A method of identifying upon insertion into soft tissue a microelectrode of a set of three or more microelectrodes each comprising an electrically conductive body comprises providing the microelectrode with a unique metallic pattern of three or more sections separated from each other and disposed in an axial direction on the body and/or on one or more insulating layers on the body; inserting the microelectrode into the tissue simultaneously or consecutively with the other microelectrodes of the set; detecting the pattern by computer tomography (CT) or X-ray. Also disclosed are microelectrodes provided with unique patterns and sets of such microelectrodes and their use.