Choanal atresia

The epidemiology of choanal atresia is not always clear. it is a rare phenomenon having an incidence of between 1 in 6,000 to 1 in 8,000 live births. It exhibits a slightly female-to male preponderance, 51% to 53% versus 49% to 47%, in some studies. The unilateral form of choanal atresia is more common than bilateral, 60% to 64% versus 40% to 36%. The right nasal passage is affected more often than the left in unilateral lesions, and in 90% and more of lesions the atretic portion is bony rather than membranous.