Causes of Hearing Loss
With all of the extraordinary medical advances of the past few decades, one might reasonably expect that medical professionals would be able to enumerate the causes of deafness. It’s true that they can recite a long list of things that can cause deafness. But it’s also surprising how often they are unable to identify the specific cause of a specific person’s deafness.
Research is continuing in this area, and progress is being made. In the near future, today’s common story that no one knows why a particular person is deaf may be a thing of the past. In the meantime, here is some information on some of the causes of deafness.
There are basically two types of deafness. One is caused by problems with the sound reaching the inner ear. Since the sound travels there via conduction, this is called conductive hearing loss. It’s the far less common mechanism of hearing loss.
Much more common is sensorineural hearing loss. This is often called nerve deafness, but this is a misnomer, because the auditory nerve is almost never the cause. The problem is usually in the hair cells of the cochlea. One of the most devastating and mysterious forms of sensorineural hearing loss is sudden hearing loss or sudden deafness!
So what causes sensorineural hearing loss? Well, lots of things, many of which we can’t do much about. One big thing that we can control is noise. Noise is the enemy of hearing, and people are discovering that it doesn’t take as much noise as previously thought to cause temporary or permanent hearing loss. Here’s a bunch of information on Noise Induced Hearing Loss (NIHL).
Another surprisingly common cause of hearing loss is ototoxicity – the ability of drugs and medications to cause hearing loss.
Genetic factors have also been identified as causes of hearing loss.
Does aging cause hearing loss?
Do female hormonal changes cause hearing loss?
June 2000 – Scientists have recently discovered a chemical that not only is crucial to the hearing process, but might also have profound impact on unrelated aspects of science.
October 2004 – There’s been a long controversy regarding cell phone use causing cancer. Now there seems to be some evidence that long term cell phone use can cause acoustic neuromas – which cause deafness!
June 2005 – Do airbags cause hearing loss?
June 2005 – You know that noise can cause hearing loss. But did you know that the presence of carbon monoxide appears to increase the detrimental effect of noise on hearing?
January 2006 – We all know that exposure to loud noise can cause sensorineural hearing loss. Now there’s evidence that it can cause acoustic neuromas, as well! Here’s the story!
February 2006 – When hearing is lost in the brain
March 2006 – Tumor growth related to exposure to noise
March 2006 – A recent Mayo Clinic study contradicts a previous study indicating that arthritis increases the risk of hearing loss.
March 2006 – Scientists at the University of Michigan report new acoustic neuroma surgery that’s less damaging to hearing.
April 2006 – Can air bag deployment damage auditory function?
April 2006 – The presence of carbon monoxide seems to intensify hearing loss due to noise.
May 2006 – Drinking red wine may help prevent deafness
May 2006 – Inner Ear May Take Beating From High-Impact Aerobics
July 2006 – Nicotine Exposure During Fetal Development Leads To Hearing Problems
August 2006 – Protein Tied to Usher Syndrome May Be Hearing’s “Missing Link”
September 2006 – Children with Meningitis Should Have Early Hearing Test
November 2006 – Acoustic Shock Threatens Call Centre Staff
February 2007 – Car Airbags Will Cause Permanent Hearing Loss in 17 percent, Study Predicts
February 2007 – The Molecular Sound of Silence
June 2007 – Diabetics at Increased Risk of Hearing Loss
July 2007 – Smoking and Noise Result in Increased Hearing Loss
July 2007 – VHL Can Cause Sudden Hearing Loss
July 2007 – New Acoustic Neuroma Web Site
August 2007 – Psychogenic Hearing Loss: Detection Crucial to Proper Treatment
August 2007 – Auditory Neuropathy/Auditory Dys-synchrony
September 2007 – Diabetics at Increased Risk of Hearing Loss
October 2007 – Drinking may dampen hearing in the short term
October 2007 – Treating an acoustic neuroma
December 2007 – Occupational noise not linked to increased risk of acoustic neuroma
December 2007 – Here’s a Great Superficial Siderosis Site
December 2007 – Cholesterol Fine Tunes Hearing
January 2008 – Airbags and Ear Damage
January 2008 – OTC Eardrops May Cause Hearing Loss or Damage
January 2008 – Deafness and Seizures Result When Mysterious Protein Deleted in Mice
March 2008 – Common Virus Causes Hearing Loss in Fetus
March 2008 – Treatment of rare condition will cause woman to go deaf
March 2008 – ‘Have Another Beer.’ ‘I SAID HAVE ANOTHER BEER!’
