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Chapter 4 Diagnosis Modes
Tips!
Things to Consider for Real Time Automatic Doppler Trace
1. Aliasing occurs because PRF is too low in comparison to the image speed, or the spectrum is clustered
around the baseline because PRF is too high.
2. Peak is indistinctive or intermittent such as in Spectral waveforms for veins.
3. Meaningful spectrum distinction becomes difficult because Doppler Gain is set too high or too low.
4. An index is displayed during the transition time after Sample Volume is moved with the Trackball.
5. The major spectral signals are cut off because Doppler Wall Filter is set too high.
6. Peak Trace is interrupted due to abnormal Doppler noise or artifact, and the heart rate is above
approximately 140 bpm.
The trace and/or results of Real Time Automatic Doppler Trace may not be accurate in the above
situations. Furthermore, during auto calculation, results will not be displayed if the Freeze function is
run against inaccurate values.
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AutoCalc Direction
Use the Soft Menu dial-button [3]. You can select the part of spectrum to use AutoCalc from Up, Down,
or All.
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Simultaneous
Each time you press the Soft Menu dial-button [4], the Simultaneous function turns on and o.
NOTE:
It appears in the PW menu only when “Utility > Setup > General > Simultaneous Mode” is set
to Allow.
If the Simultaneous function is enabled, you can view the 2D image and Spectral Doppler image
simultaneously in real time. If it is disabled, you can view only one of the two images.
The Simultaneous function decreases Doppler PRF, thus decreasing the measurable speed range.
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Mean Trace
NOTE:
When AutoCalc is on, Mean Trace is displayed in the Soft Menu.
Displays a mean value by performing Doppler Trace. Press the Soft Menu dial-button [5] to turn it on or
o.
I want to learn how to do angle correction on PW Doppler on my machine.
How do I assess PW angle cursor?
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