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Tam o' shanter sign (skull)

The "tam o' shanter" is a Scottish hat, named after the character in Robert Burns' 1 poem of the same name. The appearances of advanced Paget disease of the skull are similar in appearance to the hat. 

Paget involvement of the skull, with widening of the diploic space and an overall enlargement of the cranium, combined with platybasia, leads to the appearance of the skull falling over the facial bones, such as a tam o' shanter hat would fall over the head.  

See also

Other Paget disease related signs:

Inspired signs
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Article information

rID: 2146
Section: Signs
Synonyms or Alternate Spellings:
  • The tam O'shanter sign
  • Tam O'Shanter Deformity

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Cases and figures

  • Tam o' shanter hat (photo)
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  • CT Scout
    Case 1: Paget disease of the skull
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  • Case 2
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