Laryngomalacia

Evaluation of a child with an inspiratory stridor is a frequent request. Most commonly, inspiratory stridor is caused by laryngomalacia. Laryngomalacia is caused by a characteristic infolding of the aryepiglottic folds, which obstruct the airway. This is self-limiting and improves by 1-2 years of age. If laryngomalacia is excluded, tracheomalacia is considered. The diagnosis can be made by bronchoscopy, but the radiologist may be asked to image the child to identify the tracheomalacia and to look for a cause such as a vascular anomaly.

Lateral fluoroscopy can identify the collapse of the trachea with expiration confirming tracheomalacia. Additionally, CT bronchoscopy in both inspiration and expiration with a CTA is very helpful in answering these questions. MRI offers the same advantages as CT in dynamically examining the airway and looking at the vascular anatomy, but does not have the cost of the radiation dose. The disadvantage is that sedation is usually necessary for MRI whereas it is not usually needed for CT. Other etiologies for inspiratory stridor include infectious conditions, which will be discussed in the following section. Neck masses such as hemangiomas and cystic hygromas will not be discussed.