Posts Tagged ‘inner ear’

Otoprotectants for Noise Induced Hearing Loss

June 29th, 2011

Hearing Professional Center
By: Allison McKenzie , Au.D.
Doctor of Audiology
5462 Glen Lakes Drive
Dallas, TX 75231
(214) 987-4114
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www.hearing-center.com

Noise induced hearing loss (NIHL) is the second most common cause of sensorineural hearing loss (SNHL) in industrialized societies. Excessive noise exposure is the only preventable cause of SNHL (Kopke, 2007). The hair cells of the inner ear are the specific structures damaged by excessive noise exposure and, in mammals, are unable to regenerate spontaneously. This physical damage can cause permanent and irreversible hearing loss as well as degrade a person’s quality of life. Knowing how the physical structure is affected by noise can aid researchers in their search for therapeutic agents that act as otoprotectants against NIHL (Ciorba et al, 2008). Personal hearing protection devices along with environmental engineering are the most prevalent protection methods of hearing conservation programs. Even with the required participation in hearing conservation programs, by workers who are exposed to noise at or above the action level, NIHL is still quite common. The current methods of protection are limited in their ability to save every listener from a NIHL. Researchers are actively searching for a pharmacologic approach that, when combined with environmental engineering and personal hearing protection devices, will more completely protect people from NIHL (Kopke, 2007).

Antioxidants

Vitamin E

Oxidative stress has been proven to contribute to the degradation of hair cells in the cochlea. Drugs with antioxidant properties, such a vitamin E, have been tested on both animals and humans. The success with vitamin E as an otoprotectant in animals is far greater than the results seen is human subjects. The different effects of antioxidants between human and animal subjects may be due to differences in pharmacokinetic and pharmacodynamic principles. More research is needed to determine when and in what intervals antioxidant treatments are needed to be the most useful in preventing NIHL in humans (Fetoni et al, 2008).

N-acetyl-l-cysteine (NAC)

The glutathione pathway is a very important antioxidant pathway in the cochlea. NAC acts as a glutathione substrate and aids the body in glutathione synthesis. Research shows the effectiveness NAC has on NIHL when given intraperitoneally and via oral gavage. ABR recordings on chinchillas show the differences between dosing methods and different types of noise exposure. Many studies have shown the otoprotectant effectiveness of NAC in animal subjects, but this particular study chose to administer high-kurtosis noise in order to simulate a typical industrial environment. The goal was to show whether NAC would be considered an effective treatment method in human subjects with a NIHL (Bielefeld et al, 2007).

Clifford and Rogers (2009) looked at the effect of antioxidants as otoprotectants for impact noise trauma. They stated that people who are exposed to impact noise are at greater risk for NIHL. They chose to study the otoprotectant effect of NAC on chinchillas. The antioxidant effected the way the cochlea reacted to changes in oxygen and nitrogen which helped protect the inner ear from severe hair cell damage. There were limitations to this study due to the difficulty the researchers faced when trying to measure the physical changes during impulse noise stimulation. Clifford and Rogers (2009) cite the work of Kopke’s unpublished pilot study of 566 Marine recruits which reported a 25% reduction in the number of Marines suffering a NIHL after a two-week period of M16 rifle exposure. These Marines were given NAC as the antioxidant otoprotective agent. There is more research on the usefulness of antioxidants as otoprotectants currently being conducted with military personnel.

A study conducted in 2006 looked at NAC given thirty minutes prior to exposure to loud music. This is the only study that administered the NAC by effervescent tablet form. The results indicated that the results from the NAC group were no different than the results from the placebo group. The author pointed out other research that suggests dosing schedule is very important to the success of NAC in preventing permanent threshold shifts (Kramer et al, 2006).

Hearing Professional Center StaffHPC Staff: (From Left) Dr. Allison McKenzie, Jared Lacy & Dr. Deborah Price

C-Jun N-terminal Kinase (JNK) Inhibitors

JNKs are stress activated protein kinases that have been shown to be responsible in the apoptosis or death of oxidative stress-damaged cells. Knowing the signaling chain of JNKs can effectively help researchers provide otoprotectants that are efficient in preventing cochlear damage. JNK inhibitors are cell permeable peptides that target specific protein groups and block the JNK from carrying out its natural course in the cell. One research study showed that the  peptide conjugate D-JNKI-1 can be injected locally to the scala tympani of explanted cochleas to provide protection from acoustic trauma as well as aminoglycosides. JNK inhibitors as otoprotectants have shown the ability to keep a temporary threshold shift from becoming a permanent hearing loss (Zine and Van de Water, 2004).

