
Full Digital Color Doppler Ultrasonic Diagnostic Instrument (Vet) User’s Manual V1.00
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Chapter Sixteen PW mode measurement and calculation
16.1 PW mode measurements
Press
key, and then press
【
Update
】
key to enter PW spectrum mode, freeze the image,
press
key, it can measure the following measurements, as figures:
Fig. Measurement menu in PW mode
The measurement method for heart rate and time in PW mode is the same as M mode measurenment.
The below describes the other measurement items in PW mode.
16.1.1 Velocity measurement
Function: measures the velocity and pressure gradient on a certain point on the Doppler spectral
waveform on the PW mode image.
Pressure gradient formula:
2
0004
.
0
V
P
∗
=
∆
mmHg, where V unit is cm/s.
Measure method:
1. Move the cursor to
〖
Velocity
〗
menu item in
【
PW Meas
】
menu, press
『
Set
』
key to enter measurement
status;
2. Operate the trackball or the direction keys to move the cursor to the measured point, press
『
Set
』
key,
the velocity and pressure gradient will be shown on right side of the display area;
3. Repeat step 2 to start a new velocity measurement.
16.1.2 Acceleration measurement
Function: measures the velocities of two points and their time interval on the PW spectral image, and
calculate the maximum velocity and acceleration.
Measure method:
1. Move the cursor to
〖
Acceleration
〗
menu item in
【
PW Meas
】
menu, press
『
Set
』
key to enter
measurement status;
2. Operate the trackball or the direction keys to move the cursor to the first point to be measured for
velocity, press
『
Set
』
key to fix the point;
3. Operate the trackball or the direction keys to move the cursor to the second point, the right display
area shows the measured value in real-time, press
『
Set
』
key to finish this measurement;
4. Repeat steps 2 and 3 to start a new acceleration measurement.
16.1.3 Pulsatility Index measurement
Function: On the blood flow waveform of PW spectrum image, select the maximum velocity and