Cochlear implants are indicated when the patient has significant hearing loss in both ears. In addition, the ear to be implanted must still have the cochlear nerve and blood supply intact. Unfortunately, this is often not the case in patients with acoustic neuromas because of the size of the tumor or treatment with radiation and/or surgery. However, some patients after tumor removal have some remaining hearing, and then they lose hearing in the other ear. It is a small complex electronic device that is implanted within the inner ear to increase hearing capabilities. Whereas hearing aids amplify sound, cochlear implants compensate for damaged or non-working parts of the inner ear. A cochlear implant electronically finds useful sounds and then sends them to the brain.