Which radiographic sign suggests Crohn's disease due to the narrowing of the bowel lumen?

The string sign is a radiographic finding typically associated with Crohn's disease, particularly indicating severe narrowing or stricturing of the bowel lumen. In Crohn's disease, the inflammation can lead to transmural thickening of the bowel wall and result in a reduced lumen, which can be visualized as a string-like appearance on imaging, especially during a barium swallow or barium enema study.

This sign points to the characteristic process of bowel obstruction and the complications that arise from the chronic inflammatory nature of Crohn's. The string sign is most often seen in the terminal ileum but can occur at other segments of the intestine depending on the extent of the disease. It effectively illustrates the constricted nature of the bowel lumen due to the inflammation, which is a hallmark of Crohn's disease.

Other signs mentioned, while relevant in gastrointestinal imaging, do not specifically suggest narrowing as a characteristic of Crohn’s; therefore, their relevance to the context of the question is less direct. Understanding the specific radiographic features associated with conditions like Crohn's disease helps in distinguishing it from other gastrointestinal disorders and emphasizing the importance of imaging in diagnosis.