A more recent study looked at the effect of JNK inhibitors on patients whose hearing was affected by firecrackers on New Year’s Eve. The 11 subjects were selected within 24 hours of the firecracker display and had at least a 30 dBHL loss at 4 and 6 KHz. The subjects were given topical anesthesia and then given a single intratympanic injection of either .4 or 2.0 g/ml of the JNK inhibitor AM-111. The results showed no difference between the dosage groups. The study shows improvement in the thresholds of all 11 subjects, but there was not a control group to compare these results to. There is not enough evidence to say that AM-111 should be used clinically to treat acute acoustic trauma (Suckfuell et al, 2007).

Coenzyme Q10

Coenzyme Q10, which is used to increase cellular metabolism, was used to determine otoprotective effectiveness in 30 guinea pigs. The coenzyme Q10 was given intraperitoneally 2 hours before the guinea pigs were exposed to 130 dBSPL of noise centered at 4 KHz for 3 hours. ABR was used to measure pre and post results. The guinea pigs showed no differences in ABR recordings prior to noise exposure, but 7 days after the exposure the treatment group showed less of a shift than the control group. There was a marked improvement in antioxidative activity noticed 2 days post coenzyme Q10 injection (Hirose et al, 2008).

Hepatocyte Growth Factor (HGF)

HGF is a protein responsible for cell growth and different morphogenic factors. Gelatin hydrogels that had been dipped in either HGF or saline were placed on the round window of 18 guinea pigs 1 hour after a 3 hour exposure to 120 dBSPL noise. The results were measured using ABR throughout the testing process. The ABR results showed that the guinea pigs who were given the gelatin hydrogels dipped in HGF had better ABR thresholds than the saline group. The results differed in the basal portion of the cochlea only. The apical region remained unchanged for both groups (Inaoka et al, 2009).

Tacrolimus (TCR) and Melatonin (MLT) vs. Dexamethasone (DXM)

A recent study compared TCR, MLT and DXM under the same conditions to determine which if any was the most effective otoprotectant. TCR is a calcineuron inhibitor that was administered to a group of rats the day before exposure to traumatic noise and for 14 days following the noise exposure. The TCR group of rats showed an improvement in ABR thresholds within one week post noise exposure. The rats given MLT, a pineal gland hormone and antioxidant, were reported to show a marked improvement in ABR thresholds by week three post noise exposure. The group given DXM, an anti-inflammatory and immunosuppressant, showed no difference in ABR threshold recordings from the control group (Bas et al, 2009).

Implications

Most of the research on otoprotectants that has been published is based on an animal model. There are a few human subject based articles, but the methods of otoprotectant use are varied. The study that looked at the effect of NAC on people exposed to loud music used an effervescent tablet. I question whether the outcome would have been different if the dosing method had been different. My concern is the feasibility of intratympanic injections every time a person is exposed to excessive amounts of noise. More research is needed to determine which of the treatments presented in this paper are useful clinically. Every research article mentioned the need for more research to fully understand how the system works. I would like to see more human subject research to better understand how an otoprotectant might be most effective.

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Posted in Cochlea, Dallas, Hair Cell Damage, Hearing Conservation Programs, Hearing Loss, Hearing Professional Center, Hearing protection, inner ear, Noise Exposure, Noise Hazards, Noise levels, Noise-induced, Otoprotectants, Sensorineural Hearing Loss, Texas, Uncategorized

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Dizzy? You’re Not Alone!

February 18th, 2011

By: Gary Rodriguez, Ph.D.
Audiology Director
Manatee Hearing & Speech Center
701 Manatee Ave. W., Ste. 201
Bradenton, FL 34205
(941) 749-5222
www.manateehearing.com

Prevalence

According to the National Institute of Health, nearly 90 million Americans report episodes of dizziness at some point in their lives. This figure translates into more than 8 million physician visits per year from people seeking help for their dizziness problems. As we get older, balance disorders are even more prevalent. The National Institute on Aging reports one third of people over the age of 65 falls at least once per year. Other studies indicate that balance and mobility disorders are the most frequent cause of chronic disability among the elderly and that 60% of all emergency room visits by the elderly are due to falls.

Gary Rodriguez, Ph.D. - Audiology Director at Manatee Hearing & Speech CenterImpact of Balance Problems

Disorders of balance and dizziness can have a significant impact on peoples’ lives beyond the obvious feeling of instability. Many patients report an inability to concentrate on various tasks, experience memory problems, as well as having increased tension due to fear of falling. These added problems occur because for most individuals, maintaining balance is an automatic function, requiring very little active thought process or energy. In contrast, people suffering from dizziness and imbalance allocate a great amount of energy to avoid falling. In some cases, dizziness and balance problems can result in withdrawal and isolation. Many people are hesitant to move in certain positions because it results in dizziness. Their overall activity level diminishes, which in turn causes more deterioration of their functional mobility. This creates a cycle of increased dependence on others which can lead to other psycho-social difficulties.

Diagnosis and Management

Unfortunately, the diagnosis and treatment of dizziness and balance problems is extremely challenging. People with chronic long-term dizziness see an average of five physicians for their condition. This is because dizziness can result from many different causes including interaction of medications, disturbances within the inner ear, diseases of the respiratory or cardiac systems, or tumors in the central nervous system. That’s why there needs to be a coordinated effort between your physician and medical experts specifically trained to handle the diagnosis and management of dizziness problems.

By virtue of their training and experience the otolaryngologists at The Ear, Nose & Throat Associates of Manatee are uniquely qualified to handle disorders of balance and dizziness. By obtaining a comprehensive medical history, clinical evaluation, laboratory tests and diagnostic evaluations these specialists can diagnose and treat your problems with success.

No Simple Task

We’ve all heard of the clumsy kid in high school who “can’t walk and chew gum at the same time”. However, the more we know about this process, the greater appreciation we have for the complexity of this task. Balance is an interaction of sensory centers within the inner ear or vestibular system, vision, and somatosensory input (information coming from the legs, feet and sensors within tendons and joints). All of this information is processed within the brain so that the appropriate interpretation of the world around you can take place. If there is damage or compromised function of one or more of these sensory systems, the brain misinterprets the information which results in instability. Fortunately, with recent advances in diagnostic equipment and therapy techniques, there is now help for those suffering from the debilitating effects of dizziness.

Vestibular Rehabilitation

Vestibular rehabilitation is an individualized approach of specific therapy protocols to help the patient overcome problems of dizziness and imbalance. Following a battery of diagnostic testing and examination by a physician, deficits within the various systems contributing to balance (vestibular, vision and somatosensory) are determined and a specific program is developed. This approach is a “symptom driven” program to help the individual overcome or improve in the areas of daily living where they are having problems. A thorough history, as well as, functional exam of current abilities and disabilities is completed. Vestibular rehabilitation also differs from many standard treatments of dizziness in that the use of medications to treat the symptoms is discouraged. Long-term use of medications under certain conditions, can even have the effect of making symptoms worse or delaying recovery.

Candidacy

Patients who seem to respond best to vestibular rehabilitation are those with a history of a generalized state of disequilibrium, motion provoked dizziness caused by changes in head or body position “every time I roll over to the right in bed, I get dizzy”, or have documented vestibular deficits within the inner ear system based on test results. Chronic conditions that have been present for a long period of time can also respond well to treatment.

Does Therapy Hurt?

No, however, it does require effort on your part. During vestibular rehabilitation, through a systematic and progressively more challenging series of head, body and eye movements, the brain learns to interpret new input from the ears, eyes and legs. At first, many individuals feel worse before they get better because they are being asked to do some of the things that bring on their symptoms of dizziness. However, with repetition, the central nervous system learns to interpret this new information, and symptoms of disequilibrium and dizziness improve. Therapy is done in an outpatient setting with individuals coming in once or twice a week. The program typically lasts only 6-10 weeks with “homework exercises” being done on a daily basis. As you might imagine, progress depends on the patients’ initial condition, motivation, and compliance with the program.

