Hearing Loss

Disease affecting the external and/or middle ear produce a CONDUCTIVE hearing loss: Disease affecting the cochlear and auditory nerves produce a SENSORINEURAL LossHearing normally develops during the first half dozen years of life. If the brain does not receive appropriate stimulation during this time it does not have the subsequent capabilities of hearing. This occurs in congenital or pre-lingual deafness.

Depending on which section of the ear that is affected, two main types of hearing loss can be identified.

  • Any problem in the outer or middle ear that prevents the ear from conducting sound properly is known as a conductive hearing loss. Conductive hearing losses are usually mild or moderate in nature and in some cases can be temporary. In many cases, medication, surgery or hearing aids can help.
  • A problem in the cochlea caused by missing or damaged sensory cells (inner hair cells) can cause sensorineural hearing loss. This type of hearing loss is usually permanent and can be classed as mild, moderate, severe or profound. Severe or profound hearing loss can usually be helped with a cochlear implant. However, in rare cases when the auditory nerve itself is damged a cochlear implant would be unsuitable. In such cases a brain stem implant could be considered.

There are many causes of sensorineural hearing loss. The common principle is that the delicate inner ear hair cells become so damaged that they are unable to respond and transmit any meaningful signals to the auditory cortex that there is effectively no useable hearing.

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