A: GENERAL

This is the In-Utero failure to open the airway at the back of the nose.  It can present in adults or children and if in the adult, it is usually one side.  In children it can be unilateral (more common and often on the right) or bilateral.  Choanal atresia is the most common congenital abnormality of the nose.  It can either be a narrowing or a complete occlusion and can be bony or a thin membrane.    The incidence is about eight in one hundred thousand births and occurs more often in females than males.  There has been a proven association with more than three cups of coffee a day and smoking.

B: CLINICALLY

The adult will present with a totally blocked one side of the nose with a nasal discharge.  In the neonates, if it is bilateral this can result in rapid death due to asphyxiation.  Classically the child will be pink when crying and then blue when attempting to breathe through the nose.  Neonates are obligate nasal breathers.  In young children, if it is unilateral (or just a narrowing) one can often wait if the obstruction and the sequelae are manageable medically.

60% of these neonates have other abnormalities.  For instance, the CHARGE syndrome, these letters stand for Coloboma (eye,) Heart, Atresia of the nose, Retardation of growth, Genito urinary abnormalities and Ear abnormalities.

C: INVESTIGATIONS

Attempting to pass a thin catheter through the nose will be unsuccessful in choanal atresia and this is usually confirmed using a flexible scope.  The radiology of choice is a CT scan. 

D: MANAGEMENT

In neonates with bilateral choanal atresia, this is a medical emergency and an alternate airway needs to be established either by intubation, oral airways or a modified dummy called a McGoven nipple.  Surgery in children comprises of breaking through the obstruction with dilatation and stenting usually up to six weeks.  Antibiotics are used together with anti-reflux medication.  Definitive surgery is surgery is difficult in these neonates due to the size of the anatomy.  As the child grows further repeat dilatations may be necessary.

In adults, in 1854 the first successful operation for a choanal atresia was performed.  The approach can either be trans-nasal, trans-palatal or trans-septal.  These days the trans-nasal endoscopic approach is most popular using powered instruments and even a laser.  Flap techniques are employed without the use of stents and this has a greater than 90% success rate.