Welch Allyn MicroTymp 3 portable tympanometric instrument - User Manual - Manual (Page 43)

Directions for use Printing 226-Hz results 43
Data section
The data section displays numeric values for the four key characteristics of the
tympanogram:
• Static Admittance (Peak Ya) is a calculated measure of the compensated static
acoustic admittance (height) of the tympanometric peak reported in acoustic
millimhos (mmho). Given appropriate normative values, static admittance (Peak Ya) is
a useful indicator of middle ear disease.
• Tympanometric Gradient (GR) is a measure of the width of the tympanogram
reported in decapascals (daPa) at 50% of static admittance (Peak Ya) or the
tympanometric peak. Given appropriate normative values, tympanometric gradient is
a good indicator of the presence of middle ear effusion.
• Tympanometric Peak Pressure (TPP) is the location of the tympanometric peak on
the pressure axis. TPP is reported in decapascals (daPa). TPP indicates if there is
pressure behind the eardrum but usually does not indicate middle ear disease.
• Equivalent Ear Canal Volume (+200 Vea) is an estimate of the volume of air in front
of the probe, measured in cubic centimeters (cc). A high volume suggests an eardrum
perforation or patent tympanostomy tube. Perforations can be present when Vea is
normal.
If the numeric values are greater or less than the 90th percentile of the normative data for
a child or an adult, an asterisk appears under the C(hild) or A(dult) column. The normative
data are listed in the table on
page 32 .
For the following tympanometric results, no data will be printed:
• 1000-Hz results
• Peak Ya is greater than 1.5 mmho. The message "High Peak Ya" will appear at the top
of the tympanogram.
• Peak Ya less than 0.3 mmho.
• Peak Ya which is incomplete; for example, a negative pressure tympanogram which is
so far negative that the peak has not been reached and data are incomplete.
• Tympanogram has too much artifact. Artifact is generally caused by movement of the
subject or the instrument.
Interpretive messages section
The interpretive messages section of the printout provides an interpretive, verbal
description of the tympanometric result.
The computer in the Printer/Charger examines the data for clinically-significant deviations
from the normal values. For example, a tympanogram which is too wide may be indicative
of a developing or resolving otitis media; the message reads "Tympanogram Is Wide.”
The hierarchy of messages displayed is as follows:
Noisy Tympanogram
Low Peak Height, Small Ear Volume
Low Peak Height, Normal Ear Volume