Overview
Definition:
Choanal atresia is a congenital condition characterized by the blockage of one or both nasal choanae by membranous or bony tissue
It is the most common congenital anomaly of the nasal cavity, occurring when the posterior nasal aperture fails to develop properly during fetal development.
Epidemiology:
The incidence of choanal atresia is estimated to be between 1 in 5,000 to 1 in 8,000 live births
It is more common in females (2:1 ratio)
Bilateral atresia is less common than unilateral but presents with more severe respiratory distress
It can be isolated or associated with other congenital anomalies, forming part of syndromes like CHARGE syndrome (Coloboma, Heart defects, Atresia choanae, Retardation of growth/development, Genital abnormalities, Ear abnormalities).
Clinical Significance:
Choanal atresia is a critical diagnosis in neonates due to the obligate nasal breathers
Obstruction can lead to severe respiratory distress, cyanosis, and feeding difficulties
Prompt diagnosis and management are essential to prevent life-threatening complications and ensure adequate nutrition and growth
Differentiating between unilateral and bilateral forms is crucial for immediate management decisions.
Clinical Presentation
Symptoms:
Neonates with bilateral choanal atresia present with cyclical cyanosis that improves with crying and worsens with feeding
Difficulty breathing is evident even at rest
Infants may have noisy breathing and oral breathing
Unilateral choanal atresia may be asymptomatic or present with chronic unilateral nasal discharge, mouth breathing, and nasal obstruction on one side, often noticed later in infancy or childhood
Failure to pass a catheter through the nasal cavity is a key sign.
Signs:
Cyclical cyanosis (resolves with crying) in neonates
Oral breathing is evident
Increased respiratory effort
Inability to pass a 6-8 Fr catheter beyond 6-7 cm in the nasal cavity
Unilateral nasal discharge or obstruction
Associated features may be present if part of a syndrome.
Diagnostic Criteria:
Diagnosis is primarily clinical, confirmed by inability to pass a nasogastric tube or a flexible catheter through the nasal cavity into the oropharynx
Confirmation by imaging, such as CT scan, is often performed, especially to delineate the extent and type (membranous vs
bony) of atresia.
Diagnostic Approach
History Taking:
Key historical points include the onset of breathing difficulties, whether cyanosis is cyclical and improves with crying, and feeding patterns
A detailed family history for similar anomalies and a review for other congenital anomalies are important
For unilateral cases, history of chronic nasal discharge or obstruction on one side should be elicited.
Physical Examination:
Thorough examination of the infant's airway, noting respiratory rate, effort, and oxygen saturation
Attempt to pass a small caliber (6-8 Fr) catheter or NG tube through each nostril to the posterior pharynx
Observe for cyclical cyanosis
A full physical examination to identify other congenital anomalies, particularly those associated with CHARGE syndrome or other known genetic syndromes.
Investigations:
The primary investigation is the attempt to pass a catheter through the nasal cavity
If successful, choanal atresia is ruled out
If unsuccessful, a CT scan of the paranasal sinuses with thin axial and coronal slices is the gold standard imaging modality to confirm the diagnosis, delineate the type (membranous or bony), thickness, and extent of the atresia, and assess for associated bony anomalies.
Differential Diagnosis:
Other causes of neonatal nasal obstruction include nasal pyriform aperture stenosis, nasal masses (teratoma, encephalocele), congenital nasal obstruction secondary to severe micrognathia (Pierre Robin sequence), and midface hypoplasia
Conditions causing cyclical cyanosis include congenital heart disease and severe tracheoesophageal fistula.
Management
Initial Management:
For bilateral choanal atresia in a neonate, immediate management focuses on securing an airway
This involves placing an oral airway or an oral-pacifier device to maintain an open airway
Oxygen therapy is crucial
If the infant cannot maintain adequate oxygenation with these measures, endotracheal intubation may be necessary
Feeding should be done via a nasogastric tube to avoid airway compromise during sucking.