Does It Work?

Studies from major medical centers around the country reveal that improvement in functional balance and daily living activities can occur regardless of age. Although progress may be somewhat slower for someone in their 80’s, the actual amount of improvement that can be expected from this program is similar regardless of age. Approximately 75% of the patients enrolled in a vestibular rehabilitation program have significant improvement in their symptoms. This is good news for people suffering from dizziness and balance problems who are willing to invest time and energy into trying to get better.

This therapy is not for everyone. There are literally dozens of reasons why people may feel dizzy, many of which would not be appropriate for vestibular rehabilitation therapy. However, by working closely with your doctor and with referrals to specialists trained in the management of dizziness and balance, there is help for many individuals that was not available just a few short years ago.

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Posted in Balance, Balance Disorders, Balance Problems, Bradenton, Chronic Disability, Chronic Dizziness, Diagnostic Equipment, Diagnostic Evaluations, Diagnostic Testing, Disequilibrium, Dizziness, Dizzy, Fear of Falling, Florida, Gary Rodriguez, Imbalance, inner ear, Instability, Loss of Balance, Manatee Hearing & Speech Center, Mobility Disorders, Otolaryngologists, Treating Dizziness, Uncategorized, vertigo, vestibular nerve, Vestibular Rehabilitation, Vestibular System

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Hearing Loss, Dizziness and Balance Disorders in the Elderly

May 28th, 2010

By Neil W. Aiello, Au.D., FAAA, CCC-A
Doctor of Audiology
Cheif Operations Officer
Columbia Basin Hearing Center
1149 N. Edison Street, Suite D
Kennewick, WA 99336
(509) 736-4005
www.columbiabasinhearing.com  

Adults are now living longer.  But with increased longevity comes a corresponding increase in the incidence of hearing loss, dizziness and balance problems.  Each of these conditions are common problems among the senior population.  Some revealing statistics from the National Institute on Aging include: 

  • Approximately one-third of Americans between the ages of 65 and 74 have hearing problems. 
  • Nearly half the people who are 75 or older have hearing loss. 
  • As many as 40% of all adults will experience dizziness severe enough to warrant reporting it to their doctor. 

In fact, according to the National Institutes of Health, over 90 million Americans will experience dizziness or vertigo in their lifetime.  Dizziness or vertigo is the #1 complaint of patients over the age of 70, and is the third most frequent complaint among all patients after headache and back pain.  Approximately 85% of all vertigo and balance problems are due to an inner-ear incident.

Neil Aiello, Au.D., Doctor of Audiology | Columbia Basin Hearing & Balance CenterHearing loss can have many causes including aging of the auditory system, overexposure to loud noises over a period of time, infections, ear wax buildup in the ear canal, heart conditions or stroke, head injuries, tumors, certain medicines and heredity.  Common symptoms of hearing loss include; if you often can hear people talking, but simply have difficulty understanding them; struggling to hear conversations clearly in background noise or in group situations; having difficulty hearing over the telephone or needing to turn the TV volume higher so that others complain.  These Sound Voids ™ are the result of some form of hearing loss, either temporary or permanent, and may result in situations where an individual’s hearing loss does not permit them to detect or understand important sound and speech cues.  Individuals often find that Sound Voids result in tiring, frustrating, and embarrassing situations.

Dizziness is a symptom with a multitude of possible causes.  Determining the underlying cause is one of the biggest challenges for physicians.  The most common causes are related to the inner ear; therefore, referral to an audiologist is highly recommended.  Other causes include central nervous system problem in the brain or brainstem, related heart conditions, medications, as well as infections of the inner-ear or vestibular nerve.  Specificity is the key to finding the source of the problem.  The more specific you can be about when the symptoms began, when they are most likely to occur and exactly what they feel like will help the audiologist or physician develop a more accurate diagnosis.  Be aware that determining the source of dizziness is very complex and difficult to localize.  In fact, many times the exact source of the dizziness is never found.  However, more serious sources of the problem are ruled out.

