Cochlear Implantation Outcomes in Children With <i>CDH23</i> Mutations-Associated Hearing Loss.

Abstract

Mutations in the cadherin 23 gene (<i>CDH23</i>) have been reported to cause cochlear damage, but few studies have investigated the auditory and speech outcome of patients after cochlear implantation. Here, we describe the genetic, auditory, and postoperative outcomes of patients with <i>CDH23</i> mutations who received cochlear implants. Retrospective case review. Tertiary referral center. Targeted deafness-related gene panels were sequenced in Chinese families with profound sensorineural hearing loss. The clinical features of subjects carrying potentially pathogenic <i>CDH23</i> mutations were analyzed. Between 2017 and 2019, we identified 5 children with prelinguistically profound hearing loss at our center who harbored 6 variants of <i>CDH23</i> that segregated with the disease. Of these, 4 variants were novel (c.2591G>T, c.4785G>C, c.5765A>G, and c.9280_9281insTT). All affected individuals had a loss of outer hair cell function, with an average residual hearing level of 3 to 10 dB SPL. Cochlear implantations were arranged for the patients at 11 to 36 months of age. All children made gains in their hearing, language, and speech performances 14 to 120 months after surgery. Their auditory outcomes improved during follow-up intervals. This study revealed that children with congenital cochlear defects caused by <i>CDH23</i> variants can acquire an acceptable auditory and speech outcome after cochlear implantation. Early genetic detection and prenatal counseling for rare deafness genes such as <i>CDH23</i> remain a priority for the future.