About 30,000 new deaf children are born each year in China, of which congenital sensorineural hearing loss (SNHL) accounts for a significant proportion. About 20-30% of patients with SNHL can be found to have abnormal development of the bony vagus structures in the inner ear by imaging (mainly CT). Inner ear malformations can be classified as non-syndromic or syndromic depending on whether they are associated with abnormalities of other structures or organs. Previously, non-syndromic malformations were classified into the following four types (Jackler 1987 classification): 1. Mondini type: cochlear hypoplasia, usually only one and a half weeks or two weeks, with hypoplasia of the Corti apparatus and spiral ganglia, and varying degrees of vestibular disturbances; 2. Scheibe type: cochlear balloon type, with milder lesions, bony cochlea and elliptical This type has a milder lesion with normal development of the bony cochlea and elliptical semicircular canal, the malformation is limited to the cochlear canal and balloon, and the inner ear is partially functional. The most serious form of inner ear malformation is the Michel type, in which the inner ear may be completely undeveloped (cochlea is absent), and in severe cases the temporal bone is also underdeveloped, which may be accompanied by malformations of other organs and mental retardation. In addition to malformations of the outer ear, middle ear and inner ear, syndromic ear deformities can be associated with malformations of other organs, limbs or internal organs. There are many different syndromes, such as Usher syndrome with retinitis pigmentosa, Pendred syndrome with goiter, Weardenburgs syndrome with exocytosis of the inner canthus and tear dots, and Ven der Hoeve syndrome with blue sclera. With the recent advances in cellular molecular biology, genetics and embryonic development, the classification criteria for inner ear developmental malformations are constantly updated and refined, and the differences between Chinese and foreign data are increasingly appreciated and recognized. For example, in the large vestibular conduction canal, foreign patients mostly present with Pendred’s syndrome of deafness with goiter, whereas it is not uncommon for domestic patients to present with goiter. Therefore, the classification of developmental malformations of the inner ear will be a continuous process of deepening and updating. In the following, I will give you a brief introduction of the new classification criteria that are gradually recognized and accepted by domestic and foreign scholars. According to the location and severity of the malformation, inner ear malformations are divided into the following types (Sennaroglu 2002 classification criteria): 1. (3) Incomplete separation type I malformation: a cystic cochlear vestibular malformation without a cochlear axis and sieve area (the area between the cochlea and the internal auditory canal), resulting in a cystic appearance with a large cystic vestibule; (4) Cochlear hypoplasia: a cochlea and vestibule that are differentiated but not of normal size (cochlea less than 4 mm in height or cochlea less than 2. 5 gyrs); (5) Incomplete separation type II malformation: Mondini malformation, (5) Incomplete separation type II malformation: Mondini malformation, in which the cochlea contains 1.5 gyrus, part of the cochlear axis, the middle gyrus and the parietal gyrus are fused to form a capsule with an enlarged vestibule and enlarged vestibular aqueduct. 2. Vestibular malformations: including Michel’s malformation, common cavity malformation, vestibular hypoplasia, vestibular hypoplasia, and vestibular enlargement. 3. Semicircular canal malformation: including absent semicircular canal, hypoplastic semicircular canal, enlarged semicircular canal. 4.Internal auditory canal (IAC) malformation: including IAC absence, IAC stenosis, IAC enlargement (IAC diameter ≥ 8 mm is IAC enlargement, IAC ≤ 2 mm is IAC stenosis). 5. Vestibular and cochlear aqueduct malformations: enlarged vestibular or cochlear aqueducts (no cochlear aqueduct malformations have been reported so far). The theoretical basis for the adoption of the new classification is based on embryologic development. These malformations can occur in different areas and to different degrees during different periods of embryonic development when the development of the inner ear is affected and developmental arrest occurs. The significance and value of the new classification criteria is also to help physicians determine the nature and extent of inner ear malformations as accurately as possible, in order to help patients’ families choose the best treatment and implantation device. Prior to 1983, inner ear malformations were contraindicated for artificial hearing implants. With the development of technology, many patients with inner ear malformations have been able to obtain functional hearing through cochlear implants in recent years. However, cochlear implants cannot be used for cochlear dysplasia and auditory nerve deficiency, and in the future, auditory brainstem implants or even auditory midbrain implants may be able to help these patients return to the world of sound. The occurrence of inner ear malformations is partly related to genetic factors and partly related to environmental factors. In addition to genetic factors, environmental factors should be taken into account. In addition to paternal factors, the mother-to-be should especially avoid the effects of physical and biochemical factors such as radiation, drugs, alcohol, viral or bacterial infections during pregnancy.