A medical imaging system having a patient support apparatus is provided. The medical imaging system includes a framework portion and a kit of rigid modular patient support panels, constructed of material having a radiation attenuation coefficient less than that of metals. The panels in sub-combination are removably mounted to and supported by the framework portion. The panels are selectively assembled to define varying surface profiles, including selective gaps there between, that are capable of conforming a patient in contact with the surface profile in a range of supported body positions from supine to seated.