EDAN DUS 60 User Manual page 24

DUS 60 Digital Ultrasonic Diagnostic Imaging System User Manual
4B mode Imaging Control
Press this key to enter the 4B mode. The system divides the image area into four quadrants: the
first quadrant is on the top left, the second on the top right, the third on the bottom left, and the
fourth on the bottom right.
Press it repeatedly to active one of the four images. The probe direction of the activated image is
brighter than the direction of the frozen images. The four images are obtained separately and only
one image at a time is displayed in real time.
B/M mode Display Control
Press it to enter the B/M mode, the B mode and the M mode images are displayed on the screen
at the same time (Abbreviated as B/M or B+M). There is a line constituted by points with regular
spacing on B mode image, which is called the M Mark. Roll the trackball to move the M Mark.
Press Set to locate the M Mark.
M mode Display Control
Press this key to enter the M mode. It displays an M mode sweep. The slope of this mode has four
levels.
Pulsed-Wave Doppler mode Display Control
Press this key to switch between the B mode the B+PW mode.
A pulsed-wave Doppler (PW) scan produces a series of pulses used to study the motion of blood
flow in a small region along a desired scan line, called the sample volume.
The X-axis of the graph represents time, and the Y-axis represents Doppler frequency shift. The
shift in frequency between successive ultrasound pulses, caused mainly by moving red blood
cells, can be converted into velocity and flow if an appropriate angle between the insonating
beam and blood flow is known.
Shades of gray in the spectral display represent the strength of the signal. The thickness of the
spectral signal is indicative of laminar or turbulent flow (laminar flow typically shows a narrow
band of blood flow information).
Pulsed-Wave Doppler mode and B mode are shown together in a mixed mode display. This
combination lets you monitor the exact location of the sample volume on the B image in the B
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DUS 60 Digital Ultrasonic Diagnostic Imaging System User Manual
Image Display window, while acquiring Pulsed-Wave Doppler data in the Time Series window.
Operation:
In the B scan, the long line lets you adjust the sample line position, the two parallel lines (that
look like =) let you adjust the sample volume (SV) size and depth, and the line that crosses them
lets you adjust the correction angle (PW angle).
Figure 5-5 Example PW Scan
In PW mode, you can choose scanning in B mode or PW mode by pressing Update. When you
are scanning in non-simultaneous mode either the B or the time series window receives data. This
lets you independently change the PW PRF. When scanning in simultaneous mode, both the 2D
and the time series window receive data. This feature lets you define which method is used, based
on the exam type.
The sample volume indicator allows you to start a scan in a B scan mode, set the sample volume,
and switch to Doppler mode. The sample volume locks in position.
1. Press PW to enter B mode and adjust all image control settings appropriate for the current
exam.
2. Place the cursor inside the vessel of interest.
3. You can now adjust the sample line, SV size, or correction angle as needed for the scan: move
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