Reflex Latency Test Screen (Extended License); Eustachian Tube Function - Non-Perforated Eardrum - Interacoustics AA222 Instructions For Use Manual

AA222 Instructions for Use – US

3.6.7 Reflex latency test screen (extended license)

The reflex latency test will be automatically performed with an activator intensity of 10 dB above the reflex
threshold. The test will show a pop up and ask for the intensity of the activator in cases where:
•
within the same protocol, the reflex threshold cannot be found
•
the required intensity is at or above the warning level as set up in the protocol settings
•
the required intensity is above the maximum intensity that the transducer allows to be played for this
particular activator
The default display of the reflex latency test, shows the graphs of the latency measurements which are
measured on the selected ear. The following information is found in the display:
A The first 300ms of the tympanometry curve.
B The table with measurement values which are only calculated if the measurement could be
completed.
•
Level, stimulus level
•
Pressure, the pressure at which the decay reflex is measured. Usually the Decay test will
be set up to use the peak pressure of a preceding tympanogram.
•
Stimulus, stimulus frequency
•
Latency Value, the latency value is the time interval between onset of the stimulus and the
point where 10% of the reflex deflection value is reached. The reflex deflection value is
measured as the average of the deflection between 250 and 300ms after stimulus onset.
3.6.8 Eustachian tube function – Non-perforated eardrum
The display of the Eustachian tube function test for the non-perforated eardrum shows graphs for the
selected ear in which the three tympanograms of the adapted Williams procedure are plotted. The Williams
procedure keeps the pressure in between the first and second tympanogram at stop pressure, and between
the second and third tympanogram at the start pressure. In between all tympanograms the original Williams
procedure is to ask the patient to swallow. In order to get a bigger displacement of tympanograms, we advise
asking the patient to perform a Valsalva's maneuver after the first tympanogram and to swallow after the
second tympanogram.
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