We’ve covered the several different types of hearing loss in previous blogs—now, let’s take a deeper look at conductive hearing loss. Conductive hearing loss involves problems with the outer and middle ear, including such structures as the external ear (the part you can see), the ear canal, and the three miniscule bones of the middle ear, called the ossicles. To contrast, sensorineural hearing loss involves the inner ear and auditory nerves.
Causes of Conductive Hearing Loss: External Ear and Ear Canal
So what can cause conductive hearing loss? There are many different factors that can lead to a person having conductive hearing loss, and they occur in different areas of the ear. Common problems of the external ear and ear canal include:
- Earwax: Earwax is a leading cause of conductive hearing loss. Impacted earwax stuck in the ear canal can cause a serious loss of volume and may need to be treated by a doctor.
- Swimmer’s ear: Also known as otitis externa, swimmer’s ear commonly causes pain and ear tenderness, but severe swelling in the ear canal can cause hearing loss. That’s why it’s a good idea to wear waterproof earplugs if you’re prone to swimmer’s ear!
- Bony lesions: These benign growths on the walls of the ear canal cause the canal to narrow, and make it easier for wax and water to obstruct the ear. These can be managed with consistent cleaning and rarely require surgical removal.
- Malformations: Malformations of the ear structures are often genetic, and can lead to conductive hearing loss. Complete malformation of the ear canal is called atresia, is normally only on one ear, and is present at birth.
Causes of Conductive Hearing Loss: Middle Ear
Many cases of conductive hearing loss are due to problem in the middle ear—the eardrum and the ossicles. Middle ear causes of conductive hearing loss include:
- Fluid: Fluid that collects in the middle ear can lead to temporary conductive hearing loss, and is one of the most common causes of conductive hearing loss. Fluid can also be caused by Eustachian tube dysfunctions, and occurs often in children but can also affect adults.
- Ear infections: Infections of the middle ear, or otitis media, can also cause a buildup of fluid that results in conductive hearing loss. This is often seen in young children and if the infections are constant and long-lasting, can lead to permanent hearing loss.
- Ear drum collapse: Eustachian tube dysfunction can lead to excessive pressure against the ear drum, causing it to collapse and may require surgical intervention.
- Ear drum perforation: Infections or trauma can cause a hole to develop in the ear drum, leading to an incomplete capture of sound waves in the ear. Surgical reconstruction of the ear drum is an outpatient procedure with a 90% success rate.
- Trauma: Trauma to the ossicles, either from infections, head trauma, or ear drum collapse, can result in conductive hearing loss. Surgical reconstruction is used to repair the ossicles and restore hearing.
There are many causes of conductive hearing loss, and they can lead to temporary or permanent hearing loss depending on the source. An ear examination will determine the cause(s) of your conductive hearing loss and help you and your doctor identify treatment options for addressing hearing loss.