Microtia is a congenital deformity affecting the development of the outer ear. The severity of this condition varies, but it can significantly impact hearing and facial symmetry. Thus, early diagnosis and intervention are paramount in managing its effects.

What is Paediatric Microtia?

Paediatric Microtia is a congenital condition where a child is born with an underdeveloped or missing outer ear (pinna), which may affect hearing and facial symmetry. It can occur in one ear (unilateral microtia) or both ears (bilateral microtia) and is often associated with aural atresia (absence of the ear canal).

This condition varies in severity and is classified into four grades:

• Grade 1 (Mild): A slightly smaller ear with most structures intact.
• Grade 2: A partially formed ear with some missing parts.
• Grade 3: A small, peanut-shaped remnant with no ear canal (atresia).
• Grade 4: Complete absence of the ear (anotia).

Grade 1 microtia is the mildest form and often does not significantly impact hearing. However, in more severe cases, children may experience conductive hearing loss due to the absence of an ear canal.

Is Microtia a Disability?

One of the most common concerns among parents is whether microtia is considered a disability. The answer depends on the severity and its impact on hearing.

• Mild cases (Grade 1 Microtia): Children may have normal or slightly reduced hearing and do not typically require major interventions.
• Moderate to severe cases: If microtia is accompanied by aural atresia (absence of an ear canal), it can lead to significant hearing impairment. In such cases, assistive devices or surgical treatments may be necessary.

In many countries, microtia is not classified as a disability unless it significantly impairs hearing and communication. However, children with severe hearing loss may qualify for special support services in school.

Paediatric Microtia Causes: Why Does It Happen?

The exact cause of microtia isn’t always clear, but several factors may contribute to its development:

Genetic Factors

In certain instances, microtia can be hereditary, indicating a potential genetic connection. Specific gene mutations or inherited conditions may elevate the likelihood of developing this condition.

Environmental Factors

Exposure to harmful substances during pregnancy, such as:

• Certain medications (e.g., isotretinoin used for acne treatment)
• Alcohol and drug use
• Poor maternal nutrition
• Exposure to high levels of pollution or toxins

Vascular Disruptions

A major cause of microtia is nutrient interruptions in early pregnancy. Expectant mothers should maintain a healthy diet to reduce the risk of this congenital deformity.

Syndromes Associated with Microtia

Microtia is sometimes linked to genetic syndromes, such as:

• Treacher Collins Syndrome
• Goldenhar Syndrome
• Hemifacial Microsomia

We have discussed more about these conditions in a later segment.

Spontaneous Occurrence

Many cases of microtia occur randomly without any identifiable cause. It is not typically preventable and can happen even in healthy pregnancies.

Is Paediatric Microtia Hereditary?

Microtia is usually a sporadic condition, meaning it occurs without a clear family history. However, in some cases, it may be inherited. Studies suggest that about 5-10% of microtia cases have a genetic component.

Certain inherited syndromes, such as Treacher Collins Syndrome and Goldenhar Syndrome, can include microtia as one of their features. If there is a family history of microtia or related conditions, genetic counselling can help assess the risk of recurrence in future pregnancies.

How Does Microtia Affect Hearing?

Microtia primarily affects hearing due to its impact on the external and middle ear structures. The severity of hearing loss depends on the degree of ear malformation and whether one or both ears are affected.

Conductive Hearing Loss

Microtia is often associated with atresia, a condition where the ear canal is either completely absent or abnormally narrow. This prevents sound waves from reaching the middle and inner ear properly, leading to conductive hearing loss.

• Mild to Moderate Hearing Loss: If the ear canal is partially formed.
• Severe Hearing Loss: If the ear canal is completely closed (aural atresia).

Unilateral vs. Bilateral Hearing Loss

• Unilateral Microtia (One Ear Affected): Children can still develop normal speech and language skills since the other ear provides adequate hearing. However, they may struggle with sound localisation and hearing in noisy environments.
• Bilateral Microtia (Both Ears Affected): More significant hearing loss, which can impact speech and language development if not managed early.

Inner Ear Functionality

In most cases, the inner ear (cochlea) functions normally, meaning the auditory nerve can still process sound if properly transmitted. This is why bone-conduction hearing aids or implantable devices can be effective treatments.

