X線減弱係数の仕分けと医用画像

抄録

In recent years, there is a growing demand for the accountability of those who manage to reduce patient dose for x‐ray imaging to the necessary minimum. Following the concept of ALARA（as low as reasonably achievable）, radiologists and physicists will need to work collaboratively to determine the appropriate image quality for diagnostic x‐ray imaging. The analysis and understanding of results of x‐ray imaging require an understanding of photon attenuation in matter. With this goal in mind, a discussion of photon attenuation in matter is given and related to those behavior to x‐ray imaging parameter, especially in the case of tube voltage dependency for polychromatic beam. Simulation studies were carried out to find the optimal tube voltage for the signal‐to‐noise ratio in projection imaging and computed tomography with polychromatic x‐ray source. In addition, material decomposition using dual‐energy CT reconstruction is introduced for relating linear attenuation coefficient to tissue composition and structure.