Cochlear Implant Complications Are Rare-But Can Be Lethal

Leaks of cerebrospinal fluid are occasionally seen at the site of device placement and through the cochlea, Dr. Gianoli continued. This generally occurs in patients with a congenital malformation of the cochlea and can be fixed by plugging up the leaks with tissue, he said.

In general, Dr. Megerian expressed confidence in the procedure and said that there is no evidence that the inner or middle ear is more vulnerable to infection in a child or adult with a cochlear implant. In the overwhelming majority of cases, there are no problems and complications, he said.

In 2006, 71 cochlear implant procedures were performed at university hospitals in Cleveland. Of these, there was one complication in a child who sustained a severe head injury near the ear with the implant, and the implant had to be replaced. Dr. Megerian said that a few of the 71 patients had implants that stopped working and had to be replaced.

Refinements in quality control have reduced the incidence of device failure dramatically, Dr. Megerian said. He said that he has not seen any failures with the Nucleus Freedom device. (Dr. Megerian has no financial interest or affiliation with the Cochlear Corporation, manufacturer of the device.) Other companies are doing a good job producing high-quality devices, he said.

Series of Pediatric Patients

A study reported at the recent Triological Society meeting described complications in a series of 247 cochlear implants in pediatric patients treated at the University of Minnesota from 1986 to 2006. Seventeen major complications were identified, for an incidence of 6.9%, which is similar to other reports in the literature, said Dr. Levine, who was a coauthor of that abstract. Sixteen of the 17 cases required explantation and reimplantation, and 11 of these were successful. This series identified a new risk factor, which is congenital syndromes involving deafness; children with these syndromes were more likely to suffer complications and to have a worse outcome than children who did not have these syndromes, Dr. Levine explained.

We were lucky because our patients tend to stay in the same geographical area and enabled 20-year follow-up. Our findings provide a good picture of complications in pediatric cases. The basic pathology has remained the same over 20 years and so has the basic surgical technique, he commented.

Acceptance by the Deaf Community

Before 1995, there were justifiable concerns about the wisdom of performing cochlear implant surgery in a child who was born deaf, because of the possibility that the implant would interfere with the development of normal language skills. An article published in 1996 laid that fear to rest with a study showing that 90% to 95% of children with an implant will develop an open set of language skills, Dr. Megerian said.