what these images show will depend on three things: rayleigh scattering, compton scattering and photoabsorption. the images show bone because it is dense enough that x-rays are not able to pass through it. instead, the x-rays are either absorbed or scattered. the images do not show skin and muscle, however, because these tissues are transparent enough for the x-rays to pass through them without being absorbed too much. to detect tumors, other imaging devices are used; such as magnetic resonance imaging. a computed tomography scanner combines an x-ray machine and computer to construct a three dimensional (3d) picture. this has some ability to see other things besides bone.