There are many different scenarios that can lead to hearing loss, such as exposure to loud noise, wax buildup in the ear canal, ear infection, fluid behind the eardrum, and age related hearing loss. Less common reasons for hearing loss include exposure to certain medications, sudden sensorineural hearing loss, and congenital ear malformations. In this blog post, we will outline some of the more common causes of hearing loss. Early detection of hearing loss is often key to optimizing treatment and improving outcomes.
Onset of hearing loss can be slow and insidious or sudden and acute. Below are some common signs and symptoms of hearing loss:
Difficulty hearing conversation in a loud environment, such as a restaurant
Need to turn up the volume louder than usual
Difference in sound in one ear versus the other
Tinnitus or ringing in the ear
Evaluation of your hearing loss begins with a thorough history and a comprehensive ear, nose and throat exam. We may then proceed to hearing testing for more information.
Auditory or hearing tests help determine the type and degree of hearing loss you may have. Several tests may be performed including tympanometry and acoustic reflex, air conduction audiometry and otoacoustic emissions. There are also additional hearing tests which can be performed by an audiologist.
In addition to hearing tests, sometimes we may also obtain an MRI or CT scan to gain more information and rule out other conditions that may be influencing your hearing loss.
There are two main types of hearing loss: conductive and sensorineural. You may also have mixed hearing loss, which is a combination of conductive and sensorineural hearing loss.
Conductive hearing loss is defined as hearing loss resulting from physical or mechanical dysfunction of the outer or middle ear. This dysfunction prevents sound from being properly transmitted to your inner ear. Below are some common causes of conductive hearing loss.
Middle ear fluid/ effusion
Fluid can accumulate in the middle ear space, resulting in hearing loss. This can happen during an acute ear infection or acute otitis media. Another cause for this to happen is dysfunction of the eustachian tube. Eustachian tube dysfunction (ETD) can happen as a result of a sinus infection or a recent plane flight. Patients with chronic nasal issues, such as allergic rhinitis, may also develop ETD. Treatment usually begins with medications to help reduce inflammation in the nose. An in-office procedure to drain the fluid may be necessary in some patients.
Otosclerosis involves the fixation of the stapes bone. This loss of movement reduces conduction of sound to the inner ear, resulting in a conductive hearing loss. There may also be tinnitus associated with this type of hearing loss. Patients may choose to proceed with surgery to replace the stapes bone to restore hearing. Hearing aids are also an option for patients who wish to avoid surgery.
A cholesteatoma is an abnormal skin growth in the middle ear space. Cholesteatomas are non-cancerous but can enlarge and damage middle ear structures, such as ossicles, resulting in subsequent hearing loss. Cholesteatomas can result from chronic ear infections or damage to the eardrum. Definitive treatment is surgical removal of the cholesteatoma with reconstruction of the middle ear bones as needed.
Sensorineural hearing loss is defined as dysfunction of the inner ear and/or associated nerves. Below are some of the most common causes of sensorineural hearing loss.
Age-related hearing loss (Presbycusis)
Age-related hearing loss, or presbycusis, is the most common type of sensorineural hearing loss. This type of hearing loss is usually found equally in both ears and results in the loss of high frequency sounds first. Hearing loss is gradual and progressive. The ear exam in patients with presbycusis is usually normal. Diagnosis is confirmed by history and audiologic testing. Depending on the degree of hearing loss, some patients may wish to pursue hearing aids, while others are comfortable with their level of hearing and may not require them.
Types of hearing aids
There are several types of hearing aids available depending on the type of hearing loss you have and patient preference. You will be evaluated by an audiologist to determine the type and size of hearing aid most appropriate. Behind the ear (BTE) hearing aids sit on top of or behind the ear. In the ear (ITE) hearing aids are custom fitted and worn inside the ear. Completely in canal (CIC) hearing aids are even smaller than ITEs and sit completely in the ear, making them barely visible to others. Bone anchored hearing aids (BAHA) are surgically implanted hearing aids that use the bone behind the ear to conduct sound to the inner ear. BAHA may also be used for unilateral hearing loss to conduct sound from the hearing impaired ear to the other ear. Cochlear implants are surgically implanted hearing aids involving a sounds processor worn behind the ear that transmits sounds to the surgically implanted device in the cochlea which transmits sound to the nerve.
Congenital hearing loss
Sensorineural hearing loss can be congenital- present from birth. Congenital hearing loss may be due to a genetically inherited condition or issues during pregnancy. With the advent of neonatal hearing screening, this type of hearing loss is usually discovered soon after birth. Further testing is needed to determine optimal treatment. It is important for children to to be evaluated as soon as possible, so that they may be fitted with hearing aids as needed.
Noise-induced hearing loss
Noise-induced hearing loss (NIHL) is one of the most common reasons for hearing loss. This type of hearing loss can be temporary or permanent. NIHL causes hearing loss through the damage of inner ear hair cells. According to the CDC, more than half of people in the US from ages 15-35 are at risk of noise induced hearing loss and 12% of children ages 6-19 have some degree of permanent hearing loss from loud volume on personal devices such as phones, iPads or laptops. It is important to always assess the volume of your headphones and get into the habit of turning the volume down to the lowest point at which you can still hear. Try to avoid listening with headphones for long periods of time.
Environmental exposure to loud noises can also cause noise-induced hearing loss. If you have been in the military, work in construction, or frequent loud concerts, you may have been exposed to noise at damaging levels. You should try to avoid noise that exceeds 85 decibels (db). Normal conversation is usually around 60 decibels. Louder noises can exceed 85 decibels. Some examples include loud traffic at around 85 db, a personal music device with a maximum volume around 105 db, concerts around 110-120 db, emergency sirens at approximately 125 db and firearms/fireworks at around 150 db.
Noise-induced hearing loss is a preventable hearing loss. Awareness and active protection of your ears can help you avoid hearing loss. If loud noises are unavoidable, be sure to wear protective headphones or earplugs to prevent damage to your hearing. If hearing loss is permanent hearing aids may be considered. The following picture shows the decibel level of normal sounds you may encounter in your everyday environment.
Sudden hearing loss
Sudden hearing loss is an acute onset of unilateral hearing loss. This hearing loss is usually quite dramatic, as it occurs without any warning. For example, someone may note an immediate loss of hearing in one ear while engaged in an activity such as watching television. Less commonly, hearing loss may be more subtle with it occurring progressively over the course of 24-72 hours. This type of hearing loss has many potential etiologies (or causes) that may not be easily identified. Swift evaluation and medical intervention is imperative in ensuring the best possible recovery of hearing. Treatment should begin as soon as hearing loss is noted. Treatment often begins with a course of oral steroids. Intratympanic steroids, the injection of steroids into the middle ear space, may be considered in certain cases. Imaging with an MRI of the middle ear will also be considered.
If you are experiencing hearing loss, we will help you to determine the root cause of your issue and discuss the best possible treatment options that are right for you and your lifestyle.