Position coordinate information of each point three-dimensionally forming a tissue corresponding to a diagnosis target at each time phase is obtained, a quantitative value for evaluating the movement of the tissue corresponding to the diagnosis target is calculated by using the position information, and the result is output in a predetermined form. Accordingly, since the quantitative value for evaluating the movement is calculated by using the three-dimensional position coordinate information without converting wall movement information obtained by a three-dimensional tracking process into two-dimensional information, it is possible to provide medical information with a higher degree of precision.