Steeple sign

In radiology, the steeple sign is a radiologic sign found on a frontal neck radiograph where subglottic tracheal narrowing produces the shape of a church steeple within the trachea itself.^[1][2] The presence of the steeple sign supports a diagnosis of croup, usually caused by paramyxoviruses.^[3] It can also be defined as the replacement of the usual squared-shoulder appearance of the subglottic area by cone-shaped narrowing just distal to the vocal cords. This is called the steeple or pencil-point sign.

Steeple sign
The steeple sign as seen on an anteroposterior neck X-ray of a child with croup
Differential diagnosis	Croup