User Guide
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3. Adjust the instrument settings (gain, TGC, output, etc.) as for a “normal”
technique. Record these settings for use on subsequent testing.
4. Align the probe so that the targets are maximized.
5. Freeze the image and obtain a hard copy.
6. Observe the general appearance of the phantom. Note if all regions at the
same depth are displayed with the same intensity across the image.
7. Record your observations.
DEPTH OF PENETRATION TESTING
Depth of penetration, also called maximum depth of visualization or sensitivity, is the
greatest distance in a phantom for which echo signals caused by scattering in the
background material can be detected on the display. The depth of penetration is
determined by the frequency of the transducer, the attenuation of the medium being
imaged and the system settings.
1. Apply coupling gel to the scanning surface or ll the water trough with tap water.
2. Position the transducer to acquire an image of a vertical plane target. (The
wires should appear as dots, not lines).
3. Adjust the instrument settings (gain, TGC, output, etc.) as for a “normal”
technique. Record these settings for use on subsequent testing.
4. Align the probe so that all the vertical targets are displayed at their maximum
intensity level.
5. While actively scanning, look to see where the backscattered echoes within the
background material disappear. Be careful not to confuse electronic noise with
the background backscattered echoes. Electronic noise will move but back-
scattered echoes will remain stationary while maintaining the transducer in a
xed position.
6. Freeze the image.
7. With electronic calipers measure the distance between the scanning surface
and the last identiable echoes due to scattering. Note: Usually the wires stay
visible even though the back scattered echoes are not. Remember to measure
the distance to the scattered echoes, not to the last visible wire.
8. Record this distance on a record sheet and compare with baseline depth.