April 2008 – Top 5 Ways to Protect Your Hearing
June 2008 – Acoustic neuromas: Wait and see or surgery
June 2008 – Child’s kiss deafens Hicksville mom
June 2008 – Why the obese and smokers risk deafness
June 2008 – Hearing Loss Is Common in People with Diabetes
September 2008 – MRI reveals inner ear anomalies in children with hearing loss
December 2008 – Lifestyle Can Affect Hearing
January 2009 – Improved Hearing Preservation Follows Lower-Dose Radiotherapy
March 2009 – UK Study Offers Clues To Beating Hearing Loss
March 2009 – Surfer’s Ear Not to be Taken Lightly
June 2009 – Hearing, Voice Problems Worsen Seniors’ Communication Skills
June 2009 – Complications of Diabetes Also Associated with Hearing Loss
July 2009 – VEGF Inhibitor Shows Promise in NF-2
July 2009 – Sleep Apnea, Hearing Loss and Thickened Blood
July 2009 – Cardiovascular health affects hearing loss
November 2009 – Mechanisms of Noise-Induced Hair Cell Death
May 2010 – Viagra May Cause Hearing Loss
August 2010 – Omega-3 protective against hearing loss
September 2010 – Expert: Habits can lead to hearing loss
October 2010 – Adolescent Hearing Loss on the Rise
October 2010 – Meningitis: A Deafening Disease
October 2010 – Teens at Risk: Audiologists Respond
November 2010 – Hearing Loss Common Following Radiation Therapy for Head and Neck Cancer
November 2010 – Hearing loss linked to passive smoking
December 2010 – Most Acoustic Neuroma Surgeries Have Favorable Outcomes
December 2010 – Restricted Calories Decreases Hearing Loss in Mice
January 2011 – Scientists Find Key Biomarker for Autoimmune-Related Hearing Loss
February 2011 – Hearing Loss and Alcohol
February 2011 – Auditory Neuropathy in Premature Infants
March 2011 – Temporary Hearing Loss Causes
March 2011 – Heart Disease and Hearing Loss Common in Middle Age, But Both Could Be Preventable
March 2011 – Stress, Tinnitus and Hearing Loss Linked
May 2011 – Hearing Loss Is Common in People with Diabetes
August 2011 – Man Regains Hearing After Earthquake
December 2011 – Even Minimal Blood Lead Levels Associated with Hearing Loss
back to “New to Hearing Loss”
When hearing is lost in the brain
Age-related hearing loss is not just a case of the ears losing their capability. The ability of the brain to process sound is weakened as well. Modern digital hearing aids with directional microphones may solve some of these problems. The ears are still crucial for hearing, but preliminary studies in mice indicate that a decrease in certain processes in the brain may make it harder to filter out unimportant sounds. “Traditionally, scientists studying hearing problems started looking at the ear. But we are finding patients with normal ears who still have trouble understanding a conversation. There are many people who have good inner ears who just don’t hear well. That’s because their brains are aging,” said Dr. Robert D. Frisina of the University of Rochester Medical Center. Full Story
Tumor growth related to exposure to noise
The eighth cranial nerve has two branches, one that is responsible for balance and one that is responsible for hearing sensitivity. An acoustic neuroma is a non-cancerous tumor that grows on the eighth cranial nerve. The tumor typically grows very slowly and affects only one ear. Symptoms are not generally noticed until the tumor is large enough to puts pressure on nerves, causing the symptoms, including hearing loss, tinnitus, and facial weakness or numbness on the affected side, as well as dizziness or balance problems. Full Story
Dim view of aging linked to hearing loss
Older adults who harbor negative stereotypes about aging may have a more rapid decline in their hearing, a new study suggests. Researchers at Yale University found that among older men and women, between 70 and 96 years old, those who held to the stereotypes of older adults as “frail” and “senile” showed a greater decline in hearing over the next three years. The link was independent of a number of factors in hearing loss, including age, physical health and depression. The effect was seen even in study participants who had “perfect scores” on hearing tests at the study’s start, lead study author Becca R. Levy told Reuters Health. Full Story
Can air bag deployment damage auditory function?
