FDA OKs First Hearing Device Capable of Bypassing Nerves in the Ear
Oct. 24, 2000 (Washington) -- U.S. health officials have approved the first device capable of bypassing the hearing nerve to transmit sounds directly to the brain.
FDA officials said Monday that they approved the Nucleus 24 Multichannel Auditory Brainstem Implant (Multichannel ABI), a device capable of stimulating the area of the brain that normally receives electrical signals from the ear. To use the device, the patient wears a pocket-size speech processor that picks up sound and changes it into electrical pulses that are then transmitted to the implant.
The device was approved for teenagers and adults who suffer from neurofibromatosis type 2 (NF2), a genetic condition that affects about one in every 40,000 Americans. The condition is characterized by the development of tumors on various nerves and is diagnosed by the hearing loss patients usually suffer in their late teens or early 20s.
When the tumors are removed, it is often necessary to also remove parts of the hearing nerve, causing total deafness. As a result, hearing aids and inner ear implants do not help. Although the gene that causes NF2 has been identified, there currently is also no available treatment other than surgery.
But the Multichannel ABI is not for all people, according to the FDA.
The approval was based on a clinical study, in which 82% of the 60 evaluated participants were able to hear familiar sounds such as honking horns and doorbells, the FDA said in a prepared statement. About 85% were capable of understanding conversation with the aid of lip reading, and 12% were able to hear well enough to use the phone. But another 18% were not able to hear anything, either because the implant migrated following the surgery or because the implant was misplaced during the surgery, the FDA said.
Although the Multichannel ABI was only tested on 60 people, the device was given an expedited review because of the severity of NF2 and the recommendation of an expert FDA advisory panel, which voted to support the device's approval in July, the FDA said.