Tracheal dyskinesia associated with midline abnormality: Embryological hypotheses and therapeutic implications

Abnormalities of tracheal rigidity, which may lead to the collapse of the a irway during expiration and consequent complications, characterize two grou ps of disorders: tracheomalacia (weakness of the anterior cartilaginous arc of the trachea) and tracheal dyskinesia (dysfunction of the posterior memb ranous trachea). Tracheal dyskinesia can either be isolated or associated with a more comple x syndrome of malformations: esophageal atresia, tracheoesophageal fistula and laryngotracheal cleft. Although our knowledge of the embryological deve lopment of the tracheoesophageal axis remains limited, the existence of the se associations suggests that tracheal dyskinesia is of congenital origin. The presentation of three clinical cases demonstrates that the coexistence of a midline malformation and of tracheal dyskinesia complicates the therap eutic management of the first malformation. In particular, the postoperativ e follow-up is often more difficult, and a long-term tracheostomy is often required (sometimes for several years). However, it must be pointed out tha t tracheal dyskinesia, even in the associated forms, has a good longterm pr ognosis, since spontaneous resolution as the child grows up is the rule.