Sensitivity
Select the sensitivity of the envelope curve (only available when RT Trace is active).
Note
It is possible to switch between Sensitivity and Volume by pressing the control.
Baseline
Baseline can be used to prevent aliasing in one flow direction similar to the PW
Doppler baseline shift. Shifting the baseline enlarges the velocity range in one
direction. The zero line of the color bar is also shifted.
WMF
The Wall motion filter eliminates vessel wall motion noise that is low in velocity but
high in intensity. Use a wall filter that is high enough to remove motion artifacts, but
that is sensitive enough to display low velocity flows in small vessels.
PRF
The Pulse Repetition Frequency (PRF) has direct influence on the velocity range.
The higher the Pulse Repetition Frequency the lower the velocity range. As the
display scale increases, the maximum Doppler shift information that can be
displayed without aliasing also increases. Aliasing is where the blood velocity
exceeds the maximum measurable velocity, causing the displayed flow within the
vessel to portray flow in the wrong direction. The disadvantage of using a higher
PRF is a loss of sensitivity to low flow velocities.
Flow Presets
select between 3 different buttons
UtA, UmA and MCA. Only one button can be
active at the same time. With pressing the button again it will be deactivated. Use
Flow Presets for optimizing vessel flow representation scanning.
6.3 2D Mode options
The options described in this chapter are not available in all countries or need specific
upgrades.
Note
Read all safety precautions before using this system.
6.3.1 Continuous Wave Doppler (CW-Doppler)
CW Doppler imaging includes a spectral analysis which describes the Doppler shift signal from
the moving reflectors within the CW cursor line. The spectral display scrolls from left to right
and depicts the spectral distribution of the components of the Doppler shift frequency over
time. Frequency or velocity values appear on the vertical axis and time along the horizontal
axis. Component amplitudes appear as shades of gray. The brighter the shade, the higher the
amplitude.
2D Mode
Voluson™ SWIFT / Voluson SWIFT+ Instructions For Use
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Содержание Voluson Swift
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