What aspects of the cochlear implant evaluation are performed prior to surgery? Before surgery, the surgeon must carefully complete a preoperative evaluation, as this is the key to the successful completion of the surgery. The preoperative evaluation includes the following aspects: ① Systematic collection and compilation of medical history, including family history and genetic examination according to the patient’s condition; ② Comprehensive audiological examination results to assess the patient’s hearing and speech ability; ③ Detailed and meticulous evaluation based on CT, MRI and other imaging examinations, including: understanding the anatomical variation of the middle ear; clarifying the alignment, structure and development of the inner ear and auditory nerve; determining the tympanic nerve and facial nerve alignment and spacing, and formulating different surgical pathways; and ④ Measure the length of the cochlear canal and select the appropriate length electrode for implantation; ⑤ Predict possible intraoperative complications and safety factors that may affect the surgery according to the patient’s condition; ⑥ Evaluate the patient’s postoperative learning and speech in the context of behavioral, intellectual and psychological development. Assess the patient’s postoperative learning and speech rehabilitation ability, etc.