Congenital ear deformity means an ear deformity that a child was born with. In some cases these deformities can cause hearing loss, and they can also be embarrassing for children, so early intervention is important.
There are two types of congenital ear deformity:
Microtia – this is abnormal growth of the external ear. Microtia occurs more often in boys than in girls and occurs in about one in every 6,000 to 12,000 births. It is more likely to occur on the right side. Although there is hearing loss in children with microtia, the inner ear canal is usually normal.
Microtia can range in severity from a minor ear fold to a marked absence of ear development, where a small tag of skin and cartilage are the only signs of an external ear. These are the three types of Microtia
- Grade 1, in which the ear is smaller than normal, but has many of the same features as a normal ear. The child may or may not have hearing loss.
- Grade 2, in which the normal features of the ear are missing, but there may be an ear lobe and a sausage-shaped remnant of skin where the outside edge of the ear would normally be.
- Grade 3, in which the ear consists of a vertical skin appendage with a malformed lobe at the end. Usually there is no external ear canal in children with Grade 3 Microtia.
Atresia – this is a complete absence of the external ear canal, which is almost always accompanied by abnormalities of the middle ear bones, as well as the external ear.
Children can suffer from one of these types of congenital ear deformities, or both may be present at the same time. Also, these two conditions can occur in one or both ears.
Although the exact cause of Microtia and Atresia is not known, some theories point to chromosomal abnormalities, heredity (or inherited), or side effects from medications like thalidomide or isotretinoin (also known as Accutane). In some cases Microtia and Atresia are associated with Goldenhar syndrome and Treacher syndrome.
Diagnosing Microtia and Atresia
Microtia and Atresia can typically be seen immediately at birth. Depending on the amount and structure of tissue present the condition will fall into one of several categories, and will range from a slightly malformed or undersized outer ear, to a sausage-shaped skin remnant or no ear at all.
Diagnosis of Microtia and/or Atresia is followed by a hearing evaluation to determine the amount of hearing loss, if any.
Other tests may occur as the child grows and prior to any reconstructive surgery that may be required. These include:
- Frequent hearing evaluations to rule out other possible problems
- An auditory brainstem response test
- A CT scan of the ears, a multi-dimensional x-ray that allows the doctor to see the ear anatomy from many angles and will show any fluid in the ear; a CT scan is typically performed around age six.
Treatment for Microtia and Atresia
Shriners Hospitals for Children® offer treatment for Microtia and Atresia that may be as simple as a hearing aid or as extensive as a complete ear construction.
Here are some examples of treatments offered:
Hearing aids – these may be worn on one or both ears and should be fitted immediately after birth for children who have hearing loss
Total external ear reconstruction – this process requires three to four separate surgeries with an interval of about three months in between. The process may take longer if the child has Microtia/Atresia in both ears. Typical ear reconstruction follows these four phases:
- First stage – rib cartilage is harvested and sculpted into the shape of the ear, then placed under the skin pocket of the skin that exists on the outside.
- Second stage – the earlobe is formed.
- Third stage – the ear is elevated by a skin graft performed on the “back” of the new ear.
- Fourth stage – the cartilage “bump” in front of the ear canal is formed, and the curved inside of the ear is shaped.