On Monday, June 6, 2005, Lisa wrote the following on the Hearing Loss Web Forum under the topic of “Air Bags Ruined My Hearing:”
“Last week I was involved in what should have been a minor car accident. I wasn’t paying attention and ‘gently’ hit the car in front of me stopped for a light. What happened next was terrifying. The inside of the car seemed to explode in a deafening roar. I had an unimaginable pain in both ears and considerable bleeding from my ear canals. I also had a very loud ringing and was virtually deaf.” Full Story
Drinking red wine may help prevent deafness
Age-related deafness, and hearing loss caused by loud noise, may be reduced by the antioxidants in red wine, green tea and aspirin, it was claimed yesterday. The compounds they contain could help protect the delicate hairs of the inner ear that are vital to hearing, new research suggests. Destructive chemical agents called oxygen-free radicals, produced by normal cellular processes and in response to loud noise and exposure to powerful antibiotics, can damage the hairs. But antioxidants such as resveratrol, found in red wine and green tea, and salicylate, the active ingredient in aspirin, should be able to neutralise them. Full Story
Inner Ear May Take Beating From High-Impact Aerobics
PEOPLE who engage in demanding physical activities might expect to suffer occasional injuries to the body parts directly involved. But few devotees of high-impact aerobics are likely to guess that their jumping and bouncing to music could damage their inner ears, causing symptoms like persistent vertigo, dizziness, imbalance, motion sickness, ringing or fullness in the ear and high-frequency hearing loss. Yet just such a syndrome has been identified in a group of 30 otherwise healthy women in the Westchester County area of New York who regularly do high-impact aerobics, which involves a lot of bouncing up and down, often with both feet off the ground at once. Full Story
Acoustic Shock Threatens Call Centre Staff
Acoustic shocks are defined as “any temporary or permanent disturbance of the functioning of the ear, or of the nervous system, which may be caused to the user of a telephone earphone by a sudden sharp rise in the acoustic pressure produced by it”. The sound could be a whistle, a bleep – or any unexpected noise. . . . Dr Mark Downs, executive director of technology and enterprise for the Royal National Institute for the Deaf, said: “Acoustic shock is not the same as noise-induced hearing loss and is believed to occur at sound pressure levels below those which present an immediate risk to hearing damage. “It is still a relatively un-researched condition and RNID welcomes public debate on the issue.” Full Story
The Molecular Sound of Silence
“(Hearing) is a very complicated process where lots of things can go wrong,” Wong said. “What we have done is study one of those things.” That thing is a mutation in a type of protein molecule called espin, a “binder” or “linker” protein common in nature, particularly in sensing cells. In the ear’s hair cells, espin links rod-like protein molecules called filamentous actin, or F-actin, into bundles, Wong said. The problem occurs when a mutated form of espin – which needs binding sites on both sides, kind of like double-stick tape, to function properly – fails to secure the F-actin bundles tightly. Full Story
Diabetics at Increased Risk of Hearing Loss
Diabetics have twice the risk of developing hearing loss as are nondiabetics, researchers reported here at the American Diabetes Association 67th Scientific Sessions (ADA). . . . . “The pathologic changes that accompany diabetes could plausibly affect the vasculature or the neural system of the inner ear, resulting in sensorineural hearing impairment,” Dr. Cowie explained in a presentation on June 24th. . . . . After adjusting for age, 31.6% of self-reported diabetics had hearing impairment at the lower frequency range versus 14.5% of the nondiabetics subjects. The figures were 56.8% and 35.8% for the two groups, respectively, at the higher frequency range. Full Story
VHL Can Cause Sudden Hearing Loss
Patients with the genetic disorder von Hippel-Lindau (VHL) disease may suddenly experience hearing loss because of a tumor-associated hemorrhage in the inner ear, according to a study in the July 4 issue of the Journal of the American Medical Assocation (JAMA). Endolymphatic sac tumors (ELSTs; tumors of the inner ear) occur sporadically but may be associated with von Hippel-Lindau disease (a genetic disease characterized by the development of blood vessel tumors in the retina of the eye and in the brain; lesions and cysts can also develop in other parts of the body). ELSTs are associated with significant dysfunction of hearing and balance, including sudden irreversible hearing loss. The mechanisms and appropriate treatments for this disorder are not well understood. Full Story
New Acoustic Neuroma Web Site
Editor: Acoustic Neuromas are fairly common causes of hearing loss, but most people know very little about them. Here’s a bit of information on acoustic neuromas and a new website that offers additional help.
The Acoustic Neuroma Association (ANA) has launched a new medical Web site listing http://www.anausa.org/index.html for newly diagnosed and current acoustic neuroma patients. ANA is a non-profit organization with the mission to inform, educate and provide national and local support networks for those affected by acoustic neuromas, and to be an essential resource for health care professionals who treat the condition. Founded by Virginia Fickel Her, a patient, the AHA has been a source of information and support for acoustic neuroma patients for over 25 years, and oversees over 50 local support groups around the country.
An acoustic neuroma (sometimes termed a vestibular schwannoma) is a benign brain tumor on the eighth cranial nerve, which leads from the brain to the inner ear. Typical symptoms include hearing loss, balance issues, tinnitus and a feeling of fullness in the ear. The most common forms of treatment are surgery, radiation or “watch and wait.”
According to Judy Vitucci, executive director of ANA, “The new medical Web site listing is designed to provide up-to-date information regarding the most important question for a new patient — where do I find a qualified physician?” She added, “Although this is a rare type of tumor, recent studies show that acoustic neuroma diagnoses are increasing, and most patients are between the ages of 30 and 60.”
The new Web site will provide patients with a tool to help them find qualified medical professionals across the country. The site also provides information on the various types of treatment. Additionally, users can fill in the “contact us” information, and ANA will send them a packet of information with referrals of former patients who can provide support. Visit http://www.anausa.org/index.html for more information.
