Congenital ENT problems

Congenital problems affecting the ear, nose and throat are relatively common and range in severity and impact. Some, such as cleft palate, are commonly detected at antenatal scanning whilst others present at birth or subsequently.

Incidence suggested as <5/10,000 births each for the ear, eye and throat.¹

The ear forms into one anatomical unit serving our senses of hearing and balance. However, embryologically the external, middle and inner ears have separate origins. Failure of any of these elements will result in congenital abnormality.

External ear

Abnormalities occur in about 1% of infants.
Look for:

• Low setting of ears (where the upper border of the ears falls below a line drawn from the outer canthus of the eye to the external occipital protuberance) - associated with Down's syndrome.
• Absent or rudimentary pinnas (microtia) - may be associated with deafness and certain syndromes (e.g. Goldenhar and Treacher-Collins). Their appearance may be improved by cosmetic surgery or prostheses.
• Auricular pits or sinuses - caused by the failure of the obliteration of the first branchial cleft. They are usually found in front of the helix or tragus. They occur in about 8/1000 and can act as a site of infection, so may require excision.
• Accessory auricles - these look like skin tags and occur adjacent to a normally placed pinna. They can be removed by simple ligation or plastic surgery.
  

  Note, auricular pits and tags may indicate the presence of sensorineural or conductive deafness so careful hearing testing is required, but are frequently of no other significance.

• Prominent, bat or ‘lop’ ear – do not cause functional impairment, but are frequently the cause of teasing and emotional problems in older children and of concern to parents. Their appearance can be improved soon after birth nonsurgically, using moulding splints and steristrips² or by pinnaplasty in older children.³
• External auditory canal stenosis - this often occurs with other malformations of the auricle and middle ear. Microtia and temporal bone malformation, causing stenosis or atresia, can be associated.⁴ In Down's syndrome, ear canals are often narrow. In mild cases, surgical enlargement is not usually necessary unless otitis externa or wax impaction becomes a problem. In full atresia, reconstructive surgery of the external ear canal and middle ear is indicated for children >5 years age with bilateral malformation causing significant hearing loss. In the interim, patients should wear bone conduction hearing aids.

Middle ear

• Ossicular chain defects often occur in conjunction with atresia of the external ear canal, as mentioned. Treacher-Collins syndrome consists of middle and external ear malformation with abnormal facial bone development.
• Congenital cholesteatoma - these are rare and are thought to arise due to trapping of squamous epithelium within the temporal bone during embryogenesis. They cause progressive conductive hearing loss. 80% occur in anterior-superior part of the middle ear, appearing as white-cyst like structure within an intact tympanic membrane. Management is surgical.⁵

Inner ear

• Defects of the inner ear usually result in severe sensorineural (SN) deafness. Up to 20% of children with SN hearing loss are found to have congenital defects on CT or MRI. Congenital deafness can be hereditary, but normal inner ear development is also very sensitive to interruption by environmental factors such as Rubella virus in the 7th-8th weeks of fetal development. Cochlear implants may be feasible and successful in a subset of those with malformed cochlea, although surgery is more technically difficult.⁶

The development of the nose is highly complicated, involving the fusion of facial and nasal prominences and the invagination of the nasal pit to ultimately form the choanae. A cartilaginous and bony framework of the nose follows.
Look for:

• Absent nasal bones or even the nose itself (arhinia), usually as part of a syndrome of abnormalities.
• Accessory nostrils and Proboscis lateralis (or congenital tubular nose) where the external nose fails to develop on one side.
• Choanal atresia is the commonest congenital abnormality of the nose (1/7000 live births) with a unilateral or bilateral bony (90%) or membranous(10%) septum between the nose and the pharynx. It is frequently associated with the CHARGE syndrome of:
  • Coloboma
  • Heart disease
  • Atresia choanae
  • Retarded growth in development and/or CNS abnormalities
  • Genital abnormalities and/or hypogonadism
  • Ear abnormalities and/or deafness
  If unilateral, the infant may be asymptomatic until experiencing its first respiratory infection when unilateral nasal discharge or very severe obstruction suggests diagnosis. The child may also experience increased difficulty breathing whilst feeding or crying. Bilateral obstruction tends to present with respiratory distress at birth. The diagnosis should be suspected when an appropriately sized nasal catheter cannot be passed into the pharynx. Airways support is required and surgical repair, when appropriate. Many different surgical techniques have been used to correct the abnormality.⁸
• Congenital masses, the most common of which are nasal dermoids. These tend to occur in the midline, presenting either as nasal masses or fistulae, often in the first year of life. Treatment is by surgical excision.
• Encephaloceles are a herniation of neural material though a skull defect. They can occur through the nose. Evaluate with CT or MRI. Do not biopsy.

Cleft lip and palate⁹

This has been a relatively common congenital abnormality, occurring in about 1/600 births. About a third involve the palate only. Family history occurs in about a third of cases, with risk of recurrence in a sibling of about 1 in 25 and risk in the child of a parent with a cleft of 1 in 8.¹⁰ It occurs due to failed fusion of the the facial processes between the 5th and 12th weeks of fetal development. Severity varies between a notch in the upper lip or bifid uvula to bilateral clefting of the lip and palate.

Larynx¹¹

The inner lining of the larynx is of endodermal origin, but the cartilages and muscle originate from the mesenchyme of the 4th and 6th branchial arches.
Congenital abnormalities include:

• Complete atresia of the larynx – very rare but lethal. This presents as acute respiratory distress on cord-clamping. The baby will make great respiratory effort but be unable to breathe or cry. Occasionally infants are saved by tracheostomy immediately after birth.
• Laryngeal webs – these represent a milder form of the failure of recanalisation of the laryngotracheal tube, compared to complete atresia. They tend to occur between the vocal cords. The size of the web will determine the degree of symptoms - if complete or nearly complete, the infant will have significant airways obstruction, presenting with respiratory distress, severe stridor and a weak, abnormal cry. Often obstruction is incomplete with only mild stridor and dyspnoea. Management will involve airways support and lysis or stenting of the web. About a third of children with laryngeal webs have other abnormalities of their respiratory tract, most commonly subglottic stenosis.
• Congenital laryngeal stridor – where stridor appears or lasts more than a few days after birth, it is usually due to lesions in or near to the larynx. Laryngomalacia (floppy arytenoid cartilage) is the commoner cause and usually presents with noisy, crowing respiratory sounds and stridor. Signs are usually absent at birth, but become apparent over the first few weeks and may persist up to 2 years. It is usual to confirm the diagnosis with laryngoscopy but normally requires no treatment and will resolve spontaneously. Feeding difficulties can be overcome with slow feeding using a small nipple or dropper or occasionally a gavage. The prone position may also help to control symptoms.
• Vocal fold paralysis - this is the second most common cause of congenital laryngeal stridor. Most cases are idiopathic, but some may be secondary to other CNS lesions such as hydrocephalus, cerebral palsy or following birth trauma. Tracheotomy is usual with bilateral fold paralysis but spontaneous recovery occurs in over 50%.