Funcţia otolitică la pacienţii implantaţi cohlear

Introduction. The cochlear implant is the gold standard treatment for profound and severe deafness that cannot be adequately corrected by hearing aids. The surgical procedure of implantation and the persistence of the electrode in the inner ear space may cause temporary dysfunction or permanent lesion of the vestibular receptors, especially of otolithic organs (sacculus and utricle). VEMP (Vestibular Evoked Miogenic Potentials) represents an electrophysiological method of the ves­tibular assessment protocol, testing the saccular func­tion (cervical VEMP) and the utricular function (ocular VEMP). Materials and method. The study included a group of 27 patients, representing 32 implanted ears (12 patients with binaural implant and 8 patients with monoaural implant), which were tested with cervical and ocular VEMP after cochlear implantation. The results were compared with those of a control group represented by 22 non-implanted ears afected by profound hearing loss. Results. VEMP ocular testing indicated a normal utricular function in 59.32% of the implanted ears, while 40.63% showed utricular areflexia. Cervical VEMP testing showed that 65.63% of the implanted ears had normal saccular function, and 34.38% had saccular partial or complete deficit. In the control group, 65% of the ears showed physiological utricular response and 68.18% had normal saccular response. Conclusions. The differences in the status of the otolithic receptors between the implanted ears and the control group suggests that cochlear implantation is a risk factor for peripheral vestibular lesions.