What is Microtia?
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.
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GRADE 1
Small, but almost normal ear
GRADE 2
Small ear with some recognizable anatomy, canal may be normal or small
GRADE 3
Small remnant of soft tissue with no ear canal
GRADE 4
No external ear and no ear canal
(Anotia)
GRADE 1
Small, but almost normal ear
GRADE 2
Small ear with some recognizable anatomy, canal may be normal or small
GRADE 3
Small remnant of soft tissue with no ear canal
GRADE 4
No external ear and no ear canal
(Anotia)
What we know about microtia
Microtia affects about one in every 6,000 to 12,000 babies worldwide
Microtia affects about 500 babies per year in the U.S.
Most common among Hispanic, Asian and Native American cultures
Seen in boys twice as often as girls
The right ear is affected twice as often as the left
About 10% of babies born with microtia have both ears affected (“bilateral microtia”)
Microtia is often associated with aural atresia (a missing ear canal)
More than 90% of children with microtia and atresia have a conductive hearing loss
What we don’t know about microtia
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.
What we don’t know about microtia
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
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.
Hemifacial Microsomia
Goldenhar Syndrome / OAVS
Treacher Collins Syndrome