Understanding the way in which we hear is the initial step in understanding the many causes of hearing loss and the unique types of hearing loss. Sound enters via the outer ear, which is the portion of the ear on the exterior of the head, but also includes the eardrum and the ear canal. The eardrum can also be considered part of the middle ear, an area which also includes the 3 tiny bones called ossicles that take the vibrations of sound and transmit them to the inner ear. The inner ear has three key parts – the cochlea, the two semi-circular canals (important for balance) and the acoustic nerves which transmit the sound signals to the brain. This is an incredibly intricate mechanism, and problems can arise in any part of it that produce hearing loss. There are 4 main classifications of hearing loss.
Conductive hearing loss is caused by something interfering with the transmission of sound through the outer or middle ear. Conductive hearing loss is often curable using medication or with surgery, and if neither is effective, it is treatable using hearing aids.
Sensorineural hearing loss generally refers to damage to the hair cells of the inner ear, to the cochlea, or sometimes to the acoustic nerves. Sensorineural hearing loss can usually not be treated using medication or surgery, but its effects can be minimized using hearing aids to allow the person to hear more normally.
Suffering from both conductive and sensorineural hearing loss is called mixed hearing loss and is generally treated with a combination of medication, surgery, and hearing aids.
Damage to the inner ear or auditory nerves preventing a message from being understood by our brain that entered the ear normally, is called central hearing loss.
Each of these four main classifications contain several sub-categories, such as the degree of hearing loss, which can be mid-level, moderate, severe, or profound. Additional sub-categories include whether the hearing loss occurs in one ear or both ears (unilateral vs. bilateral), whether it occurs at the same degree in both ears (symmetrical vs. asymmetrical), and whether the hearing loss happened before or after the person learned to speak (pre-lingual vs post-lingual). Hearing loss can also be categorized as having occurred slowly or gradually (progressive vs. sudden), whether the degree of loss changes and gets better at times or stays the same (fluctuating vs. stable), and whether the loss was present at birth or developed later in life (congenital vs. acquired). The most important thing to bear in mind, however, is that whatever type of hearing loss you may have incurred, our specialists can help you to diagnose and treat it properly.