Psychogenic Hearing Loss: Detection Crucial to Proper Treatment
Psychogenic hearing loss, also known as pseudohypacusis, non-organic or functional, originates in the mind of an individual and is thereby psychological rather than physiological in nature. The loss may be classified either as intentional and based on underlying motives such as monetary compensation or sympathy needs or unintentional and based on underlying stress or anxiety. The detection of psychogenic hearing loss has long been the concern of audiologists. Full Story
Auditory Neuropathy/Auditory Dys-synchrony
A little more than a decade ago, researchers led by Arnold Starr of the Department of Neurology at the University of California, described hearing impairments in ten young patients that were compatible with a disorder of the auditory portion of the 8th cranial nerve.1 The disorder was and continues to be characterized by normal cochlear outer hair cell function, absent or abnormal auditory brainstem responses (ABR), and unexpectedly poor speech discrimination. Later, eight of the patients developed evidence for a peripheral neuropathy, and the researchers suggested that “this type of hearing impairment is due to a disorder of auditory nerve function and may have, as one of its causes, a neuropathy of the auditory nerve, occurring either in isolation or as part of a generalized neuropathic process.” The use of the term “auditory neuropathy” to designate this particular profile of hearing disorders remains debatable, and doubts remain whether the condition represents a true auditory nerve neuropathy. The loss of neural synchrony of auditory nerve fibers leads to the view that the term “auditory dys-synchrony” may provide “a more comprehensive view of auditory neuropathy that connects logically to viable management options. Full Story
Diabetics at Increased Risk of Hearing Loss
Diabetics have twice the risk of developing hearing loss as are nondiabetics.
Catherine C. Cowie, PhD, director, diabetes epidemiology program, National Institute of Diabetes and Digestive and Kidney Diseases, reported data in 5,140 individuals aged 20 to 69 years who underwent audiometric testing from 1999 through 2004 as part of the National Health and Nutrition Examination Survey (NHANES). “The pathologic changes that accompany diabetes could plausibly affect the vasculature or the neural system of the inner ear, resulting in sensorineural hearing impairment,” Dr. Cowie explained in a presentation. In the NHANES trial, pure tone thresholds over lower frequency were obtained for each ear at 500, 1000, 2000, 3000, 4000, 6000, and 8000 Hz using a calibrated audiometer in a soundproof booth. A pure tone average exceeding 25 decibels over a given frequency range in both ears indicated hearing impairment. Full Story
Drinking may dampen hearing in the short term
If you have a hard time hearing conversation at a bar, it may not be because of the noise, a study suggests. Alcohol, UK researchers found, seems to temporarily drain a person’s hearing — particularly when it comes to discerning the sounds of conversation. In a study of 30 healthy volunteers, they found that as participants drank, their hearing became less acute. Lower-frequency hearing, which is necessary for discerning speech, suffered the most, the researchers report in the online journal BMC Ear, Nose and Throat Disorders. Full Story
Treating an acoustic neuroma
DEAR MAYO CLINIC: I’m 59 and have been diagnosed with an acoustic neuroma. I have been to a surgeon and his explanation of the surgical procedure has me so frightened that I have chosen to do nothing. I have many bouts of dizziness and some hearing loss. Could you better explain the surgery as well as the benefit or drawbacks of radiation? Full Story
Occupational noise not linked to increased risk of acoustic neuroma
Contradicting some prior reports, new study results do not demonstrate an increased risk of acoustic neuroma related to occupational noise exposure. “A small number of prior epidemiologic studies of occupational noise exposure based on self-report have suggested an association with acoustic neuroma,” Dr. Colin Edwards, of Ohio State University, Columbus, and colleagues write in the December 1st issue of the American Journal of Epidemiology. The researchers examined the putative association in a register-based case-control study. A total of 793 acoustic neuroma cases were identified between 1987 and 1999 from the Swedish Cancer Registry, and these were matched to 101,756 control subjects randomly selected from the Swedish Population Registry. Full Story
Here’s a Great Superficial Siderosis Site
Editor: I met Dave Hill online several years ago when he posted to the Hearing Loss Web Forum. Dave has superficial siderosis (SS), and he was interested in helping others who also had that condition. So he developed a website and had soon gathered a community of SS survivors. Here’s Dave with a bit about SS and his site.
www.superficialsiderosis.org.nz is a site written by a Superficial Siderosis survivor, Dave Hill of New Zealand, for fellow survivors. It has been praised by published Neurologists for its ability to describe the medical condition in plain understandable English.
Superficial Siderosis is a rare condition which in almost every case reduces the patient’s hearing to zero, produces quite unstable balance and coordination, vision complications, plus up to 15 – 20 other associated sideline effects depending on the recipient. Many patients are confined to a wheelchair for mobility, some bedridden.
As a result of Central Nervous System bleeding which congregates around the brain’s cerebellum, over a varying period of time the blood forms into an iron salt casing, stopping brain movement in both directions. There is nothing currently known to man to eliminate the problem.
