Factors that influence performance in pediatric cochlear implant recipients with cochlear nerve deficiency

Children with cochlear nerve deficiency (CND) have wide variability in outcomes with cochlear implant (CI) use. The current study aims to report a large cohort of pediatric CI recipients with CND and to evaluate for factors that may predict improved performance.

The current study is a retrospective review of pediatric CI recipients with CND at a tertiary academic hospital. Variables including cochlear nerve status (hypoplasia vs aplasia), age at implantation, cochleovestibular malformation, bony cochlear nerve aperture, internal auditory canal aperture, and cognitive delay were evaluated for predictors of postoperative performance. A stepwise multinomial regression analysis was performed.

Forty-seven CI recipients (54 ears) were included in the analysis. A majority (59%) showed auditory capabilities with their CI. Twenty percent of recipients achieved some level of open-set speech perception with their CI. The regression analysis identified cochlear nerve status and cognitive delay as predictors of performance. CI recipients with cochlear nerve hypoplasia had significantly improved performance compared to those with aplasia (p = 0.003). Recipients with cognitive delay had more limited benefit than those without cognitive delay (p = 0.033).

Children with CND can benefit from CI use, with outcomes spanning from non-use to development of spoken language. Predictive factors for improved performance include a lack of cognitive delay and cochlear hypoplasia rather than aplasia. These can be important considerations for parent counseling and decision making.