According to a distinguished expert in the field of dizziness and balance disorders; Doctors of Audiology have an educational and clinical advantage in the identification and diagnosis of many forms of dizziness and vertigo problems.  The high incidence of inner ear symptoms with balance and vertigo disorders, in conjunction with the increasing number of elderly patients that need our expertise is on the rise.  In fact, many insurance companies are seeing the proven benefits and under-utilization of Doctors of Audiology who specialize in dizziness, vertigo and balance disorders.

If you or your loved ones have hearing loss, Sound Voids™, dizziness, vertigo and/or balance problems, seek out your local Doctor of Audiology for the latest in modern professional hearing, dizziness and balance services.  General information on these topics can be found online at www.ColumbiaBasinHearing.com , www.audigygroup.com or www.dizzy.com

Definitions:

Audiologists (noun): are autonomous professionals who identify, assess, and manage disorders of the auditory, balance, and other neural systems. Audiologists provide audiological (hearing) rehabilitation to children and adults across the entire age span. Audiologists select, fit, and dispense amplification systems such as hearing aids and related devices. Audiologists currently hold a Master’s or Doctoral degrees in audiology from an accredited university or professional school.

Sound Void™ (noun):

  1. A moment lacking in clarity in hearing or understanding.
  2. An empty space in one’s life caused by the absence of sound clarity.

Hearing Loss (noun):

  1. Impairment of the sense of hearing.

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Posted in Audigy Group, AudigyCertified, Audiologist, Balance, Clinical Audiologist, Columbia Basin Hearing & Balance Center, Dizziness, Doctor of Audiology, Hearing Aids, Hearing Impaired, Hearing Loss, inner ear, Signs of Hearing Loss, Sound voids, Treatable Hearing Loss, Uncategorized, vertigo, vestibular nerve

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Tinnitus: What’s that ringing in my ears?!

May 21st, 2010

By Shannon M. Aiello, Au.D., CCC-A, FAAA
Doctor of Audiology
Directory of Audiology
Columbia Basin Hearing Center
1149 N. Edison Street, Suite D
Kennewick, WA 99336
(509) 736-4005
www.columbiabasinhearing.com  

What do David Letterman, Pete Townshend, Charles Darwin, Ludwig Van Beethoven, and Steve Martin have in common? Other than being notable individuals in history or entertainment, all of these people have lived with chronic tinnitus. And they are not alone. The American Tinnitus Association estimates that over 50 million Americans experience tinnitus. Of these, 12 million have tinnitus that is severe enough that they seek medical attention. Furthermore, approximately 2 million persons have tinnitus that is so debilitating they cannot function in their daily lives.

Tinnitus is defined as the perception of sound when no external sound is present. Tinnitus is often referred to as “ringing in the ears,” although some people hear hissing, roaring, whistling, chirping, or clicking. It can be intermittent or constant, with single or changing frequencies.Because there are so many causes of tinnitus, it is important to be thoroughly evaluated to determine what exactly is causing the ringing. Many times people are told that tinnitus is normal with aging or that they just have to live with it. This is an untrue statement. If there is a medical issue causing the tinnitus often times, when it is treated the tinnitus may subside. Although there are very few treatments for tinnitus available, it is important that people with tinnitus understand where it is coming from, what to do if it gets worse, and what they can do to successfully manage their tinnitus.

Hearing loss and noise exposure is the most typical cause of tinnitus. For these patients, the tinnitus is typically permanent. Because of the vast number of people that suffer tinnitus, there are many companies that are trying to capitalize on this condition by advertising various herbal supplements or devices to help stop the ringing. Sadly, many of these supplements and “treatments” are extremely overpriced and have not been shown clinically to reduce the perception of tinnitus.

There are however, different options available for tinnitus suffers to help reduced their awareness of the tinnitus. For those who have hearing loss in addition to tinnitus, if the hearing loss is corrected through the use of hearing aids the majority of people also notice a reduction, or complete cessation, of their tinnitus.

At Columbia Basin Hearing and Balance Center, we understand that tinnitus is a complex problem which is different with each patient. Because of this we take the time to understand what our patients are experiencing, do comprehensive testing to determine where the tinnitus is coming from, and speak extensively about individualized management, therapies, and options that may help relieve the tinnitus. We are actively pursuing and using new therapies and management strategies to help out patients experience relief from their tinnitus.

