Bone Anchored Implant

A bone-anchored auditory implant (BAI) is a surgically implanted device to enhance hearing in patients with certain types of hearing loss — including conductive hearing loss, mixed hearing loss and single-sided deafness.

A BAI can be helpful for someone who cannot tolerate traditional hearing devices or who has had middle ear surgeries and are not candidates for additional surgeries.

What is a bone-anchored auditory implant?
What does BAI surgery involve?
Is a bone-anchored auditory implant for me?
Single-sided deafness (SSD) and bone-anchored auditory implants
Manufacturers of bone-anchored auditory implants

What is a bone-anchored auditory implant?

A BAI is a surgically implanted hearing aid composed of two major components.

The first is typically a titanium implant, made up of a screw and an abutment that is surgically placed into the skull just above and slightly behind the ear. In some cases, the implant can be made with an external magnet rather than an abutment, which prevents anything from showing through the skin.

The second component, a speech processor, is snapped onto the abutment — or held in place with a magnet — from outside the skull. Sound waves vibrate the speech processor, which sends signals directly to the inner ear.

What does BAI surgery involve?

A titanium abutment can typically be surgically placed in one procedure. Within about four weeks for adults, and six months for children, the titanium abutment integrates into the skull.

In some cases, the surgery must be performed in two stages. This is often necessary in young children and in adults with poor bone quality or craniofacial abnormalities. If necessary, stage 1 involves a surgery to place the titanium implant. Stage 2 requires a small procedure in order to open the skin to expose the implant so that the abutment can be placed.

Magnetic BAI

Another alternative for some people is magnetic BAI, which is done in a single surgery. During the procedure, the surgeon places a special magnet beneath the skin behind the affected ear. Once the swelling goes down — usually within four to six weeks — an external magnet and speech processor are placed, and the device is programmed.

Your surgeon will discuss this with you if you are a candidate for the external magnet.

Is a bone-anchored auditory implant for me?

You or your child may be a candidate for a BAI if you have mild to severe conductive or mixed hearing loss in one or both ears resulting from:

  • A congenital malformation of the external ear or ear canal
  • Chronic drainage in the ear canal impairing traditional hearing aid use
  • Hearing restoration surgery that has failed
  • Otosclerosis
  • Cholesteatoma
  • Chronic middle ear infections

The FDA has approved bone-anchored auditory implants for people five years and older. The speech processor only needs to be removed before swimming or bathing. In children younger than five years old, the speech processor can be worn externally on a headband without requiring surgery.

Single-sided deafness and bone-anchored implants

Single-sided deafness (SSD) is severe-to-profound sensorineural hearing loss in one ear and normal or nearly normal hearing in the other ear.

People with single-sided deafness struggle to distinguish voices in a crowd, and they cannot always tell which direction sound is coming from. While the brain adapts to these limitations, it has to work much harder to interpret sounds.

Single-sided deafness can result from:

  • Skull-base tumors, including Vestibular Schwannoma
  • Head injury or trauma
  • Advanced otosclerosis
  • Sudden hearing loss
  • Hearing restoration surgery that has failed
  • Congenital or acquired hearing loss

In these cases, the BAI is always implanted on the deaf side. The system picks up all the signals coming from the deaf side and transmits them to the inner ear of the hearing ear.

A bone-anchored auditory implant helps people with single-sided deafness hear more of what is going on in the world around them and pick up conversations they may have missed before. It does not, however, help them tell what direction a sound is coming from or allow them to hear in stereo.

Manufacturers of bone-anchored auditory implants

The neurotologists at Virginia Mason’s Listen for Life Center use bone-anchored auditory implants manufactured by Oticon Medical and Cochlear.