Implanted Hearing Aids

A bone anchored hearing aid (BAHA) is a device that transmits sound energy through vibration of the skull, bypassing the ear canal, eardrum and the middle ear hearing bones, and provides better results than a traditional hearing aid worn in the ear, in certain patients.

BAHA is indicated in certain groups of patients:

  • Conductive (mechanical) hearing loss
  • Unable to utilize a conventional hearing aid
  • Those with congenital aural atresia
  • Those with mastoid cavities or chronic infection made worse by hearing aids
  • Single sided nerve hearing loss
  • Those who have single-sided deafness from surgery (i.e., acoustic neuroma excision, labyrinthectomy), injury, viral induced deafness, among others

Adequate inner ear function (cochlear reserve) on at least one side is important for the success of this device. A trial using a bone conduction device prior to surgery is important in establishing performance and satisfaction. This trial is done with a head band that simulates the implant, known as a “soft band trial”. A soft band trial can be arranged through most audiologists and hearing aid sales centres.

How does a BAHA work?

A titanium implant (screw) is placed behind the ear through a small operation. The implant is placed about 4 mm into the outer table of the skull; it is allowed to integrate into the bony tissue over a 3-4 month period. The skin/scalp surrounding the screw is thinned out to optimize this process.

Once the implant is firmly attached to the skull, an external sound processor/bone conductor is applied and turned on.