Hearing loss is also known as:

• decreased hearing
• deafness
• loss of hearing
• conductive hearing loss

How Hearing Works

There are three main parts to the ear: the outer ear, middle ear, and inner ear. The hearing process includes these basic steps.

• Hearing begins when sound waves pass through the outer ear to the eardrum (a thin piece of skin between your outer and middle ear).
• When the sound waves reach the eardrum, the eardrum vibrates.
• The eardrum and the three bones of the middle ear (the hammer, anvil, and stirrup, together called the ossicles) then work together to increase the vibrations as the sound waves travel onward to the inner ear.
• When the sound waves reach the inner ear, they travel through the fluids of the cochlea. The cochlea is an inner-ear structure sometimes described as being snail-shaped (Mayo, 2011).
• In the cochlea are nerve cells with thousands of mini hairs attached to them. These hairs help to convert the sound wave vibrations into electrical signals that are then communicated to your brain.
• Your brain then interprets these electrical signals as sound. Different sound vibrations create different reactions in these tiny hairs; thereby signaling different sounds to your brain.

What Are the Common Underlying Causes of Hearing Loss?

The American Speech-Language-Hearing Association (ASHA) reports that there are three basic types of hearing loss, each caused by different underlying factors. The three most common causes of decreased hearing include conductive hearing loss, sensorineural hearing loss (SNHL), and mixed hearing loss (ASHA).

Conductive Hearing Loss

This type of hearing loss occurs when sounds are not able to travel from the outer ear to the eardrum and the bones of the middle ear. When this type of hearing loss occurs, you may find it difficult to hear soft or muffled sounds. Conductive hearing loss can be treated through medical interventions and is not always permanent. Treatment may include antibiotics or surgical interventions, such as a cochlear implant. A cochlear implant is a small electrical machine (placed under your skin behind the ear) that translates sound vibrations into electrical signals that your brain can then interpret as meaningful sound.

Conductive hearing loss can be caused by:

• ear infections (otitis media)
• allergies (serous otitis media)
• swimmer’s ear (otitis externa)
• a buildup of wax in the ear
• a foreign object that has become stuck in the ear
• benign tumors
• scarring of the ear canal due to recurrent infections

Sensorineural Hearing Loss (SNHL)

This type of hearing loss happens when there is damage to inner ear structures or in the nerve pathways to the brain. This type of hearing loss is usually permanent. SNHL makes even distinct, normal-to-loud sounds seem muffled or unclear.

• birth defects that alter the structure of the ear
• aging
• working around loud noises
• trauma to the head or skull
• infections that damaged the nerves of the ear, such as measles, meningitis, mumps, or scarlet fever
• acoustic neuroma (a noncancerous tumor that grows on the nerve that connects the ear to the brain, known as the vestibular cochlear nerve)
• Meniere’s disease (a disorder of the inner ear that can affect hearing and balance)

Some medications, called ototoxic medications, may also cause SNHL. According to the American Speech-Language-Hearing Association, there are over 200 medications (over-the-counter and prescription) that may cause hearing loss. If you are taking medications for cancer, heart disease, or a serious infection, talk with your doctor about the hearing risks involved with each (ASHA).

However, if you experience any of the following symptoms, you should contact your doctor:

• hearing loss that interferes with your daily activities
• hearing loss that interferes with your daily activities
• hearing loss that is worse in one ear
• sudden hearing loss
• having ear pain along with hearing problems
• ringing in the ear
• severe hearing loss
• headaches, numbness, or weakness

If you experience headaches, numbness or weakness, coupled with chills, quick breathing, neck stiffness, vomiting, sensitivity to light, or mental agitation, you should seek emergency medical treatment. These symptoms may be associated with life-threatening conditions, such as meningitis, that warrant immediate medical attention.

How Can the Symptoms of Hearing Loss Be Treated?

If you develop hearing loss that is due to a buildup of wax in the ear canal, you can remove the wax at home. Over-the-counter solutions, including wax softeners, can be used to remove wax from the ear. Syringes can also be used to push warm water through the ear canal to remove the wax. If a foreign object is stuck in the ear canal, you may (depending on the object) be able to remove the object at home. However, in this case, it would be wise to consult your doctor before attempting to remove the object—you do not want to unintentionally damage your ear. For other causes of hearing loss, you will need to see your doctor. If your hearing loss is caused by an infection, your doctor may need to prescribe antibiotics. If your hearing loss is caused by other conductive hearing problems, your doctor may refer you to a specialist to receive a hearing aid or a cochlear implant.

What Are the Complications of Hearing Loss?

Hearing loss has been shown to negatively impact a person’s quality of life and mental state. If you develop hearing loss, you may have difficulty understanding others. This can increase your anxiety level or cause depression. Treatment for hearing loss may improve your life significantly. It may restore self-confidence while also improving your ability to communicate with friends and family members.

How Can You Prevent Hearing Loss?

Not all cases of hearing loss can be prevented. However, there are several steps that you can take to protect your hearing:

• Use safety equipment if you work in areas with loud noises, and wear earplugs when you swim and go to concerts. Statistics from 2010 showed that 15 percent of individuals ages 20 to 69 experienced hearing loss due to loud noise (NIDCD).
• Have regular hearing tests if you work around loud noises, swim often, or go to concerts on a regular basis.
• Avoid prolonged exposure to loud noises and music.
• Avoid prolonged use of noisy surroundings like the industrial nose.
• Avoid exposure to high-frequency noises like engines, ammunition, and motorbikes.
• Avoid smoking as it hastens the hearing loss process.
• Seek help for ear infections, as they may cause permanent damage to the ear if left untreated.

Avoid the use of the following medicines which are ototoxic, please show this card to your family doctor when you go to him for treatment.

OTOTOXIC DRUGS

What Is Noise-Induced Hearing Loss /Acoustic Trauma?

Acoustic trauma is an injury to the inner ear that is often caused by exposure to a high decibel noise. This injury can be related to a single very loud noise or by exposure to a lower decibel noise over a long period of time. Some injuries to the head can cause acoustic trauma if the eardrum is ruptured, or if other injuries to the inner ear occur. The eardrum protects the middle and inner ear. It also transmits signals to the brain by way of small vibrations. Acoustic trauma can damage the way that these vibrations are handled, causing hearing loss. Sound moving into the inner ear can cause what doctors sometimes call a “threshold shift,” which can trigger hearing loss.

Types of Noise-Induced Hearing Loss.

If your doctor believes that your symptoms indicate acoustic trauma, he or she may try to differentiate between trauma that occurred through injury and trauma that occurred through exposure to loud noises. Different degrees of acoustic trauma can also require different treatments.

Who Is at High Risk for Noise-Induced Hearing Loss /Acoustic Trauma?

Those who experience the following types of situations are at a higher risk for acoustic trauma:

• those who work at a job where loud industrial equipment operates for long periods of time
• those who live or work where other high-decibel sounds continue for long periods of time
• individuals who frequently attend music concerts and other events with high-decibel music
• those who use gun ranges
• people who experience gun reports or other extremely loud sounds without proper equipment, such as earplugs

In terms of specific risks, those exposed to over 85 decibels of sound continually are at a higher risk for acoustic trauma. Your doctor may provide an estimate of the decibel range of normal daily sounds, such as an estimate of around 90 decibels for a small engine, in order to help you assess whether the sounds that you encounter put you at a higher risk for acoustic trauma and hearing loss.

Symptoms of Noise-Induced Hearing Loss /Acoustic Trauma

The main symptom of acoustic trauma is hearing loss. Experts point out that, in many cases, patients first begin to experience difficulty hearing high-frequency sounds. The trouble with sounds at lower frequencies may occur later. Doctors may test response to different frequencies of sound to assess the extent of acoustic trauma. One of the most important symptoms that can signal the onset of acoustic trauma is called tinnitus. Tinnitus is a type of injury to the ear that causes a buzzing or ringing sound. Those with slight to moderate tinnitus will most often be aware of this symptom when they are in a silent environment. While tinnitus can be caused by drug use, changes to blood vessels, or other factors, it is often a precursor to acoustic trauma when it is caused by exposure to loud noises. Tinnitus can be persistent or chronic, where long-term tinnitus is a good reason to suspect acoustic trauma.

Diagnosing Noise-Induced Hearing Loss /Acoustic Trauma

To diagnose acoustic trauma, your doctor will ask you what kind of noises you have been exposed to during different times of your life. Doctors may also use something called audiometry to detect signs of acoustic trauma. This kind of test involves providing sounds of various loudness and different tones in order to more carefully assess what the patient can and can’t hear.

Treating Noise-Induced Hearing Loss /Acoustic Trauma

Technical Hearing Assistance

While hearing loss can be treated, it cannot be cured. Your doctor may recommend technological assistance for your hearing loss condition, such as a hearing aid. New types of hearing aids called cochlear implants may also be available to help you deal with hearing loss from acoustic trauma.