Airbags and Ear Damage
A 2007 study predicts that airbag deployment in automobile accidents leads to permanent hearing loss in 17 percent of those exposed.1 The prediction is based upon the Auditory Hazard Assessment Algorithm for the Human (AHAAH), a mathematical computer model of the ear which, according to the author of the study, is “designed to reproduce the ear’s physiological response to virtually any intense sounds and to predict hazard from calculated displacements in the inner ear.” These surprisingly high estimates of permanent sensorineural hearing loss, based on a computer model with 95 percent accuracy, bring to the forefront again the dangers of airbag deployment to the ear in the more than 6 million automobile accidents per year in the United States alone. Even minor bumper-benders in slow speed collisions, representing little or no danger of injury to occupants who are safely buckled up, can cause the airbag to inflate. Rushing toward startled drivers and passengers at speeds of 180 mph and with noise levels of 170 dB or more, airbags can cause many other otologic injuries in addition to permanent hearing loss. Full Story
Common Virus Causes Hearing Loss in Fetus
A virus that infects up to 85 percent of adults in the U.S. by age 40 is also the virus most frequently transmitted to a child before birth. For most adults, the virus goes unnoticed, but for babies it can be life-changing. Now, thanks to a $1 million grant, Carolinas Medical Center is studying the virus and its relationship to hearing loss in newborns. By all accounts, six-month-old Sydney is healthy, but thanks to an infection called congenital Cytomegalovirus, or CMV, silence could be what Sydney hears down the road. The CMV virus is carried by the mother and spreads to the child during pregnancy. “And if a baby develops that infection before they are born then they can be effected with hearing loss developmental delay, with all sorts of complications,” explained pediatrician Dr. Amina Ahmed of Carolinas Medical Center. Full Story
Treatment of rare condition will cause woman to go deaf
Researchers may be coming close to the cure for Neurofibromatosis (NF), a disease that is about to drastically change a Muskegon woman’s life forever. It’s a rare condition but it’s thousands across the country have it, affecting each patient differently. The disease is life changing and can be fatal. Those who suffer get tumors that don’t stop growing. “Patients who have neurofibromatosis can develop these tumors. They’re not cancerous tumors, they don’t spread through the body and things like that, but they do grow in one spot and cause problems,” said Dr. Al Cornelius of Spectrum Health, an NF researcher. [. . . ] Cornelius is preparing for a clinical trial that will take place in Grand Rapids at the DeVos Children’s Hospital. He’s hoping that his findings will provide answers and solutions for the 100,000 Americans who suffer from the condition and says so far results are looking promising. [. . . ] Jessica’s surgery is next month. It may be the most crucial of them all because when she comes out she’ll be changed forever. “I’m getting ready for a surgery on the right side to remove the other acoustic neuroma and it will result in me being deaf,” she said. Full Story
‘Have Another Beer.’ ‘I SAID HAVE ANOTHER BEER!’
Ever notice that when you’re at a social gathering, private home or down at the neighborhood watering hole, and you’re designated the designated driver (Yes, I’ll have a cranberry spritzer. I have to drive this crew home later.), just how loud everyone talks. And as the libations flow freely, the sound just gets louder and louder and LOUDER! Well, you might think that it’s the tequila shooters loosening up the party-goers that brings that volume to such high levels – and that’s part of it. But it’s not just high spirits that pumps up the volume. Drinking alcohol lessens your ability to hear. “What’d ya say?” True story. British researchers at the University College of London Hospitals, lead by Tahwinder Upile, studied a group of 30 healthy adults, tested their hearing levels sober and as they consumed alcohol and discovered that as the subjects drank, their hearing became “less acute.” Full Story
Acoustic neuromas: Wait and see or surgery
An acoustic neuroma (vestibular schwannoma) is a benign, slow growing, well encapsulated tumor arising from the sheath surrounding the 8th cranial nerve. The 8th cranial nerve, the acoustic nerve, is comprised of two nerve branches: one controls balance (vestibular) and the other hearing (auditory). (See Cranial nerves .) Most acoustic neuromas start within the internal auditory canal and extend into the cerebellopontine angle (CPA), pressing on the brain stem. . . . The earliest symptom of an acoustic neuroma is gradual hearing loss due to the progressive growth of the tumor in the internal ear canal. Hearing loss is usually characterized by a distortion in perception and acuity of sound. Patients present with tinnitus (a roaring, buzzing, or hissing sound) that may be intermittent or constant. As the tumor grows, there may be balance disturbances, vertigo with sudden changes in position, headaches, and facial or ear pain. These symptoms are the result of the compression and stretching of cranial nerves, although the brain compensates for the unsteadiness, so symptoms of balance disturbance may be ignored. Constant or intermittent facial tingling or numbness may be another sign related to nerve compression. Full Story
Child’s kiss deafens Hicksville mom
