from these adverse health risks. The EPA has identified the level of 70 dB(A) for 24 hour exposure as the level necessary to protect the public from hearing loss and other disruptive effects from noise, such as sleep disturbance, stress-related problems, learning detriment, etc. (EPA, 1974).

Noise-induced hearing loss (NIHL) typically is centered at 3000, 4000, or 6000 Hz. As noise damage progresses, damage starts affecting lower and higher frequencies. On an audiogram, the resulting configuration has a distinctive notch, sometimes referred to as a “noise notch.” As aging and other effects contribute to higher frequency loss (6–8 kHz on an audiogram), this notch may be obscured and entirely disappear.

Louder sounds cause damage in a shorter period of time. Estimation of a “safe” duration of exposure is possible using an exchange rate of 3 dB. As 3 dB represents a doubling of intensity of sound, duration of exposure must be cut in half to maintain the same energy dose. For example, the “safe” daily exposure amount at 85 dB A, known as an exposure action value, is 8 hours, while the “safe” exposure at 91 dB(A) is only 2 hours (National Institute for Occupational Safety and Health, 1998). Note that for some people, sound may be damaging at even lower levels than 85 dB A. Exposures to other ototoxins (such as pesticides, some medications including chemotherapy, solvents, etc.) can lead to greater susceptibility to noise damage, as well as causing their own damage. This is called a synergistic interaction.

Some American health and safety agencies (such as OSHA-Occupational Safety and Health Administration and MSHA-Mine Safety and Health Administration), use an exchange rate of 5 dB. While this exchange rate is simpler to use, it drastically underestimates the damage caused by very loud noise. For example, at 115 dB, a 3 dB exchange rate would limit exposure to about half a minute; the 5 dB exchange rate allows 15 minutes.

While OSHA, MSHA, and FRA provide guidelines to limit noise exposure on the job, there is essentially no regulation or enforcement of sound output for recreational sources and environments, such as sports arenas, musical venues, bars, etc. This lack of regulation resulted from the defunding of ONAC, the EPA’s Office of Noise Abatement and Control, in the early 1980s. ONAC was established in 1972 by the Noise Control Act and charged with working to assess and reduce environmental noise. Although the Office still exists, it has not been assigned new funding.

Many people are unaware of the presence of environmental sound at damaging levels, or of the level at which sound becomes harmful. Common sources of damaging noise levels include car stereos, children’s toys, transportation, crowds, lawn and maintenance equipment, power tools, gun use, and even hair dryers. Noise damage is cumulative; all sources of damage must be considered to assess risk. If one is exposed to loud sound (including music) at high levels or for extended durations (85 dB A or greater), then hearing impairment will occur. Sound levels increase with proximity; as the source is brought closer to the ear, the sound level increases.

*Genetic:-
Hearing loss can be inherited. Both dominant genes and recessive genes exist which can cause mild to profound impairment. If a family has a dominant gene for deafness it will persist across generations because it will manifest itself in the offspring even if it is inherited from only one parent. If a family had genetic hearing impairment caused by a recessive gene it will not always be apparent as it will have to be passed onto offspring from both parents. Dominant and recessive hearing impairment can be syndromic or nonsyndromic. Recent gene mapping has identified dozens of nonsyndromic dominant (DFNA#) and recessive (DFNB#) forms of deafness.

#The first gene mapped for non-syndromic deafness, DFNA1, involves a splice site mutation in the formin related homolog diaphanous 1 (DIAPH1). A single base change in a large Costa Rican family was identified as causative in a rare form of low frequency onset progressive hearing loss with autosomal dominant inheritance exhibiting variable age of onset and complete penetrance by age 30.

#The most common type of congenital hearing impairment in developed countries is DFNB1, also known as Connexin 26 deafness or GJB2-related deafness.

#The most common dominant syndromic forms of hearing impairment include Stickler syndrome and Waardenburg syndrome.

#The most common recessive syndromic forms of hearing impairment are Pendred syndrome, Large vestibular aqueduct syndrome and Usher syndrome.

#The congenital defect microtia can cause full or partial deafness depending upon the severity of the deformity and whether or not certain parts of the inner or middle ear are affected.

