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. The presence of the steeple sign supports a diagnosis of croup, usually caused by paramyxoviruses. 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.

The steeple sign is also referred to as the minaret sign, with this name sometimes used interchangeably and sometimes referring to a more narrow but less pointed appearance. This alternative name is also used to avoid giving the appearance of a Christian-centric focus, especially in nations where minarets are more common than steeples.

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