OnyxTM is the trade name for a liquid embolic agent used in interventional radiology for the occlusion of blood vessels in embolization therapy. It is an elastic copolymer (ethylene vinyl alcohol copolymer (EVOH)), dissolved in dimethyl-sulfoxide (DMSO). Micronised tantalum powder is also added as an ingredient to provide radiopacity.

It comes in two strengths:

  • Onyx 18: 6% ethylene vinyl alcohol
  • Onyx 34: 8% ethylene vinyl alcohol

History and etymology

It was first described by Taki et al. in 1990 4.

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Article information

rID: 34813
Synonyms or Alternate Spellings:
  • Ethylene vinyl alcohol copolymer
  • EVOH

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Cases and figures

  • Case 1: used in cerebral embolization
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