User guide
ELI
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ECH001XN111-A4 – 07/2022
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Introduction and test setup
3.7 Audiometry
3.7
Audiometry
Audiometry
is the basic review of hearing. This test allows a quick check of hearing, from the transmission chain to
the brain. The measure is obtained through the emission of a calibrated frequency sound wave, of which we will lower
the level until the patient can't hear it anymore. The sounds are emitted by a supra-aural headphone, in one ear then in the
other.
Pure-tone Audiometry
allows hearing thresholds screening for each ear in a frequency range from 125Hz to 8 kHz with
regular headset and up to 16KHz with high frequency headset. Bone conduction evaluates performance of the inner ear
and the auditory nerve, air conduction tests all of the acoustic function from the external ear to the auditory nerve.
The interpretation of the resulting audiogram allows to know the degree of hearing loss and the kind of deafness.
Pure tone audiometry also allows to find a discomfort threshold, or also the research for any tinnitus frequency.
Speech audiometry
is a further investigation of the pure-tone audiometry. It does not determines a threshold of percep-
tion, but a threshold of intelligibility of language, or discernment of phonemes. The test consist of making the patient
repeat a series of words he hears. By varying the power of diction of the words, a curve relating the percentage of dis-
crimination in relation to the power is obtained. Well known by hearing aid specialist to fine tune the settings of hearing
aids, it is also used to diagnosis retrocochlear pathologies like neuropathy or acoustic neuromas.
3.7.1
Equipment
To make a
Audiometry
measurement you need the following equipment:
Common elements for all configurations
ELI
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unit
Air conduction audiometry
1 audiometric headset or the insert earphone
Bone conduction audiometry
B71 bone vibrator
2 foam ear tips ER3-14A 13mm
or
2 foam ear tips ER3-14B 10mm
