Having any degree of hearing loss that interferes with communication, development, learning or interpersonal interactions.

Type of Hearing loss:

1. Conducting hearing loss

  • When sound waves are blocked to reach inner ear because of external and middle ear disorder.

  • Obstruction of external and middle ear may be due to dry wax, foreign bodies and tumors.
  • Thickening and perforation of ear drum.
  • Otosclerosis (immobility of joint between stapes and oval window due to bone overgrowth or otitis media).
2. Sensorineural hearing loss or nerve deafness

  • Hearing loss caused by permanent or temporary damage to the sensory cells or nerve fibers of the inner ear.
  • It results from damage of any structure in cochlea (such as hair cell, organ of Corti, basilar membrane and cochlear duct) or disease of nerve pathway ear and cerebral cortex

  • Degeneration of hair cell and VIII cranial nerve (vestibulocochlear nerve) due to some antibiotic like streptomycin and gentamicin.
  • Damage of cochlea due to prolonged exposure to loud noise more than 85dB.
  • Myxedema, DM, trauma, surgery and infection
  • Meniere's Syndrome or endolymphatic hydrops - Excessive endolymph fluid called meniere's syndrome, which cause tinnitus, vertigo and hearing loss.
  • Presbycusis (presby means old) - Atrophy of ganglion cell (group of nerve cell bodies) in cochlea & loss of elasticity of basilar membrane, occur mainly old age. 

        Test uses for hearing impairment are audiometry test and Tuning fork tests.

Audiometry test:

  • It is use to measures hearing acuity.
  • The nature and severity of auditory defect could be determined by the techniques called audiometry.
  • The instrument used is called audiometer.
  • Audiometer is capable of generating sound waves of different frequency from lowest to highest.
  • At a particular frequency, if the patient hears the sound with than 30 dB above zero level, the person said to have hearing loss of 30 dB.
Tuning fork tests:

  • Tuning fork test used to differentiate, conductive or sensorineural hearing loss.
  • These are two types e.g. Weber's tuning fork test (test for unilateral deafness) and Rinne's tuning fork test (it use to compare bone conduction hearing with air conduction).

  • Advice to use hearing aid (an electroacoustical device that amplifies sounds).
  • Face the patient when speaking to facilitate the communication.
  • Talk to person in normal volume and lower pitch because shouting is not helpful and higher frequency are less easily heard.
  • Advice to avoid exposure to loud noise.
  • Cochlear implantation in sensory neural hearing loss.
  • Management of Meniere's disease in acute attacks are bed rest, antihistamines, vasodilators (e.g. nicotinic acid), sedatives, discontinuation of smoking avoid watching T.V, low-salt diet (less than 2 g/day) and diuretics.


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