Two cochlear implants are better than one.

Boons T, Brokx JPL, Frijns JHM, Peeraer L, Philips B, Vermeulen A, et al. Effect of pediatric bilateral cochlear implantation on language development. Arch Pediatr Adolesc Med 2012;166:28-34. Among prelingually deaf children, does bilateral cochlear implantation, compared with unilateral implantation, result in improved spoken language outcomes? Case-control, retrospective, cross-sectional, multicenter study. Two Belgian and 3 Dutch cochlear implantation centers. 25 children with 1 cochlear implant matched (on 10 auditory, child, and environmental factors) with 25 children with 2 cochlear implants. Both groups of children were selected from a retrospective sample of 288 children who underwent cochlear implantation before 5 years of age. Performance on measures of spoken language comprehension and expression (Reynell Developmental Language Scales and Schlichting Expressive Language Test). In those children who had bilateral implants, the authors also evaluated the impact on language development based on the interval between the first and second implants. On the receptive language tests, children undergoing bilateral implantation performed significantly better than those undergoing unilateral implantation (mean difference [95% CI], 9.4 [0.3-18.6]) and expressive language tests (15.7 [5.9-25.4] and 9.7 [1.5-17.9]). Because the two groups were closely matched, the authors argue that the difference in performance mainly can be attributed to bilateral implantation. In addition, for those children with bilateral implants, a shorter interval between the implants was related to higher standard scores. Children undergoing 2 simultaneous cochlear implantations performed better on the expressive Word Development Test than did children undergoing 2 sequential cochlear implantations. The use of bilateral cochlear implants is associated with better spoken language learning. The interval between the first and second implantation correlates negatively with language scores. On expressive language development, there is an advantage to simultaneous versus sequential implantation.