In this recap: Complicated Cochlear Implant Cases and Evidence Based Data to Support Early Cochlear Implantation
Complicated Cochlear Implant Cases
Ted Meyer, M.D., Ph.D.
Meredith Holcomb, Au.D., CCC-A
Meyer, a surgeon, and Holcomb, and audiologist, both from the Medical University of South Carolina, shared various case studies from their patient files of complicated or unusual pediatric cochlear implant cases. Dr. Meyer began the presentation by sharing statistics about children with hearing loss, noting that approximately 40% have some kind of additional disability, and 10% have Auditory Neuropathy Spectrum Disorder (ANSD), both of which can complicate the decision of whether or not a child would benefit from a cochlear implant. The presenters shared cases of hearing loss and autism, multiple severe disabilities, ANSD, Enlarged Vestibular Aqueduct (EVA), and others to illustrate the need for a multifaceted view of CI candidates that includes perspectives from a variety of professionals on the medical team and also takes into consideration factors such as quality of life. For example, a child with multiple, severe developmental disabilities in addition to hearing loss may not achieve the stellar speech and language outcomes we would expect from a typical CI recipient, but access to sound has the potential to greatly improve that child’s connection to the world and overall quality of life.
Evidence-based Data to Support Early Implantation
Teresa Zwolan, Ph.D., CCC-SLP, LSLS Cert. AVT
Ellen Thomas, M.A., CCC-SLP, LSLS Cert. AVT
The presentation began with a discussion of the fact that, while many children are receiving cochlear implants at young ages now, there are still significant barriers to access. Dr. Zwolan noted that despite abundant evidence of the benefits of early cochlear implantation, some parents are still hesitant and some professionals still fail to refer children who could benefit. Parents may hesitate to choose CIs for their children due to misinformation, fear about surgery, cosmetic issues, or cultural/familial concerns. Professionals, as well, may delay or fail to refer appropriate candidates for cochlear implants because they are working with outdated information about CI candidate criteria, assessing candidates based only on their audiometric thresholds instead of speech perception test results, or want to maintain a relationship with the patient/family and not “lose” them to the CI team. Lack of knowledge and awareness among parents, related professionals, and members of the early intervention system leads to lost time and missed referrals for children who are in great need of access to sound. We, as members of the listening and spoken language community, need to educate these groups to make sure that cochlear implants are known as a viable option for children who could benefit.
Then, Zwolan and Thomas, from the University of Michigan’s cochlear implant program, shared data that they have collected over a number of years on hundreds of children who have received cochlear implants through their center. Across a variety of auditory, speech, language, and reading measures, the children who had received cochlear implants at under 24 months* of age outscored children in later-implanted age groups in studies that followed children 5-8 years post-implant. The studies also broke down subjects based on what type of intervention they had received: auditory-verbal, school-based auditory-oral program, or total communication. For every area tested (auditory skills, consonant production, vocabulary, language, reading, etc.), children in the AV group achieved superior scores.
What other factors contribute to success for children with cochlear implants? Zwolan and Thomas shared some important facts about literacy that are especially crucial for children with hearing loss, a group we know to be at risk for difficulties with reading. Their information included:
20 minutes of reading to your child daily translates into the child hearing 1.8 million words per year and being in the 90th percentile on reading measures. Ten minutes of reading a day means exposure to 282,000 words and 50th percentile scores. One minute of reading a day means exposure to just 8,000 words a year and 10th percentile reading performance.
Vocabulary learning needs to be contextualized, content-based, and constant. This is the opposite of lists and flashcards. For children to have rich vocabulary learning, they must have opportunities to learn words as part of natural daily routines and get repeated exposure through conversational language.
2/3 of people who cannot read proficiently by grade four end up either in jail or on welfare. Children with hearing loss are at risk, but parents can change this!
This presentation offered great evidence-based data that parents, professionals, and policymakers can use to argue for access to early cochlear implantation for all children who can benefit.
*Elizabeth’s note: The one thing that disappointed me about this presentation was that the <24m group was their youngest subject category. I asked a question and the presenters told me that their center is very conservative and does not implant children under 12 months of age. Research shows us that the current FDA guideline of 12 months is incredibly outdated, and data from other countries also supports implantation at earlier ages. (Scroll to the “Candidacy” section of this article for a list of references to support the safety and efficacy of CIs for children under 12 months of age.) Even within the <24m group, I would have liked to see a breakdown by month at age of implant. We know that there is a big difference between receiving a CI at 12 months and receiving one at almost two years of age. I predict we would see differential language outcomes had the group been broken up this way as well.