Piglet sign (osmotic demyelination)

Last revised by Dr Yair Glick on 20 Apr 2020

The piglet sign is seen in osmotic demyelination syndrome. It refers to the appearance of the upper pons in axial T2 and FLAIR images. The areas of coalescent T2 signal increase are reminiscent of a pig's snout, with other features on axial MR images resembling the rest of the face of a piglet with the temporal lobes representing ears, the carotid arteries represent the eyes and the fourth ventricle as the mouth 1,2.

The area of abnormally increased T2 signal is perhaps better known as the trident sign

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Case 1
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.