Conductive hearing loss
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decrease in sound transmission through the external and middle ears
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a conductive hearing loss decreases air transmission but not bone transmission
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as discussed under middle ear acoustic impedance, the frequency range affected is determined by whether the conduction block is increasing the mass (high frequencies) or the stiffness (low freqencies) properties or both (as shown in this example)
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it can be detected using Rinne test, as well as seen in the audiogram (as shown in this example; click here for more info re. audiogram interpretation)
common causes of a conductive hearing loss include:
- ruptured eardrum
- intra-tympanic fluid (usually due to otitis media)
- otosclerosis