What is choanal atresia and how is it treated?

Choanal Atresia: Comprehensive Overview

Definition and Epidemiology

Choanal atresia is a congenital malformation where a widened vomer fuses with the narrow posterior nasal airway to form an atretic plate (either bony or membranous), resulting in an hourglass configuration of the nasopharynx and choanal region. 1

• Incidence: 1 in 7,000-8,000 live births 1
• Female predominance: 2:1 ratio 1
• Bilateral vs. unilateral: 40% bilateral, 60% unilateral 1
• Composition of atretic plate: 30% purely bony, 70% mixed bony and membranous 1

Associated Anomalies

• 50% of cases have associated congenital abnormalities, rising to 75% in bilateral manifestations 1
• CHARGE syndrome is the most frequent syndromal association (20% of cases), requiring two of the following: Coloboma, Heart defects, Choanal Atresia, Retardation, Genito-urinary abnormalities, and Ear abnormalities 1, 2
• Other associated malformations include meningoceles, hypertelorism, and clefts 1

Clinical Presentation

Bilateral Choanal Atresia

Bilateral atresia presents as a neonatal emergency because newborns are obligate nasal breathers during the first 3-4 weeks of life. 1

• Periodic respiratory distress and cyanosis that is relieved by crying 1, 3
• Severe feeding problems and aspiration 1
• Pallor alternating with cyanosis 1
• Immediate airway management with oropharyngeal airway intubation is required within the first hours of life 1, 4

Unilateral Choanal Atresia

• Mucoid nasal discharge (most common complaint) 1
• Upper airway infections 1
• Headache 1
• Rhinolalia 1

Diagnostic Workup

State-of-the-art diagnosis includes thorough endoscopic examination and multi-slice high-resolution CT scan with multiplanar reconstructions to analyze individual anatomical topography and the nature of the atretic plate. 1, 2

• Inability to pass a catheter through either nostril into the pharynx is a simple diagnostic test 1, 2
• Endoscopic examination confirms the diagnosis 1, 4
• High-resolution CT with three-dimensional reconstructions is essential for preoperative planning to identify the "delta deformity" of the widened vomer and any associated skull base defects 1, 2

Surgical Management

Timing of Intervention

For bilateral atresia, surgical correction must be performed within the first days of life due to the life-threatening nature of the condition. 1, 2, 3

For unilateral atresia, elective surgical correction should be performed before school age, preferably around 2 years of age. 1, 2 This timing balances the benefits of restored nasal ventilation and drainage against the potential need for revision as the child grows.

Surgical Approach

The endonasal micro-endoscopic approach is the preferred method today, offering excellent visualization and magnification that results in increased safety and reduced surgical time. 1, 2

• The endonasal approach has evolved as the most common technique since the advent of endoscopic instrumentation 1
• The transpalatine approach should be reserved only for cases with insufficient endonasal visualization, as it is associated with long-term complications including palatal muscle dysfunction, mandibular joint pathology, and orthodontic problems in up to 50% of cases 2
• Historical approaches (transseptal, transantral) are rarely used today 1

Surgical Technique

Complete removal of the atretic plate with all bony and membranous components is necessary for success. 2

• Various instruments can be used including bougies, dissectors, biting and cutting instruments, drills, and lasers 1
• Mucosal flaps may be used to minimize raw opposing surfaces 1
• Topical application of Mitomycin C (0.4 mg/ml for 10 minutes) intraoperatively significantly reduces excessive granulation and scar formation 2

Critical Management Decision: Stenting

Postoperative stenting should be abandoned as it stimulates granulation formation that frequently leads to restenosis. 1

• Stenting is associated with a 35% failure rate compared to only 11% failure without stenting 1, 2
• This represents a clear evidence-based recommendation against routine stenting despite its historical use 1

Postoperative Management

Regular endoscopic controls combined with transnasal dilations using a soft rubber bougie are necessary for up to one year postoperatively. 1, 2

• Follow-up for at least one year is required to ensure stable patency 2
• Regular endoscopic examinations detect early signs of restenosis 2

Outcomes and Revision Surgery

The combination of endonasal micro-endoscopic approach with Mitomycin C application and postoperative dilations (without stenting) achieves the highest success rates. 1, 2

• In one series, none of the 5 cases treated with Mitomycin C and postoperative dilations required surgical revision 1
• Overall, 63% of patients require only one procedure, 24% require two interventions, and 7% require three procedures 2
• Restenosis due to granulation tissue formation is the most common complication, particularly when stents are used 2

Important Caveats

• Patients with CHARGE association or other syndromes require comprehensive evaluation for associated anomalies before and during surgical planning 2
• Careful assessment of facial nerve position is essential to avoid injury during surgery 2
• The created choanal opening will not increase in size with growth, which may necessitate revision in some cases 1
• Associated craniofacial deformities and skull base defects require individualized surgical planning based on detailed CT imaging 1