[Comparative investigations (computed tomography, X-ray diagnostics, scintigraphy) for the detection of radiation-induced alterations of the lung (author's transl)]

Abstract

Radiation-induced alterations of the parenchyma of the lung were investigated in 24 rabbits before, during and after irradiation of the left lung. Of the experimental animals 12 received a surface dose of 50 Gy, the other half 40 Gy, equivalent to a focal dose of 47.5 resp. 38 Gy in the middle of the lung, with a fractionation of 10 Gy per week. By means of lung-scintigraphy (99mTc-MAA) radiation-induced obstructions to perfusion could be demonstrated in 93% of the experimental animals, only in 37% the detection of radiopneumonia was possible by computed tomography or by a roentgenogram of the thorax. In 70% of the experimental animals scintigraphic alterations could be detected already during radiotherapy, the alterations visible by computed tomography or roentgenology appeared much later. Here computed tomography allowed an earlier identification of differences in absorption than X-ray diagnostics.