otometrics Madsen ZODIAC 901, Руководство пользователя

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hand side of the display (see Fig.4.6). If MEP can be calculated, the
pump pressure will now be set at that pressure.
Definitions of ECV,
MEP, SC, Grad, TW ECV is recorded at the start of the sweep, i.e. with the maximum pres-
sure when the sweep is in the negative direction, or the minimum pres-
sure when positive sweep has been selected using Setup. MEP is the
pump pressure at the peak of the tympanogram, i.e. when the pressures
on both surfaces of the eardrum are equal. The Gradient is calculated as
follows: static compliance minus the compliance where width = 100
daPa, divided by static compliance [SC – C (width=100daPa)
¸
SC. TW is
the pressure difference between the two points on the curve at which the
compliance is half the peak compliance.
Version 4.x Only The
MEP marker
appears automatically, and is located at the peak of the
sweep, i.e. at 0 daP. In cases where it is difficult to carry out a normal
sweep and obtain compliance data, e.g. with difficult or unsettled pa-
tients, you can manually move the marker in either direction by means
of
Softkeys 4 and 5 , and read out the computed values on the left of the
display. Note that an asterisk appears to the right of the MEP value if the
marker has been moved.
Air Release To restore the static pressure to zero quickly, press Air Release , which
automatically resets the pump position.
CAUTION! Where the patient is already experiencing pain or discomfort, caution
should be exercised in selecting pressure range and pump speed,
particularly in the positive pressure direction.
34 Operation Manual
MANUAL MODE Chap. 4 GN Otometrics
TYMPANOMETRY
4.1 ZODIAC 901 Middle-Ear Analyzer
Fig.4.5
Tymp. Sweep before
measurement
Fig.4.6
Tymp. Sweep after measurement