This is a story about a kiss – an expression of love so potent from a little girl – that it caused her mother not only to lose her hearing after a buss on the ear, but to be thrust into the pages of medical history. Yet it wasn’t the sound of the smackaroo that damaged the hearing of Hicksville homemaker Gail Schwartzman, but a suction force that displaced the woman’s eardrum, paralyzed a tiny trio of bones and left residual sounds in her head. Schwartzman’s case will be the subject of a medical journal report within the coming weeks, outlining for the first time what the author calls “the kiss of deaf.” Schwartzman describes the kiss as physically painful but says it has left a deeper emotional scar on her daughter. Even as she recounted details of the buss planted two years ago, the child, now 6, broke into tears, apologizing to her mom. Schwartzman requested that her daughter’s name not be published. Full Story
Why the obese and smokers risk deafness
Perhaps unsurprisingly, noise exposure, known to destroy the sound-transducing hair cells in the inner ear, was the biggest risk. More surprising is the apparent effect of smoking and overeating. These factors have been suspected as potential causes of deafness, but it has been hard to separate them from the effects of cardiovascular diseases that are also frequently suffered by people who smoke and overeat. This study has been able to do just that. Full Story
Lifestyle Can Affect Hearing
The damaging effects of aging and noise exposure on hearing are well established. Other factors have been studied over the years, but their association to hearing loss remains open to debate. Here are the latest findings on four of these variables: smoking, obesity, diabetes, and alcohol (SODA). Full Story
Improved Hearing Preservation Follows Lower-Dose Radiotherapy
Researchers at Thomas Jefferson University have found that a lower dose of fractionated stereotactic radiotherapy for acoustic neuromas results in better hearing preservation and has the same tumor local control rate as a higher dose of therapy. The study appeared online in the International Journal of Radiation Oncology•Biology•Physics. “We previously had not determined the optimal dose of fractionated stereotactic radiotherapy for acoustic neuromas,” said David W. Andrews, MD, professor and vice-chairman of the Department of Neurological Surgery at Jefferson Medical College of Thomas Jefferson University, and the lead author. “This study was designed to compare the hearing preservation between the two doses. The lower-dose treatment resulted in a 100% tumor control rate, with the advantage of better hearing preservation.” Full Story
UK Study Offers Clues To Beating Hearing Loss
Researchers at the University of Leeds have made a significant step forward in understanding the causes of some forms of deafness. The Leeds team has discovered that the myosin 7 motor protein — found in the tiny hairs of the inner ear that pick up sound — moves and works in a different way from many other myosins. “We’re really excited by this discovery as it could lead to new insights into certain forms of deafness,” says Dr. Michelle Peckham from the University of Leeds’ Faculty of Biological Sciences. “Mutations in this protein have been linked to hearing loss, particularly of the type connected to Usher syndrome, which is a form of degenerative deaf-blindness.” There are around 40 myosin motor proteins in the human body, the most familiar of which is the type of myosin found in skeletal and heart muscle. But all cells have many different kinds of myosin. Full Story
Surfer’s Ear Not to be Taken Lightly
But there is a more serious condition that can affect a surfer’s hearing, one that is unique to places like the East End – surfer’s ear, or “exostosis of the external auditory canal” in medical lingo. What happens in this condition is that repeated exposure to cold water and wind stimulates bone growth that narrows the external ear canal and gradually blocks the eardrum. This narrowing traps water and earwax in the canal, eventually resulting in painful chronic ear infections and even hearing loss. My good friend Scott Bradley, senior vice president at Cook, Hall, and Hyde, has been surfing for 38 years. He is a surfing instructor and has traveled the world looking for the perfect wave. He was never aware that there could be a risk to his ears and hearing until about 18 years ago. He was diagnosed with surfer’s ear at that time. Full Story
Complications of Diabetes Also Associated with Hearing Loss
Diabetic patients with poor glycemic control or vascular or neuropathic complications may also suffer from hearing loss, researchers here said. High-frequency sensorineural hearing impairment is a common but underdiagnosed complication of diabetes, according to two studies presented at a poster session at the American Diabetes Association meeting here. “That makes sense, since [patients with diabetes] already have nerve damage in other areas,” said Vivian Fonseca, M.D., of Tulane University and the Scott and White Clinic at Texas A&M University, who was not involved in either study. “Here you’re also seeing damage in auditory nerves.” Full Story
VEGF Inhibitor Shows Promise in NF-2
A majority of patients with type 2 neurofibromatosis had objective tumor responses to treatment with bevacizumab (Avastin), data from a small clinical trial showed. Four of 10 patients had improved hearing, and two others had stable hearing during treatment, Scott Plotkin, MD, PhD, of Massachusetts General Hospital in Boston, and colleagues reported online in the New England Journal of Medicine. Tumor responses remained durable in some patients during follow-up of 11 to 16 months. “This kind of treatment response is unprecedented,” Dr. Plotkin said in a statement. “Our study is the first to provide evidence that a drug can shrink vestibular schwannomas . . . and the first to show that patients’ hearing can be improved.” Full Story