#Mutations in PTPRQ Are a Cause of Autosomal-Recessive Nonsyndromic Hearing Impairment

*Disease or illness:-
#Measles may result in auditory nerve damage

#Meningitis may damage the auditory nerve or the cochlea

#Autoimmune disease has only recently been recognized as a potential cause for cochlear damage.
#Although probably rare, it is possible for autoimmune processes to target the cochlea specifically, without symptoms affecting other organs. Wegener’s granulomatosis is one of the autoimmune conditions that may precipitate hearing loss.

#Mumps (Epidemic parotitis) may result in profound sensorineural hearing loss (90 dB or more), unilateral (one ear) or bilateral (both ears).

#Presbycusis is a progressive hearing impairment accompanying age, typically affecting sensitivity to higher frequencies (above about 2 kHz).

#Adenoids that do not disappear by adolescence may continue to grow and may obstruct the Eustachian tube, causing conductive hearing impairment and nasal infections that can spread to the middle ear.

#AIDS and ARC patients frequently experience auditory system anomalies.

#HIV (and subsequent opportunistic infections) may directly affect the cochlea and central auditory system.

#Chlamydia may cause hearing loss in newborns to whom the disease has been passed at birth.

#Fetal alcohol syndrome is reported to cause hearing loss in up to 64% of infants born to alcoholic mothers, from the ototoxic effect on the developing fetus plus malnutrition during pregnancy from the excess alcohol intake.

#Premature birth results in sensorineural hearing loss approximately 5% of the time.

#Syphilis is commonly transmitted from pregnant women to their fetuses, and about a third of the infected children will eventually become deaf.

#Otosclerosis is a hardening of the stapes (or stirrup) in the middle ear and causes conductive hearing loss.

#Superior canal dehiscence, a gap in the bone cover above the inner ear, can lead to low-frequency conductive hearing loss, autophony and vertigo.

*Medications:–
Some medications cause irreversible damage to the ear, and are limited in their use for this reason. The most important group is the aminoglycosides (main member gentamicin) and platinum based chemotherapeutics such as cisplatin.

Various other medications may reversibly affect hearing. This includes some diuretics, aspirin and NSAIDs, and macrolide antibiotics.

The 1995 Miss America Heather Whitestone lost her hearing after receiving strong antibiotics for haemophilus influenzae.[citation needed] Extremely heavy hydrocodone (Vicodin or Lorcet) abuse is known to cause hearing impairment. Commentators have speculated that radio talk show host Rush Limbaugh’s hearing loss was at least in part caused by his admitted addiction to narcotic pain killers, in particular Vicodin and OxyContin.

*Exposure to ototoxic chemicals:-
In addition to medications, hearing loss can also result from specific drugs; metals, such as lead; solvents, such as toluene (found in crude oil, gasoline[6] and automobile exhaust, for example); and asphyxiants. Combined with noise, these ototoxic chemicals have an additive effect on a person’s hearing loss.Hearing loss due to chemicals starts in the high frequency range and is irreversible. It damages the cochlea with lesions and degrades central portions of the auditory system. For some ototoxic chemical exposures, particularly styrene, the risk of hearing loss can be higher than being exposed to noise alone. Controlling noise and using hearing protectors are insufficient for preventing hearing loss from these chemicals. However, taking antioxidants helps prevent ototoxic hearing loss, at least to a degree. The following list provides an accurate catalogue of ototoxic chemicals:-

#Drugs
antimalarial, antibiotics, anti-inflammatory (non-steroidal), antineoplastic, diuretics

#Solvents
toluene, styrene, xylene, n-hexane, ethyl benzene, white spirits/Stoddard, carbon disulfide, fuels, perchloroethylene, trichloroethylene, p-xylene

#Asphyxiants
carbon monoxide, hydrogen cyanide

#Metals
lead, mercury, organotins (trimethyltin)

#Pesticides/Herbicides
paraquat, organophosphates

#Physical trauma
There can be damage either to the ear itself or to the brain centers that process the aural information conveyed by the ears.

#People who sustain head injury are especially vulnerable to hearing loss or tinnitus, either temporary or permanent.

#Exposure to very loud noise (90 dB or more, such as jet engines at close range) can cause progressive hearing loss. Exposure to a single event of extremely loud noise (such as explosions) can also cause temporary or permanent hearing loss. A typical source of acoustic trauma is an excessively loud music concert. I King Jordan lost his hearing after suffering a skull fracture as a result of a motorcycle accident at age 21

Diagnosis:
The diagnosis starts with verifying the medical and the family histories of the person. Ear examination is done to assess the hearing and the balancing ability of the person.

