Comet Tail Artefact

At the same time that astronomers are seeing comets in the heavens, we are seeing comets without even going outdoors. This 85 year-old woman presented with abdominal pain. In her liver were multiple small echogenic foci with comet-tail artefact. Comet-tail artefact arises from reverberation of the ultrasound beam within a small cyst or gas bubble. The multiple echoes generated register as a trail on the image.
Comet-tail artefact arising within the liver may be due to gas (portal venous gas or biliary tree gas). The appearance may also be seen with von Meyenberg complexes (biliary hamartomas), a benign condition found in up to 5% of the population.
Reference: Rumack CM et al. Diagnostic Ultrasound, 3rd edition. Elsevier 2005.
Credit: Dr Laughlin Dawes
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