Subarachnoid FLAIR hyperintensity

Dr Henry Knipe and Radswiki et al.

There is a wide range of causes for subarachnoid FLAIR hyperintensity, both pathological and artifactual. 

Differential diagnosis

Pathological causes
Artifactual causes
  • hyperoxygenation therapy
  • recent gadolinium administration 
    • lasting ~2-24 hours, especially if there is adjacent pathology which involves disruption of the blood-brain barrier, or neovascularisation 7
  • CSF flow artifact
  • vascular pulsation artifact
  • magnetic susceptibility artifact
  • motion artifact
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Article information

rID: 13419
Section: Gamuts
Synonyms or Alternate Spellings:
  • Subarachnoid FLAIR high signal
  • Differential diagnosis for subarachnoid FLAIR hyperintensity

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Cases and figures

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    Case 1
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    Case 2: from moya moya
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    Case 3: from ruptured dermoid
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    Subtle T2 hyperin...
    Case 4: acute right MCA occlusion
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