Deafness and hearing loss can be caused by damage to the auditory nerve or inner ear. This type of hearing loss is called sensorineural hearing loss. Another type of hearing loss is called conductive hearing loss. What causes conductive hearing loss?
Unlike sensorineural hearing loss, people with conductive hearing loss may have auditory nerves and cochleae or inner ears that function normally. With conductive hearing loss, the sound cannot reach the cochlea. A blockage or middle ear abnormalities may be blocking sound from the inner ear.
A common cause of conductive hearing loss in children is inner ear infections. During the infection, fluid may build up in the middle ear. There may also be swelling of the ear canal. These changes in the ear due to the infection could cause sound to be muffled.
Usually, normal hearing returns when the infection subsides. If a child has recurrent ear infections or infections that are not responding well to noninvasive treatment, the doctor may recommend the surgical implantation of tubes in the ears to help the infections clear and avoid damage to the ear from infection.
Glue ear is another condition that causes fluid accumulation in the middle ear. The fluid may be thick and therefore cause a significant hearing impairment until medically treated to remove the trapped fluid. In some cases, swimmer’s ear causes conductive hearing loss. Swimmer’s ear is the irritation of the lining of the ear canal that can lead to significant inflammation and swelling.
Causes of conductive hearing loss include damage to the eardrum. An eardrum, or tympanic membrane, can rupture due to auditory trauma such as exposure to drastic changes in air pressure as someone may experience if the person is in close proximity of an explosion. The eardrum could also become perforated from an injury or an ear infection.
Otosclerosis is a condition that causes the tiny bones of the middle ear to become rigid. The middle ear contains small bones that vibrate to pass sound from the outer ear to the cochlea. If these bones lose their ability to vibrate sufficiently, sounds are not able to reach the inner ear. Damage to the small bones of the middle ear from an injury could also cause conductive hearing loss.
Some of these causes of conductive hearing loss are medically treatable. Conductive hearing loss can be caused by a buildup of earwax in the ear canal. In those cases, the removal of the earwax by a medical professional or the use of an earwax removal kit is likely to restore normal hearing.