Bone-conduction HR Flashcards
Bone conduction Based hearing aids
Used when patient’s can’t wear traditional amplification:
Auditory disorders (Cronic otitis media, middle ear malformations, congenital atresia, Otosclerosis)
ACHAs might exacerbate chronic external otitis or outer ear infection
Impractical in PA with Congenital aural atresia combined with Microtia or Anotia
main advantages of bone conduction implants
- Conductive component is bypassed
- Good sound quality
- Evidence-based research
- Minimally invasive surgery
- No risk of further damage to hearing
- No occlusion of the ear canal
- System can be tested before surgery
BCHA
Bone-conduction hearing aid (BCHA):
A vibrator pressed firmly against the skin of the skull via a still spring coupled to a band.
May cause discomfort, pressure sores and headaches.
Baha meaning
Bone-anchored hearing aid (BAHA):
FDA approved since 2002.
Bone-conduction implant that combines a sound processor with a small titanium fixture implanted behind the ear.
Baha
Mic on sound processor picks up sounds
SP converts into vibrations and transfers them through abutment or magnet to the implant
Implant transfers vibrations through skull to inner ear
Good for conductive losses or Single-sided deafness
The Baha Attract System®
The Baha Attract System® transmits sound vibrations to the inner ear through a magnetic connection between the sound processor and the implant under the skin. The benefit being that there is no skin penetrating abutment, providing a good aesthetic outcome with no need for daily care
The Baha Connect System*
The Baha Connect System* transmits vibrations through an abutment which connects the sound processor to the implant.
Using the DermaLock” technology the skin is left intact around the abutment. Here the major benefit is the efficient transmission of vibrations, providing maximum amplification.
The Baha Softband
The Baha Softband uses a flexible headband to hold the sound processor, which transmit vibrations to the bone through the skin. This system facilitates early aiding of children before surgery is warranted, and can also help people for whom surgery is contraindicated.
SELECTION CRITERIA
Conductive hearing loss
Conductive hearing loss
Most candidates with conductive hearing loss will benefit from a Baha
System. As the Baha System sends sound directly to the cochlea via bone conduction, the conductive element of the hearing loss is effectively
-bypassed. This means that less amplification is required compared to other solutions.
Selection criteria:
• Degree of conductive hearing loss - studies suggest that candidates with an air-bone gap of more than 30 B (PTA4) will experience significant advantages from the Baha System, compared to using an air conduction (AC) hearing aid.!
SELECTION CRITERIA
Single-sided Sensorineural Deafness (SSD)
Single-sided Sensorineural Deafness (SSD)
Candidates with SSD and normal hearing in their good ear may benefit from a Baha System.’ The Baha sound processor picks up sound on the deaf side and sends it via bone conduction to the contralateral cochlea, overcoming the head shadow effect. This gives improved speech understanding and 360° sound awareness 5-7
Selection criteria:
The level of hearing in the good ear- should be assessed. Candidates with normal hearing in their good ear will benefit from a Baha System. In cases where there is a more pronounced hearing loss in the good ear, a bone conduction implant may not be the best solution.
• Candidate motivation - as SSD patients may have specific expectations due to their type of hearing loss, it is important to ensure such expectations are realistic and that they perceive the prospect of hearing from their deaf side as a need.
Selection criteria
Mixed hearing loss
Mixed hearing loss
Many individuals with mixed hearing loss are suitable candidates. Bypassing the conductive element of the hearing loss means that less amplification is required because the Baha System only needs to compensate for the sensorineural loss.
Selection criteria:
• Degree of conductive hearing loss - the air-bone gap is a good indicator of suitability for a Baha System. The greater the air-bone gap, the more the
- candidate will benefit from implantable bone conduction system. Studies suggest that candidates with an air-bone gap of more than 30-35 dB (PTA4) derive greater benefit from a Baha System than a hearing aid.
Extent of the sensorineural hearing loss - those with a mild-to-moderate sensorineural component in their hearing loss are suitable Baha candidates. The Baha sound processor can compensate for some of the sensorineural loss but, as the conductive part of the loss is bypassed, only modest amplification is required - much less than is necessary with conventional hearing aids. The most powerful Baha sound processor can compensate for a sensorineural element of up to 65 dB HL (measured at 0.5, 1, 2 and 3 kHz).
