Hprf - EDAN Acclarix LX4 User Manual

Acclarix LX4 Diagnostic Ultrasound System User Manual
Image Type
Steer
Frequency
Auto Trace
Auto Trace
Direction
Acoustic
power

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.
Spectral Doppler supports image presets for Low Flow, Medium
Flow and High Flow.
This control is only available for linear transducers and steers the
Doppler cursor angle left or right.
This determines the Doppler transmit frequency used for
imaging.
Press to activate the Auto Trace function on a real-time or frozen
PW Doppler strip.
The Auto Trace function automatically traces the spectral
Doppler waveform and records several measurements on
selected waveforms. See section 7.3.1 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.
Table 5-3 PW Mode Touch Screen Controls
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Imaging