ECR Table Patterns of Hearing Loss Flashcards
What is the pathophsyiology of conductive loss
External or middle ear disorder impairs sound condution to inner ear
what are causes of Conductive hearing loss?
- foreign body
2, otitis media (inflammation of middle ear) - perforated eardrum
- otosclerosis of ossicles (abnormal growth of bone near middle ear)
usual age of onset of conductive loss
childhood and young adulthood, up to age 40
ear canal and drum of conductive loss
abnormality usually visible, except in otosclerosis
Effects of Conductive Loss
Little Effect on sound
Hearing seems to improve in noisy environment
Voice becomes soft b/c inner ear and cochlear nerve are intact
Is hearing better or worse in noisy environment with Conductive hearing loss
Better!
What is Weber TEst in Conductive hearing loss (in unilateral hearin loss)
Tuning fork at vertexlo
louder in IMPAIRED Ear
Sound lateralizes to IMPAIRED EAR- room noise not well heard, so detection of vibration IMPROVES
What are results of RINNE test in Conductive hearing
Tuning fork at external auditory meatus then on mastoid boine
Bone conduction longer than or equal to air conduction (BC>AC)
Louder in BONE!
while air conduciton through external or middle ear is impaired, vibrations through bone bypass problem to reach cochlea
What is pathophysiology of sensorineural loss?
Inner ear disorder involves cochlear nerve and neuronal impulse transmission to brain
What are causes of Sensorineural loss?
Loud noise exposure, inner ear infections, trauma, tremors, congenital and familial disorders, and aging
Usual age of onset of sensoineural loss
Middle or later years
Ear canal and drum of sensorineural
problem not vidisble
Effects of sensorineural loss
Higher regsiters are lost, so sound may be distorted
hearing worsens in noisy environment
Voice may be loud b/c hearing is difficult
How can you tell it is Sensorineural loss in Weber teest?
Sound lateralizes to GOOD EAR - inner ear or cochlear nerve damage impairs transmission to affected ear
What are results of Rinne test with sensorieural test
AIR> BOne
Air conduction longer than bone conduciton A
AC>BC
inner ear or cochlear nerve is less able to transmit impulses regarless of how the vibration reach cochlea.
