Bone-anchored hearing devices (BAHAs) are surgically implanted systems that allow people to hear via bone conduction. These implants are primarily used for people with pervasive conductive or mixed hearing loss but are also approved for use as treatment for unilateral (single-sided) sensorineural hearing loss. In such cases where conventional hearing aids don’t provide benefit but one inner ear is still viable, stimulating the auditory mechanism via bone conduction may provide significant benefit.
How Does the BAHA Work?
In individuals whose middle or inner ear isn’t functioning properly, sound has difficulty reaching the nerve pathways that connect the inner ear to the brain. A bone-anchored device works by utilizing natural bone transmission as a pathway for sounds to travel to the inner ear, essentially bypassing the normal pathway of hearing through the external ear canal and middle ear.
A titanium implant is attached to the skull during a short surgical procedure, which naturally integrates with the bone over time. The external abutment attaches to the implant and acts as a transmitter for a sound processor, which is directly attached to the external portion of the implant. The sound processor transmits sound vibrations through the external abutment to the titanium implant in the skull. These vibrations transmit through the skull and the inner ear, stimulating the nerves that allow hearing to occur.
Benefits of a Bone-Anchored Hearing Devices
For some, a bone-anchored hearing system can be a life-changing experience. Where other methods may have failed due to physical or logistical reasons, a bone-anchored hearing devices normalizes hearing for some people.
- For those with chronic ear infections: Ear infections tend to affect the outer or middle ear, which creates a conduction problem for sound. For cases in which chronic infections are present, and therefore make it difficult or painful to wear a hearing aid, bone-anchored devices are a useful solution for hearing rehabilitation.
- For those with congenital hearing loss: A congenital hearing loss might involve malformation or absence of the middle or external ear at birth. Such malformations of the ear can make hearing aid use difficult or impossible. For cases in which the inner ear is healthy and able to detect sound, bone-anchored devices can help.
- For those with single-sided hearing loss: Hearing that is symmetrical and normal for both ears is extremely important. Severely diminished hearing acuity in one ear is far less efficient than normal binaural hearing. Asymmetrical hearing loss can make it both difficult to understand speech in background noise and harder to localize sound. Bone-anchored devices are an effective treatment for those with single-sided deafness due to a viral infection, trauma, tumors on the auditory nerve, or surgical intervention. Symmetrical hearing in both ears greatly improves speech understanding during conversation, especially in noisy environments.
Am I a Candidate for a Bone-Anchored Hearing Aid?
Bone-conduction hearing devices are used to help those who experience chronic ear infections, congenital auditory conditions, and unilateral deafness in cases where conventional hearing aids are ineffective or unable to be worn. Those who experience conductive or mixed hearing loss due to medical difficulties, or severe single-sided sensorineural hearing loss, may be eligible for bone-anchored hearing systems.