Ring artifact

Ring artifacts are a CT phenomenon that occurs due to miscalibration or failure of one or more detector elements in a CT scanner. Less often, it can be caused by insufficient radiation dose or contrast material contamination of the detector cover 2. They occur close to the isocenter 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: recalibration of the scanner and inform the referring clinician know that the worrying-looking ring shadows are artifactual. Occasionally, detector elements need replacement which can be costly.

Imaging technology

Article information

rID: 1988
Synonyms or Alternate Spellings:
  • Ring artefacts
  • Ring artifacts
  • Ring artefact

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Cases and figures

  • Case 1: ring artifact
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  • Case 2: ring-artifact 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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  • Case 9
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  • Case 10
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  • Case 11
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  • Case 12
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