Full Digital Color Doppler Ultrasonic Diagnostic Instrument (Vet) User’s Manual V1.00
- 24 -
the smaller sampling depth is. The display area of two-dimensional image and color flow sampling
ranges also has an impact on the frame rate. If the real-time in the examination is poor, you can improve
frame rate by the following methods:
A. Narrow the scanning width (linear) or angle (convex array, sector scan) of two-dimensional image,
reducing the display area of two-dimensional image.
B. Narrow the color sampling box, reducing the display area of blood flow.
C. Improve the PRF. But this method reduces the detection sensitivity of low blood flow and decreases
sampling depth, you should pay attention to use.
D. If the color Doppler flow map and spectrum Doppler are simultaneously dynamically displayed, you
can freeze one of them.
1. CFM mode operation
Press
key to enter CFM mode.
2. Sampling box position
By default, move the trackball to adjust the position of CFM sampling box on the image;
3. Sampling box size
Press
『
Set
』
key, the right lower corner of sampling box image shows a small mark “x”, that means
moving the trackball to start adjusting the size of sampling box. At this time, move the trackball, the size
of sampling box will be accordingly changed. Press
『
Set
』
key again to exit the adjustment of sampling
box size, and return to moving the position of sampling box. Such repeated operations, can realize the
adjustment of CFM sampling box.
4. Display adjustable parameters in CFM mode
For CFM images, in the “Parameters” menu user can adjust “D Freq”, “PRF”, “Wall Filter”,
“Sensitivity”, “Persistence”, “Threshold”, “Balance”, “Color Smooth”, “Artifact Remove”, “Dyn Range”,
“Edge”, “Comp Curve”, “IP”, “Frame Avg” and “Image Opt”; in the “Display” menu user can adjust “V
Reverse”, “H Reverse”; or respectively turn
,
,
knob to adjust PRF, wall filter,
dynamic range; turn
knob to adjust the gain of color image.
Parameters adjustment table in CFM/PDI mode
No. Items
Parameters
Value/Status
Descriptions
Remark
Dopper
Frequency
3.5MHz probe 2
levels
6.5MHz probe 2
level
7.5MHz probe 2
levels
3.5MHz probe CFM frequency:
2.5MHz, 3.3 MHz
6.5MHz probe CFM frequency:
5.0MHz, 5.7MHz
7.5MHz probe CFM frequency:
5.0MHz, 6.5MHz
PRF
11-level, 350
～
7500Hz
Adjusting velocity range acturally adjusts
the PRF. Velocity range is set too high, the
blood flow is not satisfied, particularly
difficult to detect low-velocity blood flow;
be set too low, it will occur color aliasing.
Velocity range should be adjusted to
maximize the display of low-velocity blood
flow, but not to appear color inversion.
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.
1
“Parame
ters”
menu
Sensitivity
6-level, 0
～
5
Reduce noise; increase the sensitivity of
blood flow.