Novel intracochlear electrode positioner: Effects on electrode position

Spiral ganglion cells, located in the cochlear modiolus, are widely thought to be the neural elements stimulated by cochlear implants (CIs). Positioni ng CI electrodes adjacent to the modiolus may allow delivery of more focuse d, discrete fields of electrical stimulation, reducing both current require ments and the channel interaction associated with simultaneous stimulation. In order to provide greater consistency in positioning CI electrodes again st the modiolus, Advanced Bionics Corporation has designed a silicone intra cochlear positioner that is inserted alongside the electrode. Placed agains t the outer wall of the scala tympani, it directs the electrode array towar d the modiolus. Five fresh-frozen temporal bones were studied to validate e nhanced electrode placement. Electrode position was documented with image-e nhanced digital fluoroscopy, and the distance to the modiolus was measured with computer-assisted morphometrics. The electrode positioner was highly e ffective in positioning the electrodes closer to the modiolus (p<.001).