Ring artifact

Ring artifacts are a CT phenomenon that occur due to miscalibration or failure of one or more detector elements in a CT scanner. They occur close to the isocentre of the scan and are usually visible on multiple slices at the same location. They are a common problem in cranial CT.

The remedy is usually simple, recalibrate the scanner and let the referrer know that the worrying-looking ring shadows are artefactual.

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Article information

rID: 1988
Section: Physics
Synonyms or Alternate Spellings:
  • Ring artefacts
  • Ring artifacts
  • Ring artifact

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Cases and figures

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    Case 1: ring artefact
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    Case 2: ring-artefact after reconstruction
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    Case 3: streak, beam hardening and ring artifacts
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    Case 4
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    Case 5
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    Case 6
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    Case 7: partial ring
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    Case 8
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