Test yourself
Mirror artefact: read the diaphragm
5 questions. Pick an answer to see whether you are right and why. Your score appears at the end.
Question 1What causes the mirror image of the liver above the diaphragm?
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Answer b. The machine assumes the sound travelled in a straight line, so it misplaces the late echoes from the reflected path.
Question 2In the upper quadrant view, what does a mirror image above the diaphragm usually mean?
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Answer a. Air behind the diaphragm makes it a strong reflector. Fluid removes the reflector and the mirror disappears.
Question 3The mirror image is gone and the vertebrae can be followed above the diaphragm. What does this suggest?
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Answer d. Fluid carries sound, so the spine shows above the diaphragm. This is the spine sign of a pleural effusion or haemothorax.
Question 4How can you test whether tissue above the diaphragm is a mirror copy?
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Answer c. A mirror artefact depends on the sound path, so it changes when you change the angle.
Question 5What helps tell consolidated lung from a mirror copy of the liver?
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Answer b. Consolidated lung looks like liver but contains air bronchograms and belongs to the chest. A mirror simply repeats the organ below.
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Four or five delegates per instructor, FAMUS-accredited faculty and long, supervised time on the probe.
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