Deaf boy now reacts to sound after experimental surgery

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A deaf three-year-old Montreal boy who underwent experimental surgery in the United States to replace his missing auditory nerves with an electronic implant now bolts upright and turns his head at the sound of a barking dog.

Little Auguste and his parents, Christophe Majkowski and Sophie Gareau, face a long road of therapy and training to turn this gift of rudimentary hearing into a useful sense that might one day allow him to hear words and speak – perhaps even carry on a telephone conversation – and pave the way for other deaf children in North America.

"It's really hard to tell at this stage what he can hear, but we do see reactions to sound, especially in his therapy sessions," Ms. Gareau said in an interview 10 weeks after Auguste's May 6 surgery. "The dog barking was something else. He looked up, turned around, and pointed to his ear. It was a special moment."

Doctors in the United States have started clinical trials to test the auditory brain-stem implant (ABI) on children. The implant is used to replace damaged or missing auditory nerves that transmit sound from the ear into the brain to give profoundly deaf people some auditory sense. Auguste was among the first of a handful of children scheduled to receive the ABI this year.

The procedure and device go a big step further than the cochlear implant, the now-common device used to stimulate the auditory nerve that has allowed about 300,000 people worldwide to hear. The ABI transmits audio signals from a sensor behind the ear directly into the brain stem. Surgeons install the implant deep into the brain in a procedure with much greater risk than the cochlear installation.

Dr. Mark Krieger, a pediatric neurosurgeon at Children's Hospital Los Angeles, was part of the team that performed Auguste's surgery. He's part of a neurosurgery department that does up to 600 brain surgeries a year. He said he jumped at the chance to help open a new field of "functional surgery" aimed at adding to a child's cognitive abilities.

Dr. Krieger said the number of children missing an auditory nerve is very small, and even fewer do not suffer from a host of other medical and cognitive problems that would make the surgery impractical. He said Auguste is a rare, ideal candidate who has high intelligence, is doing well cognitively, and has a loving and supportive family ready to put in the time and resources needed to take the next step.

"Sophie is an amazing woman. She has kept her expectations realistic. At one point, she told me that if her son ends up being able to hear the fire alarm in a burning building, it will be worth it," he said. "My goals are substantially higher in terms of benefit."

The California trial has funding from the National Institutes of Health and approval from the Food and Drug Administration to implant the device in 10 children over three years.

The procedure has existed for decades, but was long considered too risky to use on otherwise healthy people, especially children. The ABI implant was first used on an adult patient in 1979 to replace auditory nerves destroyed by tumours. Over the next 30 years, progress was slow.

One of the pioneers of the ABI technology, biomedical engineer Robert Shannon, said that by the late 1990s, 25 to 35 patients a year who were made suddenly deaf by the removal of a tumour and nerve had some hearing restored by the implant.

"It was moderately successful, but not great. We were used to cochlear results, where patients can carry on a conversation on the telephone, and this wasn't that," he said. "People were very nervous about it. It's a fairly risky operation. Getting to the brain stem is not a trivial procedure. So to take those risks with modest gains, people didn't think it was that good a tradeoff."

In the late 1990s, an Italian doctor named Vittorio Colletti began putting the device in otherwise healthy deaf people. He was dismissed as a "cowboy" in North American medical circles. In 2004, he invited Robert Shannon, professor of otolaryngology at the University of Southern California, to review his results. "I was completely astounded," Dr. Shannon said. "The results weren't as good as he said – they were better. I had a certain amount of credibility in the field because I was one of the developers of the early brain-stem implant. People who were writing him off listened to me."

Dr. Shannon found about one-third of Dr. Colletti's patients could carry on telephone conversations. "In my mind, the phone is the gold standard," Dr. Shannon said. "No visual cues."

Dr. Colletti had refined the procedure, reducing risk, Dr. Shannon said. Moreover, he got substantially better results by operating on otherwise healthy deaf patients lacking auditory nerves by a genetic quirk, boosting the reward side of the equation. "He took the leap that really changed the field," Dr. Shannon said.

That risk calculation weighs heavily on Auguste's surgeon, Dr. Krieger. "If you ask my wife, she will tell you my whole life is about calculating risk and reward. When to operate, when to try other treatments," Dr. Krieger said. "The whole purpose of this study is to quantify risk."

Auguste's mother, Ms. Gareau, said she was initially against the surgery, but was convinced by the FDA approval, the NIH funding for the operation, and the selection of her son to be the first California patient.

There were tough days. Auguste had to undergo a second procedure to release fluid building up on his brain a few days after surgery. Recovery included weeks of pain and vomiting. But he's back to normal now, learning sign language and taking therapy. Ms. Gareau says sign will always be one of at least three languages spoken in the family, alongside French and English.

And then there's cost. While the NIH covered the surgery and device, repeated and lengthy trips to California have cost tens of thousands of dollars. The community has pitched in to contribute funds.

"When we first met these guys in 2012, I was sort of against the surgery. I didn't feel there was a need," Ms. Gareau said. "But there was no pressure, and I just followed the path all the way through. I think I would say it was worth it right now. He's still healthy – there's enormous potential. Now if the outcome had been different in terms of health … it's always scary. But so far, so good."

Editor's note: An earlier version of this story suggested Dr. Mark Krieger performs 600 surgeries to remove tumours each year. The figure is for all brain surgeries by his department.