Stapedectomy surgery for a conductive or mixed hearing loss due to otosclerosis usually has wonderful results. The hearing threshold is improved and the quality of sound is very natural. However it does carry risk of a dead ear, which occurs in 0.5-1.0% of surgeries despite the surgery being carried out competently. In

this situation it would leave only one hearing ear on the opposite side. In such a situation it would be strongly advisable not to undergo surgery on the opposite side because of the small risk of a second dead ear. Fortunately there are several options for rehabilitating hearing in this situation with hearing aids of various kinds. A bone anchored hearing aid (BAHA) is one such device which can help. It is placed under the skin in the mastoid bone behind the ear and works by bypassing the middle ear and stimulating the cochlea directly through the bone of the skull. BAHAs have predictable hearing outcomes in conductive hearing losses. This hearing result can be experienced by a trial simulation of the BAHA before undergoing surgery to implant the device. The surgery to implant a BAHA is simple and carries no risk to the underlying hearing. An external speech processor held on by a magnet or small clip generates sound vibration to be transmitted to the implant under the skin.

There are several other kinds of middle ear devices which can also be used in this situation. A device which has recently become available in Australia is the Bonebridge. This is an active middle ear implant which has the source producing the sound vibrations implanted within the mastoid bone behind the ear, rather than externally in the speech processor as with the BAHA. Many other implantable devices which can help are also being investigated. Some are active devices that attach to the middle ear bones such as the Vibrant sound bridge. However these devices require more complex surgery than the Bone Bridge or BAHA for placement. They also required manipulation of the middle ear bones, and hence carry a risk to the underlying hearing. These devices would not be suitable for surgery on the side of an only hearing ear.