Unilateral choanal atresia in identical twins: case report and literature review.

Choanal atresia is postulated to be secondary to an abnormality of the rupture of the buccopharyngeal membrane during the embryological period. This condition usually occurs sporadically, but has been described in siblings and successive generations. The genetics remain unclear. We present monozygotic twins with identical findings of unilateral choanal atresia and no other associated anomalies. To our knowledge, this is the first report of such an occurrence.