When conventional hearing aids cannot be used for anatomical or medical reasons, bone-anchored hearing aids are a treatment option under certain conditions. Bone Anchored Hearing Aids - or BAHA for short - are a special form of bone conduction hearing aid that are firmly anchored in the skull bone as hearing aid implant. Using the natural ability of human bones to conduct sound, the powerful implants amplify sounds, allowing active participation in professional and social life.
BAHA hearing aids areas of application
Conventional hearing aids require the middle ear to be involved in the hearing process, so hearing loss involving the middle ear cannot be compensated for with them. As the only implanted form of bone conduction hearing aids, BAHA hearing aids are aimed at treating very severe conductive hearing loss (outer and middle ear are affected) and slight combined hearing loss (middle and inner ear are affected). They are particularly suitable for this purpose because bone-anchored hearing does not require middle ear involvement. Similarly, unilateral sensorineural deafness can be bridged by bone conduction. Because there is no scalp-induced attenuation, as is the case with other designs in the hearing aid family, treatment with the BAHA achieves improved sound results while increasing loudness.
BAHA hearing aids or CROS hearing aids for unilateral deafness?
For unilateral deafness, an indication with CROS hearing aids is possible, in which both the deafened ear and the hearing ear are fitted with hearing aids. For this purpose, the hearing aid on the deafened side picks up acoustic signals and transmits them to the healthy ear, where subsequently a hearing impression can be created in a natural way. Problematic is the missing possibility for directional hearing, because for a complete hearing impression a beidohrige hearing perception is presupposed. Likewise, the need to wear hearing aids on the healthy side is a possible point of criticism.
With bone conduction implants, this can be circumvented: Here, the implantis placed exclusively on the impaired side and allows near-normal hearing on the hearing-impaired ear. However, spatial hearingand directional hearing are also realistic together with the healthy ear. The indication of unilateral deafness assumes that the other ear has adequate hearing. Mild to moderate hearing impairment is not yet an exclusion criterion. In general, unilateral or bilateral hearing impairment determines whether the BAHA is implanted unilaterally or bilaterally.
BAHA implant design and function
The BAHA implant is referred to as a partially implanted hearing aid. The actual implant consists of a titanium screw measuring approximately 4 mm, which is inserted into the skull bone on an outpatient basis under general anesthesia. The procedure takes about 30 minutes. The implant is partially implanted because the upper part of the screw remains visible and protrudes slightly from the skull. Externally, the hearing aid with microphone, sound processor, battery, as well as electromagnetic transducer, which is responsible for recording acoustic information, is attached to this.
The sound picked up by the external part is amplified, translated into vibrations by electromagnetic conversion and delivered to the implant. Natural bone conduction now ensures that this vibration is transmitted to the cochlea in the inner ear. From here, the hair cells convert the signals into electrical impulses that stimulate the auditory nerve. The result: a hearing impression is created.
BAHA implantation: requirements and aftercare
To determine the suitability of a fitting with a BAHA device, the test phase of such a hearing aid, which is attached to a soft band, is possible over a period of several weeks at ENT clinics. In this way, you can try out the hearing system first without risk and without surgical intervention, and check whether this form of hearing amplification is suitable for you. The general prerequisites for insertion are sufficient functioning of the inner ear, the will and the ability to wear and care for the implant, and motivation for hearing training. Intolerances and the health condition must be clarified preoperatively. In children, bone thickness and quality must also be considered.
Following implant placement, a healing time of two to 3 months is to be expected. A hearing care professional should be consulted for adjustment as well as fitting of the new implant and its configuration in the postoperative period to ensure that the implant provides optimal support. In addition to the fine adjustments, the hearing success is largely dependent on the individual motivation for hearing training as well as participation in rehabilitation measures. In addition, regular checks of the BAHA are essential to safeguard its function or prevent complications.
BAHA hearing aid risks
Every surgical procedure carries certain risks, but the insertion of BAHA implants is usually free of complications. Inflammation of the skin or bone is possible, but occurs very rarely. Other potential risks include loosening of the implant or hearing success that does not meet preoperative expectations.
Baha hearing aid cost(coverage)
The cost of the implant and surgery is fully covered by the insurance carrier. However, it is essential to obtain prior approval from the respective health insurance company. In terms of price, BAHA implants are generally within a range of €10,000 - €30,000.