Overview
Definition:
Congenital choanal atresia is a condition characterized by the blockage of the posterior nasal choanae, the nasal passages that open into the nasopharynx
It can be unilateral or bilateral, and bony or membranous in nature
Bilateral choanal atresia is a critical emergency in neonates due to obligate nasal breathing.
Epidemiology:
It is the most common congenital anomaly of the nasal pyramid, occurring in approximately 1 in 5,000 to 8,000 live births
It is more common in females (2:1 ratio) and is associated with other congenital anomalies in up to 50% of cases, forming part of syndromes like CHARGE syndrome, Treacher Collins syndrome, or Klippel-Feil syndrome.
Clinical Significance:
Undiagnosed or inadequately managed choanal atresia, especially bilateral, can lead to significant respiratory distress and failure to thrive in neonates
Early diagnosis and appropriate surgical intervention are crucial for securing the airway, enabling proper feeding, and preventing long-term complications such as chronic sinusitis and velopharyngeal insufficiency.
Clinical Presentation
Symptoms:
In neonates: Persistent cyclical cyanosis that improves with crying
Difficulty breathing, particularly when feeding, leading to apneic spells
Inability to pass a catheter through the nasal cavity
Older children/adults: Chronic unilateral nasal obstruction
Recurrent sinusitis
Nasal discharge
Mouth breathing
Snoring.
Signs:
In neonates: Tachypnea and respiratory distress
Cyanosis
Absence of airflow from the affected nostril
Inability to pass a 6Fr or 8Fr catheter beyond 5.5 cm posteriorly
Palpation may reveal a physical obstruction in the nasopharynx
Associated craniofacial anomalies may be present.
Diagnostic Criteria:
Diagnosis is primarily clinical and confirmed by objective tests
A neonate presenting with cyclical cyanosis and relief with crying is highly suspicious
Confirmation involves failure to pass a soft catheter (e.g., 6Fr feeding tube) through the nasal cavity to the pharynx, or visualization of the atresia via nasendoscopy or CT scan.
Diagnostic Approach
History Taking:
Detailed history of neonatal respiratory status, including cyanosis and its relation to feeding and crying
Any history of prolonged intubation or difficulty with nasal intubation
History of recurrent sinus infections or chronic nasal blockage in older children
Inquiry about associated congenital anomalies or syndromes.
Physical Examination:
Thorough examination of the nasal airway, including attempt to pass a small caliber catheter
Evaluation of the oral cavity and oropharynx
Assessment for other congenital anomalies (ear, eye, cardiac, skeletal)
Detailed otolaryngological examination including nasendoscopy under topical anesthesia where feasible.
Investigations:
Nasendoscopy: Direct visualization of the choanal obstruction, determining if it is bony or membranous, and its extent
CT scan of the paranasal sinuses: Provides detailed anatomical information, differentiating bony from membranous atresia, assessing the thickness of the bone, and identifying associated anatomical variations or other sinus pathologies
It is gold standard for bony atresia and assessment for surgical planning
Plain radiographs are less informative.
Differential Diagnosis:
Other causes of neonatal nasal obstruction: Choanal stenosis
Nasal polyps (rare in neonates)
Nasal masses (e.g., teratoma, rhabdomyosarcoma)
Nasal pyriform aperture stenosis
Mid-face hypoplasia
Pierre Robin sequence
Macroglossia.
Management
Initial Management:
For neonates with bilateral choanal atresia: Immediate airway management is paramount
Oral airway or nasopharyngeal airway insertion to maintain patency
Feeding should be carefully managed, often via oral or nasogastric tube, to prevent aspiration and hypoxemia
Stabilization in a NICU setting with continuous monitoring.
Surgical Management:
Surgical intervention is indicated for symptomatic choanal atresia, especially in neonates
The goal is to create a patent airway through the choanae
Surgical approaches include: Transnasal endoscopic repair: Minimally invasive, uses microdebriders or drills to remove the atresia
Preferred method for membranous and thinner bony atresias
Transpalatal repair: Used for thicker bony atresias or when transnasal access is difficult
Involves midline palate incision
Stenting is often required post-operatively to maintain patency
Nasoendoscopic techniques are evolving and becoming the primary choice.
Supportive Care:
Postoperative care involves airway monitoring, pain management, and meticulous nasal hygiene
Stent care and removal are critical
Antibiotics may be prescribed to prevent infection
Nutritional support is crucial for adequate growth and recovery, especially after extensive surgery.
Complications
Early Complications:
Hemorrhage from the nasal cavity
Infection at the surgical site
Nasal synechiae formation
Damage to nasal turbinates or mucosa
Recurrent obstruction due to granulation tissue
Airway compromise if the repaired choanae become occluded.
Late Complications:
Chronic nasal obstruction or stenosis
Persistent sinusitis
Velopharyngeal insufficiency (VPI) due to altered nasopharyngeal anatomy
Nasal septal deviation
Dental malocclusion
Sensory deficits in the nasal mucosa.
Prevention Strategies:
Meticulous surgical technique, especially in preserving nasal mucosa and turbinates
Appropriate use and management of nasal stents to prevent synechiae and stenosis
Regular postoperative follow-up and nasal saline irrigations
Early recognition and management of granulation tissue or stenosis.
Prognosis
Factors Affecting Prognosis:
The extent and type of atresia (membranous vs
bony), presence of associated anomalies, success of surgical reconstruction, and adherence to postoperative care and follow-up are key factors
Early diagnosis and intervention generally lead to better outcomes.
Outcomes:
Successful surgical repair provides a patent airway, resolves respiratory distress, and allows for normal feeding and breathing
Long-term outcomes are generally good with minimal sequelae, but some patients may experience chronic nasal symptoms or require revision surgery.
Follow Up:
Regular follow-up appointments are essential, particularly in the immediate postoperative period, to monitor stent patency, assess for stenosis or synechiae, and manage any complications
Long-term follow-up may be required to address chronic sinusitis or velopharyngeal issues.
Key Points
Exam Focus:
Bilateral choanal atresia in neonates is an airway emergency due to obligate nasal breathing
The characteristic symptom is cyclical cyanosis relieved by crying
Diagnosis is confirmed by failure to pass a catheter or nasendoscopy
CT scan is vital for bony atresia assessment
Transnasal endoscopic repair is the preferred modern approach
Stenting is crucial for maintaining patency.
Clinical Pearls:
Always suspect choanal atresia in a neonate with respiratory distress and cyclical cyanosis
A simple 6Fr catheter test is a quick bedside diagnostic tool
If performing nasendoscopy, ensure adequate topical anesthesia and consider sedation for infants
For bony atresia, CT imaging is indispensable for surgical planning
Aggressive management of nasal stents and regular saline irrigations post-op are key to preventing restenosis.
Common Mistakes:
Delayed diagnosis of bilateral choanal atresia leading to critical airway compromise
Over-reliance on plain radiographs instead of CT for bony atresia evaluation
Inadequate stenting or premature removal leading to synechiae and restenosis
Aggressive tissue removal during surgery causing damage to turbinates or mucosa, leading to long-term problems
Neglecting associated congenital anomalies, which can significantly impact overall patient management and prognosis.