Differential Diagnosis for Inspiratory Stridor Heard Loudest Over the Neck

• Single Most Likely Diagnosis
  • Laryngomalacia: This condition is the most common cause of inspiratory stridor in infants, characterized by softening of the tissues of the larynx (voice box) which can cause partial airway obstruction when inhaling. The stridor is typically loudest over the neck.
• Other Likely Diagnoses
  • Vocal cord paralysis: This can cause inspiratory stridor due to the inability of one or both vocal cords to move properly, affecting the airway opening during inhalation.
  • Subglottic stenosis: A narrowing of the airway below the vocal cords can cause inspiratory stridor, especially if the narrowing is significant enough to impede airflow.
  • Tracheomalacia: Similar to laryngomalacia, tracheomalacia involves softening of the tracheal walls, which can lead to collapse of the trachea during inhalation, producing stridor.
• Do Not Miss Diagnoses
  • Epiglottitis: Although less common, epiglottitis is a life-threatening condition that can cause inspiratory stridor due to inflammation of the epiglottis, which can obstruct the airway. Prompt recognition and treatment are crucial.
  • Foreign body aspiration: The presence of a foreign object in the airway can cause sudden onset of stridor and is a medical emergency requiring immediate intervention.
• Rare Diagnoses
  • Laryngeal webs or cysts: Abnormal tissue formations in the larynx can cause inspiratory stridor by obstructing airflow.
  • Vascular rings or slings: These are congenital anomalies of the aortic arch that can compress the trachea or esophagus, leading to stridor among other symptoms.
  • Tumors of the larynx or trachea: Although rare, especially in children, tumors in the airway can cause stridor by physically obstructing airflow.