Medical Management:
Medical management is primarily supportive and involves ensuring adequate oxygenation and nutrition
Antibiotics may be indicated for associated infections
Long-term medical management is not typically the primary approach for choanal atresia
surgical correction is usually required.
Surgical Management:
Surgical correction is indicated for both unilateral and bilateral choanal atresia, especially if symptomatic
The goal is to create an open airway through the choanae
Treatment options include: Transnasal endoscopic repair: This is the preferred method, especially for membranous atresia or thinner bony atresia
It involves using microdebriders, drills, or lasers to create a patent choana
Stenting the repaired choana with a silicone stent is often employed to prevent restenosis
Transpalatal repair: This approach is typically used for thicker bony atresia or when endoscopic access is challenging
It involves incising the palate to access and widen the choanae
Tracheostomy: May be required as a temporizing measure in severe cases of bilateral choanal atresia with significant respiratory distress, especially if surgical correction is delayed or unsuccessful
It is usually decannulated once a patent airway is established
Unilateral atresia management is usually surgical, aiming to create a patent airway through the affected side.
Supportive Care:
Postoperative care includes monitoring for bleeding, infection, and airway patency
Stent care and removal are crucial
Adequate hydration and nutrition, often via NG tube initially, are essential
Close monitoring of respiratory status and oxygenation is vital, especially after surgery
Parents require education on home care, including nasal hygiene and recognition of complications.
Complications
Early Complications:
Bleeding from the surgical site
Infection of the nasal cavity or surgical site
Airway obstruction due to edema or hematoma
Accidental dislodgement or obstruction of the nasal stent
Failure of the repair, leading to restenosis.
Late Complications:
Restenosis of the repaired choana
Chronic sinusitis
Nasal synechiae formation
Persistent nasal obstruction or discharge
Speech and dental abnormalities due to altered oral-nasal airflow
Recurrence of symptoms if the underlying cause of obstruction (e.g., associated syndrome) is not addressed.
Prevention Strategies:
Meticulous surgical technique to minimize trauma and bleeding
Proper placement and secure fixation of nasal stents
Prompt recognition and management of postoperative complications
Close follow-up to monitor for restenosis and address it early
Comprehensive assessment for and management of associated congenital anomalies.
Prognosis
Factors Affecting Prognosis:
The presence and severity of associated congenital anomalies significantly impact prognosis
The type and extent of atresia (membranous vs
bony, unilateral vs
bilateral) and the success of surgical repair are critical factors
Early diagnosis and prompt, appropriate management lead to better outcomes.
Outcomes:
With timely and successful surgical intervention, the prognosis for isolated choanal atresia is generally good
Neonates can achieve adequate nasal breathing, leading to improved feeding and growth
Long-term outcomes depend on the successful establishment of a patent airway and management of any associated conditions
Bilateral atresia, especially if requiring tracheostomy, may have a more complex recovery.
Follow Up:
Regular follow-up is required to monitor for stent complications, restenosis, chronic sinusitis, and other long-term sequelae
This typically involves periodic nasal examinations and potentially repeat imaging
Further interventions may be necessary if restenosis occurs
Long-term monitoring for associated syndromes is also crucial.
Key Points
Exam Focus:
Bilateral choanal atresia is a neonatal emergency due to obligate nasal breathing
cyclical cyanosis improving with crying is a pathognomonic sign
Unilateral atresia is often diagnosed later
CT scan is the gold standard for diagnosis and assessment of atresia type
Transnasal endoscopic repair is the preferred surgical approach, often with stenting.
Clinical Pearls:
Always attempt to pass a catheter through the nose in any neonate with respiratory distress or cyclical cyanosis
Never feed orally until bilateral choanal atresia is ruled out in a symptomatic neonate
Early recognition and intervention are paramount for survival and optimal development.
Common Mistakes:
Failing to consider choanal atresia in neonates with respiratory distress
Delayed diagnosis of bilateral choanal atresia leading to significant morbidity or mortality
Inadequate initial management of airway in neonates with bilateral atresia
Poor follow-up leading to undetected restenosis.