Objective In view of the difficulty in diagnosis of the closed injury of abdomen and the abdominal bleeding,near-infrared spectroscopy is a non invasive,non-polluting new method for abdominal bleeding detection. Methods Monte Carlo method was adopted to simulate the near-infrared light field distribution model. First of all,we established the abdominal multi-layered biology model. Then,in order to explore the photon absorption between the hydrops abdominis and the blood,a simulation of the light intensity s...