Cochlear implants have transformed the lives of hundreds of thousands of people around the world by restoring lost hearing. But externally worn sound processors outside the ear have long been a source of friction, limiting daily activities and exposing users to stigma. A new, fully implanted cochlear implant from Austrian company Med-El now offers the prospect of round-the-clock hearing without any visible sign.
Since the 1980s, cochlear implants have been used to bypass damaged parts of the ear in people with severe-to-profound hearing loss. Conventional devices feature an external unit worn on the back of the ear that houses a microphone, sound processor, and battery. This unit converts incoming sounds into electrical signals that are transmitted wirelessly through the scalp to an electrode array in the cochlea—a spiral shaped structure in the inner ear that converts sound waves into neural signals.
Med-El CEO Ingeborg Hochmair, who developed one of the first multichannel cochlear implants in the 1970s in collaboration with her husband Erwin, says the ambition to create a fully implantable device dates back to the 1970s, but was held back by microphone and battery technology. But after more than 15 years of development, on Tuesday the company launched the TICI Unico, the world’s first commercially available fully implanted cochlear implant (or TICI, Totally Implantable Cochlear Implant).
The device has received European regulatory approval and the first four commercial implantations were carried out on the morning of the announcement, though it’s not yet available in the United States. The company says a clinical trial of the device with 30 patients found it provided “comparable” hearing performance to Med-El’s conventional implants, while allowing users to hear while asleep, swimming, and recharging.
“For the first time, all components of a cochlear implant, including the microphone, are implanted beneath the skin. There are no external components to wear, to remove, or to manage,” Hochmair said in a press conference. “This is the realization of a dream that I’ve had for a very long time. For the first time, invisible hearing with a cochlear implant is possible.”
How the Fully Implanted Cochlear Implant Works
The implant weighs 20 grams and is made up of four interconnected components. A subcutaneous microphone the width of a U.S. nickel, or a 5 euro-cent coin, sits roughly 6 millimeters beneath the skin of the scalp and connects to a postage-stamp-size “stimulator” unit that houses both sound processing hardware and a rechargeable lithium-ion battery. This is connected to a coil that’s used to transfer data in and out of the device and recharge the battery. Another lead passes signals to the electrode array in the cochlea, which is the same as the ones used in the company’s conventional devices.
The unit is recharged using a car-key-size unit called a GoPod, which attaches magnetically to the charging coil through the scalp. The battery, which cannot be replaced, is designed to last for up to 40 hours on a single charge of about 1 to 1.5 hours. The company says performance data suggests it will be able to maintain a minimum of 24 hours of use per charge for at least 15 years.
Bringing the microphone inside the scalp presented by far the greatest engineering challenge, said Gerhard Mark, senior R&D engineer at Med-El and project leader for the TICI Unico. “Sound behaves differently when it travels through the tissue, so reaching the performance required years of research, testing, and continuous refinement,” he said, though he declined to provide details on how the company solved the problem.
How Does the Invisible Cochlear Implant Perform?
So far, clinical results suggest the device can provide comparable performance to a conventional cochlear implant, said Philippe Lefebvre, head of the ENT department at University Hospital of Liège, in Belgium, who led a six-patient feasibility study on the implant published in Communications Medicine last year. Hochmair added that other studies have found the same, though that data is still awaiting peer review.
Lefebvre said he had expected the invisibility of the device to be the biggest selling point for users, but in reality the ability to hear around the clock was the main benefit they cited. This was echoed by Diana Grosser, a volunteer who received a TICI Unico in 2024 as part of the clinical trial. “The most meaningful change is freedom,” she said. “I can sometimes forget that I’m deaf, live more freely with my children, swim or ride my motorcycle without worrying about my processor pressing, slipping, or getting lost. I can even choose to hear at night, which gives me additional safety.”
Fan-Gang Zeng, director of the center for Hearing Research at the University of California, Irvine, said, “I applaud Med-El’s launch of this long-overdue device, which not only represents the first meaningful innovation in cochlear implants in the past 30 years since electroacoustic stimulation, but also accelerates the competition that the market desperately needs.”
Zeng, who is not affiliated with Med-El, argues that industry conservatism has been a greater barrier than technical challenges and hopes that a first-mover will push other companies to release similar products soon.