Abstract
X-ray computed tomography (CT) is widely used in the field of medicine for diagnostic purposes, but the radiation dose to which the patient is exposed must be kept to a minimum. Grids are used to eliminate the harmful scattered radiation that occurs with current X-ray CT machines. However, because objects cause scattered radiation, information about the objects can be extracted from it. Using the Monte Carlo method to calculate the amount of scattered radiation, we constructed a maximum likelihood method to estimate its attenuation coefficient. The accuracy of the estimation was evaluated by the mean square error between the estimated value and the true value. Numerical simulation showed that the accuracy of the estimated attenuation coefficient improved without increasing the radiation exposure dose by utilizing the scattered radiation.
