Laryngomalacia is the most frequent cause of stridor or noisy breathing in infants. It occurs as a result of a floppy portion of the larynx (voice box) that has not yet developed the strength to provide rigid support of the airway. During inspiration, negative pressure is created through the larynx, which results in a collapse of these structures into the airway and a narrower breathing passage. The partial obstruction is the source of the noise with breathing.
The hallmark sign includes a high pitched or squeaky intermittent sound noted mostly on inspiration. It is usually more prominent when the infant is lying on his/her back, crying, feeding, excited or has a cold. This is usually first noticed in the first few weeks of life. It may worsen over the first few months and become louder. This is because as the baby grows, the inspiratory force is greater, which causes greater collapse of the laryngeal structures into the airway. This is usually at it’s worst at 3-6 months and then gradually improves as the rigidity of the cartilage improves. Most children are symptom free by 12 months.
It is usually a self-limited condition, but it can be associated with gastroesophageal reflux, neuromotor disease, and obstructive apnea. Infants with severe laryngomalacia may require supraglottic surgery to prevent the consequences of neonatal upper airway obstruction.