• Etiology: parainfluenza virus
  • Imaging: glottic + subglottic process
    — AP – loss of normal shoulders of subglottic trachea due to subglottic edema = (church) steeple sign
    — Lateral – hypopharynx distension, normal epiglottis/areyepiglottic folds, narrowing or loss of definition of subglottic trachea
  • Clinical: average age 12 months, most common cause acute upper airway obstruction in 6 months – 3 years, symptoms are barky cough due to vocal cord involvement / mild fever / shortness of breath, inspiratory stridor, no dysphagia

Cases of Croup

Radiographs of croup
AP + lateral radiographs of the airway show narrowing of the subglottic trachea (steeple sign) and overdistension of the hypopharynx.