Sleep Apnea, Hearing Loss and Thickened Blood
I came across this interesting article (http://tinyurl.com/m92dah) in Sleep Medicine, where they showed that in patients with obstructive sleep apnea, a significant number were hemodynamically hyperviscosity positive (282/610 patients). Hyperviscous means that blood is thicker and more prone to clog arteries. Of these 282 patients, 239 had brainstem AEP abnormalities. AEPs are tests for ear neurologic reflexes where clicks are given in one ear and brain waves are measured in response. It tests for inner ear and brainstem function. Ones that didn’t have hyperviscosity all had normal AEPs. Of these 239 patients, 57 had bilateral sensorineural hearing changes (no waves at all), and 182 patients had significant bilateral signal changes. After 6 months of CPAP, hyperviscosity was normalized in 159 patients. In 112 of these 159 patients a repeat AEP became normal. Of the 80 patients on CPAP that did not normalize, hemodilution therapy resulted in normalization in 61 patients. Hemodilution is when blood is made thinner by removing some blood and adding some saline. Full Story
Cardiovascular health affects hearing loss
You don’t have to be a cardiologist to know that the heart – and cardiovascular system in general – affects many organs in your body. If the heart is not healthy, it impacts your circulation, respiratory system, kidneys and liver function, brain, and yes, even hearing. Now, you may be wondering what the connection between the heart and your ears is, and how a healthy (or weakened) cardiovascular system could possibly have an effect on your hearing. <snip> And then there is cardio-vascular disease (CVD), also a well-known factor in hearing loss. There’s plenty of scientific evidence to back up this claim. Full Story
Omega-3 protective against hearing loss
The study findings revealed that a least two servings of fish weekly is related to a cut down of 42 per cent in the risk of developing hearing loss in adults over 50 years of age, as compared to those who consume less than one serving per week. Consumption of long-chain omega-3 fatty acids also yielded similar risk cut down, and there was a cut down of 14 per cent in the risk of hearing loss with higher consumption. The researchers reported, “Dietary intervention with omega-3 polyunsaturated fatty acids could prevent or delay the development of age-related hearing loss.” Full Story
Expert: Habits can lead to hearing loss
Hearing loss is a growing concern for doctors and patients alike. A recent study in the Journal of American Medical Association showed a 30 percent rise in hearing loss among teens in the last 15 years. Hearing health care specialist Randy Holyfield, with Revive Hearing, said the number one factor in the growing rate is personal music devices but added that other factors also play a part. “There are causes of hearing loss other than noise exposure – medications, smoking and nutrition. These are all things we can control,” said Holyfield, who has an office in Seguin. Foods with high concentrations of sodium and MSG are hard on the central nervous system, he said. Full Story
Adolescent Hearing Loss on the Rise
Josef Shargorodsky, M.D., and colleagues analyzed data from the annual National Health and Nutrition Examination Survey and compared the record of the softest sounds that could be heard by American 12- to 19-year-olds in 1988 through 1994 with those recorded from adolescents of the same age in 2005 and 2006. Their fi ndings, published in the August 18 issue of the Journal of the American Medical Association (JAMA), indicate that the prevalence of hearing loss increased from 14.9 percent in 1988-1994, to 19.5 percent in 2005-2006. The percentages of teens with “slight” (between 15 and 25 dB) and “mild” (greater than 25 dB) hearing loss also increased during this time frame. What are possible reasons for these increases in hearing loss among our nation’s children? One difference between the groups emerged in the JAMA report: 55 percent of children in 1988 through 1994 reported a history of three or more ear infections in their lifetime; this prevalence increased to 61 percent for children surveyed in 2005 to 2006. A greater number of ear infections might contribute to the higher prevalence of hearing loss seen in the more recently surveyed teens. Because these children exhibited more high-frequency hearing loss than their 1988-1994 counterparts, it is also possible that they experienced more exposure to loud sounds and are starting to develop noise-induced hearing loss. Full Story
Meningitis: A Deafening Disease
Hearing loss stems from a variety of sources, including age, genetics, embryologic development, infection and trauma. Congenital hearing loss that is, hearing loss at birth occurs in two to three out of every 1,000 infants. Congenital hearing loss can be caused by a genetic condition or an infection to which the mother or infant was exposed. In addition to these intrauterine and neonatal infections, people of all ages can acquire infections that may lead to hearing loss. Sometimes the infection damages hearing while other times the treatment may be the culprit, such as when ototoxic antibiotics are used (read “The Ototoxic Drug Dilemma: You Live, Hair Cells Die” from the Summer 2010 issue of Hearing Health, online at www.drf.org). Among infections that can cause hearing impairment, meningitis is the most common. At least some degree of hearing loss has been reported in up to 29 percent of bacterial meningitis cases, with a portion of these resulting in profound deafness. Meningitis is an infection of the lining (the meninges) and fl uid around the brain and spinal column. These infections can spread quickly, leading to signifi cant illness and even death. While meningitis can affect people of all ages, those most affected and negatively impacted by this disease are individuals under the age of 20 years. A recent review (May 2010) by Karen Edmond, Ph.D., found that children younger than fi ve years of age were twice as likely to develop associated chronic conditions compared to older individuals. Elderly people and people with compromised immune systems are also at increased risk of meningitis. Full Story