Effects on Speech & Learning

Children with untreated hearing loss may face speech delays, difficulty distinguishing sounds, and challenges in school settings. Early intervention with hearing aids, speech therapy, and assistive listening devices can help minimise these effects.

Treatment Options for Paediatric Microtia

Let’s talk solutions now. The treatment of microtia depends on the severity of the ear deformity, the presence of hearing loss, and the child’s overall health. While some children with mild microtia may not require intervention, others may benefit from reconstructive surgery, hearing devices, or both.

Hearing Rehabilitation

Since microtia is often associated with conductive hearing loss, early intervention is crucial for speech and language development.

• Bone Conduction Hearing Aids: This device helps children with aural atresia by transmitting sound through bone vibrations to the inner ear. It can be worn with a soft headband for young children or as a bone-anchored implant after age 5.
• Bone-Anchored Hearing System (BAHS) / Bone-Anchored Hearing Aid (BAHA): A surgically implanted device that stimulates the inner ear through bone conduction is often recommended for children diagnosed with bilateral microtia and atresia.

Surgical Reconstruction of the Outer Ear

Reconstructive surgery is an option for improving cosmetic appearance and, in some cases, enhancing hearing. It is usually performed after age 6-10 when the ear has grown sufficiently.

• Rib Cartilage Reconstruction: This procedure involves using the child’s own rib cartilage to create a new ear, typically done in multiple stages over several months. The pros include natural-looking and long-lasting results, but the cons include the need for multiple surgeries and potential rib discomfort.
• Medpor (Synthetic Ear Implant) Reconstruction: In this procedure a porous polyethylene implant covered with the patient’s skin is used. It is typically done in one or two stages and requires fewer surgeries than rib cartilage. It is suitable for younger children, but there is a risk of infection or implant rejection.
• Ear Prosthesis (Silicone Ear): This is a custom-made prosthetic ear that can be attached with adhesive or implants. Pros include a non-surgical and realistic appearance, but cons include the need for regular maintenance and replacements.

Ear Canal Reconstruction (Atresiaplasty)

Surgery to create an ear canal and eardrum is typically recommended for children who have well-developed middle ear structures. The success rate of this procedure can vary, and in some cases, hearing aids may still be required post-surgery.

Speech & Audiology Support

Regular hearing tests and speech therapy are essential for promoting language development. Additionally, classroom accommodations such as FM systems can greatly enhance sound perception in noisy environments. These interventions play a crucial role in supporting individuals with hearing impairments to effectively communicate and engage in educational settings.

Psychosocial Impact of Microtia

Microtia can affect a child’s self-esteem, social interactions, and emotional well-being, especially as they grow and become more aware of their appearance and hearing challenges.

Self-Esteem & Body Image

Children with microtia may feel self-conscious about their appearance, especially during school years when they may face teasing. However, having a supportive family and peer environment can help them build confidence.

Social & Emotional Challenges

Group conversations can be challenging for people with hearing loss, leading to frustration and potential for bullying or social exclusion which can cause emotional distress. Encouraging open discussions and practising social skills can help improve coping mechanisms in these situations.

Speech & Academic Development

Hearing loss can cause problems with speech development and communication, as well as difficulties in the classroom. Early intervention with speech therapy and hearing devices can make a positive difference.

Family & Caregiver Impact

Parents may experience stress and guilt regarding their child’s well-being as a result of microtia. Engaging with support groups and seeking emotional support can help address these emotions.

Psychological Support & Coping Strategies

Counselling and peer support groups play a crucial role in assisting children who struggle with self-image issues by providing them with a sense of community and fostering a positive and resilient mindset. These resources offer a safe space for children to connect with others who may be facing similar challenges, ultimately helping them build confidence and develop coping strategies.

Sources:

• https://www.childrensnational.org/get-care/health-library/microtia
• https://www.stanfordchildrens.org/en/services/microtia/faq
• https://lewinear.com/psychological-effects
• https://www.stanfordchildrens.org/en/services/microtia/treatment
• https://www.cincinnatichildrens.org/health/m/microtia
• https://my.clevelandclinic.org/health/diseases/microtia
• https://drpanossian.com/blog/how-microtia-atresia-affects-hearing-and-speech-in-children/