Children with hemifacial microsomia have a lower half of one side of the face that is underdeveloped and does not grow normally.
Hemifacial microsomia is a congenital (present at birth) condition in which the lower half of one side of the face is underdeveloped and does not grow normally. The second most common facial birth defect after cleft lip or palate, hemifacial microsomia always affects the development of the ear and mandible (jaw).
Researchers believe that hemifacial microsomia is caused by a disturbance of the blood supply to the fetus during the first trimester of pregnancy. The reason for the disturbance is unknown.
Symptoms at birth
Signs and symptoms of this condition range in severity. Symptoms that appear when the baby is born include:
Abnormally shaped or missing ear
Facial features that appear smaller on one half of the face
Flattened forehead or cheekbone
Slightly smaller jaw on one side of the face
Skin tag in front of the ear
Small and underdeveloped eyes
Unequal cheek fullness
As a child with hemifacial microsomia grows and develops, he or she may exhibit some or all of the following: