Service manual

62 Chapter 8: Performance Testing
Penetration
The penetration measurement is an integral part of the quality assurance program. Penetration is defined as the
deepest depth at which an ultrasound system can provide adequate image quality of small anatomical structures.
Penetration measurements should be performed and the results retained for comparison to future measurements.
Penetration measurements should remain fairly consistent over time assuming use of the same system settings
and scanhead. Degradation of the penetration measurement in excess of 1cm may indicate a transducer or system
electronics issue.
Loss of measured penetration may also be caused by degradation (dessication) of the ultrasound phantom.
Ultrasound phantoms used for penetration measurements must also be part of a quality assurance program to
maintain their integrity. Follow all of the phantom manufacturer recommendations for use, storage, and
maintenance of the phantom.
Additional Performance Tests
Color Doppler (Color)
Test
Penetration
1 Use the same scanhead and system settings as previous measurements if possible.
2 Adjust the system controls to obtain a clear image that shows the limits of echo penetration.
3 Press the Freeze key and then save the image.
4 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.
5 Record and retain the results for future reference. Scanhead type and system settings (exam
type, depth, resolution mode, etc.) should also be recorded to ensure proper comparison
with future tests.
6 Press the Freeze key again to return to live imaging.
Test Color 1 Connect any transducer.
2 Press the Color key. “Color” should be annotated in the top left corner of the display.
3 A Region of Interest (ROI) box is displayed on top of the grayscale image. Use the touchpad
to move the Color ROI. Verify that the ROI moves to the new position on the display.
4Adjust the Depth control for minimum depth in the image.
5Adjust the Gain control so that color speckles just appear inside the ROI box.
6 Gently tap the face of the transducer and observe that the ROI box fills with color
information.
7 Press the Freeze key and then save the image. Press the Freeze key again to return to live
imaging.