Types of Hearing Loss
Hearing loss is classified by what region of the auditory system is damaged. There are three types of hearing loss: conductive hearing loss, sensorineural hearing loss and mixed hearing loss
Conductive Hearing Loss
This occurs when sound is not conducted sufficiently through the outer ear auditory canal to the eardrum and the tiny bones, also called ossicles, of the middle ear. Conductive hearing loss generally involves a decrease in sound level, or the ability to hear faint sounds. Often this type of hearing loss can be medically or surgically corrected.
Examples of circumstances that may inflict conductive hearing loss include:
- Conditions associated with middle ear pathology such as fluid in the middle ear from colds, allergies, reduced eustachian tube function, ear infection, ruptured eardrum, benign tumors
- Impacted earwax (cerumen)
- Infection in the ear canal (external otitis)
- Presence of a foreign object
- Deformity or absence of the outer ear, ear canal, or middle ear
- Numerous outer and middle ear problems can be treated with medication or surgery. Should these not assist in improving one’s hearing, hearing aids can be used
Sensorineural Hearing Loss
Sensorineural hearing loss occurs when the inner ear (cochlea) or the nerve pathways from the inner ear to the brain are damaged. There is no way to medically or surgically correct sensorineural loss as it is considered a permanent decrease in the ability to hear especially faint sounds. It also affects the ability to deduce or interpret particular sounds.
Sensorineural hearing loss can be caused by diseases, drugs that can harm the auditory system, and genetic disorders. It can also be caused by intense noises, aging, and traumatic injury.
Mixed Hearing Loss
If conductive hearing loss occurs simultaneously with sensorineural hearing loss, it is considered a mixed hearing loss. In other words, there may be damage in the outer or middle ear and in the inner ear (cochlea) or auditory nerve. This damage cannot be reversed medically; however, well-fitted hearing aids can improve the quality of one’s hearing.
