Clinical Application Of The Ac440 Tests; Air Conduction Audiometry - Interacoustics Affinity 2.0 Additional Information

1.7 Clinical application of the AC440 tests

This section will give a short introduction to the clinical applications of the AC440 module. The methods
described here primarily based on the textbooks by Stach (1998) and Katz (2002) and describes one way of
perf orming the individual tests. Other standards may, however, dictate other procedures.

Air conduction audiometry

In air conduction audiometry, a test signal is presented to the test subject via headphones or insert phones.
The test subject responds to the signal by pressing a patient response button. The audiometric threshold is
def ined as the lowest intensity at which the patient can detect the test signal 50% of the time
The purpose of air-conduction audiometry is to establish the hearing sensitivity at various f requencies. The
test provides inf ormation about the conductive and sensory systems of hearing but cannot distinguish
between conductive and sensorineural hearing losses.
Required items:
• The Af f inity 2.0 hardware
Licensed AC440 Audiometry module within your Af f inity
•
• Headphones or insert phones
A response button
•
Test procedure:
1) Open the Af f inity Suite through your patient management system, Noah or OtoAccess®.
2) Ensure you are in the AUD module of the Suite and if needed select a test protocol in the List of
Protocols.
3) Perf orm otoscopy to make sure that any anatomical abnormalities are considered and that cerumen is
not obstructing the ear canal. Perf orm a medical history to f ind out whether there are any conf ounding
f actors which may prevent you f rom perf orming the test or make considerations f or. It is also good to
ask if the patient is experiencing tinnitus. If yes, you may consider doing the test using warble tones or
narrow band noise instead of pure tones which can be hard to distinguish f rom the tinnitus at some
f requencies.
4) Select the input and output f or channel 1.
If masking is needed, use the channel 2 to determine masking level and f requency. Note that this
decision is usually made af ter perf orming an unmasked audiogram based on dif f erences in thresholds.
Channel 2 should be muted or switched of f in the beginning of the evaluation. If pref erred, Auto
Masking or Masking Help can be turned on.
D-0004576-Q – 2022/05
Affinity/Equinox2.0 – Additional Information
2.0 hardware
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