Type of disease: Rare conditions
Hemifacial microsomia (HFM) is a condition in which part of one side of the face is underdeveloped and does not grow normally. The eye, cheekbone, lower jaw, facial nerves, muscles, and neck may be affected. Other findings may include hearing loss from underdevelopment of the middle ear; a small tongue; and macrostomia (large mouth). HFM is the second most common facial birth defect after clefts. The cause of HFM in most cases is unknown. It usually occurs in people with no family history of HFM, but it is inherited in some cases. Treatment depends on age and the specific features and symptoms in each person.
Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.