GE Vscan Air, Руководство пользователя

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Scanning
Vscan Air
–
User Manual
5-27
Direction GP092020-1EN Rev 18
Color steer
Slant the ROI (Region of Interest) of the Color Flow linear image
left or right to get more information without moving the Vscan Air
CL probe.
Use the controls on the center top and bottom to steer the angle.
NOTE: Color steer applies only when using the linear array transducer
of the Vscan Air CL.
Color Aliasing
If the blood flow velocity exceeds the Nyquist limit indicated by
the number displayed with the velocity bar aliasing may occur.
Aliasing appears as a shift in color from the color representing
positive velocity to color representing negative velocity or visa
versa.
Positive velocity indicates flow towards the transducer and
negative indicating flow away from the transducer.
The maximum velocity or Nyquist limit is displayed on top of the
velocity bar.
Fast and slow flow (High and low velocity scale)
For a few presets, there is a control available in the color flow
mode for alternating between high and low velocity scales. A
higher velocity scale is needed to avoid aliasing while imaging of
faster (arterial) flow. A lower velocity scale optimizes the
imaging of slow flow (venous).
The presets that support selection between high and low
velocity scale are following:
CAUTION
When blood flow velocity exceeds the max velocity range
covered by the device, color aliasing may occur, which results
in incorrect velocity estimates.
Curved array Linear array
Abdominal Vascular
OB-Gyn MSK
Vascular Small Parts
Cardiac