"A changing indication of people going from unilateral to bilateral is an important driver of the business," Roberts said in an interview in Sydney. "The technology is spectacular."

Roberts has started selling improved hearing devices after taking advantage of recalls by competitors to win market share and increase sales in the U.S., Cochlear's biggest market, and Europe, its fastest growing. In March he won regulatory approval to sell a model the company says is four times more reliable than competing implants, is water resistant and has a longer battery life.

"It has by far the best hearing performance available, very high reliability and lots of accessories we can add," he said.

Roberts said there is more opportunity for growth from research and development rather than acquisitions. The company spent A$50 million ($37 million) developing its latest model, Nucleus Freedom, which has helped increase global market share to about 70 percent.

"We do believe there are a lot of opportunities for developing implantable devices for the hearing impaired," he said. "There are not a lot of acquisitions to do."

Roberts reaffirmed his forecast for earnings growth of at least 20 percent.

Cochlear shares rose A$1, or 2.7 percent, to A$37.50 at 10:25 a.m. in Sydney. The stock has climbed 49 percent this year, making it the fifth-best performer in the 38-member Morgan Stanley Capital International Asia Pacific Health Care Index.

Cochlear's implants treat people with profound hearing loss who can only hear sounds of 90 decibels or more, such as a loud truck or chainsaw.

By Vesna Poljak
http://www.bloomberg.com/apps/news?pid=10000081&sid=anV9hLXbhEpc