If you or your loved one has been told to learn to live with tinnitus, please contact one of our local Doctor of Audiology for the latest in testing and management of tinnitus. General information on tinnitus can be found at Columbia Basin Hearing and the American Tinnitus Association.

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Posted in Audiologist, Clinical Audiologist, Columbia Basin Hearing & Balance Center, Doctor of Audiology, Hearing Aids, Hearing Loss, Noise-induced, Ringing in the Ears, tinnitus, Uncategorized

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A Guide to Healthy Senior Living: Take steps to protect and keep your hearing!

April 22nd, 2010

A Guide to Healthy Senior Living: Take steps to protect and keep your hearing!

By: Amit Gosalia, Au.D.
Board Certified Doctor of Audiology
Audiology Clinic, Inc
505 NE 87th Ave #150
Vancouver, WA 98664
(360) 892-9367
www.audiologyclinic.com

Over 32 million Americans have hearing loss, and a half of them are under the age of 65. In the U.S., it is predicted that the number of Americans with hearing loss will exceed 70 million by the year 2030. Most of these people will suffer from noise induced hearing loss (NIHL). In 1999, the Veterans Administration (VA) spend $300 million to compensate over 50,000 veterans for noise-induced hearing loss, That number is expected to rise significantly.

Everyday, sounds over 85 decibels can cause some type of hearing loss. Types of these sounds include a gun shot, bombs exploding, jets taking off, power tools, and a musical concert (not just rock and roll), to name a few. However, even common, everyday items, such as a hair dryer, Walkman/IPod, lawn mower, and blender, can cause some type of NIHL. If you have stood next to someone listening to music through headphones, and you can hear the music, then that volume has reached a damaging range. If you cannot hold a conversation while a choir is singing, then that volume has reached a damaging range. Some side effects to NIHL include tinnitus (ringing in the ears), and diminished speech understanding (especially women and children’s voices). With NIHL, common sounds in our language, such as k, s, f, t, and p, can be mixed up (i.e. hearing the word cat, when someone said cap).

Unlike most other types of hearing loss, NIHL can be prevented. Because NIHL is gradual and cumulative, repeated noise traumas can impact hearing loss in a greater fashion. A noise trauma from 50 years ago can cause problems now. Many of my patients who served in the military during World War II, the Vietnam War, and even the Gulf War, are now seeing the effects of NIHL. Usually, the sensitive hair cells in our inner ears (cochlea) can recover from noise trauma, within 48-72 hours. The hearing loss can become permanent if the noise overwhelms the self-repairing function of the hair cells, and they do not recover.

So what can we do? First, avoid all types of loud noises. If it is necessary, then use some form of noise attenuators, such as ear plugs or earmuffs. Custom earplugs can be made for you in our office. Secondly, turn down the noise. Turn down the IPods, and Walkmans. The volume should not increase past the half-way mark. Finally, there is initial research to indicate that certain antioxidants and certain drugs (otoprotective agents), if taken prior to exposure, can reduce the damage done by noise. Newer studies, are working on a “morning-after noise pill” to prevent inner ear hair cell damage. However, none of these drugs will counter a healthy regimen of reducing noise.

Because NIHL creeps up gradually, it is very difficult to notice it. It is the family members, friends and co-workers who notice your hearing loss first. If you feel that you or a family member may be feeling the symptoms of NIHL, then call our office at (360) 892-9367, and I will conduct a full audiological evaluation and determine a course of action. Most NIHL patients choose a treatment option that may include the use of hearing aids. The American Medical Association concluded that 95 percent of people with hearing loss would benefit from hearing aids. If this is the only option available, I, or any audiologist, will help in the decision- making process, and stay committed to help you hear better. Turn down the noise and protect your hearing.

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Posted in AudigyCertified, Audiologist, Doctor of Audiology, Hearing Aids, Hearing Device, Hearing Difficulty, Hearing Loss, Hearing protection, Hearing Technology, Noise-induced, Treatable Hearing Loss, Uncategorized

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