Trident sign (osmotic demyelination)

Dr Craig Hacking and Dr Ian Bickle et al.

The trident sign describes the typical appearances of the pons in osmotic demyelination syndrome, whereby the symmetrical high T2/FLAIR signal abnormality centrally in the pons is shaped like a trident, the three-pronged spear of classical Greece 1. The predominant involvement of the transverse pontine fibers and relative sparing of the descending corticospinal tracts is responsible for this characteristic ‘trident’ shaped appearance (omega sign) 2.

History and Entomology

The trident is most commonly associated with the sea god Poseidon in Greek mythology or Neptune in the Roman mythology.

Inspired signs
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Article information

rID: 58212
Section: Signs
Tag: stub
Synonyms or Alternate Spellings:
  • Trident shaped appearances (CNS)

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Cases and figures

  • Figure 1: the trident sword
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  • Case 1
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  • Case 2
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  • increased "triden...
    Case 3
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