A recent study by Mudery and colleagues found that older adults (those with an average age of 73 years) had a 71% improvement in AzBio scores in quiet and a 51% point improvement in noise on the implanted ear. When hearing was measured on both sides, the researchers found bilateral hearing improved 23% points in quiet and 27% points in noise (Otol Neurotol. 2017;38:187-191). They concluded, “All patients undergoing CI candidacy testing should be tested in both quiet and noise conditions. For those who qualify only in noise, our results demonstrate that cochlear implantation typically improves hearing both in quiet and noise.”
Bilateral versus Unilateral CIs
Part of the confusion over the guidelines is whether to place one or two cochlear implants in patients with bilateral hearing loss. Some of these decisions come down to cost.
“The medical profession is very aware of the need for bilateral hearing. We have been saying this for years with regards to hearing aids—you need two ears. But for some reason, it has taken us longer to begin that conversation with cochlear implants,” Dr. Blackburn noted. “There is an auditory perceptual advantage to hearing bilaterally. The brain is more efficient at filtering out background noise when auditory information is received from both sides.”