The mastoid bone is opened, leading to the middle ear. The operation takes from I.5 to 5 hours depending on the specific cochlear implant being used. The hospital stay varies from one night to several days, depending on the device used and the patient's needs. The microphone receives sound. It transmits sound to the speech processor, which selects and codes sounds useful speech.
Electrodes stimulate the hearing nerve.
These signals are recognized as sound by the brain. The microphone and transmitter are worn behind the ear. A thin cord connects the microphone to the transmitter and to the speech processor. Instruction in the care and maintenance of the system and training in listening to sound through the implant are provided at that time. Cochlear implant programs differ in the amount of time required to fit the device and the amount of training provided.