Type and Degree of Hearing Loss
The ear is divided into three parts: an external ear, a middle ear and an inner ear. Each part performs an important function in the process of hearing.
The external ear consists of the auricle (pinna) and ear canal. These structures gather the sound and direct it down the ear canal, towards the eardrum membrane.
The middle ear chamber lies between the external and the inner ear and consists of an eardrum membrane and three small ear bones (ossicles): malleus (hammer), incus (anvil) and stapes (stirrup). These structures transmit the sound vibration to the inner ear. In doing so they act as a transformer, converting the sound vibrations in the external ear canal into fluid waves in the inner ear.
The inner ear chamber contains the microscopic hearing and balance nerve endings (hair cells) bathed in fluid. Fluid waves initiated by movement of the stapes bone stimulate the delicate hearing nerve endings, which in turn transmit an electric impulse to the brain where it is interpreted as sound.
Types of Hearing Impairment
A complete audiologic/otologic examination by a competent ear specialist is necessary to determine the type of hearing impairment and severity as well as its probable cause and appropriate treatment.
The treatment of choice may be remedial, preventive, medical, surgical or a combination of these. Each person with impaired hearing should have the benefit of adequate auditory rehabilitation.
A well rounded program of rehabilitation for persons with a hearing loss may include speech reading, auditory training, speech strategy techniques, instruction in the use of a hearing aid and guidance in social adjustment. All aspects of the program do not necessarily apply to each individual with impairment, but each individual may be helped through some of these methods.