5-20 Image Optimization
5.6 PW/CW Doppler Mode
PW (Pulsed Wave Doppler) mode or CW (Continuous Wave Doppler) mode is used to provide
blood flow velocity and direction utilizing a real-time spectrum display. The horizontal axis
represents time, while the vertical axis represents Doppler frequency shift.
PW mode provides a function for examining flow at one specific site for its velocity, direction and
features. CW mode proves to be much more sensitive to high-velocity flow display. Thus, a
combination of both modes will contribute to a much more accurate analysis.
CW imaging is an option.
5.6.1 Basic Procedures for PW/CW Mode Exam
1. Select a high-quality image during B mode or B + Color (Power) mode scanning, and adjust to
position the area of interest in the center of the image.
2. Tap [PW]/[CW] on the right side of the operating panel to enter PW/CW sampling line
adjustment status.
The sampling status will be displayed in the image parameter area in the top-left corner of the
screen as follows:
PW Sampling Line
Adjustment
CW Sampling Line
Adjustment
3. Set the position of the sample line by dragging the sampling line; drag the SV gate to place the
SV on the target.
4. Adjust the angle and SV size according to the actual situation: drag the PW angle line to
change the angle, pinch on the image area to adjust SV size.
5. Tap [PW]/[CW]/[Update] or double-click the sampling line to enter PW/CW mode and perform
the examination. You can also adjust the SV size, angle and depth in real-time scanning.
6. Adjust the image parameters during PW/CW mode scanning to obtain optimized images.
Tap [Image] to open the image menu. Adjust the parameters to optimize the image.
7. Perform other operations (e.g., measurement and calculation) if necessary.
Tap [Update] to switch between B (B+Color) and PW image.