Choanal Atresia in Children
Introduction to Choanal Atresia
Choanal atresia is a congenital disorder characterized by the narrowing or complete obstruction of the posterior nasal apertures (choanae). This condition affects approximately 1 in 5000-8000 live births, with a female predominance. Choanal atresia can be unilateral (more common) or bilateral, and may be bony, membranous, or mixed in nature.
The condition was first described by Johann Rodolphus in 1755, but it wasn't until 1854 that Emmert reported the first successful surgical repair. Understanding this condition is crucial for pediatricians, otolaryngologists, and neonatologists, as prompt diagnosis and management can be life-saving, particularly in bilateral cases.
Pathophysiology of Choanal Atresia
The exact etiology of choanal atresia remains unclear, but it is believed to result from a failure of the bucconasal membrane to rupture during fetal development. This typically occurs between the 6th and 11th week of gestation. Several theories exist regarding its pathogenesis:
- Persistence of the buccopharyngeal membrane from the foregut
- Abnormal mesoderm adhesion in the choanal region
- Misdirection of mesodermal flow due to local factors
Choanal atresia can occur as an isolated defect or as part of syndromic conditions, most notably CHARGE syndrome (Coloboma, Heart defects, Atresia choanae, Retarded growth and development, Genital hypoplasia, Ear anomalies/deafness). Genetic factors, including mutations in the SMAD3 gene and chromosomal abnormalities, have been implicated in some cases.
The obstruction in choanal atresia is typically:
- 90% bony
- 10% membranous
- Often a combination of both
Clinical Presentation
The clinical presentation of choanal atresia varies depending on whether the condition is unilateral or bilateral:
Bilateral Choanal Atresia:
- Presents as a medical emergency in newborns
- Cyclic cyanosis that worsens with feeding and improves with crying
- Respiratory distress and airway obstruction
- Inability to pass a nasogastric tube
Unilateral Choanal Atresia:
- May go undiagnosed until later in childhood
- Unilateral nasal obstruction and discharge
- Difficulty feeding
- Mouth breathing and snoring
Associated anomalies are present in up to 50% of cases, emphasizing the importance of a thorough physical examination and consideration of syndromic associations, particularly CHARGE syndrome.
Diagnosis of Choanal Atresia
Diagnosis of choanal atresia involves a combination of clinical suspicion and imaging studies:
Clinical Diagnosis:
- Inability to pass a small catheter through the nose into the pharynx
- Absence of airflow through the nostrils when breathing
- Failure to fog a metal mirror placed under the nostrils
Imaging Studies:
- CT Scan: Gold standard for diagnosis
- Provides detailed information about the type and extent of the atresia
- Helps in surgical planning
- Nasal Endoscopy:
- Allows direct visualization of the choana
- Can be challenging in neonates due to small nasal passages
Differential diagnosis includes other causes of nasal obstruction such as pyriform aperture stenosis, nasal turbinate hypertrophy, and nasolacrimal duct cysts.
Management of Choanal Atresia
Management of choanal atresia depends on the severity and laterality of the condition:
Emergency Management (Bilateral Cases):
- Secure airway: Oropharyngeal airway or intubation if necessary
- McGovern nipple or other oral airway device
Surgical Management:
- Transnasal Approach:
- Preferred method in most cases
- Can be performed endoscopically
- Lower complication rates and faster recovery
- Transpalatal Approach:
- Used for revision cases or very thick atretic plates
- Provides better exposure but has higher morbidity
Postoperative Care:
- Stenting of the newly created passage (controversial)
- Regular nasal irrigation and debridement
- Close follow-up to monitor for restenosis
Timing of surgery is crucial: bilateral cases require immediate intervention, while unilateral cases can often be managed electively. The choice of surgical approach depends on the patient's age, anatomy, and surgeon's preference.
