Histological studies of the radiation effects of the rabbit normal urinary bladder wall

Histophathological alterations were studied in the rabbit bladder wall after irradiation with different fractionations and total doses in 180 animals altogether. The animals killed one week after the end of irradiation predominantly showed alterations in urothelium (desquamation, splintering, increased nuclear polymorphism, and vacuolisation) as well as dedmatous and hyperemic reactions in the submucosa and the muscularis. These alterations increased with higher single and total dose. In animals killed 3 to 6 months after the end of irradiation dystrophic-sclerosing alterations as well as vessel obliterations predominated in submucosa and muscularis. These alterations were relevant only from a total dose of 30 Gy. In radiotherapy of bladder carcinoma a fractionation with 1.5 Gy daily is the best with regard to the slightest histopathological alterations in normal bladder wall. (author)