Methods and apparatuses for characterization of body tissue are disclosed in which bioimpedance across a tissue region of interest is determined. A first electrical signal is applied between an inner pair of current electrodes (B,C) and one or more voltages are measured between an outer pair of sensing electrodes (A,D) and/or between one of the outer pair of sensing electrodes (A,D) and one of the inner pair of current electrodes (B,C). In some embodiments, the methods and apparatuses provide for characterization of electrode-to-tissue contact.
