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.
Sensitivity
Select the sensitivity of the envelope curve
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.
6.3.2 Extended View (XTD-View)
XTD-View provides the ability to construct and view a static 2D image which is wider than the
field of view of a given transducer. This feature allows for viewing and measurement of
anatomy that is larger than a regular screen.
XTD-View constructs an extended image from individual image frames as the operator slides
the transducer along the surface of the skin. The probe is oriented parallel to the direction of
motion throughout the scan. The quality of the result is user-dependent and requires some
additional skills and practice to develop proper technique and become fully proficient.
Examples include scanning of vascular structures and connective tissue in the arms and legs.
Note
on page 2-13 before using this feature.
Figure 6-9 XTD-View. Scan Mode and Read Mode
Using XTD-View
1.
Touch
2D
on the user interface to start B-Mode.
2.
Optimize the B-Mode image.
2D Mode
Voluson™ SWIFT / Voluson SWIFT+ Instructions For Use
5831612-100 Revision 4
6-17
Содержание Voluson Swift
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