Any problem in the outer or middle ear that prevents sound from being conducted properly is known as a conductive hearing loss. Conductive hearing losses are usually mild or moderate in degree, ranging from 25 to 65 decibels.
In some cases, a conductive hearing loss can be temporary. Depending on the specific cause of the problem, medication or surgery can help. A conductive hearing loss may also be helped with hearing aids or a middle ear implant.
Sensorineural hearing loss results from missing or damaged sensory cells (hair cells) in the cochlea and is usually permanent. Also known as “nerve deafness”, sensorineural hearing loss can be mild, moderate, severe or profound.
Mild to severe sensorineural hearing loss can often be helped with hearing aids or a middle ear implant.* Cochlear implants are often a solution for severe or profound hearing loss.
Some individuals have a sensorineural hearing loss only in the high frequencies, also referred to as partial deafness. In these cases, only the hair cells at the base of the cochlea are damaged. In the inner part of the cochlea, the apex, the hair cells which are responsible for processing the low tones are still intact. Combined electric and acoustic stimulation, or EAS**, was developed specifically for these cases.
A mixed hearing loss is a combination of a sensorineural and conductive hearing loss. It results from problems in both the inner and outer or middle ear. Treatment options may include medication, surgery, hearing aids or a middle ear hearing implant.
A problem that results from the absence of or damage to the auditory nerve can cause a neural hearing loss. Neural hearing loss is usually profound and permanent.
Hearing aids and cochlear implants cannot help because the nerve is not able to pass on sound information to the brain.
In many cases, an Auditory Brainstem Implant (ABI)*** may be a therapeutic option.
* The Vibrant Soundbridge is approved for the treatment of conductive and mixed hearing losses as well as for implantation in children from the age of 10 and above in Canada.
** The EAS indication is not approved in Canada.
*** The Auditory Brainsteam Implant is not approved in Canada.