| abstract |
It is proposed to modify a X-ray diagnostic device so that both the diagnosis is preserved, as well as the radiotherapy of tumors is possible. To improve diagnostics, X-ray contrast agents are used, as usual in X-ray diagnostics. For dose enhancement in radiotherapy mode, contrast agents containing one or more atoms of heavy elements are also used. The dose increase is based on the photoelectric effect. The tumor is only irradiated as long as a target concentration of the contrast medium is exceeded in the tumor. Preferred diagnostic x-ray devices are computed tomographs equipped with high-performance x-ray tubes and operated with high voltages in the range up to 140 kV or more. The modifications to the transition from the diagnostic to the therapy mode relate to the additional modules X-ray concentrator 3 and fluorescence detector unit 6. With the X-ray concentrator 3, which is pushed mechanically or computer-controlled electromechanically into the steel path, the X-ray beam is focused monochromatized with optimal energies for the dose increase of the contrast agent and on the target area. With the fluorescence detector 6, the concentration of the contrast agent in the tumor 11 is measured on-line during the irradiation. Alternatively, the concentration must be determined from the diagnostic image by quickly switching to the diagnostic mode. |