 The following tests may be required to confirm the diagnosis and to find the cause:

Audiogram: The person sits in a sound proof room and wears a headphone attached to a machine. Different sounds of varying intensity or loudness are sent through the headphone and the person is asked to tell whether he hears the sound or not. Each ear is tested separately. An audiogram helps to assess any hearing loss.

Electrocochleography: This test measures electrical activity in the cochlea and in the nerves that take sensations from the ear to the brain. This is done by passing a thin needle into the ear that records the activity and sends it to an attached computer. In people who have SHL, the activity will be abnormal because of damage.

Caloric Testing: It is done to assess the functioning of the vestibular part of the inner ear, which maintains the body balance. The person is asked to sit in a chair. Cold and hot water is poured into the ear alternately and the associated involuntary eye movements are checked.

Computed Tomography Scan or Magnetic Resonance Imaging: Multiple images of the affected ear are taken and then they are assembled by a computer to generate a clear image of the internal body parts. These tests help to assess any damage in the inner ear. Also, any nerve tumor, such as Acoustic Neuroma, can be diagnosed.

Blood Tests such as fluorescent treponemal antibody absorption may be required to check for Syphili. Antinuclear antibodies may be checked to detect any autoimmune disorders.

Treatment:
The treatment of hearing loss depends on its cause. For example:

•ear wax can be removed,
•ear infection can be treated with medications,
•medications that are toxic to the ear can be avoided and;
•occasionally surgical procedures are necessary.

Gene therapy:-
A 2005 study achieved successful regrowth of cochlea cells in guinea pigs.[13] It is important to note, however, that the regrowth of cochlear hair cells does not imply the restoration of hearing sensitivity as the sensory cells may or may not make connections with neurons that carry the signals from hair cells to the brain. A 2008 study has shown that gene therapy targeting Atoh1 can cause hair cell growth and attract neuronal processes in embryonic mice. It is hoped that a similar treatment will one day ameliorate hearing loss in humans.

Assistive techniques and devices for hearing impairment:-
Many hearing impaired individuals use assistive devices in their daily lives:

#Individuals can communicate by telephone using Telecommunications Device for the Deaf (TDD). These devices look like typewriters or word processors and transmit typed text over regular telephone lines.Other names in common use are textphone and minicom.

#There are several new Telecommunications Relay Service technologies including IP Relay and captioned telephone technologies.

#Mobile textphone devices came onto the market as of 2004, allowing simultaneous two way text communication.

#Videophones and similar video technologies can be used for distance communication using sign language. Video conferencing technologies permit signed conversations as well as permitting a sign language-English interpreter to voice and sign conversations between a hearing impaired person and that person’s hearing party, negating the use of a TTY device or computer keyboard.

#Video Relay Service and Video Remote Interpreting services also use a third-party telecommunication service to allow a deaf or hard-of-hearing person to communicate quickly and conveniently with a hearing person, through a sign language interpreter.

#In the U.S., the UK, the Netherlands and many other western countries there are Telecommunications Relay Services so that a hearing impaired person can communicate over the phone with a hearing person via a human translator. Wireless, internet and mobile phone/SMS text messaging are beginning to take over the role of the TDD.

#Phone captioning is a service in which a hearing person’s speech is captioned by a third party, enabling a hearing impaired person to conduct a conversation with a hearing person over the phone.

#Hearing dogs are a specific type of assistance dog specifically selected and trained to assist the deaf and hearing impaired by alerting their handler to important sounds, such as doorbells, smoke alarms, ringing telephones, or alarm clocks.

#Other assistive devices include those that use flashing lights to signal events such as a ringing telephone, a doorbell, or a fire alarm.

#The advent of the Internet’s World Wide Web and closed captioning has given the hearing impaired unprecedented access to information. Electronic mail and online chat have reduced the need for deaf and hard-of-hearing people to use a third-party Telecommunications Relay Service in order to communicate with the hearing and other hearing impaired people;

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.

