75 Paediatric Nasal Obstruction
Neonates and young children presenting with nasal obstruction are common in general practice and paediatric ENT clinics. A key point to consider is that neonatal rhinitis can mimic choanal atresia. Choanal atresia is a neonatal emergency and transfer for surgery should be arranged as soon as possible following diagnosis. Assessment with endoscopy using the 120-degree Hopkins rod has transformed the management of choanal atresia. Remember that some nasal masses may have an intra-cranial origin, so high-quality imaging should be requested. It is important to think of cystic fibrosis if presented with a child with nasal polyps. Beware angiofibroma in adolescent boys. These are important clinical precepts, and they are essential edicts for the examination.
75.1 Causes of Nasal Obstruction in the Newborn
• Rhinitis (common).
• Choanal atresia/pyriform aperture stenosis.
• Nasal/pharyngeal masses.
75.2 Causes of Nasal Obstruction in Older Children
• Nasal polyps (consider cystic fibrosis).
• Osseocartilaginous deformity.
• Foreign body.
• Nasal masses.
• Fibrous dysplasia.
• Angiofibroma (adolescent boys).
75.3 Neonatal Rhinitis
Neonatal rhinitis is fairly common and can mimic choanal atresia. Treatment is expectant and mostly the condition is short-lived. Saline nose drops and in severe cases a short course of intra-nasal steroids will hasten resolution.
75.4 Choanal Atresia
Congenital choanal atresia is due to the embryological failure of the primitive bucconasal membrane to rupture before birth. This results in the persistence of either a bony plate (90%), a fibrous membrane or both, obstructing the choana. It occurs in about 1 in 10,000 births. Unilateral choanal atresia is twice as common as bilateral. Bilateral choanal atresia may cause respiratory distress and if not recognised, respiratory arrest and death shortly after birth. The choana means the posterior opening of the nose and therefore the frequent description of the choana as the ‘posterior choana’ when describing the posterior opening is incorrect.
The mouth, palate, nose and paranasal sinuses develop from the cranial portion of the primitive foregut. The nose begins as two epithelial thickenings known as the nasal placodes, which appear above the stomatodeum about the fourth week in utero. The placodes deepen to form olfactory pits which lie between the medial and lateral nasal processes. The medial processes fuse to form the frontonasal process. This is compressed to form the nasal septum as the lateral nasal processes approach each other. The nasal septum will then grow posteriorly to divide the two nasal cavities. Each nasal cavity is closed posteriorly by the thinned out posterior wall of the nasal sac, called the bucconasal membrane. This usually breaks down around the sixth week in utero. Its persistence is thought to be the cause of choanal atresia.
75.6 Clinical Features
A unilateral obstruction may be asymptomatic at birth but will later cause unilateral nasal discharge and obstruction. Examination of the nose will show thick gelatinous secretions on the affected side, and no airway can be demonstrated when holding a cold-plated spatula below the nares. Only the patent side will steam the surface (mirror test). A unilateral choanal atresia may be treated electively and indeed some are only diagnosed after some years when a parent and/or GP becomes fed up with the child having a unilateral nasal discharge that does not respond to repeated courses of antibiotics and nasal decongestants.