Hprf; Update; Cw-Mode; Cw Touch Screen Controls - EDAN Acclarix AX4 User Manual

Acclarix AX4 Diagnostic Ultrasound System User Manual
Auto Trace
Direction
Acoustic
power
Auto
Optimization

5.2.2. 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.

5.2.3. Update

The Update hard key toggles between acquiring the Doppler strip and acquiring the reference
image.

5.3 CW-mode

CW may be available on the phased array transducer. There are two ways to invoke CW:
 Press the CW button on the Doppler touchscreen to switch between PW and CW modes.
 Configure the F1 or F2 programmable hardkey to invoke CW directly (see section 9.1 for
details).

5.3.1. CW Touch Screen Controls

The following touchscreen controls impact the CW image. The location of the touchscreen
controls can be customized (see section 3.8 for details).
Press one of the three options to specify which side of the
Doppler baseline to take measurements from:
Up: traces positive portion of waveform (above baseline).
Down: traces negative portion of waveform (below baseline).
Both: traces waveform on both sides of baseline.
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.
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 9.1.4 for
detail.
Table 5-3 PW Mode Touch Screen Controls
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Imaging