Microtia is a rare congenital deformity that occurs when the outer part of the ear, called the external ear or pinna, does not fully develop in utero. Children with microtia are born with small, narrow, irregularly shaped ears. One or both ears may appear malformed around the outer ear, ranging from a very slight degree to complete absence of the outer ear, a condition called anotia. When an individual has microtia, the ear canal also appears very narrow, or is completely absent, resulting in a significant decrease in the ability to hear.
Microtia is usually diagnosed by doing a physical examination on the child when they are born. This condition affects approximately one in 8,000 to 10,000 children in the United States every year, occurring in males more than females. However, microtia’s effect on children is diverse, as it also affects newborns in other countries, with Asian, Central and South American regions having the highest prevalence.
90 percent of the children affected are born with unilateral microtia, meaning either the right or left has some form of deformity, with the right ear usually worse than the left. However, microtia can also occur bilaterally, where both ears are affected. Bilateral microtia occurs in approximately one out of 25,000 births. There are four grades of this condition, demonstrating the changes or stages that occur as the condition progresses.
Grade 1: The outer part of the ear (external ear) is small but developed somewhat normally. The ear canal often becomes narrow (canal or aural atresia) or is missing completely (canal stenosis).
Grade 2: The outer part of the ear is abnormally developed, mainly the upper part. The ear canal is also narrow and can be closed at this stage.
Grade 3: The ear is small, with the skin and cartilage being abnormally shaped. There is no ear canal. This grade is the most common form of microtia.
Grade 4: During stage 4 microtia, the ear and its structure is gone. Skin tags are often present.
Microtia is not a life-threatening condition, but due to the aesthetic deformities that this condition reveals, it can significantly impact one’s hearing and can mentally and physically take a toll on a child’s confidence and self-esteem (due to the appearance of their ears). Diminished hearing can cause trouble in social settings, such as school, and lead to the impairment of one’s speech.