Acclarix AX8/Acclarix AX7 Diagnostic Ultrasound System User Manual Imaging
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Table 5-3 PW Mode Touch Screen Controls
5.3.3. HPRF
Conventional PW Doppler scales are limited by the Nyquist limit. High Pulse Repetition Frequency
(HPRF) allows the system to exceed the Nyquist limit by having multiple Doppler pulses in the body at
the same time. In HPRF imaging, multiple Doppler gates are displayed since the multiple Doppler
pulses could be giving information from different depths. HPRF is automatically invoked when needed
to maintain the requested depth and scale. For example, if the system is at a high scale and you move
the cursor deeper, the system may automatically invoke HPRF. This can also happen if the cursor is
deep and you increase scale.
If HPRF is active, you will see multiple Doppler gates on the reference image. If you do not want to be
in HPRF, decrease the scale or move the primary PW gate to a shallower location until only one gate
is displayed.
5.4 CW Mode
5.4.1. Using CW Mode
CW mode is only available on phased array transducer.
1. Perform the image scanning to get a good image in B mode or B+Color(DPI/DPDI) mode;
2. Press <
D
> on the console to display sample line;
3. Press
CW
key on the touch screen to switch to CW mode;
4. Use the trackpad and touch controls to adjust the position of the sample line;
5. Press <
D
> or <
Update
> on the console to enter B+CW or B+Color(PDI/DPDI)+CW mode and
display Doppler strip.
6. Adjust image parameters to optimize the Doppler strip.
7. When spectrum is displayed, pressing <
Update
> toggles between acquiring the Doppler strip and
acquiring the reference image.
In CW mode, pressing on <
PW
> on the touch screen will switch to PW mode directly.
5.4.2. CW Image Optimization
The following touch controls can be used to optimize the CW image.
Auto
Optimization
The Auto push button automatically updates the PW gain, DR,
baseline and PRF scale. Each single press of the button
renews the automatic optimization.
Whether Gain, DR or Scale/Baseline is optimized when
pressing Auto button can be configured in Set-up. See section
11.1.4 for detail.