Choanal atresia is a birth defect where the back of the nasal passage is blocked. This blockage, present from birth, can be due to abnormal bone or soft tissue, preventing air from flowing from the nose to the throat. The condition affects breathing and can range in severity.
Understanding the Condition
Choanal atresia is a congenital malformation that develops during pregnancy. It occurs when tissues that normally separate the nasal cavity from the mouth during fetal development fail to resorb, leading to an obstruction at the back of the nasal passages, known as the choana.
The blockage can be composed entirely of bone or a combination of bone and soft tissue (membranous). The condition can affect one side (unilateral) or both sides (bilateral) of the nasal passage. Unilateral choanal atresia is more common, affecting about twice as many individuals as bilateral cases. Bilateral choanal atresia, where both nasal passages are blocked, is a more severe form that can be life-threatening for newborns. The incidence is approximately 1 in 5,000 to 7,000 live births, with a slight predominance in females.
Recognizing the Signs
The signs of choanal atresia depend on whether one or both nasal passages are affected. Newborns are obligate nasal breathers, so bilateral choanal atresia presents as an immediate and severe breathing emergency at birth. Infants may experience cyanosis, a bluish discoloration of the skin and lips, due to lack of oxygen. These breathing difficulties often improve temporarily when the baby cries, as crying forces them to breathe through their mouth.
Other signs include noisy breathing and difficulty feeding, as the infant cannot breathe through their nose while nursing. In cases of unilateral choanal atresia, symptoms are often much milder and may not be noticed until later in infancy or childhood. These subtler signs can include persistent, one-sided nasal discharge, chronic stuffy nose, or recurrent sinus infections on the affected side.
Confirming the Diagnosis
Medical professionals often suspect choanal atresia immediately after birth in cases of bilateral obstruction. Initial suspicion can arise from attempting to pass a small catheter through the infant’s nose into the throat; resistance indicates a blockage. This test can indicate an obstruction at approximately 3-3.5 cm from the nostril.
To confirm the diagnosis, imaging techniques are employed. Flexible fiberoptic endoscopy, where a thin tube with a camera is inserted into the nose, is a common method to visually inspect the nasal passages. A computed tomography (CT) scan is the preferred imaging method. A CT scan provides detailed 3D images that reveal the extent of the blockage, whether it is bony or membranous, and aids in surgical planning.
Treatment Options
Bilateral choanal atresia requires immediate intervention to secure an airway, as newborns primarily breathe through their noses. Before definitive surgery, an oral airway or endotracheal intubation may be used to stabilize the infant and ensure adequate breathing.
Surgical repair is the primary treatment. The most common approach is transnasal endoscopic repair, which is minimally invasive. During this procedure, instruments are inserted through the nostrils to create an opening through the blocked choana. The surgeon may use specialized tools to remove obstructions, sometimes removing a portion of the posterior septum or vomer bone to create a wider passage. After the procedure, temporary silicone stents may be placed for several weeks to help maintain the opening and prevent scar tissue from re-forming.
Life After Treatment
The prognosis for individuals with choanal atresia is generally favorable following successful surgical correction. Regular follow-up appointments monitor the nasal passages for restenosis, the re-narrowing of the airway due to scar tissue formation. Restenosis can occur, and some patients, particularly those with associated anomalies, may require repeat procedures to maintain airway patency.
Patients are often advised to perform nasal saline irrigations to keep the passages clear. Choanal atresia can be associated with other congenital conditions, such as CHARGE syndrome. Developmental delays, particularly related to feeding or speech, can occur and may require ongoing therapy.