The incidence of microtia is characterized by more males than females, single case more than bilateral, and right side more than left side. Most patients with congenital microtia can't find genetic factors at work, and some mothers have a history of virus infection, radiation and medication in the early pregnancy, but in general, there is no clear cause of congenital microtia, let alone clear genetic factors. Modern medicine has not found enough evidence to prove the real cause of this disease.

Congenital microtia and atresia of external auditory canal often occur together, which is caused by hypoplasia of the first and second branchial arches or the first branchial groove during embryonic development, and may be accompanied by eustachian tube, tympanum or mastoid malformation caused by hypoplasia of the first pharyngeal sac.

Classification: Type I: The auricle is smaller than normal, and the external auditory canal and tympanic membrane exist, which is acceptable for hearing. Type ⅱ: auricle deformity, atresia of external ear, undeveloped tympanic membrane and malleus stalk, fusion of incus and malleus, with or without stapes. Hearing deafness, which is relatively common. The third type: auricle deformity is serious, external ear atresia, ossicular deformity, combined with non-branchial cleft inner ear deformity. Loss of inner ear function. The second and third types are sometimes accompanied by maxillofacial dysplasia, which is called Terje-Koehler syndrome. Temporal bone CT: external ear atresia, tympanic stenosis, ossicular deformation.

Treatment: For the first one, auricle repair can be performed; For the second type, external auditory canal plasty and tympanoplasty can be performed, and practical hearing can be obtained after operation; For the third type, due to serious deformity and loss of inner ear function, the ear reconstruction center in Lido, Beijing has realized one-off ear canal reconstruction and tympanoplasty. Patients with binaural malformation and good cochlear function should be operated as soon as possible. Generally, surgery can be performed when the child's own cartilage has enough auricles, so as not to affect language learning. Generally speaking, if one side is deformed and the other side is normal, surgery should be performed at the age of 8 ~ 9 or later. Promote the cooperation of patients