Microtia generally refers to congenital dysplasia of the auricle, often accompanied by atresia of the external auditory canal, and in some patients, also accompanied by malformations of the maxillofacial development and malformations of the external and middle ear development, but the inner ear is basically normal, so hearing is more affected by the air-conducted part and the bone-conducted hearing part is normal. There are also some small ear deformities that are caused by trauma or burn injuries. Currently, for ear reconstruction surgery, we believe that the minimum age for surgery should be after the age of 6. In order not to affect the normal psychological development and learning of the child, it is best to have the surgery before school age so that the child can have normal ears and go to school as happily as other children, so that he or she will not be discriminated against by children of the same age and cause permanent psychological problems. Diagnosis of binaural hypoplasia: Diagnosis can be made based on medical history, clinical symptoms and laboratory test data. There are as many as ten types of middle ear developmental disorders in patients with congenital microtia, mainly developmental malformations of the auditory tuberosity, tympanic muscles and facial nerve, and they are closely related to the severity of the external ear malformation. In severe cases, congenital malformations of the external ear can manifest as one of the clinical signs of the sequence, such as the oculo auriculo vertebral spectrum (OAVS). In addition to microtia, patients also have hemifacial shortening (temporal, maxillary or mandibular hypoplasia), soft tissue deformities (preauricular redundancy or macroglossia), eyelid defects (eyelid defect, conjunctival epithelial cyst), spinal deformities, and congenital renal and cardiac defects. The size and shape of the auricle changes, but important surface marker structures of the auricle are present, the external auditory canal is narrowed, and in severe cases the external auditory canal appears atretic. 1. In mild cases, the shape of the auricle approximates normal, but is significantly smaller. 2. In severe cases, the ear is defective, leaving only an irregular flab, containing cartilage, and the earlobe is poorly developed and displaced. 3.It may be accompanied by atresia of the external auditory canal or ipsilateral facial dysplasia.