Full Digital Color Doppler Ultrasonic Diagnostic Instrument (Vet) User’s Manual V1.00
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6.5L64H1 probe variable frequency
range:4.5/5.5/6.5/7.5
7.5L40H1 probe variable frequency
range:6.0/6.5/7.5/9.0
6
Focus
Focus position
By default, color focus position
automatically locates in the vertical center of
color sampling box.
7
Linear color
steering
·Operate in CFM, PDI and PW mode;
·The function only be used with linear array
probe;
·Press the key to adjust the deflection
direction of color sampling box;
8
Velocity scale
3.5MHz probe
11 levels
6.5MHz probe
11 level
7.5MHz probe
11 levels
3.5MHz probe speed scale:
350Hz
～
7500Hz
6.5MHz probe speed scale:
350Hz
～
7500Hz
7.5MHz probe speed scale:
350Hz
～
7500Hz
9
Wall Filter
8-level, 50
～
350Hz
Filter out low-frequency echo signal not
generated by blood flow; so that the blood
flow signals that low echo intensity and high
velocity can pass.
10
Dynamic
Range
30
～
100
Selecting different dynamic range can
significantly change the display of image.
11
Harmonics
2-level
Switch the work frequency and harmonic
frequency.
12
Acoustic
Power
4-level
AP25, AP50, AP75, AP100
10.3.6 PDI mode
PDI (Power Doppler Imaging) mode, used to show the information of red blood cell density and
velocity in the flow for a certain period, and marks with the colors of different brightness, does not reflect the
information of flow direction.
Image’s parameter adjustment in PDI mode is the same as CFM mode.
10.3.7 PW mode
PW (Pulse-wave Doppler) mode, used to study the movement information of blood flow along a
scanning line in a certain region. The horizontal axis of PW spectrum diagram represents time, vertical axis
represents Doppler frequency shift. Under the circumstances of a known angle between sound beam and
blood flow, through the amplitude of frequency shift can calculate the blood flow’s velocity and flow, and
determine the information of laminar flow or turbulent flow in the blood flow.
To get a good spectrum to judge, the adjustment of spectral Doppler is particularly important. Please
carefully read and reference the following content before adjustment:
1). Sample volume. Spectral Doppler detects the frequency shift signal within the sample volume range to
evaluate the velocity of blood flow and its changes. The position of sample volume is usually placed on
the center of vessel. Flow velocity distribution within the vessel is not necessarily uniform. To obtain
more blood flow information, sample volume range should be set as wider as possible; the size is
equivalent to the detected internal lumen. But do not overlap with the vessel wall, doing thus to prevent
the reflective Doppler signal generated by vessel wall from interfering the blood flow detection results.
2). Angle correction. In the color Doppler examination, the smaller the angle between beam and flow is, the
better the display of color flow is, on the contrary, the angle is greater, the color flow signal is weaker. To
accurately measure the velocity of flow, the following steps for quantitative detection of blood flow
velocity are necessary: