[Fractionated irradiations of the normal rabbit lung with fast neutrons or photons]

115 rabbits were irradiated with our usual fractionation scheme, and the dose effect curves for fast neutrons and photons (60Co) were determined with respect to pneumonitis and pulmonary fibrosis, respectively. On comparison of the radiogenic alterations three months after therapy, the relative biological effectiveness calculated by means of these dose effect curves was 2,9 for the fast neutrons. Furthermore, the authors tested the conformity of some clinical examination methods such as X-ray, scintigraphy and computed tomography with histological findings of pneumonitis and pulmonary fibrosis, respectively. In this regard, computed tomography was superior to the other examination methods.