Choanal atresia is a congenital defect that results in an obstruction of one or both nasal airways. A blockage may be caused by a layer of underdeveloped soft tissue or a section of palatine bone that projects across the airways. Most babies who are born with unilateral choanal atresia, with an obstruction on only one side, do not experience severe health problems. Bilateral choanal atresia, however, is a medical emergency that usually requires immediate surgery to prevent respiratory failure.
Doctors are unsure of the exact causes of choanal atresia, though it has been associated with a number of different genetic problems. In healthy fetuses, the nasal airways begin to develop in the second month of gestation and are fully formed well before birth. Many instances of choanal atresia appear when a fetus has a chromosomal disorder, such as Down syndrome or trisomy 18, that also affects the development of other structures and organs. A baby might have congenital heart defects, lung problems, cognitive disabilities, or abnormally shaped eyes and ears.
Unilateral choanal atresia may not be obvious at birth, especially if no other defects are present. A baby may not be diagnosed with the condition until later in life during unrelated medical tests. Bilateral atresia is usually noticeable right away, as a baby is unable to breathe correctly at birth. Newborns typically breathe out of their noses except when they are crying, though it is not possible with a bilateral blockage. An infant may have blue lips and skin and be unable to feed without coughing.
A doctor who suspects choanal atresia usually conducts a computerized tomography scan to confirm the presence of an obstruction. If a bilateral blockage is found, the newborn is typically given a tracheal tube to help him or her breathe and prepare for emergency surgery. The procedure to clear a blockage may be performed through the nose or the mouth, depending on the size, location, and type of tissue structure involved. Soft tissue can usually be punctured and cleared through the nostrils, but a palatine bone obstruction may need to be removed through an incision made in the back of the mouth.
Once the blockage is cleared, the surgeon can insert a stent to hold the nasal airway open until the surrounding tissue has time to heal. Stents are usually removed in one to two months after surgery. Most infants experience full recoveries from choanal atresia surgery, though additional medical care or surgery may be necessary if other health problems persist.