The simulation of a multi energy bone mineral densitometry method

The developing of photon counting detectors makes it is feasible to obtain multi energy information from one X-ray source. Based on the photon counting system, this paper proposes a simulation of multi energy BMD method, which can lead to the promotion of current BMD accuracy as well as providing multi information of human tissue. In our simulation, we generalize the conic surface equation fitting method used in DEXA. In order to adapt to the multi energy condition, the conic surface equation is extended. A model of human forearm cross profile composed by five types of tissue (adipose, muscle, bone, blood and contrast agent) is used in attenuation. To imitate the photon counting system, the attenuation data from 20 keV to 120 keV is separated into five energy segments. As a comparison, dual energy information is also collected in this system. Our goal is to compare the accuracy between multi energy system and dual energy one, as well as to verify the density measurement of other tissue.