Resources:
http://www.bbc.co.uk/health/physical_health/conditions/deafness1.shtml
http://en.wikipedia.org/wiki/Hearing_impairment
http://www.medicinenet.com/deafness/article.htm

http://www.assiutknol.com/hearing-loss-and-deafness

http://healthscribes.com/disease/Hearing+Loss,+Sudden

http://engagingtech.org/csdmovies/wp-content/uploads/2010/10/international_symbol_for_deafness.jpg

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Ailmemts & Remedies Pediatric

Cytomegalovirus

Definition
Cytomegalovirus (say: si-toe-meg-ah-low-vi-russ), or CMV, is a very common virus. It  is a viral genus of the viral group known as Herpesviridae or herpesviruses. It is typically abbreviated as CMV: The species that infects humans it is commonly known as human CMV (HCMV) or human herpesvirus-5 (HHV-5), and is the best studied of all cytomegoloviruses. Within Herpesviridae, CMV belongs to the Betaherpesvirinae subfamily, which also includes the genera Muromegalovirus and Roseolovirus. It is related to other herpesviruses within the subfamilies of Alphaherpesvirinae that includes herpes simplex viruses (HSV)-1 and -2 and varicella-zoster virus (VZV), and the Gammaherpesvirinae subfamily that includes Epstein-Barr virus. All herpesviruses share a characteristic ability to remain latent within the body over long periods. Although they may be found throughout the body, CMV infections are frequently associated with the salivary glands in humans and other mammals. Other CMV viruses are found in several mammal species, but species isolated from animals differ from HCMV in terms of genomic structure, and have not been reported to cause human disease.

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People are usually infected by the time they are 2 years old or during their teenage years and carry the virus for life (usually in a dormant or inactive state). The majority of adults carry the virus by the time they are 40 years of age.

Many people are infected with CMV and don’t even know it because the virus rarely causes symptoms and usually does not cause long-term problems.

However, CMV can cause problems in people who have weak immune systems and in a newborn if the mother gets the infection during pregnancy.

Causes:
CMV gets into body fluids, such as saliva, blood, urine, semen and breast milk. A person is able to transmit (or “shed”) the virus to others only when it is active in his or her system (not dormant). It can be spread from one person to another through sexual contact and contact with blood and other body fluids. CMV can rarely be transmitted by blood transfusion or organ transplantation. In developed countries, blood supplies are screened for CMV when they’re to be used for those at greatest risk from the infection.

 Symptoms:

Usually, CMV does not cause symptoms or only causes mild symptoms. A few people will have symptoms that are similar to mononucleosis. Symptoms of CMV can include:

•Sore throat
•Swollen lymph nodes (lymph glands)
•Fever
•Headache
•Fatigue
•Weakness
•Muscle aches
•Loss of appetite


People who have weakened immune systems due to conditions like human immunodeficiency virus (HIV) or because they received an organ transplant and are taking immunosuppressant medicines may have severe symptoms. (Immunosuppressant medicines are medicines that lower or suppress the immune system.) Symptoms of severe CMV include:
•Blindness
•Pneumonia
•Diarrhea
•Bleeding ulcers in the esophagus (windpipe) or intestines
•Inflammation of the brain (encephalitis)
•Seizures

If a pregnant woman transmits CMV to her unborn baby, miscarriage, stillbirth or death of the newborn may occur. Newborns who survive are at an increased risk for hearing loss and mental retardation. However, only 1% of newborns who are infected with CMV during pregnancy experience problems from the virus. Most are born healthy, or with only mild CMV symptoms.

Who’s affected?
In most cases, CMV is harmless, but for some people infection can have disastrous consequences.

People with weakened immune systems (because of HIV, for example) can suffer serious illness. They may experience high fever for two or three weeks, accompanied by hepatitis and jaundice.

Other serious complications include pneumonia, inflammation of the brain (encephalitis) and blindness as a result of inflammation of the retina at the back of the eye.

CMV remains in the body for life. For those with strong immune systems, it remains inactive. If the immune system is weakened through illness or medical treatments, CMV may be reactivated, causing further medical problems and distress.

If a pregnant woman becomes infected with CMV for the first time, the virus may pass through the placenta and infect her unborn baby. If this happens early in pregnancy, the risk of miscarriage increases, as does the chance of the baby being born with malformations. For example, CMV infection in the womb is the leading cause of congenital deafness.

