The rare precious metal iridium has been used to produce life-changing implants that can help some profoundly deaf people hear again.

After considering using platinum for the probes, which connect straight to the patient's brain, scientists at the US's Huntington Medical Research Institutes (HMRI) decided on iridium as the perfect material for the devices.

The metal was chosen due to its strength, compatibility with the body and its resistance to the salty liquid surrounding the brain.

Patients who have lost their auditory nerves, usually as a result of tumours, are those set to benefit from the technology.

The successful production of the implants comes as a result of fifteen years of development by scientists and engineers and involved professionals from the US and Australia.

HMRI's executive director, William Opel, said: "This breakthrough is the result of two decades of HMRI research and development by dedicated scientists and technicians, supported by generous donors and the excellent National Institutes of Health grant funding."

Six patients have now benefited from the iridium implants.

Ÿ Adfero Ltd