Genetics Northern California

Oculo-auricular-vertebral spectrum

Both hemifacial microsomia and Goldenhar syndrome are conditions within the oculo-auriculo-vertebral spectrum (OAV). These conditions primarily affect ear, mouth and jaw development, although other anatomical structures may also be affected, such as the spine.

  • Hemifacial microsomia: In hemifacial microsomia, the ear, and the jaw (most often the lower jaw) is underdeveloped on one side of the face. "Hemifacial" refers to one side of the face, while "microsomia" refers to an abnormally small size of the body.  Although the name of the condition describes involvment of just one side of the face, both sides may be involved to varying degrees. Some children may also have an associated cleft lip and palate.

    The degree of facial difference is highly variable among individuals, ranging from mild to significant. Some children may have an underdeveloped or small jaw on the affected side, which leads to the appearance of facial asymmetry. In more severe cases, children may have a complete absence of the jaw bone. The teeth may be mildly shifted in some children; while other children have significant dental crowding, or impacted or missing teeth. The smile may appear slanted, with the affected side resting higher than the unaffected side. Differences in ear formation vary in degree as well. Some children may have slight ear irregularities, whereas others present with very limited formation of the ear. Small skin tags, may be present near the ear or cheek for individuals with this condition. Finally, in some cases, a weakness of the facial musculature may be present on the affected side, or in more severe cases a facial palsy may be assessed.

  • Goldenhar syndrome:  Goldenhar syndrome has all of the features described in hemifacial microsomia, but includes additional findings in the eyes and spine. Children with Goldenhar syndrome often have epibulbar dermoids which are benign tumors located just inside the opening of the eyes. They can also have fusion of the bones in the neck.

Cause
The exact cause of OAV is not known, however there is research to suggest that certain medications taken during pregnancy, maternal diabetes, and/or some combination of genes and environmental influences may play a role. The prevalence of both conditions is l in 3500 to l in 5000 individuals.

Diagnosis
The diagnosis of OAV is made by clinical examination by a geneticist. There is no testing to confirm the diagnosis.

Treatment/Services
Each child with OAV can benefit from an early evaluation by a craniofacial team. A craniofacial team usually includes a plastic surgeon, a head and neck surgeon, a maxillofacial surgeon, an audiologist, a speech pathologist, a nurse and a genetic counselor. The evaluation helps determine what impact the child's unique facial differences may have on hearing, speech, feeding, vision, facial, and dental development. Then, the medical team can develop a comprehensive treatment plan.

Timing of intervention can vary with the degree of severity of the condition, and the philosophies of a craniofacial team. In infancy, nursing assistance to address feeding concerns, audiological evaluation to assess hearing, and speech pathologist screening to promote communication development is appropriate. Surgery to treat a cleft lip is typically conducted around three months of age, while palatal surgery may be completed around a year of age. Treatment of the jaw abnormalities may be conducted next in order, around age three to five years. Surgical procedures to address external ear differences, follows growth of the head. Orthodontic care becomes particularly important as permanent dentition develops.

RESOURCES

Hemifacial Microsomia - General information about hemifacial microsomia from the National Craniofacial Association.

Hemifacial Microsomia - A guide to understanding hemifacial microsomia published by the Children's Craniofacial Association 

Goldenhar Syndrome - General information about Goldenhar syndrome/OAV from the National Craniofacial Association.

Goldenhar Syndrome Support Network - Information about Goldenhar syndrome and related resources.