Laryngomalacia is the most common congenital malformation of the laryngeal cartilage.  This malformation is the most common cause of stridor in newborns and infants and was initially known as ‘congenital laryngeal stridor’.
Anatomically, the laryngeal abnormality corresponds to a mucosal excess with collapse of the supraglottic structures during inspiration, this leading to airway obstruction. 
The neurological theory recognizes that laryngomalacia may be a consequence of an underdeveloped neuromuscular laryngeal control system, associated with weak cartilaginous support, together resulting in the collapse of the supraglottic region of the larynx (Central pharyngo-laryngomalacia).
 
In its habitual form, the stridor of laryngomalacia appears directly after birth or within the first few days of life.  This stridor is usually high-pitched and typically worsens with feeding, crying, supine positioning and agitation.
 
There is no correlation between the severity of laryngomalacia and the intensity of the stridor.  The severity is evaluated based on the duration of feeding, the presence of feeding difficulties, weight loss and failure to thrive.  Severe airway obstruction can similarly lead to dyspnea and respiratory distress.
 
The clinical evolution of laryngomalacia is favorable in the majority of cases.  In the cases where the disorder is limited to an isolated stridor, management can be done by respiratory surveillance and evaluation of weight gain.
Severe laryngomalacia might require surgical intervention.  The most common indications of surgery are stridor with respiratory compromise and feeding difficulties with failure to thrive.  The surgical procedure consists of the resection of the lateral borders of the epiglottis and the removal of the redundant arytenoid mucosa.  This procedure can be performed by the use of micro-instruments or laser.

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