If the infection is contracted later in pregnancy, stillbirth and premature labour are more likely. A newborn baby may suffer severe illness shortly after birth – jaundice, enlargement of the liver and blood disorders.

Diagnosis:
CMV is diagnosed with a blood test.

CMV is more likey to cause vision problems in people who have weakened immune systems, so if you have conditions such as HIV or AIDS, your doctor may recommend that you visit an eye doctor to find out whether the virus has infected your eyes. Be sure to let your doctor know if you are having any painless blurring of your vision, “floaters” only in one eye, light flashes or areas of blindness. You should also let your doctor(s) know if you are experiencing frequent shortness of breath with flu-like symptoms, or if you are having problems hearing.

Treatment:
For otherwise healthy people, CMV usually doesn’t require treatment. If your immune system is weakened, your doctor may use one of several different medicines to treat CMV infection. However, because CMV is a virus, regular antibiotics won’t work against it. Antiviral drugs are usually prescribed, which slows the virus down (but cannot cure CMV).

If you are pregnant, your doctor may want to test you for CMV to determine if there is a risk for your unborn baby. If you do carry the virus, your doctor may suggest a test called amniocentesis, which collects a sample of the amniotic fluid for testing. It can help determine whether your unborn baby has CMV.

If you are pregnant and your baby has CMV, you doctor will likely check your baby once he or she is born for any problems or birth defects so they can be treated early. Treatable symptoms in newborns include pneumonia, hearing loss and inflammation of the eye.

Prevention:
In child care centers, as many as 70% of children ages 1 to 3 can shed the virus. Careful, frequent hand washing with soap and water may help prevent the spread of CMV.

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.

Resources:
http://www.bbc.co.uk/health/physical_health/conditions/cmv1.shtml
http://familydoctor.org/online/famdocen/home/common/infections/common/viral/743.html
http://en.wikipedia.org/wiki/Cytomegalovirus
http://medippt.files.wordpress.com/2010/10/cytomegalovirus.jpg

http://health.allrefer.com/health/cmv-immunocompromised-host-cmv-cytomegalovirus.html

http://archive.microbelibrary.org/ASMOnly/Details.asp?ID=658

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Ailmemts & Remedies

Acoustic neuroma

Other Names : Acoustic neurilemmoma, Acoustic neurinoma, Auditory tumor, Vestibular schwannoma


Definition:
Acoustic neuroma is a non-cancerous tumor that develops on the nerve that connects the ear to the brain.  The neuroma actually arises from cells called Schwann cells that cover the nerve, rather than from the nerve itself, and is therefore correctly called a vestibular schwannoma.

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The tumor usually grows slowly. As it grows, it presses against the hearing and balance nerves. At first, you may have no symptoms or mild symptoms. They can include

*Loss of hearing on one side
*Ringing in ears
*Dizziness and balance problems

Acoustic neuroma can be difficult to diagnose, because the symptoms are similar to those of middle ear problems. Ear exams, hearing tests and scans can show if you have it.

If the tumor stays small, you may only need to have it checked regularly. If you do need treatment, surgery and radiation are options. If the tumors affect both hearing nerves, it is often because of a genetic disorder called neurofibromatosis. The tumor can also eventually cause numbness or paralysis of the face. If it grows large enough, it can press against the brain, becoming life-threatening.


Symptoms:
Invariably the acoustic neuroma develops only on one side of the head, causing symptoms to occur in that ear. These may include:

*Ringing (tinnitus) in the affected ear
*Vertigo
*Headaches, facial numbness, deterioration of sight and loss of co-ordination are late symptoms
*Hearing loss, usually gradual — although in some cases sudden — and occurring on only one side or more pronounced on one side
*Unsteadiness, loss of balance
*Dizziness (vertigo)
*Facial numbness and weakness

In rare cases, an acoustic neuroma may grow large enough to compress the brainstem and be life-threatening.

Causes:
The cause of acoustic neuromas — tumors on the main nerve leading from your inner ear to your brain (vestibulocochlear nerve) — appears to be a malfunctioning gene on chromosome 22. Normally, this gene produces a protein that helps control the growth of Schwann cells covering the nerves. What makes this gene malfunction isn’t clear. Scientists do know the faulty gene is inherited in about half the cases of neurofibromatosis 2, a rare disorder that typically involves the growth of tumors on the vestibulocochlear nerve on each side of the head (bilateral neuromas).

