Researchers have evaluated the effectiveness of bone-anchored hearing aid implants compared to reconstructive surgery in children and adolescents, and the hearing aids proved superior.
Hearing Defects in Children
Aural atresia, a birth defect which typically results in a deformed outer ear and middle ear, affects one in 10,000-20,000 children a year and can lead to complications in speech development.
Researchers wanted to examine the quality of life for children that were treated and see whether congenital aural atresia is better addressed with ear canal surgery or by a bone-anchored hearing aid.
Reconstructive Surgery vs. Bone-anchored Hearing Aids
Reconstructive surgery for the disease was first attempted it 1883, resulting in facial nerve paralysis and continuous bouts of hearing loss. Bone-anchored hearing aids, invented almost 100 years later in 1977, involve anchoring a titanium screw into the mastoid process of the skull with an external piece protruding from the skin. A removable hearing aid can be attached and detached from this external piece.
The bone-anchoring process relies on sound waves to be channeled from the hearing aid to the vestibulocochlear nerve embedded in the skull. The titanium screw acts as a medium, relaying the external signal past the surface of the skull. The entire process relies on osseointegration, applying an implant to bone in the hopes that it will be incorporated into the regenerating bone tissue.
Procedures and Complications with Bone-anchored Hearing Aids
The test group consisted of children diagnosed with aural atresia or stenosis. Nineteen received a bone-anchored hearing aid and 49 received external auditory canal reconstruction.
Short-term hearing examinations, performed less than six months after surgery, and long-term hearing examinations, completed more than a year after surgery, were necessary to test whether the procedures had any adverse effects.
The researchers assessed the quality of the patients’ post-operational hearing and submitted a questionnaire to a subset of the group evaluating their quality of life. In both the short term and long term examinations, the group that was given the bone-anchored hearing aids performed significantly better on hearing tests than patients who received external auditory canal reconstruction.
The researchers concluded that there wasn’t a great difference in the quality of life of these patients according to the questionnaire. Although there weren’t severe complications during or after surgery for either group, the bone-anchored hearing aid appears to be a more suitable choice simply by virtue of its increased audiometric performance.