The world's top maker of bionic ear implants said today that the risk of meningitis in its implant patients was no higher than in the general population.

Sydney based Cochlear Ltd made the statement after its shares plunged on the stock market after a warning from the US Food and Drug Administration that inner-ear implants may put patients at greater risk of contracting meningitis.

Cochlear is a manufacturer of cochlear implants for the hearing impaired, through its Nucleus product range.

The Nucleus system is sold in more than 60 countries with research and development facilities in Australia and Belgium and offices in the United States, United Kingdom, Switzerland, Germany, Japan, Bangkok, China and Hong Kong.

"The overall incidence of meningitis in its worldwide Nucleus recipient community is similar to the incidence of meningitis in the general population," the company said.

Cochlear said it had contacted leading medical experts to conduct an independent review of all reported cases of meningitis in Cochlear's nearly 40,000 Nucleus implant recipients.

©AAP 2002