London: Functionally deaf patients can now gain normal hearing with a new implant that replaces the middle ear, scientists claim.
The unique invention from the Chalmers University of Technology in Gothenburg, Sweden has been approved for a clinical study as the first operation was performed on a patient last month.
With the new hearing implant, developed in collaboration with Sahlgrenska University Hospital in Gothenburg, the patient undergoes an operation to insert an implant slightly less than six centimetres long just behind the ear, under the skin and attached to the skull bone itself.
The new technique uses the skull bone to transmit sound vibrations to the inner ear, so-called bone conduction.
"You hear 50 per cent of your own voice through bone conduction, so you perceive this sound as quite natural," said Professor Bo Hakansson in a statement.
Unlike the type of bone-conduction device used today, the new Bone Conduction Implant (BCI) does not need to be anchored in the skull bone using a titanium screw through the skin. The patient has no need to fear losing the screw and there is no risk of skin infections arising around the fixing.
The first operation was performed on December 5, 2012 by Mans Eeg-Olofsson, senior Physician at Sahlgrenska University Hospital, Gothenburg, and went entirely according to plan.
"Once the implant was in place, we tested its function and everything seems to be working as intended so far. Now, the wound needs to heal for six weeks before we can turn the hearing sound processor on," said Mans Eeg-Olofsson, in charge of the medical aspects of the project.
The technique has been designed to treat mechanical hearing loss in individuals who have been affected by chronic inflammation of the outer or middle ear, or bone disease, or who have congenital malformations of the outer ear, auditory canal or middle ear. Such people often have major problems with their hearing.
Normal hearing aids, which compensate for neurological problems in the inner ear, rarely work for them. On the other hand, bone-anchored devices often provide a dramatic improvement.