SonoSite M-Turbo, Руководство по обслуживанию

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Chapter 5: Performance Testing 35
Axial Measurement Accuracy
Note: Measurements must be performed while the image is frozen.
Lateral Measurement Accuracy
Penetration
Set Up Axial
Measurement
Accuracy 1 Acquire the image.
2 Press the Freeze key.
3 Press the Caliper key. The caliper appears on the image display. (See the M-Turbo Ultrasound
System User Guide , if necessary, for caliper operation.)
4 Use the touchpad to position one of the calipers.
5 Press the Select key to fix the caliper and enable the other caliper.
6 Use the touchpad to move the other caliper. The results update as you move the caliper, and
the measurement is complete when you finish moving the calipers. (Press the
Select key to
alternate the active caliper, and adjust the measurement with the touchpad.)
Test Axial
Measurement
Accuracy 1 Measure the distance, center to center, of any two pins that are 5-12 cm apart vertically.
2 Verify that the distance measured is within the tolerance listed in Table 5.1 .
Set Up Lateral
Measurement
Accuracy Perform “Set Up Axial Measurement Accuracy” on page 35 .
Test Lateral
Measurement
Accuracy 1 Measure the distance, center to center, of any two pins that are 4-10 cm apart horizontally.
2 Verify that the distance measured is within the tolerance listed in Table 5.1 .
3 Press the Freeze key to return the system to live 2D mode.
Table 5.1: System Measurement Accuracy
Measurements Tolerance
Axial Distance +/- 2%
Lateral Distance +/- 2%
Caution: A referenced .7db/cm phantom is required for performing penetration measurements
Test
Penetration 1 Adjust the system controls to obtain a clear image that shows the limits of echo penetration
as shown in
Table 5.2 .
2 Set the system exam type and optimization mode settings to the values shown in Table 5.2 .
3 Measure from the center of the skinline to the deepest vertical position—where the scatter
echoes start to break up and tissue definition is lost.
4 When making penetration measurements on a phantom, apply the phantom reference
value and tolerance to the measurement.
5 Press the Freeze key and then save the image. Press the Freeze key again to return to live
imaging.