Types of Hearing Loss
Hearing loss is caused by damage to one or more parts of the hearing system. The type of hearing loss depends on where the damage occurred. There are three types of hearing loss: 1) conductive; 2) sensorineural, and 3) mixed.
Conductive hearing loss occurs when there is damage or disease in the outer or middle ear. This includes the ear, ear canal, eardrum, or bones in the middle ear. Conductive hearing loss can sometimes be corrected with surgery or medication. When surgery of medication are not helpful, the hearing loss can often be improved with hearing aids.
Conductive hearing loss can be caused by:
- Fluid in the middle ear
- Damage to the middle ear bones
- Damage to the eardrum
- Ear wax
- Birth defects
Sensorineural hearing loss occurs when there is damage to the inner ear (cochlea) or the hearing nerve. This is sometimes referred to as nerve deafness, but the medical term is sensorineural hearing loss. Sensorineural hearing loss is usually permanent and cannot be corrected. Hearing aids and other assistive hearing technologies can often help this type of hearing loss.
Sensorineural hearing loss can be caused by:
- Natural aging process
- Exposure to loud noise
- Medications that are toxic to the ears
- Traumatic injury
Mixed hearing loss is a combination of both conductive and sensorineural hearing loss. Therefore, both the outer or middle ear and the inner ear are damaged.
A comprehensive hearing evaluation is necessary to differentiate between types of hearing loss and appropriate treatment options. For more information on the evaluation procedure, please see the Basic Hearing Test section under the Hearing Evaluation tab.