Hemifacial Microsomia

Hemifacial microsomia is a condition in which the tissue on one side of the face is underdeveloped, usually affecting the ear, mouth and jaw. Sometimes, both sides of the face can be affected and may involve the skull as well as the face.

Hemifacial microsomia has various forms and depending on other concurrent conditions may be called Goldenhar syndrome, brachial arch syndrome, facio-auriculo-vertebral syndrome, oculo-auriculo-vertebral spectrum or lateral facial dysplasia.

What are the different types of hemifacial microsomia?

The deformity in hemifacial microsomia varies from mild to severe. In the more severe cases, the following areas are underdeveloped:

•    External and middle ear
•    Side of the skull
•    Thickness of the cheek tissue
•    Upper and lower jaws
•    teeth
•    Some nerves that allow facial movement

In the milder forms, only some structures are affected and to a lesser degree.

What causes hemifacial microsomia?

Hemifacial microsomia usually occurs by chance, but is thought to be inherited in some circumstances.

Which parts of the facial bone are involved?

One of the most obvious problems in hemifacial microsomia is the underdevelopment of the upper and lower jaw on the affected side. Your child’s mouth may appear to slant upward toward one side. Often the forehead and cheek are flattened on one side, with one eye socket smaller than normal.

Other areas of your child’s face that may be affected include:

•    Your child may have unequal cheek fullness because of the underdeveloped fat and muscle. Some parts of the face may not move normally, which may cause a crooked smile.

•    Your child may have a misshapen ear or almost complete absence of the external ear. Small tags of skin may also be present in front of the ear.

What is the treatment for hemifacial microsomia?

After a diagnostic evaluation and meeting with a craniofacial team, the following treatment options may be considered at various times in your child’s life:

•    Jaw surgery
•    Ear reconstruction
•    Facial nerve and muscle reconstruction
•    Skin tag excision
•    Hearing aid placement