Choanal Atresia

Introduction

• Definition: Choanal atresia is a congenital condition characterized by the occlusion of the nasal choanae, the openings connecting the nasal cavity with the nasopharynx.
• Types:
  • Unilateral: Presents with mucopurulent discharge and may be asymptomatic if the contralateral side is patent.
  • Bilateral: Causes respiratory distress in neonates as they are obligate nasal breathers.
• Diagnosis: Confirmed via clinical evaluation, nasal endoscopy, and computed tomography.
• Treatment: Surgical intervention, often using transnasal endoscopic techniques.

Etiology

• Development: Choanae develop between the 3rd and 7th embryonic weeks.
• Pathogenesis Theories:
  • Persistence of buccopharyngeal membrane.
  • Persistence of nasobuccal membrane.
  • Incomplete resorption of nasopharyngeal mesoderm.
  • Misdirection of neural crest cell migration.

Epidemiology

• Incidence: Approximately 1 in 5,000 to 1 in 8,000 live births.
• Distribution: More common unilateral than bilateral; historically more common in females, but evidence suggests equal sex distribution.

Pathophysiology

• Neonatal Respiration: Infants are obligate nasal breathers.
• Associated Syndromes:
  • CHARGE syndrome: Includes coloboma, heart defects, atresia choanae, etc.
  • Other syndromes: Crouzon, DiGeorge, Treacher-Collins, Pfeiffer.

Diagnosis

• Clinical Presentation:
  • Bilateral Atresia: Acute respiratory distress, cyanosis relieved by crying.
  • Unilateral Atresia: Nasal discharge, obstruction, possible delayed diagnosis.
• Physical Examination: Key finding is nasal obstruction.
• Imaging: CT scans preferred for detailed analysis.

Treatment and Management

• Urgency: Bilateral cases require immediate intervention, unilateral may be delayed.
• Surgical Techniques:
  • Endoscopic endonasal approach preferred.
  • Stenting and mitomycin C use is controversial.

Prognosis

• Generally favorable with early intervention.
• Complications include restenosis and need for further surgery.

Complications

• Recurrence: Needs monitoring and possible further intervention.
• Surgical Risks: Include infection, bleeding, and injury to surrounding structures.

Postoperative Care

• Use of nasal saline and possibly steroids to prevent crusting and granulation.
• Stents may be used postoperatively to maintain patency.

Conclusion

• Key Consideration: Prompt diagnosis and treatment critical, especially in bilateral cases.
• Surgical Preference: Endoscopic approach is generally favored for its advantages in access and recovery.
• Interprofessional Approach: Necessary for optimal outcomes, especially in cases associated with syndromes like CHARGE.

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