EDAN Acclarix AX15, User Manual

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Acclarix AX3 Series 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 < CW > on the console to display sample line;
3. Use the trackball and touch controls to adjust the position of the sample line;
4. Press < CW > on the console to enter B+CW or
B+Color(PDI/DPDI)+CW mode and
display
Doppler strip.
5. Adjust image parameters to optimize the Doppler strip.
6. 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 console will switch PW mode directly.
Acoustic
Power Adjusts the acoustic output power of the activated transducer.
It is only available in live imaging. Higher acoustic power
numbers correspond to increased sensitivity in the Doppler
display and improved penetration, but the ALARA principle
should be followed in actual clinical situations.