OVERVIEW

What is congenital atresia of the external auditory canal?

Congenital atresia of the external auditory canal refers to the narrowing or complete closure of the external auditory canal caused by developmental abnormalities of the first branchial groove during embryonic development. It rarely occurs alone and is often accompanied by malformations of the auricle, middle ear, or tympanic membrane.

Children with ear canal atresia frequently exhibit abnormalities in the auditory ossicles, particularly fusion between the ossicles or fusion with the bony atresia in the ear canal. Congenital external auditory canal atresia can occur unilaterally or bilaterally, with a ratio of approximately 4:1.

Note: The external auditory canal is the passage connecting the external ear opening to the tympanic membrane, commonly known as the ear canal where earwax accumulates. The outer one-third is cartilaginous, while the inner two-thirds is bony.

Is congenital atresia of the external auditory canal common?

It is relatively common, with an incidence rate of approximately 0.5 to 1 per 10,000 individuals, and there is no significant difference between males and females.

SYMPTOMS

What are the manifestations of congenital aural atresia?

It is usually accompanied by auricular deformity, with or without middle ear deformity. Based on severity, it can be classified as mild, moderate, or severe:

• Mild: Slight auricular deformity, relatively normal shape of the cartilaginous segment at the external end of the ear canal, but the deep part may be narrow or completely occluded. The bony segment is almost occluded, while the inner ear is mostly normally developed, with no significant hearing loss. This type is less common clinically than the moderate form, accounting for about half of its frequency.

• Moderate: Obvious auricular deformity, almost complete occlusion of the ear canal, varying degrees of middle ear dysplasia, and hearing impairment (conductive hearing loss, caused by the inability of sound to properly transmit to the inner ear). This is the most common type clinically.

• Severe: Incomplete auricular morphology, sometimes appearing as only a small protrusion, complete occlusion of the ear canal, significant middle ear abnormalities, and even inner ear dysplasia, leading to possible hearing loss. This is the least common type clinically.

What are the complications of congenital aural atresia?

Many children with aural atresia have normal middle ears but may develop complications such as acute otitis media (middle ear infection caused by bacteria) and cholesteatoma (an abnormal accumulation of keratin-producing squamous epithelium forming a mass). Symptoms include ear pain and fever. Imaging tests like CT or MRI can aid in diagnosis.

CAUSES

What are the causes of congenital aural atresia?

Congenital aural atresia may occur due to familial inheritance, or it may result from certain diseases (such as rubella, influenza, Japanese encephalitis, syphilis, hypothyroidism, etc.) or improper medication use (such as streptomycin, gentamicin, quinine, furosemide, etc.) during the fetal ear development period (3 to 7 months of pregnancy), leading to abnormal ear canal development.

DIAGNOSIS

How to Diagnose Congenital Aural Atresia?

Doctors typically diagnose it based on abnormal responses to sound stimuli in infants, combined with otoscopy, auditory function tests, and imaging studies, after ruling out other conditions.

What Tests Are Needed for Congenital Aural Atresia? Why Are These Tests Performed?

Congenital aural atresia requires comprehensive examinations to assess severity, guide treatment planning, and exclude other conditions:

• Medical History and Physical Examination: Records abnormal responses from birth to consultation to preliminarily evaluate hearing loss. Ear examinations assess the degree of auricular and ear canal deformities.

• Otoscopy: A funnel-shaped device inserted into the ear canal to observe its structure up to the eardrum, determining the extent of stenosis or occlusion.

• Auditory Function Tests: Include tuning fork tests, pure-tone audiometry, evoked response audiometry, otoacoustic emissions, and tympanometry to evaluate hearing impairment, confirm conductive hearing loss, and determine surgical indications.

• Imaging Studies: CT or MRI scans of the ear help identify the location, scope, and severity of the abnormality.

What Conditions Should Congenital Aural Atresia Be Distinguished From?

It must be differentiated from other congenital ear malformations, such as isolated middle ear deformities, inner ear deformities causing conductive hearing loss, or congenital sensorineural hearing loss. Auditory function tests and imaging studies aid in differentiation.

TREATMENT

Which department should I visit for congenital aural atresia?

Otolaryngology (ENT).

Does congenital aural atresia require hospitalization?

Hospitalization is usually required for surgical treatment. If there are no immediate surgical indications, outpatient follow-up is recommended.

How is congenital aural atresia treated?

The primary goals of treatment are to improve hearing and/or appearance, with surgery being the main approach:

• For unilateral cases with acceptable auricle morphology and normal hearing in the contralateral ear, surgery may be deferred with regular monitoring.

• The use of bone conduction/bone-anchored hearing aids (surgically implanted titanium devices that bypass the external/middle ear) remains controversial and requires comprehensive evaluation.

• Bilateral cases require early intervention, ideally within weeks of birth, using bone conduction hearing aids to prevent speech development delays.

• Surgical reconstruction (canalplasty/tympanoplasty) is typically performed at preschool age (4-6 years) when mastoid development permits. Auricular reconstruction may be performed concurrently or staged.

• For significant unilateral deformities with normal contralateral ear, surgery around age 10 is recommended. Procedures carry risks of facial nerve injury and require experienced otologists with intraoperative neuromonitoring.

DIET & LIFESTYLE

What should patients with congenital aural atresia pay attention to in their diet?

There are no special dietary requirements, but attention should be paid to balanced nutrition and foods rich in vitamins.

What should patients with congenital aural atresia pay attention to in daily life?

• Observe the child's response to sounds.

• For children wearing hearing aids, ensure proper care to avoid accidental detachment due to improper handling.

• For children who have undergone corrective surgery, lifelong cleaning and care of the new ear canal are necessary.

• If symptoms such as ear pain or fever occur, complications should be considered, and medical attention should be sought promptly.

Is follow-up required for congenital aural atresia?

Yes, regular outpatient follow-ups are needed, including otoscopy and hearing function monitoring.

PREVENTION

Can congenital aural atresia be prevented?

• Congenital aural atresia can be prevented by promoting eugenics knowledge, strengthening premarital genetic testing, and prohibiting consanguineous marriages;

• Enhance pregnancy protection, avoid medication or use drugs under medical supervision, and refrain from using medications that may affect ear development;

• Conduct prenatal diagnosis and selective pregnancy termination to reduce incidence rates;

• Early detection, diagnosis, and treatment can mitigate the disease's impact on children's hearing and language development and reduce complications.