There are different types and varying degrees of hearing loss.
It can be partial or total, sudden or gradual, temporary or
permanent, and it can affect one ear or both. While some people
lose their hearing for a very short period of time as a result
of an accident, medical illness or treatment, for others it is a
progressive process that takes many years. Some illnesses, such
as diabetes, hypertension, or Meniere's disease, can contribute
to the progressive loss of hearing. Hearing loss is classified
according to which part of the auditory, or hearing system, is
affected. The outer ear consists of the visible ear and ear
canal. The middle ear is an air-filled cavity containing three
small bones. The middle ear is separated from the ear canal by
the eardrum. There are three main types of hearing loss:
Permanent hearing loss occurs when inner ear nerves become
damaged and do not properly transmit their signals to the brain.
Those who suffer from this condition may complain that people
seem to mumble or that the