Double Benefit? The case for bilateral cochlear implants

Dr. Woolley recommends either simultaneous implants or bilateral implants with a limited interstage interval for a majority of his patients. “The cost is going to be much less if you do simultaneous because you’re going to have one OR [operating room] time. You’re not going to have two anesthesia charges. You’re not going to have two hospitalizations,” he explained.

At Children’s Hospital of Philadelphia, the standard procedure is to implant bilateral cochlea sequentially. “The main reason for that approach is that we like to verify that the children are responding well to the first implant, and that they’re getting good benefit initially, before proceeding with the second,” explains John Germiller, MD, assistant professor of otorhinolaryngology at the University of Pennsylvania/Children’s Hospital of Philadelphia, where he is also director of clinical research for otolaryngology.

As well, Dr. Germiller said that there may simply be no significant medical advantage to doing two at once: “So far there are not overwhelming data that prove that if you do it simultaneously it’s better than if you do it with a short delay…meaning under a year between the two, and ideally, under six months.”

There may be some absolute indications for bilateral implantation, according to Craig Buchman, MD, professor and chief of neurotology and skull-based surgery and medical director of the Carolina Children’s Communicative Disorders Program (CCCDP) at the University of North Carolina, Chapel Hill. “If a child is deafened from meningitis and they have ongoing cochlear ossification, they probably should get bilateral implants acutely or with a very limited inter-device interval,” he said. “If a child has progressive or complete visual loss, bilateral implants are really strongly indicated for the sound localization issues. If a child is blind, I believe that bilateral implants should be best practice.”

Some clinicians may be concerned by the possibility of increased complication rates with bilateral implants. “There’s no difference in complications with one versus two,” Dr. Woolley said. “There’s no difference with hospital length of stay. There’s no difference in the amount of pain or discomfort or the amount of nausea. So, for us, the only difference is a little bit of increase in length of surgery, obviously, because you’re doing two ears instead of one.”

The Case for Unilateral Implantation

A number of factors can influence the decision to implant a single cochlea versus two. One instance in which unilateral implantation would be seriously considered is the child who is profoundly hearing impaired in one ear but has residual hearing in the second ear. “If a child has a lot of residual hearing, we may err on the side of doing an implant on one side and then use a hearing aid in the contralateral ear for a period of time to see how they do,” Dr. Buchman said. “As you start adding in more residual hearing, the decision making becomes dramatically more complicated because the issue becomes whether the child can gain benefit from a second-side hearing aid versus a cochlear implant,” he explained. “I don’t think that we know all the answers to how much hearing is considered good enough to save.”