Comparison of geometric and "real" surface areas of cochlear electrodes.
The destructive potential of the electrically active electrode is believed to be related to charge density at the electrode-tissue surface. Charge density has been calculated with the use of both geometric and electrochemical "real" values for surface area. To further assess the accuracy of surface area measurements determined by means of the previously mentioned methods, an eight-electrode modiolar array cochlear implant was examined. Electrode surface areas were measured first electrochemically, then by means of a light microscope, and finally with the use of the scanning electron microscope. Comparison of these measurements demonstrated a high correlation between the scanning and light microscopic values. However, there was no correlation between the surface areas determined by light and scanning electron microscopy and the electrochemical measurements.
D003054:Cochlear Implants; D004567:Electrodes, Implanted / Q000009:adverse effects*; D008855:Microscopy, Electron, Scanning; D013499:Surface Properties