Hearing Disorders

Causes

Causes of Hearing Loss

Age: Aging is the most common cause of hearing loss.

Disease: Meningitis, Meniere's syndrome, benign growths, and tumors on the hearing nerve can cause hearing loss, as can viral infections such as mumps and measles.

Drugs: Some drugs and antibiotics can cause damage to hair cells in the inner ear and the auditory nerve. Some of these drugs include, but are not limited too, quinine, aminoglycosides, diuretics and large doses of aspirin.

Infections: Otitis media is a middle-ear infection characterized by the formation of fluid in the middle ear. This can be caused by allergies, head colds, inflamed tonsils and adenoids, blocked eustachian tubes, sore throats and viruses.

Malformation: A misshapen ear canal can sometimes cause a hearing loss.

Noise: Noise exposure (hunting, factory/plant noise, engine noise) can cause permanent hearing loss.

Perforation: Perforation of the eardrum can be caused by a change in air pressure associated with flying or scuba diving, a foreign object such as a cotton swab used to clean the ears, or pressure caused by a middle-ear infection.

Wax: Wax can build up in the ear canal, stopping sound from passing through the ear canal. A physician, nurse or audiologist can periodically remove the ear wax. (Cotton swabs or sharp objects should never be used to clean the ears because they can push the wax deeper into the ear and may puncture the eardrum).

Types of Hearing Loss

Sensory hearing loss occurs when the inner ear is damaged. The most common causes are aging, inner-ear infection and noise exposure. Sensory hearing loss is usually not medically or surgically treatable. Most people with a sensory hearing loss find that hearing aids are beneficial.

Neural hearing loss occurs when the hearing nerve or the nervous system is damaged. The inner ear generates neural impulses that travel through the hearing nerve to the brain. Aging can cause degeneration of the hearing nerves. Hearing aids may help. Another cause is a tumor, such as an acoustic neuroma, that presses on the hearing nerve.

Conductive hearing loss occurs when the outer or middle ear fails to work properly. Sounds become "blocked" and are not carried to the inner ear. Conductive hearing losses are often treatable with medicine or surgery. Common causes are fluid behind the eardrum or wax buildup in the ear canal.

Conductive hearing loss also can occur when the eardrum or bones of the middle ear are disrupted. Normally, when fluid builds up, it drains through the eustachian tube, which opens to the throat. The eustachian tube is normally opened by swallowing, yawning and chewing. An inflammation of the tube may keep it closed, causing fluid to build up in the middle ear. Often the result of an upper respiratory infection, the inflammation can usually be corrected.