A method, including sequentially activating a plurality of respective electrode pairs of an implanted cochlear implant, at least one of the electrodes of the respective electrode pairs being a respective electrode of an electrode array implanted in a cochlea, thereby generating respective localized electric fields, concurrently respectively measuring, for the plurality of activated respective electrode pairs, an electrical characteristic between the respective electrodes of the respective electrode pairs resulting from the respective localized electric fields, thereby obtaining a measurement set, determining, from the measurement set, a distance between the electrode array and a wall of the cochlea.
