Affecting about 1 to 5 of every 10,000 babies born globally, microtia is a rare disorder encompassing a spectrum of congenital ear malformations or even absence of the auricle, the visible part of the external outer ear. An infant born with microtia has a small protrusion or nub that pokes out where a fully formed ear usually develops.
Microtia is often accompanied by hearing loss, ear infection, and cosmetic issues that may affect the overall appearance of an individual and their self-confidence.
Causes and Risk Factors
Although there is no specific reason for congenital ear deformity and most of the time, a cause can't be identified, lack of blood supply during fetal development, medication intake, and genetic modification are considered reasons responsible for microtia and other congenital ear deformities. An accident or traumatic event during pregnancy can also result in microtia in a developing fetus.
Diagnosis
If microtia appears in only one ear, the diagnosis is called unilateral microtia, while in both ears, it's known as bilateral microtia. Generally affecting boys, microtia can run in families but can skip generations. Children with this condition often have some hearing loss in the affected ear, making it harder for them to learn to speak. Surgery can help improve hearing and the appearance of the ear.
Your child's pediatrician will want to see how well your child can hear. An auditory brainstem response test is often used for children with microtia. An audiologist will put small stickers, called electrodes, near your child's ears and on their forehead. Clicking sounds and tones go through the earphones, and electrodes measure how the hearing nerves and brain respond to the sounds.
The test isn't painful, but your child will need to be still during the procedure. If they're younger than 6 months, the audiologist can do the test while they're napping. If they're between 6 months and 7 years old, the procedure might be done with sedation so your child will stay completely still and quiet during the test.
Treatment Options
If your child has mild microtia and no hearing loss, they may not need any treatment. Kids with more severe problems might need surgery to fix the affected ear.
Surgery can help with hearing if your child has conductive hearing loss in which sound can't travel from the outer ear to the inner ear. Doctors usually wait to perform surgery when the child reaches the age of 9 or older because they have more cartilage that can be used for ear reconstruction. A small number of children with microtia have sensorineural hearing loss, which is usually permanent and can happen when tiny hairs that carry sound from the inner ear to the brain are damaged.
Your doctor may discuss the following surgical options with you:
- Autologous costal graft surgery: In this traditional surgical reconstruction, the surgeon creates a new ear with a piece of cartilage taken from the child's rib cage.
- MEDPOR® graft surgery: This surgery uses a synthetic material instead of rib cartilage. The surgeon will cover the implant with tissue from your child's scalp during a single surgery when your child is as young as 3 years old.
- Prosthetics: A specialist can make a natural-looking prosthetic ear that your child will wear with an adhesive or attached to an anchor system, which requires minor surgery.
Treatment options for hearing loss include hearing aids and speech therapy. Whether it's worn or implanted, a hearing aid can improve your child's hearing and help them with speech and language acquisition.
With hearing improvements and surgical interventions, many children with microtia can have otherwise normal development and lead active and healthy lives.