User guide

Chapter 4: Measurements and Calculations 45
Measurements
4 Press the SELECT key.
5 Using the touchpad, complete the trace, and
press the
SET key.
See “To save a measurement to a calculation
and patient report” on page 43.
M Mode measurements
The basic measurements that you can perform in
M Mode imaging are as follows:
• Distance in cm/Time in seconds
• Heart Rate (HR) in beats per minute (bpm)
The time scale above the trace has small marks at
200 ms intervals and large marks at one-second
intervals.
To measure distance (M Mode)
You can perform up to four distance measurements
on an image.
1 On a frozen M Mode trace, press the
CALIPER
key.
A single caliper appears.
2 Using the touchpad, position the caliper.
3 Press the
SELECT key to display the second
caliper.
4 Using the touchpad, position the second caliper.
See “To save a measurement to a calculation
and patient report” on page 43.
To measure heart rate (M Mode)
1 On a frozen M Mode trace, press the CALIPER
key.
2 Select HR on-screen.
A vertical caliper appears.
3 Using the touchpad, position the vertical caliper
at the peak of the heartbeat.
4 Press the
SELECT key.
A second vertical caliper appears.
5 Using the touchpad, position the second vertical
caliper at the peak of the next heartbeat.
See “To save a measurement to a calculation
and patient report” on page 43. Saving the heart
rate measurement to the patient report overwrites
any heart rate entered on the patient information
form.
See also “To measure fetal heart rate (M
Mode)” on page 67.
Doppler measurements
The basic measurements that you can perform in
Doppler imaging are Velocity (cm/s), Pressure
Gradient, Elapsed Time, +/x Ratio, Resistive
Index (RI), and Acceleration. You can also trace
manually or automatically.
For Doppler measurements, the Doppler scale must
be set to cm/s. See “Presets setup” on page 22.
To measure Velocity (cm/s) and Pressure
Gradient (Doppler)
1 On a frozen Doppler spectral trace, press the
CALIPER key.
A single caliper appears.
2 Using the touchpad, position the caliper to a
peak velocity waveform.
This measurement involves a single caliper from the
baseline.
See “To save a measurement to a calculation
and patient report” on page 43.
To measure Velocities, Elapsed Time, +/x
Ratio, Resistive Index (RI), and
Acceleration (Doppler)
1 On a frozen Doppler spectral trace, press the
CALIPER key.
A single caliper appears.
2 Using the touchpad, position the caliper to a
peak systolic waveform.