GE Logiq 500, Руководство пользователя

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Doppler
LOGIQ 500 Basic Users Manual
2233658–100 Rev. 0
5–59

PW Doppler Mode Sub-Menu Page 2
Color
Tag
MID
Preset PWD
Tag
Positn
Color Penet. Sweep
Speed
Set Up ECG
Figure 5–24. PW Doppler Mode Sub-Menu Page 2
Sweep Speed Penetration (Penet.)
Description Changes the speed at which the timeline is
updated. (Also found in the CWD soft
menu.)
NOTE: Time or distance measurements
are not allowed across sweep speed
changes.
Penetration can be increased by lowering
the operating frequency of the active
probe.
For reference, Doppler frequencies (with
penetration On or Off) are shown according
to probe in Table 5–7 on
5–44.
Benefits Speed up or slow down the spectrum for
analysis to record more or fewer
occurrences over time. Allows for a slight increase in penetration
without changing gain or acoustic output.
Values Slow (16 sec), Mid (8 sec), Fast (4 sec)
and Very-Fast (2sec).
Very-Fast is a function in Doppler mode
only.
Pre-processing function.
On or Off.
Pre-processing function.
Affects on
Other Controls If more cardiac cycles are seen, the
spectrum appears smaller; if less are
seen, the spectrum appears larger or more
spread out. Acoustic output, gain and TGC may be
able to be reduced due to increased
penetration.
Bioeffects
Decreasing the probe transmitting
frequency, without decreasing acoustic
output, tends to increase Mechanical and
Th
l I d l H i d Thermal Index values. However, improved
penetration should allow for decreasing
patient exposure time.