Comet tail sign (chest)

Dr Daniel J Bell and Radswiki et al.

The comet tail sign is a finding that can be seen on CT scans of the chest. It consists of a curvilinear opacity that extends from a subpleural "mass" toward the ipsilateral hilum. The comet tail sign is produced by the distortion of vessels and bronchi that lead to an adjacent area of round atelectasis, which is the mass. The bronchovascular bundles appear to be pulled into the mass and resemble a comet tail.

Adjacent pleural thickening is almost always seen and well demonstrated at CT. On administration of IV contrast, homogenous enhancement is seen. This, however may also be seen in carcinomas and hence cannot be used as a differentiating feature.

It should not be confused with:

Inspired signs
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Article information

rID: 12102
System: Chest
Section: Signs
Synonyms or Alternate Spellings:
  • Comet tail sign in a CT chest scan
  • Comet tail sign - CT chest

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Cases and figures

  • Comet tail (photo)
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  • Case 1
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  • Case 2
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