Causes of Facial Paralysis
Hemifacial Microsomia
Hemifacial Microsomia is a condition in which the lower half of one side of the face is underdeveloped and does not grow normally. It is sometimes also referred to as first and second brachial arch syndrome, oral-mandibular-auricular syndrome, lateral facial dysplasia, or otomandibular dysostosis. The syndrome varies in severity, but always includes the maldevelopment of the ear and the mandible. This is the second most common facial birth defect after clefts.Researchers are still not sure why this happens, however, most agree that something occurred in the early stages of development such as a disturbance of the blood supply to the first and second branchial arches in the first 6 to 8 weeks of pregnancy. Studies do NOT link this condition with the mother's activities or actions during her pregnancy.
For parents with one child with hemifacial microsomia, the chances are between 0 and 1%. Adults with this condition have a 3% chance of passing it to their children.
The surgeries recommended for children with hemifacial microsomia have a goal to improve facial symmetry, by reconstructing the bony and soft tissue, and establishing normal occlusion and joint junction. The timing for such surgeries varies among the surgeons and the severity of the problems. Common surgeries include:
- Lowering the upper jaw to match the opposite side and lengthening the lower jaw. Sometimes a bone graft is used to lengthen the jaw and sometimes a distraction device is used.
- Ear reconstruction at about 5-6 years of age, involves 3 to 4 surgeries.
- Occasionally, it may be necessary to add bone to build up the cheekbone.
- Some children benefit from the addition of soft tissues to further balance the face.
Your child may have skin tags in front of the ear or on different parts of the face. Hearing problems depend on the structures that are involved. Some children have some weakness in movement on the affected side of the face.