Ear Protection

Your doctor will most likely recommend using earplugs and other kinds of hearing protection devices. These items, when applied to a workplace scenario, are part of the PPE (personal protective equipment) that employers should offer to workers.

Medications

In some cases, oral steroid medications may be prescribed to help with acoustic trauma. However, if you are experiencing hearing loss, your doctor will stress protection of the ear in order to prevent the problem from getting worse.

Prognosis for Noise-Induced Hearing Loss /Acoustic Trauma

Acoustic trauma and related hearing loss cannot be reversed. Some patients are able to keep the remaining portion of their hearing capacity by protecting their ears from loud noises. In some extreme cases, doctors will recommend learning sign language in order to allow for communications if hearing loss becomes considerable.

What Is Sudden Sensorineural Hearing Loss?

When you lose your hearing very quickly, it is called sudden sensorineural hearing loss (SSHL). It can happen instantly or over a span of several days, during which sound is gradually muffled or reduced. This type of hearing loss typically affects one ear. Decibels measure the intensity of the sounds we hear. Frequencies measure sound waves. Losing 30 decibels in three connected frequencies is considered SSHL. There are about 4,000 cases of SSHL every year in the United States, most commonly among people aged 30 to 60. Early treatment for SSHL can save your hearing. Most people recover, but about 15 percent have hearing loss that continues to worsen. Advances in hearing aid technology and cochlear implants are helping to improve communication for people affected by hearing loss. SSHL is a medical emergency and requires immediate attention.

Causes of SSHL

SSHL happens when the inner ear or the nerve pathways between the ear and the brain become damaged. Only about 10 to 15 percent of people with SSHL ever know what actually caused their hearing loss. That may be because there are more than 100 possible causes, including:

Congenital SSHL

Infants can be born with SSHL for a variety of reasons including:

• infections that pass from the mother (such as rubella, syphilis, and herpes)
• Toxoplasma gondii (a parasite that passes through the womb)
• individuals who frequently attend music concerts and other events with high-decibel music
• genetic factors
• low birth weight

Tests for Hearing Loss

Your doctor will take a medical history and conduct a physical exam. You will be asked about other medical conditions and about what over-the-counter and prescription medications you take. You may be asked to cover one ear at a time while listening to sounds at different volumes. Tests using a tuning fork can check if there is damage to the parts of the middle ear and eardrum that vibrate. Your hearing can be more thoroughly checked with audiometer tests. An audiologist can conduct thorough testing of your hearing ability using earphones. Different sounds and levels can be sent to each ear individually. A series of sounds at different volumes can help find the level where your hearing fades. Additional testing for a cause of a sudden sensorineural hearing loss should include an MRI (magnetic resonance imaging) scan looking for an acoustic neuroma (tumor of the nerve).

When to Test Your Child’s Hearing

Hearing loss could develop as a result of infections at birth, use of a ventilator, or certain medications known as ototoxic medications. It may not always be easy to know if your child is hearing correctly. You should have your child’s hearing tested if he or she:

• doesn’t seem to understand a language
• doesn’t attempt to form words
• has had many ear infections or problems with middle-ear fluid
• doesn’t seem to startle at sudden noises or respond to sounds as you would expect

Symptoms of SSHL

Hearing loss may be noticed upon awakening in the morning. Some people become aware of it when they use earphones or hold a phone to the deaf ear. Hearing loss is sometimes preceded by a loud popping sound.

Other signs include:

• trouble following group conversations
• muffled conversation sounds
• experiencing sounds that feel too loud
• inability to hear well when there’s a lot of background noise
• more trouble hearing women’s voices than men’s
• difficulty hearing high-pitched sounds
• experiencing dizziness or balance problems
• tinnitus (hearing ringing or buzzing sounds)

Hearing loss affects only one ear for nine out of 10 people with SSHL.

Treatment for SSHL

Early treatment may help your chances for a full recovery. However, the doctor will try to identify the cause of your hearing loss before treatment can begin. The most common treatment involves the use of steroids. Steroids can reduce inflammation and swelling. This may be especially helpful in patients who have diseases of the immune system. Hearing aids and telephone amplifiers can help if your hearing does not improve. Sign language and lip reading can improve communication for people with severe hearing loss. A cochlear implant can be surgically put in place. This implant doesn’t restore hearing to normal, but it can amplify sounds to a more normal level.

Outlook for SSHL

For some people, SSHL improves on its own without any medical intervention. Usually, this happens in the first few days after hearing loss. This is called a spontaneous recovery. Others recover their hearing more slowly, usually within a week or two. Fifteen percent of people who experience SSHL do not recover, but continue to lose their hearing in time.