Subglottic tracheal narrowing

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. [Source: Wikipedia ]

May Be Caused by

Common: Aberrant left subclavian artery; Anterior tracheal indentation; Carcinoma; Croup; Double aortic arch; External trauma; Goiter; Hematoma; Innominate artery compression syndrome; Intubation; Localized retropharyngeal abscess; Lymphadenopathy; Lymphangioma; Lymphoma; Normal expiratory collapse; Paratracheal cyst; Posttracheostomy fibrosis; Repair of esophageal atresia; Right aortic arch; Subglottic hemangioma; Tracheomalacia
Uncommon: Acid aspiration; Adenoma; Amyloidosis; Aspirated tracheal foreign body; Congenital subglottic stenosis; Congenital tracheal stenosis x; Cyst; Ectopic goiter; Ectopic intratracheal thymus tissue; Ectopic intratracheal thyroid tissue; Epidermolysis bullosa; Fibroma; Impacted food; Inflammatory histiocytoma; Juvenile papillomatosis; Lipoid proteinosis; Lipoma; Lye; Mucocele; Papilloma; Polyp; Polypoid hemangioendothelioma; Radiation therapy; Rhinoscleroma; Smoke; Thermal injury; Tuberculosis