Complications and Follow-up
Despite advances in surgical techniques, choanal atresia repair can be associated with several complications:
- Restenosis (most common complication)
- Septal perforation
- Synechia formation
- Palatal fistula (in transpalatal approach)
- Eustachian tube dysfunction
Long-term follow-up is essential and typically involves:
- Regular nasal endoscopy to assess patency
- Monitoring of nasal symptoms
- Assessment of facial growth and development
- Evaluation for associated conditions, particularly in syndromic cases
Prognosis is generally good with appropriate management, but patients may require multiple procedures to maintain nasal patency. Early intervention and multidisciplinary care are key to optimizing outcomes in children with choanal atresia.
Choanal Atresia in Children
- Q: What is choanal atresia? A: Congenital obstruction of the posterior nasal aperture(s)
- Q: What is the incidence of choanal atresia? A: Approximately 1 in 5000-7000 live births
- Q: Which gender is more commonly affected by choanal atresia? A: Females (2:1 ratio)
- Q: What is the most common type of choanal atresia? A: Unilateral (60% of cases)
- Q: What is the composition of the obstructing membrane in most cases? A: Mixed bony and membranous (70% of cases)
- Q: What syndrome is commonly associated with choanal atresia? A: CHARGE syndrome
- Q: What is the classic triad of symptoms in bilateral choanal atresia? A: Cyclical cyanosis, respiratory distress, and inability to pass a nasogastric tube
- Q: How do symptoms differ in unilateral choanal atresia? A: Often presents later with unilateral nasal obstruction and discharge
- Q: What is the gold standard imaging technique for diagnosing choanal atresia? A: CT scan of the nasal cavity and nasopharynx
- Q: What is the role of nasal endoscopy in choanal atresia? A: Confirms diagnosis and assesses the nature of the obstruction
- Q: What is the emergency management of a newborn with bilateral choanal atresia? A: Establish an oral airway and consider intubation if necessary
- Q: What is the definitive treatment for choanal atresia? A: Surgical repair
- Q: What are the main surgical approaches for choanal atresia repair? A: Transnasal endoscopic approach or transpalatal approach
- Q: What is the role of stents in the postoperative management of choanal atresia? A: May be used to maintain patency of the newly created opening
- Q: What is the typical duration of stent placement after surgery? A: 2-6 weeks, depending on the severity and surgical approach
- Q: What is the risk of restenosis after choanal atresia repair? A: Up to 30%, may require revision surgery
- Q: What is the role of mitomycin C in choanal atresia management? A: May be applied intraoperatively to reduce the risk of restenosis
- Q: What is the long-term prognosis for children with repaired choanal atresia? A: Generally good, but may require ongoing follow-up and potential revision procedures
- Q: What is the significance of associated anomalies in choanal atresia? A: Present in up to 50% of cases, may affect overall prognosis and management
- Q: What is the role of genetic testing in choanal atresia? A: May be indicated to identify associated syndromes or genetic abnormalities
- Q: What is the appropriate timing for surgical repair of unilateral choanal atresia? A: Can often be delayed until 2-3 years of age or older
- Q: What is the significance of nasal cycle in unilateral choanal atresia? A: May lead to cyclical symptoms as congestion alternates between patent and obstructed sides
- Q: What is the role of nasal saline irrigations in postoperative care? A: Helps maintain patency and prevents crusting
- Q: What is the significance of associated cleft palate in choanal atresia? A: May complicate surgical repair and affect feeding
- Q: What is the role of balloon dilation in choanal atresia management? A: May be used as an adjunct to surgery or for managing restenosis
- Q: What is the appropriate follow-up schedule after choanal atresia repair? A: Regular endoscopic examinations, initially frequent then gradually spaced out
- Q: What is the role of intranasal corticosteroids in postoperative management? A: May help reduce inflammation and granulation tissue formation
- Q: What is the significance of associated craniosynostosis in choanal atresia? A: May indicate presence of syndromic conditions and affect overall management
- Q: What is the role of 3D printing in choanal atresia management? A: Can be used for surgical planning and creating custom stents
- Q: What is the significance of nasal reflexes in newborns with choanal atresia? A: Bilateral atresia can interfere with important reflexes like rooting and sucking
