This study presents a measurement method of detailed distribution of mechanical properties of bone tissue using a scanning acoustic microscope (SAM). In this method, ultrasound reflection intensities in micro area of the bone tissue are calibrated with luminance values of pixels in a C-mode image of it measured by SAM. Minute distribution of density and elastic modulus could be analyzed by combining the XZ-mode which is used to measure the surface wave velosity. Mechanical properties of femur bones of elderly human and young beagle dog were evaluated by this method. It was found that the elastic modulus in the endosteum side of femur bone of young canine was lower than that in the periosteum side of it. Meanwhile, in the femur bone of elderly human, the elastic modulus in both sides were approximately equal.
