BONE DENSITY MEASURING METHOD

摘要

PURPOSE:To automatically extract a measurement area so as to make it suitable for the measurement of bone density by performing the setting of a measurement object area and the calculation of a correction value for which reproducibility is high based on the anatomical shape of a femur center end part. CONSTITUTION:Since it is considered that the anatomical shape of a femur part in image pickup is approximately the same in the case of the same patient as long as a substantial change such as the fracture of a bone or the like and a large difference in a photographing posture is not present around the femur, the measurement object area 20 is set based on the anatomical shape. That is, without preparing a difference picture 54 in addition to measuring the bone density of the femur center end part, the area measured by a tentative difference picture 52 and a binary picture 53 is extracted and a bone salinity amount is obtained by the cumulative density value of the tentative difference picture 52 and the correction value F. Since BMCN=BMCN '-F is attained when the cumulative density value in the tentative difference picture 52 of an N part 22 is defined as BMCN' for instance and the bone density BMDN becomes BMDN=BMD'-F when a tentative average density value is defined as BMDN' similarly for the bone density, only a threshold density value (t) is used so as to distinguish the bone and soft part tissues.