Microtia is a congenital deformity affecting the outer ear (pinna) where the ear does not fully develop during the first trimester of pregnancy. A Microtia ear is often smaller in size, can have a peanut shaped appearance, only have a small nub or lobe present, or be completely absent at birth. Microtia is Latin for the words micro and otia, meaning “little ear.” Microtia can affect one ear (unilaterally) or both ears (bilaterally). Microtia occurs in every 1 out of 6,000 to 12,000 births. The right ear is more commonly affected. Microtia is often accompanied by Atresia.
Atresia (Aural atresia)
It is the absence or closure of the external auditory ear canal. The malformation of the middle ear bones (incus, stapes, and malleus) may be affected including the narrowing of the ear canal, known as canal stenosis. Atresia is Latin for absence of an opening.
Aural atresia usually involves only one ear (unilateral atresia) and occurs in 1 in 10,000 to 20,000 births. Bilateral atresia, when both ears are affected, is much more rare. Children with aural atresia and one normal hearing ear may develop normal speech but have trouble knowing where sound comes from, referred to as “sound localization.” Regular appointments with an audiologist are important to confirm the child's hearing isn’t changing in either ear. Babies with bilateral atresia have significant hearing loss. Doctors recommend new-borns use hearing aids to help develop speech and language.
Grades of Microtia
Microtia looks different for every child. Some babies with Microtia are born with a slightly smaller ear, while others have no ear (anotia).
The most commonly used grading system to describe Microtia is shown below. The grade increases from 1 to 4 based on the severity of the condition.
In most cases the cause of Microtia CANNOT be determined. It is thought that Microtia may occur due to a combination of environmental, genetic and other factors.
It is important to understand that even though so many parents feel guilty that their baby was born with a birth defect, nothing a mother did during pregnancy caused the Microtia.
Rarely, a single gene abnormality can cause Microtia, as can exposure to a medicine called isotretinoin (Accutane®) during pregnancy.
Recently the CDC found an increased risk for Microtia in mothers who were diabetic before they became pregnant.
Syndromes associated with Microtia
While Microtia is often seen as an isolated condition, it may also occur with a syndrome. Syndromes associated with Microtia can also affect the kidneys, heart, eyes, craniofacial bones, and skeletal system. These children are often cared for by a Craniofacial Team.
Treacher Collins Syndrome
Effects of Microtia
- Most parents experience guilt, they think they must have done something wrong during pregnancy.
- Frustration due to lack of support and information about the condition
- Worry about how their children will cope, especially when it’s time to go to school.
On Children: Many children face the following:
- Can make your child feel self-conscious
- Being targets of cruel taunting
- Unwelcome stares from other children and even adults, who are not familiar with the defect.
- Difficulty in hearing, which affects proper speech development
- Hurt their academic perfomance
- Low Self Esteem and other emotional problems.