Table III.

Implantable Devices: partially or totally implantable hearing devices, typically recommended for individuals with extreme or atypical hearing loss who cannot wear or benefit from conventional hearing aids.

Type	Description	Pros	Cons	Appropriate for
Cochlear implant	An electronic hearing device that consists of an electrode array inserted into the cochlea to directly stimulate neural pathways. The external component consists of a microphone, sound processor and transmitter, which communicates with the internal device by a magnet positioned behind the ear.	-Potential to restore functional hearing and speech perception for individuals with severe to profound deafness who do not benefit from conventional hearing aids -Some models can be used during water activities	-Surgery -Potential complications from surgery -Ongoing risk of serious infection -Can be costly, although many insurance companies cover the cost -Risk of device failure -Down the line need for repeated surgeries to replace components -Many are not MRI compatible	Children and adults diagnosed with severe to profound deafness who do not benefit from conventional hearing aids.
Hybrid Cochlear Implant	An amplification system combining acoustic amplification via a hearing aid worn behind the ear with electrical amplification delivered via a cochlear implant.	-Potential to restore functional hearing and speech perception for individuals with severe to profound mid to high-frequency deafness who do not benefit from conventional hearing aids	-Surgery -Potential complications from surgery such as damage to residual low- frequency hearing -Ongoing risk of serious infection -Can be costly, although many insurance companies cover the cost -Risk of device failure -Down the line need for repeated surgeries to replace components -Intended for use on one ear only. -Not yet approved for use in children <18 years of age -Not MRI compatible	FDA approved (2014) for adults aged ≥18 years with normal to moderate low- frequency hearing loss and severe to profound mid to high-frequency hearing loss who do not benefit from conventional hearing aid use.
Osseo-integrated cochlear stimulators (bone conduction hearing devices)	A hearing aid system consisting of either: 1) a titanium fixture implanted into the skull behind the ear. A percutaneous abutment connects the sound processor to the titanium fixture, or 2) a sound processor held in placed by an implanted magnet (abutment free) Sound travels through the bone to stimulate the cochlea, bypassing the outer and middle ear spaces.	-More cosmetically appealing and comfortable than the conventional bone conduction hearing aid with metal headband -Generally provides excellent benefit for those with conductive or mixed loss; more variable for those with single-sided deafness	-Surgery -Costly -Potential complication from surgery	Surgical implant is approved for age ≥5 years. Children <5 years may wear the bone oscillating sound processor with a soft headband. Appropriate for those with conductive and mixed hearing losses as well as single-sided deafness
Middle ear implant	An implantable device that stimulates the middle ear structures directly. Some devices are partially implanted while others are completely implanted (invisible).	-Improved sound quality by directly stimulating the ossicles -Improved comfort by allowing the ear canal to remain open -Cosmetically appealing -Can be worn during water activities	-Surgery -Costly -Potential complications from surgery -Risk of device failure -Repeated surgeries to replace battery (average battery life is 4.5–9 years).	Currently, only two devices are FDA approved for people 18 years and older. Appropriate for people with moderate to severe sensorineural hearing loss who cannot wear or do not benefit from conventional hearing aids. Future applications may apply to those with conductive loss as well.
Auditory brainstem implant	A prosthetic hearing device that directly stimulates neurons on the brainstem bypassing the cochlea and auditory nerve.	Potential to restore some functional hearing and speech perception for individuals diagnosed with neural deafness.	-Surgery -Costly -Potential complications from surgery -Risk of device failure -Wide range of adult patient reported benefit and performance	FDA approved for adults and most recently for children enrolled in clinical trials (as of Jan. 2013) diagnosed with profound hearing loss secondary to cranial nerve VIII (auditory nerve) insult.