CNPAS is a life-threatening form of nasal obstruction in the front of the nasal passages located at the pyriform aperture and was first described in 1989. The nasal passages are severely narrowed due to bony overgrowth in the mid line of the nose and can cause significant respiratory distress in a newborn. For the first 6 to 12 weeks of a newborns life, they are obligate nasal breathers and unable to use their mouth as us adults would if our nasal passages were impaired.
The first symptom of CNPAS is usually respiratory distress. Most of the time it is believed that the newborn is having "swelling" of the nasal passages from being suctioned during the birth, or considered a stuffy baby and dismissed as something that will pass with time. Unfortunately the babies nose will continue to be traumatized with suctioning, which will actually cause the passages to become more swollen and cause greater distress in the child. Symptoms are typically more pronounced during feedings and relieved by crying and supplemental oxygen, when needed.
Most diagnosis of CNPAS occur when a medical professional tries to pass a small catheter into either side of the nose. A lot of times when the catheter is not able to be passed, it is thought that the child may actually have Choanal Atresia, which is much more common than CNPAS. It is not until a CT scan is preformed that a professional can confirm CNPAS. To be considered a diagnosis, the pyriform aperture must be less than 8mm wide.
{CT image of a newborn with normal nasal passages}
{CT image of newborn with CNPAS}
CNPAS is sometimes an isolated anomaly, but usually it is associated with other craniofacial anomalies, or a much bigger condition. CNPAS is frequently associated with Holoprosencephaly (when the brain does not separate completely), hypotelorism (eyes close together), SMMCI, pituitary deficiencies, flat nasal bridge, chromosome abnormalities, narrowed tear ducts and abnormal sinuses.
Some cases of CNPAS are mild enough to just be monitored until the face can grow and hopefully provide more room in the nasal passages. CNPAS repair is needed when the child has cyanosis, apnea, persistent feeding difficulties and inappropriate weight gain. The most common approach to repair the nasal passages is through a sub labial approach. The doctor will make two small incisions under the lip and enter the pyriform aperture area of the nose. He will then drill the bone on either side to open up the nasal passages as much as they can. They can only go so far before they would damage the sinus cavities located next to the nose. Nasal stents are also placed for 4-6 weeks to prevent swelling and re-stenosis (re-narrowing). Re-stenosis is always a possibility, but it is uncommon.
More literature on CNPAS:
* Congenital Nasal Pyriform Aperture Stenosis: Diagnosis and Treatment* Pyriform Aperture Stenosis
* Congenital Nasal Pyriform Aperture Stenosis
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