A three-year-old Cork boy can finally hear – thanks to a bionic ear installed in Manchester and pioneering treatment in America.

Identical twin Calum Geary is making incredible progress after surgery in England and intensive work at the famous John Tracy Clinic in California.

His delighted parents have told the Irish Times newspaper that the youngster has ‘shown the first signs of hearing’ after he completed the intensive specialist programme in the US.

Calum made Irish medical history earlier this year when neurosurgeons in Manchester performed the complex $100,000 operation.

Only 140 children have ever undergone the operation which sees children who were born deaf have implants inserted in their brain, which are then attached to a box in their ear.

The paper reports that although Calum’s bionic ear was activated in May, enabling him to hear sounds for the first time in his life, their son’s progress had been slow.

Andrew and Helen Geary confirmed to the Irish Times that they had noticed a huge transformation in his progress over the last three weeks after his crucial post-operative therapy.

The work – at the John Tracy Clinic in California - included basic speech production and sound-deciphering techniques.

Police sergeant Andrew Geary revealed that the intensive, six-hours-a-day course not only set Calum on the right track to a life of hearing but also equipped the family with the tools to help his development.

As part of the therapy, Calum’s twin, Donnacha, and their two older brothers, attended a specialist sibling programme at the centre of excellence.

His parents attended a separate, tailored course to teach them vital skills to aid their son’s progress.

Geary said: “The course went beyond all expectations. We have come as a whole family, from a status of a pre-lingual child with no definite signs of hearing, to a much more confident child with the very first signs of hearing.”

The Gearys will return to the US several times in the coming years to continue treatment.

Calum, born with cochlear nerve aplasia, will continue intensive therapy back home in Cork.