Cochlear implant is a biomedical engineering device that can help people with hearing impairment to restore their hearing and speech communication ability. Cochlear implant is a new technology in the field of medicine and rehabilitation and is constantly updated with the development of science and technology, therefore, there is a need for a guideline for reference in the selection of the indications, preoperative evaluation, surgery, postoperative adjustment and auditory-verbal rehabilitation. On the basis of the 2003 edition, we have made reference to a large number of domestic and international related literature. We have revised the guideline comprehensively, aiming to provide guidance for clinicians, hearing and speech rehabilitation and other related fields, to further standardize cochlear implantation in China, and to improve the overall therapeutic and rehabilitative effects. Cochlear implantation involves many fields such as medicine, audiology, biomedical engineering, pedagogy, psychology and sociology, and requires physicians, audiologists, speech pathologists, speech therapists, rehabilitation teachers, engineers and parents to form a cochlear implantation team and work together. I. Patient selection criteria: Cochlear implantation is mainly used to treat severe or profound sensorineural deafness in both ears. 1. Selection criteria for prelingually deaf patients: ① The age of implantation is usually 12 months to 6 years old. The younger the age of implantation, the better the results, but special precautions should be taken to prevent complications such as anesthesia accidents, excessive blood loss, and damage to the facial nerve inside and outside the temporal bone. It is not recommended to implant cochlear implants in children younger than 6 months of age, but in cases of deafness caused by meningitis, it is recommended to operate as early as possible when the surgical conditions are complete because of the risk of cochlear ossification. children or adolescents older than 6 years of age need to have a certain degree of basic hearing and speech, and have a history of wearing hearing aids and a history of auditory-verbal rehabilitation training since childhood. ② Severe or profound sensorineural deafness in both ears. After comprehensive audiological evaluation, children with severe deafness wearing hearing aids for 3 to 6 months is ineffective or the effect is not satisfactory, cochlear implantation should be carried out; children with extreme deafness can be considered to directly carry out cochlear implantation. There is no contraindication to surgery. The guardian and/or the implantee should have correct understanding and appropriate expectation of cochlear implantation. ⑤ Possess the conditions of auditory-verbal rehabilitation education. 2. Selection criteria for post-speech deaf patients: ① Post-speech deaf patients of all ages. ② Severe or extremely severe sensorineural deafness in both ears, unable to carry out normal auditory-verbal communication by relying on hearing aids. ③No contraindications for surgery. ④ The implantee himself/herself and/or the guardian has the correct understanding and appropriate expectation of cochlear implantation. Absolute contraindications: severe malformation of the inner ear, such as Michel’s malformation; absence or interruption of the auditory nerve; acute suppurative inflammation of the middle ear mastoid. Relative contraindications: frequent epileptic seizures that cannot be controlled; serious mental, intellectual, behavioral and psychological disorders, unable to cooperate with auditory-verbal training. Guiding recommendations for clinical practice of cochlear implantation in special cases 1. Cerebral white matter lesions: also known as cerebral white matter dystrophy, is a group of lesions mainly involving the white matter of the central nervous system, which is characterized by abnormal development of myelin sheaths or diffuse damage to the white matter of the central nervous system. If MRI reveals a cerebral white matter lesion, intellectual and neurologic signs and MRI review are required. If there is no regression in intellectual and motor development, the function of other systems except hearing and speech is basically normal, there is no positive pyramidal sign or no change in neurological signs, and there is no high signal in the white matter lesion area of MRI (DWI image); and there is no enlargement of the lesion in the dynamic observation (the interval is more than 6 months), cochlear implantation can be considered. 2. Auditory neuropathy (auditory neuropathy spectrum disorder): it is a special kind of neurological deafness, which is caused by the malfunction of inner hair cells, auditory nerve synapses and/or the auditory nerve itself. Audiological testing is typically characterized by normal otoacoustic emissions (OAE) and/or cochlear microphonic potentials (CM) and absent or severely abnormal auditory brainstem responses (ABR). Currently, cochlear implantation is effective in improving hearing in most patients with auditory neuropathy, but it may be ineffective or ineffective in some patients, so the patient and/or guardian must be informed of the risks before surgery. Bilateral cochlear implantation: Bilateral implantation can improve sound source localization, speech comprehension in quiet and background noise, help to obtain a more natural sound perception, and promote the development of auditory speech and music appreciation. Bilateral implantation or sequential implantation can be chosen. The shorter the interval between two surgeries for sequential implantation, the more favorable it is for postoperative speech rehabilitation. 4. Cochlear implantation for people with residual hearing: People with residual hearing, especially those with high-frequency steeply falling hearing loss are suitable for electrode implantation with residual hearing preservation, and can choose acoustic-electrical co-stimulation mode after the operation, but the patient and/or guardian must be informed of the risk of residual hearing decline or loss after the operation. 5. Cochlear implantation in patients with structural abnormalities of the inner ear: structural abnormalities of the inner ear related to cochlear implantation include common cavity malformation, cochlear dysplasia, cochlear ossification, and stenosis of the internal auditory canal, etc. Most of the patients can be implanted with cochlear implants, but a case discussion should be organized before the operation, and the patient should be handled with caution during the operation, and the use of facial nerve monitoring is recommended. The postoperative effect varies greatly among individuals. 6, chronic middle ear with tympanic membrane perforation cochlear implantation: chronic otitis media with tympanic membrane perforation if the inflammatory reaction has been controlled, can choose a phase or staged surgery. One-stage surgery means that cochlear implantation is performed at the same time of radical treatment of middle ear mastoid lesions, tympanic membrane repair (or mastoid cavity autologous tissue filling and external auditory canal closure); staged surgery means that the lesions are removed, the tympanic membrane perforation is repaired, or the external auditory canal is closed, and then cochlear implantation is performed 3 to 6 months later.