Most people are between the ages of 40 and 60 when an acoustic neuroma is discovered but why they develop one in the first place is unclear.

Acoustic neuromas may occur sporadically (meaning the cause is unknown), or in some cases occur as part of von Recklinhausen neurofibromatosis, in which case the neuroma may take on one of two forms.

In Neurofibromatosis type I, a schwannoma may sporadically involve the 8th nerve, usually in adult life, but may involve any other cranial nerve or the spinal root. Bilateral acoustic neuromas are rare in this type.
In Neurofibromatosis type II, bilateral acoustic neuromas are the hallmark and typically present before the age of 21. These tumors tend to involve the entire extent of the nerve and show a strong autosomal dominant inheritance. Incidence is about 5 to 10%.

The usual tumor in the adult presents as a solitary tumor, originating in the nerve. It usually arises from the vestibular portion of the 8th nerve, just within the internal auditory canal. As the tumor grows, it usually extends into the posterior fossa to occupy the angle between the cerebellum and the pons (cerebellopontine angle). Because of its position, it may also compress the 5th, 7th, and less often, the 9th and 10th cranial nerves. Later, it may compress the pons and lateral medulla, causing obstruction of the cerebrospinal fluid and increased intracranial pressure.

Schwannomas can occur in relation to other cranial nerves or spinal nerve roots, resulting in radiculopathy or spinal cord compression. Trigeminal neuromas are the second most common form of schwannomas involving cranial nerves. Schwannomas of other cranial nerves are very rare.

Diagnosis:
Signs and symptoms of acoustic neuroma are likely to develop gradually and because hearing loss, tinnitus and problems with balance can be indicators of other middle and inner ear problems, it may be difficult for your doctor to detect the tumor in its early stages. Acoustic neuromas often are found during screening for other conditions.

After asking questions about your symptoms, your doctor will conduct an ear exam and may request the following tests:

*Hearing test (audiometry). During this test conducted by a hearing specialist (audiologist), you wear earphones and hear sounds directed to one ear at a time. The audiologist presents a range of sounds of various tones and asks you to indicate each time you hear the sound. Each tone is repeated at faint levels to find out when you can barely hear. The audiologist will also present various words to determine your hearing ability.

*Brainstem auditory evoked response (BAER). This test checks hearing and neurological functions. Electrodes on your scalp and earlobes capture your brain’s responses to clicking noises you hear through earphones and record the responses on a graph.

*Electronystagmography (ENG). This test evaluates balance (vestibular) function by detecting abnormal rhythmic eye movement (nystagmus) often present with inner ear conditions. The test measures your involuntary eye movements while stressing your balance in various ways.

*Scans. Magnetic resonance imaging (MRI) or computerized tomography (CT) scans of your head can provide images that confirm the presence of an acoustic neuroma.

Treatment :
Acoustic neuroma is a non-cancerous growth, which means it won’t spread to and damage other parts of the body. But it can continue to grow where it is, inside the skull.

It’s important to have it removed because although it grows slowly it can press on the nerves and part of the brain, causing permanent damage. This may result in hearing loss, poor balance and coordination, weakness in the muscles of the face and pain.

When a neuroma is suspected, diagnosis can be confirmed using a CT (computerised tomography) or MRI (magnetic resonance imaging) scan. These can also show the size and position of the tumour.

Most acoustic neuromas are surgically removed, after which many of the symptoms should disappear. This is more likely to be the case when the neuroma is small. Larger neuromas may have done irreversible damage to the brain and nerves before or during surgery.

Many patients have already lost a significant amount of hearing prior to surgery and this is not something that can be reversed although 40 per cent of patients who had tinnitus (ringing in the ears) noticed an improvement in that symptom after surgery.

This is why it’s best to treat an acoustic neuroma sooner rather than later. However, because they’re slow growing, only 1-2mm a year, very small neuromas may initially be just carefully monitored.

Stereotactic Radiotherapy (‘gamma knife’) may also be used to treat an acoustic neuroma.

