Tracheal dyskinesia associated with midline abnormality: embryological hypotheses and therapeutic implications.

Abnormalities of tracheal rigidity, which may lead to the collapse of the airway during expiration and consequent complications, characterize two groups of disorders: tracheomalacia (weakness of the anterior cartilaginous arc of the trachea) and tracheal dyskinesia (dysfunction of the posterior membranous trachea). Tracheal dyskinesia can either be isolated or associated with a more complex syndrome of malformations: esophageal atresia, tracheoesophageal fistula and laryngotracheal cleft. Although our knowledge of the embryological development of the tracheoesophageal axis remains limited, the existence of these 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 therapeutic management of the first malformation. In particular, the postoperative follow-up is often more difficult, and a long-term tracheostomy is often required (sometimes for several years). However, it must be pointed out that tracheal dyskinesia, even in the associated forms, has a good longterm prognosis, since spontaneous resolution as the child grows up is the rule.