Modelling of the interactions between implanted auditory prosthesis and 900 MHz radiofrequency: Application to cochlear implants

The rapid diffusion of environmental electromagnetic radiations, in particular in the radiofrequency range, is determining increasing interest on their possible consequent health effects. A particular attention is deserved to those subjects who are considered to be more sensitive such as people who use cochlear implants. Cochlear implants (CI) are electronic devices that restore partial hearing to deaf or severely hard of hearing people. Aim of this study was to analyze the possible functional interactions of RF microwaves with CI. Results of this study show that the electrode array inside a cochlea exposed to an external radiofrequency EMF source at 900 MHz produced peaks on the amplitude of the electric and magnetic fields near the implant and a consequent local increase of the absorbed power and tissue temperature. Moreover, peaks of current density in correspondence of the electrodes were found, with average values of about 4 ¿A.