In view of the problems and the like of the prior art, the purpose of the present invention is to provide a method for imaging
body tissue rapidly and robustly using
waveform inversion from
ultrasound examination data. The method for imaging
body tissue rapidly and robustly using
waveform inversion from
ultrasound examination data according to the present invention comprises: (a) a step for acquiring
ultrasound examination data; (b) a step for generating one
wave field by means of a plurality of computers (CPUs); (c) a step for integrating squared errors (which constitute fc in expression (5)) from all CPUs, each squared error being the error between a waveform recorded at a reception point from the
wave field and an observed waveform obtained in step (a); (d) a step for re-dividing a correction gradient and a pseudo Hessian matrix into regions with an equal number of CPUs in the x-direction; (e) a step for re-dividing from the uniform regions in the x-direction into regions with an equal number of CPUs in the y-direction; (f) a step for calculating a step length required for model updating in full-
waveform inversion using a quasi-Newton method while maintaining the division of regions in the x-direction; and (g) a step for repeating the steps (b) to (f) to obtain imaging of a
viscosity Q value in addition to a
sound wave propagation velocity. Expression 5: Here, fc (scalar quantity) is a cost function representing the sum of squared residuals between the observed data (d_obs) and the
synthetic data (d_syn) calculated from the initial model at all times of all reception points, and Ns, Nr, Nt are respectively the number of transmission points, the number of reception points, and the number of time samples.