Congenital Hearing Loss

The goal of this clinical trial is to investigate the safety and effectiveness of cochlear implantation in infants and toddlers with single-sided deafness. The main questions it aims to answer are: * Are cochlear implants an effective treatment of single-sided deafness in infants and toddlers? * Are cochlear implants a safe treatment for single-sided deafness in infants and toddlers? Participants will receive a cochlear implant and be followed until they are five years old. During those five years, the investigators will program the device and monitor auditory development. Children will be asked to: * Undergo cochlear implantation * Wear their cochlear implant processor whenever they are awake. * Participate in traditional hearing tests * Participate in traditional hearing testing * Participate in localization testing * Participate in hearing in noise testing * Participate in word recognition testing * Participate in speech, language, and educational evaluations The researchers will compare results to children with typical hearing in both ears and children with single-sided deafness who have not received an implant to observe any differences between the groups.

This study aims to establish a novel multimodal evaluation and precision rehabilitation system for patients with congenital hearing loss who have received hearing aids, cochlear implantation, or emerging gene therapy. The proposed system will integrate age-stratified difficulty levels, combined with a gamified interaction platform or software designed to assess and train three core perceptual domains: auditory speech perception, music perception, and spatial hearing capabilities.

The study is designed to evaluate the safety, tolerability, and preliminary efficacy of EH002 for the treatment of congenital deafness caused by mutations in the OTOF gene. Participants may receive one or two injections of the EH002 gene therapy in one or both ears.

Congenital hearing loss, as well as hearing loss present at birth, is one of the most common chronic conditions in children, with a prevalence of permanent bilateral hearing loss of 2.83 per 1000 children of primary school age, which is mainly caused by genetic factors. The goal of this observational study is to learn about novel causative genes in infants with hearing loss in the Chinese population. The main problem it aims to deal with are: * to present the genetic characteristics of the infant with hearing loss in the Chinese population * to build up a prognostic model base on diverse data. Participants will be asked to receive audiological tests and collection of the peripheral blood sample.