Risk Factors:
The only known risk factor for acoustic neuroma is having a parent with the rare genetic disorder neurofibromatosis 2, but this accounts for only a minority of cases. A hallmark characteristic of neurofibromatosis 2 is the development of benign tumors on the acoustic nerves on both sides of your head, as well as on other nerves.

Neurofibromatosis 2 is known as an autosomal dominant disorder, meaning the mutation occurs on a nonsex chromosome (autosome) and can be passed on by just one parent (dominant gene). Each child of an affected parent has a 50-50 chance of inheriting it.

Other possible but unconfirmed risk factors for acoustic neuroma include:

*Exposure to loud noise
*Childhood exposure to low-dose radiation of the head and neck
*History of parathyroid adenoma, a benign tumor of the parathyroid glands in the neck
*Heavy use of cellular telephones

Copying & Support:

Dealing with the possibility of hearing loss and facial paralysis and deciding which treatment would be best for you can be quite stressful. Here are some suggestions you may find helpful:

*Educate yourself about acoustic neuroma. The more you know, the better prepared you’ll be to make good choices about treatment. Besides talking to your doctor and your audiologist, you may want to talk to a counselor or medical social worker. Or you may find it helpful to talk to other people who’ve had an acoustic neuroma and learn more about their experiences during treatment and beyond.
*Maintain a strong support system. Family and friends can help you tremendously as you go through this difficult time. Sometimes, though, you may find the concern and understanding of other people with acoustic neuroma especially comforting. Your doctor or a medical social worker may be able to put you in touch with a support group. Or you may find a real or virtual support group through the Acoustic Neuroma Association.

Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.

Resources:
http://www.bbc.co.uk/health/physical_health/conditions/acousticneuroma.shtml
http://www.nlm.nih.gov/medlineplus/acousticneuroma.html
http://en.wikipedia.org/wiki/Vestibular_schwannoma
http://www.mayoclinic.com/health/acoustic-neuroma/DS00803

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This Fat Can Actually Protect Against Hearing Loss

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Increased intakes of omega-3 fats may reduce the risk of age-related hearing loss, says a new study.

CLICK & SEE THE PICTURES

High omega-3 intake was associated with a significant reduction in the risk of age-related hearing loss (presbycusis) in people over the age of fifty.Hearing loss is the most common sensory disorder in the U.S.

NutraIngredients reports:
“Other micronutrients have been linked to reducing the risk of age-related hearing loss. In 2007 scientists from Wageningen University reported that folic acid supplements delayed age-related hearing loss in the low frequency region …

Another study … indicated a role for beta carotene and vitamins C and E, and the mineral magnesium in preventing prevent both temporary and permanent hearing loss in guinea pigs and mice.”

Source: NutraIngredients June 11, 2010

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More Electrodes Could Improve Conventional Cochlear Implants

Candidates for cochlear implants—an estimated million in the United States alone—include children and adults with profound deafness in both ears. An implant does not restore normal hearing but simulates sounds in the environment, including speech. More electrodes pick up more external sound and the flexible wire allows those sounds to be transmitted over more of the auditory nerves.

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The snail-shaped cochlea is difficult to access, particularly considering the multiple components involved in a cochlear implant, said Dr. Brian McKinnon. Those components include of an external microphone, speech processor and transmitter and an internal group of electrodes arranged on a thin wire that stimulate the auditory nerve.

“The wire in traditional implants is fragile and thin and may buckle,” he said. “We try to get it as far into the center of the cochlea, where the nerves are bundled, as possible – the idea being that the more electrodes on the nerves, the better the sound.”

Because they buckle, physicians typically can’t optimally insert the wire, and electrodes can, in some cases, injure the cochlea, he said.

The new device, called the thin film array, pairs 12 electrodes on a thinner, more flexible wire. The wire’s thinness has, so far, allowed surgeons to place more electrodes into the cochlea than they could with a conventional electrode. With more electrodes than standard models, the implant improves the quality of sound.

“This device could mean could mean a several-fold improvement of the sound’s resolution,” Dr. Kenneth Iverson said. “For the patient, it would be like the difference between hearing a Bach concerto played by a music box versus a quartet.”

McKinnon compared the improvement to adding more fingers and more notes to a piano performance.

There are other benefits too. “Because the thinner wire means less trauma to the ear, it could also mean more preservation of residual hearing for patients,” Iverson said.

Source:Elements4Health

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