The operation is carried out under general anaesthetic and lasts for between 2 to 4 hours. To maintain sterility, it is necessary to shave the hair directly behind the ear to receive the implant. The surgery is carried out in several stages: the surgeon makes an incision behind the ear the innovative fixation system of the Digisonic®SP allows for reliable fixation of the implant on the bone without requiring bone drilling a small opening is made in the cochlea in order to place the electrode array. It is kept in place using a strong suture. the surgeon closes the incision. The surgery may last longer, especially in cases of ossification of the cochlea, due perhaps to a previous meningitis. The surgeon must make small holes in the bone formed in the cochlea to place the different electrode arrays to be used (see Products). In rare cases, the patient requires an implant directly into the brainstem. This is a very delicate surgical procedure lasting several hours and entails certain risks. During the operation, when the surgeon has completed the implant, electrophysiological tests are carried out. These tests allow the clinician to check: that the implant is functioning correctly the auditory nerve’s capacity to receive stimulation and transmit it to the brain where it is to be interpreted. The surgery requires the patient to remain in hospital for a few days and complications are very rare. Total recovery after the operation includes recovery from the anaesthetic, scar healing at the place where the incision was made, and may take a few weeks.