Abstract: Systems and methods for accurately calculating radiation doses in biological tissues exposed to a radiation source are provided. In the systems and methods first, a radiation dose is computed to geometry of water equivalent medium of the biological tissues, expressed in computed tomography (CT) volumetric images. A Medium-Dependent-Correction factor that is a function of an effective bone depth matrix and the incident x-ray beam is obtained and tabulated. Using patient material and density data derived from CT images, the effective bone thickness can be calculated from a specific x-ray source. Finally, a Medium-Dependent-Correction factor that is a function of an effective bone depth matrix is used to accurately determine the radiation dose distributions to biological tissues.