• The participant and/or their legal guardian must provide informed consent before the study, voluntarily sign the written informed consent form, and be willing to attend follow-up visits as scheduled by the study.

• The participant must communicate effectively with the investigator and comply with the investigator's requirements, with the assistance of a legal guardian if necessary. Young children without mature language skills must be able to cooperate and comply with the investigator's requirements with the help of a legal guardian.

• The participant and/or legal guardian must understand the study correctly and have appropriate expectations regarding the potential benefits.

• The participant must be at least 6 months old, with no restrictions on gender.

• The participant must be diagnosed with DFNB9 congenital deafness, confirmed by genetic testing showing homozygous or compound heterozygous mutations in the OTOF gene.

• Audiological inclusion criteria: Severe or profound hearing loss (≥65 dB).

• The participant must meet the surgical requirements, including the absence of middle- or inner-ear malformations, vestibulocochlear nerve developmental abnormalities, and ear inflammation, as confirmed by CT or MRI scans within 3 months or at the time of screening. Additionally, the participant must be deemed eligible for surgery.