A method for performing tomography on a structure supporting modes of guided propagation of elastic waves, the method includes the steps of: acquiring a plurality of signals propagating through the structure by means of a plurality of pairs of non-collocated elastic-wave sensors; for each pair of sensors, i. selecting one mode of guided propagation, ii. converting the measured signal into wave field for the selected mode, iii. determining an anisotropic calibration coefficient on the basis of a wave-field propagation model evaluated depending on the anisotropic wavenumber and on the distance between the sensors of the pair, and on the basis of the wave field or of a reference wave field corresponding to a healthy state of the structure, calibrating the wave fields using the determined calibration coefficients, performing tomography on the structure on the basis of the calibrated wave fields.