Tam o' Shanter sign (skull)
Citation, DOI and article data
This imaging sign is named after the Tam o' Shanter, a Scottish hat, named after the character in Robert Burns's 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.
It is important to note that strictly the sign should not be used for Pagetoid involvement of the skull only but more accurately for the additional presence of platybasia, which has been said to be pathognomonic for Paget disease 3.
History and etymology
The way in which "Tam o' Shanter" is represented in text shows a wide range of forms in the medical (and lay) literature. The form used in this article was that used by Robert Burns in the poem of the titular character of the same name and is also that in Chambers Dictionary, one of the authoritative references on the English language 5. As it is a proper noun, it should be capitalized, although as per Burns, the 'o' remains in lower case. Some articles insert a space between the 'o' and 'Shanter', others do not. Moreover, some sources, including at least one established dictionary, insert multiple hyphens, resulting in the somewhat quirky Tam-o' -Shanter or Tam-o'-Shanter sign 3,4.
Other Paget disease-related signs:
- 1. Smith SE, Murphey MD, Motamedi K et-al. From the archives of the AFIP. Radiologic spectrum of Paget disease of bone and its complications with pathologic correlation. Radiographics. 2002;22 (5): 1191-216. Radiographics (full text) - Pubmed citation
- 2. Richards PS, Bargiota A, Corrall RJ. Paget's disease causing an Arnold-Chiari Type 1 malformation: radiographic findings. AJR Am J Roentgenol. 2001;176 (3): 816-7. doi:10.2214/ajr.176.3.1760816 - Pubmed citation
- 3. Mirra JM, Brien EW, Tehranzadeh J. Paget's disease of bone: review with emphasis on radiologic features, Part II. (1995) Skeletal radiology. 24 (3): 173-84. doi:10.1007/BF00228919 - Pubmed
- 4. Oxford Dictionaries. Concise Oxford English Dictionary. (2011) ISBN: 9780199601080
- 5. Chambers of Editors, Chambers. The Chambers Dictionary. (2014) ISBN: 9781473602250