What are the main types of hearing loss?

Conductive hearing loss occurs when sound waves do not reach the inner ear because of a blockage in the outer or middle ear. This is typically caused by wax build-up, fluid in the middle ear or problems with the eardrum itself.

Sensorineural hearing loss occurs when sound waves cannot be converted into electrical signals by either the cochlea (inner ear) or auditory nerve. This type of hearing loss is much more common than conductive hearing loss, especially in adults over age 65. Sensorineural hearing loss can be caused by many things, including noise exposure (e.g., working in a factory), aging and genetic factors.

Mixed hearing loss is usually a combination of conductive and sensorineural hearing loss — for example, when there is both a blockage in the outer or middle ear and damage to structures within the inner ear.

What is hearing loss?

Hearing loss is a common symptom of aging. Hearing loss can also be caused by exposure to loud noise, medical conditions, or injury to the ear.

Hearing loss is the result of damage to the nerve pathways from the inner ear to the brain. This type of hearing loss may not be permanent and can often improve on its own without treatment.

If you have had a significant hearing loss for at least 3 months, you may have sensorineural hearing loss. Sensorineural hearing loss is also called nerve deafness, which means that it affects your inner ear and/or the nerve pathways between your inner ear and your brain.

Sensorineural hearing loss can be caused by:

• Age-related changes in your ear (presbycusis)
• Genetic factors (hereditary)
• Trauma or other injuries to your head or neck
• Autoimmune disorders such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and vasculitis

Sensorineural hearing loss

Sensorineural hearing loss is the most common type of permanent hearing loss. It’s also called sensorineural deafness or nerve deafness.

Sensorineural hearing loss occurs when part of the inner ear or auditory nerve becomes damaged by aging, noise exposure or certain drugs. This type of hearing loss can’t be reversed, but there are many things you can do to improve your quality of life and independence.

Symptoms of sensorineural hearing loss

If you have sensorineural hearing loss, you may have trouble understanding speech. You may also notice that:

• Certain sounds seem muffled or unclear (this is called distortion)
• Noises are louder than they should be (called hyperacusis)
• Sound seems to come from one side of your head more than the other

Causes

The following are some possible causes of sensorineural hearing loss:

– Exposure to loud noises (e.g., factory noise, music)

– Head injury (e.g., blow to the head)

– Ototoxic drugs (drugs that damage the inner ear)

Treatment

Sensorineural hearing loss can be treated with one or more of the following:

Hearing aids: Hearing aids amplify sound and help people hear better in difficult listening situations. They work by boosting sounds in specific frequencies, making them louder than others. Hearing aids are useful for people with mild to moderate hearing losses.

Cochlear implant: A cochlear implant is a small electronic device that sends signals to your brain, bypassing damaged hair cells in the inner ear. The implant consists of an external piece that’s worn behind your ear and a small internal piece that’s surgically placed inside the head behind the ear.

Auditory brainstem implant: An auditory brainstem implant may be used when all other treatments have failed, but it’s still experimental at this point (2018). This device bypasses damaged inner ear hair cells, sending signals directly from a microphone in your outer ear to electrodes implanted inside your brain stem — bypassing any possible damage to these cells and allowing you to hear again.

Conductive hearing loss

Conductive hearing loss occurs when the bones of the ear are not properly aligned, so sound waves are unable to travel from the outer ear to the inner ear. This type of hearing loss often affects babies and toddlers. In most cases, conductive hearing loss can be treated with a simple procedure called a myringotomy and tympanostomy tube insertion (also known as “myringoplasty”).

Causes

Conductive hearing loss is usually caused by fluid or mucus buildup in your eardrum (tympanic membrane). Fluid can build up due to an infection or injury to your ear canal. Mucus may build up if you have allergies or sinus problems. Fluid or mucus buildup can also cause a perforation in your eardrum — which allows air into your middle ear, causing it to become infected.

Symptoms of Conductive Hearing Loss

The signs and symptoms of conductive hearing loss include:

• Ear pain or pressure;
• Difficulty understanding speech;
• Trouble understanding high frequencies such as s, sh, f and v

Treatment

Conductive hearing loss can be treated by improving the transmission of sound through the outer and middle ear. This may be achieved by correcting the underlying cause, or by inserting a hearing aid.

Treatment of conductive hearing loss may involve:

• Re-routing any fluid that is causing a blockage
• Cleaning out any foreign bodies in the ear canal (this may require flushing with water)
• Applying medication to reduce inflammation and swelling

Mixed hearing loss

Mixed hearing loss is a term that is used to describe a combination of sensorineural and conductive hearing losses. This type of hearing loss occurs when there is damage to both outer hair cells and the auditory nerve.

In some cases, mixed hearing loss can be caused by an underlying condition such as otosclerosis or Ménière’s disease. However, this is not always the case.

Causes

Mixed hearing loss has many possible causes, including:

Age-related hearing loss – As we age, our ears are less able to detect high-pitched sounds. This can lead to a decrease in speech discrimination and difficulty with understanding speech in noisy environments.

Genetic predisposition – Some people are born with genes that make them more susceptible to certain types of hearing loss than others. For example, someone who has family members with sensorineural hearing loss may be at risk for developing it themselves. In other cases, genetic predisposition may cause conductive hearing loss instead (or vice versa).

Symptoms

The symptoms of mixed hearing loss are very similar to those of sensorineural hearing loss. You may have a hard time hearing certain frequencies, have difficulty understanding speech, or have trouble distinguishing between similar sounds.

The most common symptom of mixed hearing loss is difficulty understanding speech in a noisy environment. This can be frustrating and embarrassing, but if you’re not sure that your hearing loss is mixed, it’s important to talk with your doctor before making any changes to your lifestyle.

While it’s possible that you could have both types of hearing loss at the same time, most people only have one type at a time. If you notice that your ability to hear high-pitched sounds has changed more than your ability to hear low-pitched sounds, then you probably have mixed hearing loss.

Treatment

Compression therapy. Using a special device, a doctor can put pressure on the ear canal to help block out background noise. Compression therapy is recommended for patients with moderate to severe mixed hearing loss.

Antibiotics. If your doctor thinks that an infection is causing your mixed hearing loss, he or she may recommend antibiotics. Antibiotics can be used either alone or with other medications, depending on the cause of your condition.

Medications. Your doctor may prescribe certain medications to treat the underlying cause of your condition. For example, if you have fluid in your middle ear from an infection, he or she may prescribe an antibiotic to fight the infection and reduce fluid buildup in the inner ear.

Single-sided deafness

Single-sided deafness is a condition in which one ear has lost its hearing. This can occur for many reasons, such as injury or infection. In some cases, it may be caused by an underlying medical condition such as an ear tumor, diabetes or multiple sclerosis.

Single-sided deafness can affect both hearing and balance. In some instances, people with single-sided deafness may have difficulty performing daily activities because they do not hear noises coming from one side of their body.

Causes of Single-sided Deafness

There are many possible causes of single-sided deafness, including:

• Injury to the ear canal or eardrum (perforation)
• Infection in the ear canal or middle ear
• Tumors in the inner ear or brainstem (vestibular schwannomas)