String sign (bowel)

The gastrointestinal string sign (also known as the string sign of Kantor) refers to the string-like appearance of a contrast-filled bowel loop caused by its severe narrowing.

Originally used to describe the reversible narrowing caused by spasms in Crohn disease, it is now used for any severe narrowing of the bowel lumen, including that seen in hypertrophic pyloric stenosis, gastrointestinal tuberculosis, carcinoid tumor and colon cancer.

History and etymology

Described in a short case series of six patients with terminal ileitis by John L Kantor, an American gastroenterologist from New York, in 1934 4. This was only two years after Crohn's seminal paper on his eponymous inflammatory bowel disease.

Share article

Article information

rID: 1375
Section: Signs
Synonyms or Alternate Spellings:
  • String sign of Kantor

Support Radiopaedia and see fewer ads

Cases and figures

  • Case 1: Crohn disease
    Drag here to reorder.
  • Case 2: pyloric stenosis
    Drag here to reorder.
  • Case 3: ileocecal TB
    Drag here to reorder.
  • Case 4: pyloric stenosis
    Drag here to reorder.
  • Updating… Please wait.

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

     Thank you for updating your details.