Teens at Risk: Audiologists Respond
Audiologists are weighing in on the research on teen hearing loss published two months ago in the Journal of the American Medical Association (JAMA) and its implications for the profession. The study, described in Part 1 of this series (The ASHA Leader, Sept. 21), showed a 31% overall rise in the prevalence of hearing loss in teens aged 12 to 19 from 1988-1994 to 2005-2006. Most of the hearing loss was slight, between 15 and 25 dB-but the prevalence of mild and worse (25 dB or greater) hearing loss increased 77%. The study also found that unilateral hearing loss was more common than bilateral (for reasons unknown), and that individuals reporting an income below the national poverty level in the 2005-2006 survey cycle had a significant risk of hearing loss. [snip] The ASHA Leader interviewed six audiologists in a variety of settings-private practice, academia, occupational audiology, and educational audiology-for their perspectives on the impact of potentially accelerated hearing loss in the rising generation, and for their ideas for next steps audiologists can take to continue to play a visible role in addressing the problem of noise-induced hearing loss. Full Story
Hearing loss linked to passive smoking
People who are exposed to the second-hand smoke from others’ cigarettes are at increased risk of hearing loss, experts believe. Doctors already know that people who smoke can damage their hearing. The latest study in the journal Tobacco Control, involving more than 3,000 US adults, suggests the same is true of passive smoking. Experts believe tobacco smoke may disrupt blood flow in the small vessels of the ear. This could starve the organ of oxygen and lead to a build up of toxic waste, causing damage. The harm is different to that caused by noise exposure or simple ageing. Full Story
Hearing Loss and Alcohol
If you’ve ever had a drink in a noisy bar, you may have noticedthat the noise level seemed to increase as the evening wore on and more drinks were consumed. “Cocktail party deafness” not only causes drinkers to speak louder so they can be heard, it can also result in a morning-after sensation of mild hearing loss. British researchers, led by Tahwinder Upile, M.D., of University College London, have found that consuming alcohol immediately reduces a person’s ability to hear, at least in the short term. Thirty volunteers had their hearing tested before beginning to drink. They then drank the same amount of alcohol, and had their hearing tested again. According to the study, published in BMC Ear, Nose and Throat Disorders in 2007, “alcohol increased the hearing threshold in all individuals.” In other words, the minimum volume a drinker needed to be able to hear grew. What’s more, they found that “alcohol specifically blunts lower frequencies affecting mostly 1000Hz, which is the most crucial frequency for speech discrimination.” Within a week, however, hearing appeared to have returned to its prior level. Full Story
Temporary Hearing Loss Causes
When one notices temporary hearing loss, it can be quite a scary experience. There are a number of reasons why it is possible to lose the ability to hear, so finding out the reason for hearing loss is the key to restoring it. Luckily, many of the reasons why this type of hearing loss occurs are due to situations that can be quickly remedied. Full Story
Stress, Tinnitus and Hearing Loss Linked
According to the World Health Organization, hearing loss will become one of the most common disabilities in the near future. To find out why hearing loss is on the rise, researchers have begun studying what factors contribute to deteriorating hearing abilities. What they found might surprise you. Full Story
Man Regains Hearing After Earthquake
But on Tuesday, something strange happened while his four children were visiting and that massive earthquake rocked the region. When it was over, Valderzak, who sat in silence for months, sat up in his bed and told his kids, “I said, you know, my hearing is back. I can hear everything, people in the hallway.” As he was shaking around in his bed, something happened in his head, and he could hear and talk again. Full story
Even Minimal Blood Lead Levels Associated with Hearing Loss
A study published in the December, 2011 issue of the Archives of Otolaryngology – Head & Neck Surgery indicates that blood lead levels that are below the current recommended action level are associated with substantially increased odds of high-frequency hearing loss. According to the abstract, the researchers evaluated the cross-sectional associations between blood lead, blood mercury, and urinary cadmium and arsenic levels and audiometrically determined hearing loss in participants aged 12 to 19 years in the 2005-2008 National Health and Nutrition Examination Survey. Of this group, there were 2535 individuals available for analysis of blood lead and mercury levels, 878 for urinary cadmium levels, and 875 for urinary arsenic levels. The results showed that a blood lead level greater than or equal to 2 µg/dL compared with less than 1 µg/dL was associated with increased odds of high-frequency hearing loss. Full Story