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Other
Hearing Disorders:
Ménière’s Disease
Hyperacusis
Conductive Loss
Sensori-neural Loss
Otosclerosis
Acoustic Neuroma
Ménière’s
Disease:
Vertigo, roaring tinnitus, hearing loss, and a sensation of fullness or pressure
in the ears are agonizing symptoms each unto themselves. When they occur
simultaneously, they characterize Ménière’s disease, named for French
otologist Prosper Ménière who first identified the condition and noted it
correctly as a dysfunction in the inner ear.
Causes:
The cause of Ménière’s disease is not known. But the physical manifestation
of it is well known – a swelling of the inner ear labyrinths, the organs that
house the balance mechanisms. This swelling, referred to as endolymphatic
hydrops, results from an overproduction or an inadequate re-absorption of the
natural fluids (endolymph) in the labyrinths.
The Progression of Ménière’s:
In the early stages of Ménière’s, which can span a year or more, the
symptoms come and go unpredictably. The episodes (with dizziness, nausea, and
one-sided tinnitus) can last from ten minutes to all day, with residual
unsteadiness lasting several days longer. The intervals between these attacks
can be months or sometimes years.
Fortunately, the violent attacks of vertigo usually lessen then stop in the
later stages of the disease. Unfortunately, the patient’s hearing usually
worsens over time, and the typical low-frequency roaring tinnitus that was
episodic becomes permanent. Doctors refer to these permanent, leveled-off
changes as Ménière’s "burnout."
Treatments:
Ménière’s medications, such as diuretics and motion sickness drugs, are
aimed at arresting the dizziness and accompanying nausea and vomiting.
Betahistine can help control debilitating dizzy spells and is available by
prescription in the U.S. from a compounding pharmacy. None of these medications
is intended to alleviate tinnitus.
For some patients, surgery offers long-term relief from vertigo. However, some
of the more invasive surgeries, such as the cutting of the balance nerve, can
cause permanent hearing loss.
Another procedure – the injection of drugs, such as gentamicin, through the
eardrum – destroys inner ear vestibular hair cells and often ends vertigo.
Patients can help reduce the frequency of Ménière’s attacks by eating small
meals throughout the day, avoiding the food additive MSG, and reducing salt in
the diet.
Ménière’s patients can usually find tinnitus relief by wearing carefully
fitted hearing aids and adding steady low-level sounds to their environment.
Hyperacusis:
Hyperacusis is an abnormal intolerance to ordinary sounds. For the person with a
severe form of this condition, an everyday noise – like that from a dish being
placed on a table – can be far too loud, even excruciatingly loud. Hearing
loss and hyperacusis seldom occur simultaneously. Statistically, though, 90% of
those who have hyperacusis also experience tinnitus – a constant ringing or
other distressing noise in the ears or head.
Causes:
Excessive noise exposure appears to be a cause of this disorder. Some people
report that their hyperacusis began immediately following a single exposure to
intense noise, like that from a gun shot blast or an air bag deployment. Others
became sound sensitive from long-term noise exposure. Hyperacusis patients find
that their condition is worsened not only when they are exposed to noise, but
also when they go too far to protect their ears from it. Silence can worsen the
condition.
Head injury, Bell’s Palsy, chronic fatigue syndrome, epilepsy, Lyme disease,
and drug side effects have all been associated with hyperacusis.
Although the exact point of injury and the mechanism responsible for hyperacusis
are not definitively known, most researchers believe that hyperacusis ultimately
is the result of a dysfunction in the brain’s sound regulatory mechanism.
Treatments:
Sound desensitization treatment techniques have helped many hyperacusis patients
become more tolerant of sound. The low-frequency (200 to 6000 Hz) pink noise
protocol requires the hyperacusis patient to listen to pink noise set at a
volume just below the individual’s discomfort level for two hours per day.
Improved loudness tolerance might not be seen for many months. With tinnitus
retraining therapy (TRT), a patient wears two hearing aid-like noise generators,
set at a barely audible, broadband level for 8-10 hours per day for up to 24
months. Many hyperacusis and tinnitus patients who use TRT find that the symptom
of hyperacusis improves more quickly than the tinnitus – usually within six
months.
Hearing
Loss:
Sensori-neural hearing loss:
Sensori-neural hearing loss is caused by external events, such as exposure to
noise or ototoxic drugs, which can damage or destroy inner ear structures
(cochlea, semicircular canals) or nerves along the auditory pathway to the
brain. Excessive noise exposure is the second most common cause of
sensori-neural
hearing loss.
Presbyacousis is the age-related degeneration of the inner ear. It is the most
common cause of sensori-neural hearing loss in adults. Thirty percent of those 65
to 70 years old and 40% of those over 75 years old have Presbyacousis.
Hearing aids, most especially the digital variety, can help sensori-neural
hearing loss.
Conductive Hearing Loss:
Sound waves are conducted to the inner ear either by air (through the ear canal)
or by bone (through the skull and the bones in the middle ear). Conductive
hearing loss is caused by something that stops incoming sound from traveling
through the outer or middle ear on its way to the inner ear. Compacted earwax in
the ear canal or the disease of otosclerosis in which the middle ear bones to
fuse together can cause conductive hearing loss. When these conditions are
corrected, hearing levels usually return to normal, and any associated tinnitus
often lessens or goes away completely.
Otosclerosis:
When the bones in the middle ear are healthy, they vibrate and conduct sounds
from the outer ear into the inner ear. If any of the middle ear bones is
affected by otosclerosis, a disease that causes the bones to become spongy and
malfunction, the disease process can cause a conductive hearing loss and tinnitus. A
stapedectomy is a procedure in which one, two, or all of the middle ear bones
are surgically replaced with a prosthetic implant. In approximately 90% of
cases, hearing improves after this surgery. In some cases, the accompanying
tinnitus will improve after this surgery.
Acoustic Neuroma:
An acoustic neuroma is a rare, benign tumor that grows on the eighth cranial
nerve – the nerve that runs between the inner ear and the brain. The
vestibular nerve (from the balance organs) and the auditory nerve (from the
hearing organs) actually wind together to form the eighth cranial nerve.
Consequently, dizziness and one-sided hearing loss are common symptoms of an
acoustic neuroma. Other symptoms that can accompany this tumor are facial
numbness and tinnitus.
Acoustic neuromas can be removed surgically or reduced in size with radiation.
Because these tumors typically grow very slowly, many patients and doctors
prefer to watch the progress before choosing an invasive surgical procedure. The
surgery can produce some negative aftereffects, such as total deafness on the
affected side. This often causes people to take a wait-and-see approach to the
disorder. Although these tumors are usually benign, they can grow big enough to
interfere with brain function and can in very rare cases cause death.
If you have one-sided tinnitus, talk to your ENT about having an MRI to rule out this
disorder.
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