GE Vivid i, Руководство пользователя

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Scanning Modes
Vivid i User’s Manual
91
2378958-100 Rev. 02
Color-Mode Soft menu controls
Tissue priority
Emphasize either the color of the color mode or the greyscale
tissue detail of the 2D image. Tissue priority is available in both
Live and Freeze.
Sample volume
Adjusts the size of the color flow Doppler sampling area. Lower
setting gives better flow resolution while a higher setting
increases sensitivity and helps to locate turbulent flows.
Frequency
Enables the adjustment of the transmission frequency to
control the sensitivity or the level of penetration. The selected
frequency is displayed in the status window. Adjusting
Frequency may affect Sample Volume and LVR settings.
Lateral Averaging (Color 2D only)
Smooths the image by averaging collected data along the
same horizontal line. An increase of the lateral averaging will
reduce noise, but this will also reduce the lateral resolution.
Radial Averaging
Use Averaging con-
trols with caution so
as not to obscure
significant diagnos-
tic information
Smooths the image by averaging collected data along the
same radial line. An increase of the radial averaging will reduce
noise, but this will also reduce the radial resolution.
Power
When power is re-
duced, it reduces
the signal-to-noise
ratio, so that the im-
age may become
noisier.
Controls the amount of acoustic power applied in all modes.
When power is set to maximum, it is equal to or less than the
maximum acoustic power permitted by the FDA. The Thermal
Index (TI) and the Mechanical Index (MI) are displayed on the
screen.
Trackball controls
ROI (Region Of Interest) size
When the trackball command Size is selected (see also
"Trackball operation" on page 54), the height and width of the
color area (or ROI) is adjusted from the trackball.