GE Logiq 500, Руководство пользователя

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Adding Color
LOGIQ 500 Basic Users Manual
2233658–100 Rev. 0
5–42
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Power Doppler Imaging (option)
Power Doppler Imaging (option)
Description Power Doppler Imaging, also known as PDI, (option) is a color flow mapping technique
used to map the strength of the Doppler signal rather than the frequency shift or velocity
of the signal. PDI is a different way of processing the power information from the color
flow transmissions by using different color maps and not displaying directional
information. Using this technique, the system plots color based on the number of
reflectors that are moving, regardless of velocity.
Accessing/
Changing While scanning in the CFM Mode, enable the Blue Shift key (key will be lighted) and
press P.
NOTE: For USA systems, the User Define Key 6 has been locked and programmed to
toggle the PDI mode on/off. User Define Key 6 can be reprogrammed for other
functions if it is unlocked.
Although remaining in the CFM Mode Top Menu, the system will shift to the PDI presets
and color maps.
Values Only power maps are available in the PDI mode.
P1 thru P4 are non-topo (power) maps.
P5 and P6 are Directional PDI Maps (option).
P7 and P8 are topo maps.
Changes between non-topo and topo maps can only be done in real-time, not on a
frozen image.
Affects on
Other Controls Only changes between P1 thru P4, P5 and P6, or P7 and P8 are post-processing
functions and do not affect image acquisition controls. PDI parameters need to be
changed in real-time. Some controls that affect CFM also affect PDI.
Hints
Optimizing the
PDI Option Custom Display pages 8 and 16 have parameters specific to PDI.
The PDI Velocity choice is a trade-off between low flow detectability and wall motion.
The PDI B High Resolution choice is a trade-off between frame rate and color
resolution.
The PDI B Frame Average choice is a trade-off between a sharper noisy appearance or
a smoother less noisy appearance to the image.
The activation of the Persistence function will override any previous selections made for
PDI B Frame Average. When Persistence is deactivated PDI B Frame Average will
return to normal operation.
The PDI B Wall Filter choice is made depending on the frequency of the probe.
NOTE: Remember that parameters found on Custom Display page 8 are probe
dependent. Set up these parameters for all probes that will be used for PDI.
NOTE: Parameters on Custom Display page 16 are effective for all probes.