Non-inflammatory laryngeal stridor in infants.

'Congenital laryngeal stridor' is merely a clinical description, and although perhaps 90 % of stridors in young babies are due to an exaggerated pattern of infantile larynx, which rectifies itself with increasing age, it is not safe to assume that this is the cause of the stridor. There are other conditions causing laryngeal stridor in young babies, sometimes from birth, which are graver than the exaggerated infantile larynx, and often prove fatal, and which may be amenable to surgical treatment. Laryngeal stridor in infants is predominantly inspiratory because the infant's larynx narrows on inspiration and blows open on expiration, as is shown in Fig. 1.