Nasal septal cross-over flap technique: a choanal atresia micro-endoscopic surgical repair.

Choanal atresia is a congenital malformation of the posterior portion of the nasal cavity, which is usually unilateral. The incidence is estimated to be 1 in 5,000 to 8,000 live births. Several surgical approaches have been described to correct choanal atresia since Emmert's initial trocar perforation in 1853, including transnasal, transpalatal, transseptal, sublabial transseptal, transantral, and external rhinoplasty.