An incidental case of bilateral choanal atresia

Patient history:

18 years old male

Bilateral nasal obstruction since childhood ++

Right sided nasal discharge since childhood ++

Clinical examination:

Deviated septum to left ++

Right inferior turbinate hypertrophy ++

Imaging:

CT scan PNS plain coronal cuts showed:

DNS

Rt inferior turbinate hypertrophy

There was no evidence of sinusitis

Choanal atresia could not be made out ? missed out in the cuts i.e. 5 mm cuts

DNE showed:

DSL with inferior turbinate hypertrophy

Choanal atresia on both sides

Endoscopic examination

Treatment:

Septal correction with transnasal repair of choanal atresia was performed Atretic bony plate was drilled out and the recreated choana was stented.

Post op management:

Stent was left in place for 6 weeks.

Regular nasal douching and suction clearance was done.

Discussion:

During the third week of IU life the nasal placodes starts to invaginate forming nasal pits.

These pits burrow into the surrounding mesenchyme forming nasal pouches.

Formation of bucconasal membrane occurs at this point.

Pathogenesis:

Choanal atresia could be caused by persistent bucconasal membrane / faulty mesodermal migration.

Boundaries of atretic plate:

Superior - sphenoid

Lateral - Medial pterygoid lamina

Medial - vomer

Inferior - Horizontal plate of palatine bone

CT scan features suggestive of choanal atresia:

Choanal air space measurement:

Mean normal - 0.67

Mixed atresia - 1/3 of normal

Bony atresia - 0

Mean width of vomer:

Mean - 0.23

Bony atresia - 0.6

Membranous atresia -0.3

CT scan showing choanal atresia

Possible surgical approaches:

Transnasal

Transpalatal

Trans septal

Syndromes associated with choanal atresia:

CHARGE

Treacher Collins

Crouzans