What causes Steeple sign in airway on frontal neck radiograph?
Let me know in the comments.
Click to reveal the answer
Answer:
Steeple sign: Tapered narrowing of the subglottic trachea due to mucosal edema and inflammation in croup (acute viral laryngotracheobronchitis), most commonly caused by parainfluenza virus.
Why is it called so?
The Steeple sign is named for the tapered, cone-shaped narrowing of the subglottic trachea that resembles the pointed silhouette of a church steeple on frontal radiograph.
Pathophysiology
Viral infection causes submucosal edema and inflammatory thickening in the subglottic region, which is prone to swelling due to its loosely supported structure; this results in symmetrical conical narrowing just below the vocal cords, replacing the normal squared-shoulder appearance.
Alternative names: Wine bottle sign, inverted V sign, pencil-point sign
Other associated named signs: None
Access all radiology signs posted so far: https://radiogyan.com/radiology-signs/
Improve Content And Help Your Colleagues!
Found an error in the post? Please let us know using our contact page and we will update it with due credits!
If you wish to contribute radiological images for this case (or any other article on the website), you can submit them here and you will be duly credited: Submit radiology case