Bird beak sign (right colon)

The bird beak sign of the right colon is tapering obstruction of the inferior part of right colon seen on contrast enema or CT scan with rectal contrast indicating cecal volvulus.

This sign can help to differentiate cecal volvulus from cecal bascule, in particular on a contrast/barium enema study. A cecal bascule tends to appear as a rounded termination of the contrast/barium column with the cecum folded superiorly, anterior to the ascending colon, instead of a sharp beak-like termination in volvulus.

However, on CT a more specific sign for cecal volvulus is the whirl sign of twisted mesenteric vessels.

Terminology

The term bird beak sign is used in a number of other contexts: see bird beak sign (disambiguation).